USRE48994E1

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Publication number: USRE48994E1
Application number: US16/432,928
Authority: US
Inventors: Joseph Yudovsky; Mei Chang; Faruk Gungor; Paul F. Ma; David Chu; Chien-Teh Kao; Hyman W. H. Lam; Dien-Yeh Wu
Original assignee: Applied Materials Inc
Current assignee: Applied Materials Inc
Priority date: 2011-10-19
Filing date: 2019-06-06
Publication date: 2022-03-29
Also published as: USRE47440E1; KR102204305B1; CN108796472B; US9109754B2; KR102010469B1; CN103890912B; TWI627368B; KR20200118259A; US20130098477A1; TWI614446B; KR20190095549A; TWI680255B; TW201840948A; TWI786341B; CN103890912A; TW202024520A; CN107365977B; CN107365977A; WO2013059591A1; TW201326632A

Abstract

Provided are gas distribution apparatus with a delivery channel having an inlet end, an outlet end and a plurality of apertures spaced along the length. The inlet end is connectable to an inlet gas source and the outlet end is connectable with a vacuum source. Also provided are gas distribution apparatus with spiral delivery channels, intertwined spiral delivery channels, splitting delivery channels, merging delivery channels and shaped delivery channels in which an inlet end and outlet end are configured for rapid exchange of gas within the delivery channels.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 61/548,942, filed Oct. 19, 2011.

More than one reissue application has been filed for the reissue of U.S. Pat. No. 9,109,754 B2. This application is a continuation reissue of application Ser. No. 15/678,883, which is an application for reissue of U.S. Pat. No. 9,109,754 B2, and is also a reissue of U.S. Pat. No. 9,109,754 B2, the contents of which are incorporated herein by reference.

BACKGROUND

Embodiments of the invention generally relate to an apparatus and a method for flowing a gas into a processing chamber. More specifically, embodiments of the invention are directed to linear flow apparatus for directing a flow of gas to a processing chamber such as an atomic layer deposition chamber or chemical vapor deposition chamber.

In the field of semiconductor processing, flat-panel display processing or other electronic device processing, vapor deposition processes have played an important role in depositing materials on substrates. As the geometries of electronic devices continue to shrink and the density of devices continues to increase, the size and aspect ratio of the features are becoming more aggressive, e.g., feature sizes of 0.07 μm and aspect ratios of 10 or greater. Accordingly, conformal deposition of materials to form these devices is becoming increasingly important.

During an atomic layer deposition (ALD) process, reactant gases are introduced into a process chamber containing a substrate. Generally, a region of a substrate is contacted with a first reactant which is adsorbed onto the substrate surface. The substrate is then contacted with a second reactant which reacts with the first reactant to form a deposited material. A purge gas may be introduced between the delivery of each reactant gas to ensure that the only reactions that occur are on the substrate surface.

Gas distribution apparatus, sometimes shaped like and referred to as showerheads, distribute processing gases to a substrate (also referred to as a wafer) at close proximity. Gas distribution apparatuses, including showerheads, have large volumes which can be very difficult to clean or purge between gases. Any gases remaining in the showerhead may react with subsequent processing gases. For ALD processes, separation of gases is important within a gas distribution apparatus, including showerheads, that relies on alternating pulses of gases, for example, an A pulse, a B pulse, an A pulse, and a B pulse type delivery. Therefore, there is an ongoing need in the art for improved gas distribution apparatuses, including showerheads, that are easy to clean/purge and provide a uniform supply of gases to the substrate.

SUMMARY

One or more embodiments of the invention are directed to gas distribution apparatuses for controlling flow of gas into a process chamber. The apparatus comprises a delivery channel having an inlet end, an outlet end, a length and a plurality of apertures spaced along the length. An inlet on the inlet end of the delivery channel is connectable to a gas source, wherein flow of the gas is controllable by a gas valve in communication with the inlet. An outlet on the outlet end of the delivery channel is connectable to a vacuum source, wherein vacuum pressure through the outlet is controllable by an outlet valve to provide a reduced pressure at the outlet. A controller to regulate the flow of the gas through the delivery channel and into the process chamber by opening and closing the outlet valve during gas delivery and gas purging in the channel to control the flow of gas through the apertures along the length of the channel.

In some embodiments, a flow of gas through the gas distribution apparatus has a more uniform conductance along an axial length of the gas distribution apparatus than the flow of gas through a similar gas distribution apparatus without the vacuum source connected to the outlet. In one or more embodiments, when the gas valve is closed, the gas is purged from the delivery channel faster than a similar gas distribution apparatus without the vacuum source.

In some embodiments, the delivery channel is a recessed channel in a back side of a gas distribution plate and the plurality of apertures extend through the gas distribution plate to a front side of the gas distribution plate.

In one or more embodiments, the gas distribution plate is round and the delivery channel forms a spiral shape with one of the inlet end and outlet end is positioned in an outer peripheral region of the gas distribution plate and the other of the inlet end and outlet end positioned in a central region of the gas distribution plate. In some embodiments, the inlet end is positioned at the outer peripheral region of the gas distribution plate and the outlet end is positioned at the central region of the gas distribution plate. In one or more embodiments, the outlet end is positioned at the outer peripheral region of the gas distribution plate and the inlet end is positioned at the central region of the gas distribution plate.

In some embodiments, there are two delivery channels recessed in the back side of the gas distribution plate. In some embodiments, each of the delivery channels forms a spiral shape with one of the inlet end and outlet end positioned in an outer peripheral region of the gas distribution plate and the other of the inlet end and outlet end positioned in a central region of the gas distribution plate. In one or more embodiments, the two delivery channels are intertwined along the spiral shape. In certain embodiments, each delivery channel has the inlet end positioned in the outer periphery region of the gas distribution plate and the outlet end positioned in the central region of the gas distribution plate. In some embodiments, each delivery channel has the outlet end positioned in the outer periphery region of the gas distribution plate and the inlet end positioned in the central region of the gas distribution plate. In one or more embodiments, the inlet end of one delivery channel is positioned in the outer periphery region of the gas distribution plate and the outlet end of the other delivery channel is positioned in the outer periphery region of the gas distribution plate.

In some embodiments, the gas distribution apparatus further comprises a back cover on the back side of the gas distribution plate, the back cover covering the recessed channel. In one or more embodiments the delivery channel is a tubular spiral having a substantially planar configuration. In some embodiments, the gas distribution apparatus comprises a plurality of delivery channels, each delivery channel extending substantially straight and substantially parallel to adjacent delivery channels.

In one or more embodiments, more than one of the delivery channels are connected to the inlet so that a gas flowing through the inlet flows through each of the delivery channels. In some embodiments, each of the delivery channels connected to the inlet merge and are connected to one outlet. In some embodiments, each of the delivery channels connected to the inlet has a separate outlet connected to a separate outlet valve. In one or more embodiments, the controller independently adjusts each of the outlet valves to maintain a substantially uniform flow of gas through each of the delivery channels. In an embodiment, the plurality of delivery channels are shaped to form one or more of words or logos.

In some embodiments, the plurality of delivery channels are shaped so that the hole pattern seen by a substrate is uniform across the gas distribution apparatus.

Additional embodiments of the invention are directed to processing chambers comprising the gas distribution apparatus described. In some embodiments, the gas distribution apparatus comprises a tubular spiral having a substantially planar configuration, the gas distribution apparatus positioned between a substrate support and a gas distribution plate.

Additional embodiments of the invention are directed to gas distribution apparatus, comprising a gas distribution plate, a back cover, an inlet, an outlet and a controller. A gas delivery channel is recessed in a back side of a gas distribution plate. The recessed gas delivery channel has an inlet end, an outlet end, a length and a plurality of apertures spaced along the length extending through the gas distribution plate to a front side of the gas distribution plate so that gas flowing through the gas delivery channel can pass through the apertures exiting the gas distribution plate. The back cover is on the back side of the gas distribution plate covering the recessed channel. The inlet is connected to the inlet end of the gas delivery channel through the back cover. The inlet is connectable to a gas source, wherein a flow of gas is controllable by a gas valve in communication with the inlet. An outlet is connected to the outlet end of the gas delivery channel through the back cover. The outlet is connectable to a vacuum source, wherein vacuum pressure through the outlet is controllable by an outlet valve to provide a reduced pressure at the outlet. The controller regulates the flow of gas through the gas delivery channel and into a process chamber by opening and closing the outlet valve during gas delivery and gas purging to control the flow of gas through the apertures along the length of the channel.

In some embodiments, the gas distribution plate is round and the delivery channel forms a spiral shape with one of the inlet end and outlet end is positioned in an outer peripheral region of the gas distribution plate and the other of the inlet end and outlet end positioned in a central region of the gas distribution plate. In one or more embodiments, there are two delivery channels recessed in the back side of the gas distribution plate, the two delivery channels intertwined along the spiral shape.

Further embodiments of the invention are directed to gas distribution apparatuses comprising a plurality of elongate delivery channels. Each delivery channel extends from an inlet end along a length to an outlet end and has a plurality of apertures spaced along the length. The inlet end is connectable to a gas source, wherein flow of gas is controllable by a gas valve in communication with the inlet end. The outlet end is connectable to a vacuum source, wherein vacuum pressure through the outlet end is controllable by an outlet valve to provide a reduced pressure at the outlet end. A plurality of elongate vacuum channels with each channel extending along a length. A controller regulates the flow of gas through the gas delivery channel and into a process chamber by opening and closing the outlet valve during gas delivery and gas purging to control the flow of gas through the apertures along the length of the channel. The plurality of apertures of each delivery channel are separated from the plurality of apertures of an adjacent delivery channel by at least one elongate vacuum channel.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

FIG. 1 shows a view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 2 shows a view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 3 shows a view of a processing chamber including one or more gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 4 shows a top view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 5 shows a cross-section of a perspective view of a gas distribution apparatus in accordance with one or more embodiments of the invention

FIG. 6 shows a perspective view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 7 shows a bottom view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 8 shows a partial cross-sectional view of a gas distribution apparatus in accordance with one or more embodiments,

FIG. 9 shows a top view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 10 shows a partial cross-sectional view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 11 shows a view of an exploded partial cross-sectional view of a gas distribution apparatus in accordance with one or more embodiments of the invention

FIG. 12 shows a cross-section of a perspective view of a gas distribution apparatus in accordance with one or more embodiments of the invention

FIG. 13 shows a perspective view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 14 shows a bottom view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 15 shows a perspective view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 16A shows a partial cross-sectional view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 16B shows a partial cross-sectional view of a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 17 shows a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 18 shows a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 19 shows a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 20 shows a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 21 shows a gas distribution apparatus in accordance with one or more embodiments of the invention;

FIG. 22A shows a portion of a back side of a gas distribution apparatus in accordance with one or more embodiments of the invention; and

FIG. 22B shows the front side of the gas distribution apparatus ofFIG. 22A.

DETAILED DESCRIPTION

Embodiments of the invention are directed to gas distribution apparatus for use in chemical vapor deposition type processes. One or more embodiments of the invention are directed to atomic layer deposition processes and apparatus (also called cyclical deposition) incorporating the gas distribution apparatus described. The gas distribution apparatus described may be referred to as a showerhead or gas distribution plate, but it will be recognized by those skilled in the art that the apparatus does not need to be shaped like a showerhead or plate. The terms “showerhead” and “plate” should not be taken as limiting the scope of the invention.

A first embodiment of the invention is directed to an apparatus with a single spiral gas delivery channel. All gases flow sequentially through the same channel. An inlet is on the outer radial edge of the spiral, also referred to as the outer periphery, and may be attached to a gas source. A vacuum attachment is connected to the internal end of the spiral. The inlet and outlet can be reversed, either the gas source can be connected to the inside of the spiral with the outlet valve at the outside end of the spiral. The first embodiment can be used with a sequence as shown in Table 1.

TABLE 1

	Step	GasSource	Outlet Valve

	1	Precursor A	Closed
	2a	Purge	Closed
	2b	Purge	Open
	2c	Purge	Closed
	3	Precursor B	Closed

A second embodiment has two spiral channels intertwined. Each channel has a gas inlet on the outer radial end of the spiral and an outlet valve on the inner radial end of each spiral. The inlet and outlet can be reversed or mixed. The different channels can be used for different precursors.

In a third set of embodiments, the channel is a linear gas line. The linear gas line can take any suitable shape, not just linear. There can be multiple linear gas lines for different precursors. Some embodiments have multiple parallel paths for all gases in sequence, where conductance of the gas channels are substantially the same.

In one or more embodiments, in an individual channel, conductance of the gas through the channel and through the apertures is controlled by modulating or changing the vacuum pressure at the outlet end. Changing the vacuum pressure in turn creates a unique flow dynamic that cannot be achieved in conventional gas distribution apparatus. In some embodiments, a more uniform gas flow is provided along the length of each channel and through the apertures spaced along the length of the channel. A uniform gas flow according to one or more embodiments means that there is substantially no dead space that inhibits flow or pumping of gasses through the channel. The provision of a vacuum with or without a valve on one end of the channel with a valve at the other end of the channel permits rapid switching between different types of gases, such as precursor or reactant gases.

In some embodiments, the vacuum at the end of the gas delivery channel enables the rapid purging of gases from within the channel. A purge gas source can be connected to the inlet of the gas delivery channel and work cooperatively with the vacuum at the outlet of the channel to even more rapidly remove the reactive gases from the channel. Additionally, vacuum ports can be spaced along the length of the gas delivery channel, not just at the end of the channel.

Embodiments of the invention may be capable of increasing the conductance of gas through the holes spaced along the gas delivery channel. Without being bound by any particular theory of operation, it is believed that controlling the vacuum pressure at the outlet end, or in the middle, of the channel changes the flow dynamics relative to a conventional showerhead or gas distribution plate.

Referring toFIGS. 1 and 2, one or more embodiments are directed togas distribution apparatus100 to deliver a gas to a process chamber (not shown). Thegas distribution apparatus100 comprises adelivery channel102 with aninlet end104 and anoutlet end106. Thedelivery channel102 has a plurality ofapertures108 spaced along the length of thedelivery channel102. Aninlet110 is connected to and in fluid communication with theinlet end104 of thedelivery channel102. Anoutlet112 is connected to and in fluid communication with theoutlet end106 of thedelivery channel102. Theinlet110 is adapted to be connected to a gas source and may include aninlet valve114 capable of controlling the flow of gas into (or out of) thedelivery channel102 or completely cut off the flow of gas. Theoutlet112 is adapted to be connected to a vacuum source and may include anoutlet valve116 capable of controlling the flow of gas into (or out of) thedelivery channel102 or completely cut off the flow of gas. Theoutlet112 is connectable to a vacuum source (not shown) so that vacuum pressure through theoutlet112 is controllable by theoutlet valve116 to provide a reduced pressure at theoutlet112.

Acontroller150 regulates the flow of the gas through thedelivery channel102 and into the process chamber. Thecontroller150 does this by opening or closing (or any point in between fully open and fully closed) the outlet valve during gas delivery and gas purging. This controls the flow of gas through apertures (seen, for example, inFIG. 4) spaced along the length of the channel.

The cross-sectional shape of thedelivery channel102 can be controlled such that gas flowing through the delivery channel experiences minimal resistance to flow. In some embodiments, thedelivery channel102 has a round or oval cross-sectional shape. In one or more embodiments, thedelivery channel102 has a cross-sectional shape sufficient such that bends, turns, twists, etc. provide substantially no dead space.

The overall shape (as opposed to the cross-sectional shape) of thedelivery channel102 can be modified as desired. For example, thedelivery channel102 can be shaped to fit within specific areas or to match the shape of a substrate. Thedelivery channel102 can be, for example, straight, round, square, oval, rectangular or oblong. Additionally, the overall shape of the delivery channel can be made up of repeating units, parallel, perpendicular or concentric to each other. In one or more embodiments, the delivery channel has an overall shape in which there is substantially no dead space to inhibit gas flow or purging. As used in this specification and the appended claims, the term “substantially no dead space” means that the flow of gas, or purging, is inhibited by less than about 10% or by less than about 5% due to dead space.

In some embodiments, thedelivery channel102 is a tubular spiral having a substantially planar configuration. This particular shape is exemplified by the embodiment shown inFIGS. 1 and 2. As used in this specification and the appended claims, the term “substantially planar configuration” means that the plurality ofapertures108 in thedelivery channel102 are in mostly the same plane. The embodiment shown inFIGS. 1 and 2 has a substantially planar configuration because the apertures are coplanar, even though the inlet end and outlet end, and the portions of the delivery channel near the inlet end and outlet end are not coplanar with the plurality of apertures.

Thedelivery channel102 can be used for plasma processing. For example, thedelivery channel102 can be polarized relative to another portion of the processing chamber to ignite a plasma within the chamber. Thedelivery channel102 can be biased relative to a portion of the chamber, or a portion of the chamber can be biased relative to thedelivery channel102. For example, thedelivery channel102 can be polarized relative to the pedestal, or the pedestal can be polarized relative to the delivery channel. The frequency of the plasma can be tuned as well. In one or more embodiments, the plasma is at a frequency of about 13.56 MHz. In some embodiments, the plasma is at a frequency of about 40 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, 100 MHz, 110 MHz or 120 MHz.

Any suitable material can be used for the delivery channel, showerhead or gas distribution apparatus. Suitable materials include, but are not limited to stainless steel and inert materials. In some embodiments, the delivery channel, showerhead or gas distribution plate is made of stainless steel.

FIG. 3 shows a cross-section of a portion of a processing chamber according to one or more embodiments. Agas distribution apparatus100 is placed between asubstrate support pedestal302 and agas distribution plate306. Thesubstrate support pedestal302 is shown supporting asubstrate304. Thesubstrate support pedestal302 can be stationary or rotating, or can be stationary for part of the processing and rotating for part of the processing. Arotating support pedestal302 may allow for more uniform processing of a substrate by minimizing different gas flow patterns that may occur throughout the processing chamber. Thesupport pedestal302 of some embodiments includes a heater or heating mechanism. The heater can be any suitable type of heater including resistive heaters.

Thegas distribution apparatus100 is shown as a tubular spiral with a substantially planar configuration. Thesubstrate304 can be processed with either, or both, thegas distribution plate306 and thegas distribution apparatus100. Thegas distribution apparatus100 can be shaped so that it does not substantially interfere with gas flowing from thegas distribution plate306. As used in this specification and the appended claims, the term “substantially interfere” means that thegas distribution apparatus100 does not interfere with more than about 30% of the gas flowing from the gas distribution plate. For example, thefront surface308 of thegas distribution plate306 has a plurality ofapertures310 through which gases flow. Thegas distribution apparatus100 can be shaped to avoid blocking theapertures310.

The delivery channel positioned like that ofFIG. 3 can also be used for plasma processing. Theapparatus100 can be polarized relative to a portion of the chamber, or a portion of the chamber can be polarized relative to theapparatus100. For example, thedelivery channel apparatus100 can be polarized relative to thepedestal302, or thepedestal302 can be polarized relative to theapparatus100. In some embodiments, theapparatus100 is polarized relative to thegas distribution plate306. In one or more embodiments, thegas distribution plate306 is polarized relative to thepedestal302 and gas flowing from theapparatus100 forms the plasma. The frequency of the plasma can be tuned as well. In one or more embodiments, the plasma is at a frequency of about 13.56 MHz. In some embodiments, the plasma is at a frequency of about 40 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, 100 MHz, 110 MHz or 120 MHz.

FIGS. 4 through 7 show another embodiment of agas distribution apparatus400 in which thedelivery channel402 is a recessed channel in theback side401 of agas distribution plate403. The embodiment shown has a large inner section is recessed in theback side401 of thegas distribution plate403 with thedelivery channel402 recessed even further. This allows for the addition of aback cover407 which can be placed in the recessed area in theback side401 enclosing thedelivery channel402. Theback cover407, when inserted into the recessed backside401 of certain embodiments creates a substantially flush back side surface of the gas distribution plate. It will be understood by those skilled in the art that theback cover407 does not need to fit within a recessed area of theback side401 of thegas distribution plate403, but can also rest directly on theback side401 of thegas distribution plate403. In embodiments of this sort, there is no large recessed area with the delivery channels being further recessed. Instead, the delivery channels are recessed directly into theback side401 of thegas distribution plate403.

Theback cover407 may have openings to allow for the passage of inlet and outlet tubes to allow for fluid communication with thedelivery channel402. This can be seen inFIGS. 5 and 6. The inlet and outlet tubes can be an integral part of theback cover407, or can be separate pieces connected to theback cover407 in such a manner as to prevent or minimize fluid leakage. A plurality ofapertures408 extend through thegas distribution plate403 to afront side405 of thegas distribution plate403. These apertures can be seen inFIGS. 4, 5 and 7. The plurality ofapertures408 can be evenly spaced along the length of the delivery channel, or can have varied spacing along the length of the channel. Variable spacing may help produce a more uniform gas flow from the delivery channel at points along the delivery channel. For example, in gas delivery channel that has an elaborate shape, the spacing of the apertures can varied along the length.

InFIGS. 5 and 6, theinlet end404 and outlet end406 are illustrated as a small tube extending from theback cover407 of thegas distribution plate403. The tubes extend between theinlet410 and theback cover407 through aninlet valve414. Another tube can extend between theoutlet412 and theback cover407 through theoutlet valve416. The tubes can be connected to theback cover407 by any suitable connection known to those skilled in the art and may be sealed to prevent leakage of fluid flowing through the tube into thedelivery channel402. Suitable sealing devices include, but are not limited to, o-rings positioned between aflange424 and theback cover407. Theflange424 can be integrally formed with the tube or can be a separate piece that holds the tube to the back cover. Theflange424 can be connected to theback cover407 by any suitable mechanical connection, including but not limited to, screws.

FIG. 8 shows a cross-sectional view of one portion of adelivery channel402 and anaperture408 in agas distribution plate403 in accordance with one or more embodiments of the invention. It will be understood by those skilled in the art that the delivery channel and apertures described inFIG. 8 are merely illustrative and should not be taken as limiting the scope of the invention. Those skilled in the art will understand that there are other ways of creating flow from thedelivery channel402 through thegas distribution plate403. Thedelivery channel402 shown inFIG. 8 has two portions, anupper portion832 and alower portion830. While these portions are shown as separate areas, it will be understood that there can be a seamless transition between theupper portion832 and the roundedlower portion830.

Additionally, it will be understood that theupper portion832 is optional and does not need to be included in thedelivery channel402. When there is noupper portion832, thelower portion830 is the only portion. Thus, the delivery channel can have any suitable shape. In some embodiments, the shape of the delivery channel is such that there is substantially no interference with the flow of gases through the channel.

Theupper portion832 can have my suitable shape. In the embodiment shown inFIG. 8, theupper portion832 has walls which extend normal to the surface of theback side401 of thegas distribution plate403. However, it will be understood that theupper portion832 can have walls which are canted from square to theback side401. The canting can provide a larger opening at theback side401 of thegas distribution plate403, tapering to a smaller opening. Additionally, the canting can provide a smaller opening at theback side401, tapering to a larger opening. The length of theupper portion832 can be modified as necessary.

In some embodiments, the upper portion has sides which are substantially perpendicular to theback side401 of thegas distribution plate403 and extend a length L below the surface of theback side401 in the range of about 0.01 inch to about 0.3 inches. As used in this specification and the appended claims, the term “substantially perpendicular to” means that walls of the upper portion have an angle relative to the back side of the gas distribution plate in the range of about 85 degrees to about 95 degrees. In some embodiments, the upper portion extends below the surface of the back side to a length L in the range of about 0.02 inches to about 0.2 inches, or in the range of about 0.05 inches to about 0.15 inches, or in the range of about 0.08 inches to about 0.12 inches. In one or more embodiments, the upper portion extends below the surface of the back side to a length about 0.1 inches.

The roundedlower portion830 can have any suitable cross-section including, but not limited to, half-round and half-elliptical. The width of the rounded lower portion, also referred to as the diameter of the rounded lower portion, can be modified as necessary. The width of the upper portion can be modified as necessary. The diameter of the delivery channel, in general, can have an impact of the number of loops in the spiral. In some embodiments, as shown inFIG. 8, the width of the upper portion is about equal to the diameter of the lower portion. The delivery channel of various embodiments has a diameter in the range of about 0.3 inches to about 0.45 inches, or in the range of about 0.325 inches to about 0.425 inches, or in the range of about 0.35 inches to about 0.40 inches. In one or more embodiments, the delivery channel has a diameter of about 0.375 inches.

The specific shape of theapertures408 can vary depending on the desired flow of gases through the apertures. In the embodiment ofFIG. 8, theaperture408 has three distinct sections; afirst section834, asecond section836 and athird section838. Again, the number of sections and the shape of the sections are merely illustrative of one embodiment and should not be taken as limiting the scope of the invention. Thefirst section834 extends from the roundedlower portion830 of thedelivery channel402 toward thefront side405 of thegas distribution plate403. Thefirst section834 has a first diameter D1. Thesecond section836 extends from thefirst section834 toward thefront side405 and has a diameter which tapers from the first diameter D1 to a second diameter D2, which is generally smaller than the first diameter. Thethird section838 extends from the end of thesecond section836 and ends at thefront side405 of thegas distribution plate403. At the intersection of thethird section838 and thefront side405, ahole840 is formed. Gases flowing through thedelivery channel402 exit thegas distribution plate403 through thishole840 into the processing chamber. Thehole840 has about the same diameter as the second diameter D2. In various embodiments, the diameter of thehole840 is in the range of about 0.01 inches to about 0.25 inches, or in the range of about 0.02 inches to about 0.2 inches, or in the range of about 0.03 inches to about 0.15 inches or in the range of about 0.04 inches to about 0.1 inches. In some embodiments, thehold 840 has a diameter less than about 0.1 inches, or less than about 0.08 inches, or less than about 0.06 inches, or less than about 0.04 inches, or less than about 0.02 inches, or less than about 0.01 inch.

As the delivery channel spirals from the outer peripheral edge of the gas distribution plate to the central region, or vice versa, a seeming plurality of adjacent channels are observable in cross-section, even though it may be a single channel.FIG. 5 shows this seeming plurality of channels. The channels, or separation between loops of the spiral, are separated by a distance. In some embodiments, the distance between the channels, or the loops of the single channel, measured from centers, are in the range of about 0.375 inches to about 0.475 inches, or in the range of about 0.40 inches to about 0.45 inches, or in the range of about 0.41 inches to about 0.43 inches. In one or more embodiments, the average distance between centers of the adjacent channels is about 0.42 inches.

The length of the gas channel shown inFIGS. 4 to 7 can vary depending on a number of factors, including, but not limited to, the diameter of the channel and the distance between the adjacent channels. In various embodiments, the delivery channel has a length in the range of about 140 inches to about 340 inches, or in the range of about 180 inches to about 300 inches, or in the range of about 200 inches to about 280 inches, or in the range of about 220 inches to about 260 inches. In one or more embodiments, the delivery channel has a length of about 240 inches.

The number of apertures are also dependent on a number of factors, including but not limited to, the length of the delivery channel and the spacing of the apertures. In some embodiments having a single spiral channel, there are in the range of about 300 and 900 apertures, or in the range of about 400 to about 800 apertures, or in the range of about 500 to about 700 apertures. In various embodiments, there are greater than about 300, 400, 500, 600, 700 or 800 apertures along the length of the channel. In one or more embodiments, there are about 600 apertures along the length of the delivery channel.

In an embodiment, as shown inFIG. 4, thegas delivery plate403 comprises asingle delivery channel402 in a back side of thegas delivery plate403. Thedelivery channel402 has aninlet end404 located in an outerperipheral region420 of thegas distribution plate403. Thedelivery channel402 and follows an inward spiral path from theinlet end404 to anoutlet end406 located in acentral region422 of thegas distribution plate403. Thedelivery channel402 has an overall length, defined as the distance between theinlet end404 and theoutlet end406 of about 240 inches. A plurality ofapertures408 are spaced along the overall length of thedelivery channel402. Along the overall length of thedelivery channel403 there are in the range of about 500 apertures and about 700 apertures. Thedelivery channel403 has an average diameter of about 0.375 inches and adjacent portions of the spiral channel are spaced about 0.42 inches on center.

Some embodiments of the invention include more than onedelivery channel402. These multiple channels can be intertwined or separate depending on the needs of the processing system. Some channels can be recessed into a gas distribution plate as shown inFIG. 4, or can be individual tubes as shown inFIG. 1. In some embodiments, there are a combination of individual tubes and recessed channels. An exemplary embodiment of the sort is shown inFIG. 3, where the gas distribution plate may have at least one recessed delivery channel therein and an additional delivery channel is positioned between the gas distribution plate and the substrate surface.

Another embodiment of the invention is shown inFIGS. 9 through 14. Agas distribution apparatus900 comprises two

delivery channels

902a,902b recessed in theback side901 of agas distribution plate903. It will be understood that the delivery channels do not need to be recessed into the back of a gas distribution plate, but can be individual tubes, as shown inFIGS. 1 and 15. Thefirst delivery channel902a has afirst inlet end904a and afirst outlet end906a and a plurality offirst apertures908a spaced along the length of thefirst delivery channel902a. Thesecond delivery channel902b has asecond inlet end904b, asecond outlet end906b and a plurality ofsecond apertures908b spaced along the length of thesecond delivery channel902b.

Afirst inlet910a is connected to thefirst inlet end904a of thefirst delivery channel902a. Thefirst inlet910a is adapted to be connected to a gas source. Afirst outlet912a is connected to thefirst outlet end906a of thefirst delivery channel902a. Thefirst outlet912a is adapted to be connected to a vacuum source. Asecond inlet910b is connected to thesecond inlet end904b of thesecond delivery channel902b. Thesecond inlet910b is adapted to be connected to a gas source. Asecond outlet912b is connected to thesecond outlet end906b of thesecond delivery channel902b. Thesecond outlet912a is adapted to be connected to a vacuum source.

In the embodiment shown inFIGS. 9 to 14, each of the

delivery channels

902a,902b form a spiral shape. One or more embodiments, as that shown in the Figures, have the two

delivery channels

902a,902b intertwined along the length of the spiral shape. It will be understood by those skilled in the art that the two

delivery channels

902a,902b can have shapes other than spiral and do not need to intertwine. In certain embodiments, the plurality offirst apertures908a andsecond apertures908b extend through thegas distribution plate903 to thefront side905 of thegas distribution plate903.

In some embodiments, each of the

delivery channels

902a,902b form a spiral shape with one of the

inlet end

904a,904b and

outlet end

906a,906b positioned in an outerperipheral region920 of thegas distribution plate903 and the other of the

inlet end

904a,904b and

outlet end

906a,906b positioned in a central region922 of thegas distribution plate903. In one or more embodiments, the inlet ends904a,904b of both

channels

902a,902b is positioned in the outerperipheral region920 and the inlet ends904a,904b of both

channels

902a,902b are positioned in the central region922 of thegas distribution plate903. In certain embodiments, the inlet ends904a,904b of both

channels

902a,902b is positioned in the central region922 and the inlet ends904a,904b of both

channels

902a,902b are positioned in the outerperipheral region920 of thegas distribution plate903. In one or more embodiments, one or the inlet ends904a,904b is positioned in the outerperipheral region920 and the

other inlet end

904b,904a is positioned at the central region922, with the outlet ends906a,906b at the other end of each

individual delivery channel

902a,902b.

FIG. 11 shows aback cover907 for thegas distribution plate903 shown inFIG. 9. There are four holes (not numbered) located in theback cover907 which align approximately with the inlet ends904a,904b and outlet ends906a,906b of the

delivery channels

902a,902b. The holes can be used to provide an access point for connected in the

inlet

910a,910b and

outlet

912a,912b to the

channels

902a,902b. In some embodiments, there

inlet

910a,910b and

outlet

912a,912b are integrally formed with theback cover907. Additionally, as seen inFIGS. 12 and 13, there can be one or

more inlet valves

914a,914b and

outlet valves

916a,916b

FIGS. 12 and 13 show perspective views of agas distribution apparatus900 in accordance with various embodiments of the invention. The

inlets

910a,910b are shown connected to theback cover907 with aflange924a,924b. The connection and gas-tight sealing of theflange924a,924b can be accomplished by any suitable mechanism and techniques as known to those skilled in the art. The

outlets

912a,912b can also be connected to theback cover907 with a flange or with ablock connection925. Theblock925 can be integrally formed with theback cover907 or can be a separate piece. Theblock925 may provide additional support and space for the

outlet valves

916a,916b, allowing the connecting tubes to protrude from theback cover907 at an angle. Although the

inlets

910a,910b and

inlet valves

914a,914b are shown on the outsideperipheral region920 of thegas distribution plate903 and the

outlets

912a,912b and

outlet valves

916a,916b are shown at the central region922 of thegas distribution plate903, it will be understood that these components can be reversed or intermixed and that the drawings are merely illustrative of one embodiment.

As the delivery channels spiral from the outer peripheral edge of the gas distribution plate to the central region, or vice versa, a seeming plurality of adjacent channels are observable in cross-section. With the spirals intertwined, the gas in every adjacent channel is from the

other inlet

910a,910b. The channels are separated by a distance from the adjacent channels. In some embodiments, the distance between the channels, measured from the center of the channel, are in the range of about 0.375 inches to about 0.475 inches, or in the range of about 0.40 inches to about 0.45 inches, or in the range of about 0.41 inches to about 0.43 inches. In one or more embodiments, the average distance between centers of the adjacent channels is about 0.42 inches.

The length of the gas channel shown inFIGS. 9-14 can vary depending on a number of factors, including, but not limited to, the diameter of the channel and the distance between the adjacent channels. In various embodiments, each of the delivery channels has a length in the range of about 70 inches to about 170 inches, or in the range of about 90 inches to about 150 inches, or in the range of about 100 inches to about 140 inches, or in the range of about 110 inches to about 130 inches. In one or more embodiments, the delivery channel has a length of about 120 inches.

The number of apertures are also dependent on a number of factors, including but not limited to, the length of the delivery channel and the spacing of the apertures. In some embodiments having a single spiral channel, there are in the range of about 150 and 450 apertures, or in the range of about 200 to about 400 apertures, or in the range of about 250 to about 350 apertures. In various embodiments, there are greater than about 150, 200, 250, 300, 350 or 400 apertures along the length of the channel. In one or more embodiments, there are about 300 apertures along the length of each of the delivery channels.

The apparatus shown inFIGS. 4 through 14 can be used for plasma processing. For example, the delivery channel, gas distribution apparatus or showerhead can be polarized relative to another portion of the processing chamber to ignite a plasma within the chamber. The delivery channel, gas distribution apparatus or showerhead can be polarized relative to a portion of the chamber, or a portion of the chamber can be biased relative to the delivery channel, gas distribution apparatus or showerhead. For example, the delivery channel, gas distribution apparatus or showerhead can be polarized relative to the pedestal, or the pedestal can be polarized relative to the delivery channel, gas distribution apparatus or showerhead. The frequency of the plasma can be tuned as well. In one or more embodiments, the plasma is at a frequency of about 13.56 MHz. In some embodiments, the plasma is at a frequency of about 40 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, 100 MHz, 110 MHz or 120 MHz.

In some embodiments of the apparatus exemplified byFIGS. 4 through 14, there is an insulating material (not shown) positioned between the back cover and the main body portion of the gas distribution apparatus (i.e., the portion including the gas delivery channel). This insulating material provides electrical isolation between the back cover and the main body portion of the gas distribution apparatus so that the back cover can be polarized relative to the main body portion. Doing so may allow for the ignition of a plasma within the gas distribution apparatus, or within the delivery channels. The plasma can then be flowed through the plurality of apertures into the processing region of the processing chamber, the processing region being the region between the gas distribution apparatus and the pedestal. This configuration may be referred to as a remote plasma because the plasma is formed (e.g., ignited) outside of the processing region.

FIGS. 15, 16A and 16B show another exemplary embodiment of agas distribution apparatus1500. The gas distribution apparatuses shown are particularly useful for spatially separated atomic layer deposition processes in which different portions of the substrate are simultaneously exposed to different deposition gases and thesubstrate1544 is moved relative to the gas distribution apparatus so that all parts of the substrate are exposed sequentially to each of the deposition gases. In these embodiments, thegas distribution apparatus1500 comprises a plurality ofdelivery channels1502, eachdelivery channel1502 extending substantially straight and substantially parallel to adjacent delivery channels. Each of thedelivery channels1502 has aninlet end1504 and anoutlet end1506 with a plurality of spacedapertures1508 there between.

The gas distribution apparatus shown inFIGS. 15, 16A and 16B have a plurality ofelongate delivery channels1502 and a plurality ofelongate vacuum channels1550. Each of thedelivery channels1502 andvacuum channels1550 are connected to aoutput channel1552 at the front face of the gas distribution apparatus. Each of thedelivery channels1502 is adapted to flow one or more of a reactive gas and a purge gas. Eachdelivery channel1502 is connected to anoutput channel1552 by a plurality of spacedapertures1508. Each of thevacuum channels1550 is connected to aninlet channel1554 by a plurality of spacedvacuum apertures1558. The plurality ofapertures1508 of eachdelivery channel1502 are separated from the plurality ofapertures1508 of eachadjacent delivery channel1502 by at least one plurality ofvacuum apertures1558 from avacuum channel1550.

In the embodiment shown inFIG. 16A, each of the central vacuum channels1550 (not the end vacuum channels) are connected to twoinlet channels1554 byvacuum apertures1508. Theend vacuum channels1550 are only connected to asingle inlet channel1554. It should be understood that this is merely exemplary and should not be taken as limiting the scope of the invention. Eachinlet channel1554 can have a dedicatedvacuum channel1550, or asingle vacuum channel1550 can be connected to more than twoinlet channels1554 through a plurality ofvacuum apertures1508.

While each of the delivery channels appear the same, there can be a different gas flowing through each. For example, purge channels (denoted P) may have a purge gas flowing there through, each of the first reactive gas channels (denoted A) may have a first reactive gas flowing there through and each of the second reactive gas channels (denoted B) may have a second reactive gas flowing there through. The vacuum channels (denoted V) are connected to a vacuum source. With reference toFIG. 16A, a substrate1544 (or more specifically, a fixed point on a substrate) moving from left to right would encounter in order a vacuum gas channel, a purge gas channel, a vacuum gas channel, a first reactive gas channel, a vacuum gas channel, a purge gas channel, a vacuum gas channel, a second reactive gas channel, a vacuum gas channel, etc., depending on the size of the gas distribution plate.

The use of the delivery channels with inlet and outlet ends allows for the rapid exchange of gas within the delivery channel. For example, after the substrate (or fixed point on the substrate) is exposed to the second reactive gas channel (denoted B), the outlet end of the delivery channel can be opened, allowing the gas within the channel to be removed, and a different reactive gas (e.g., gas C) can then be flowed into the delivery channel. Thus, when the substrate passes back under that gas channel the substrate will be exposed to gas C instead of gas B. While this example has been made with respect to a second reactive gas, it will be understood by those skilled in the art that an of the gas delivery channels (first reactive gas, second reactive gas or purge gas) can be purged and replaced with a different gas.

The delivery channel ofFIGS. 15, 16A and 16B can be used for plasma processing as well. Thegas distribution apparatus1500 can be biased relative to another portion of the chamber. For example, thegas distribution apparatus1500 can be polarized relative to the pedestal, or the pedestal can be polarized relative to the gas distribution apparatus. The frequency of the plasma can be tuned as well. In one or more embodiments, the plasma is at a frequency of about 13.56 MHz. In some embodiments, the plasma is at a frequency of about 40 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, 100 MHz, 110 MHz or 120 MHz.

FIG. 16B shows an embodiment of asingle delivery channel1502 and asingle vacuum channel1550. Each of thedelivery channel1502 andvacuum channel1550 have two sets of apertures extending therefrom. In the case of thevacuum channel1550, one set ofapertures1558a connect to afirst inlet channel1554a and the other set ofapertures1558b connects to asecond inlet channel1554b. Thedelivery channel1502, on the other hand, has two sets ofapertures1508 extending to asingle output channel1552.

TABLE 2

		Intermediate
Step	Gas Source	Outlet valve	Outlet valve

1a	Precursor A	Closed	Partially Open
1b	Precursor A	Closed	Closed
2a	Purge	Open	Closed
2b	Purge	Open	Open
2c	Purge	Open	Closed
3a	Precursor B	Partially Open	Closed
3b	Precursor B	Closed	Closed

The valves shown in Table 2 are open, closed or partially open at any point during the processing. In Step3a, after purging the delivery channel of Precursor A, the intermediate outlet valve is partially open to accelerate the flow of Precursor B through the delivery channel and then closed in Step3b. This is merely one possible sequence that can be used and should not be taken as limiting the scope of the invention.

The embodiment shown inFIG. 17 effectively includes two outlets, one at the end of the delivery channel and one in the middle. Those skilled in the art will understand that there can be any number of outlets spaced along the length of the delivery channel and at any position along the length of the channel. For example, theintermediate outlet1740 could be positioned at ⅓ of the length of the channel. Additionally, there can be any number of outlets. For example, the delivery channel may have four outlets, one at the end and one positioned at each of ¼, ½ and ¾ of the length of the delivery channel. In another example, the delivery channel includes four outlets, one at the end and one position at each of ¼, ¾ and 9/10 of the length of the delivery channel. In some embodiments, the delivery channel includes 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11 total outlets (including an outlet at the outlet end of the channel).

FIG. 18 shows another embodiment of the invention in which thegas distribution apparatus1800 includes amultipath delivery channel1802. Here, theapparatus1800 includes adelivery channel1802 with aninlet end1804 and anoutlet end1806. Aninlet1810 is connected to and in communication with theinlet end1804 of thedelivery channel1802. Anoutlet1812 is connected to and in communication with theoutlet end1806 of thedelivery channel1802. Theinlet1810 is connectable to a gas source (not shown) and may include aninlet valve1814 that can control the flow of gas into (or out of) thedelivery channel1802 or completely cut off the flow of gas. Theoutlet1812 is connectable to a vacuum source (not shown) and may include anoutlet valve1816 that can control the flow of gas out of (or into) thedelivery channel1802 or completely cut off the vacuum source from thedelivery channel1802. Thedelivery channel1802 splits near theinlet end1804 into three

separate channels

1802a,180b,1802c and merges back into a single channel near theoutlet end1806. A plurality ofapertures1808 are spaced along the length of each of the channels so that a single gas flowing into theinlet1810 can be directed along multiple paths and connected to asingle outlet1812. Theapertures1808 can be evenly spaced or unevenly spaced along the length of thechannel1802.

The embodiment shown splits the delivery channel into three separate channels along the length of the channel. However, it will be understood by those skilled in the art that this is merely exemplary and that the delivery channel can be split into any number of channels. In some embodiments, the delivery channel splits into 2, 3, 4, 5, 6, 7, 8, 9 or 10 separate delivery channels. Additionally, the delivery channel can split multiple time along the length of the channel. For example, the channel can split into two, merge into one and then split into 3 along the length of the channel.

The flow of gas through the multi-channel gas distribution apparatus shown inFIG. 18 may not be uniform among the three channels. The uniformity of gas flow between the channels can be affected by a number of factors including, but not limited to, gas pressure, vacuum pressure, temperature, flow rate and from static pressure drops along the length.FIG. 19 shows another embodiment of agas distribution apparatus1900 in which thedelivery channel1902 splits into three

separate channels

1902a,1902b,1902c each with its

own outlet valve

1912a,1912b,1912c. Theapparatus1900 shown includes aninlet end1904 connected through aninlet valve1914 to aninlet1910. Thedelivery channel1902 includes a plurality ofapertures1908 spaced along the length of each of the

separate channels

1902a,1902b,1902c. The apertures can be evenly spaced or unevenly spaced along the length of the channels. Each channel has a

separate outlet

1912a,1912b,1912c withseparate outlet valves1916a,1916b,1916c. Each of theoutlet valves1916a,1916b,1916c is connected to acontroller1950 that can independently control each of theoutlet valves1916a,1916b,1916c. In this embodiments, thecontroller1950 can set the outlet valves to closed, fully open, or at any point in between. For example, if the flow of gas through one of the channels is lower than the others, thecontroller1950 may open the outlet valve of that channel to accelerate the flow or may open the outlet valves of the other channels to accelerate flow and cause less gas to exit the channels through the apertures to cause a more uniform flow.

Multiple separate channels can also be employed.FIG. 20 shows an embodiment of agas distribution apparatus2000 with five separate

gas delivery channels

2002a,2002b,2002c,2002d,2002e. Each of the

delivery channels

2002a,2002b,2002c,2002d,2002e includes an

inlet valve

2014a,2014b,2014c,2014d,2014e and an

outlet valve

2016a,2016b,2016c,2016d,2016e. Four spiral shapeddelivery channels2002a-d are shown leaving avoid area2060 at the center of the four channels. The fifth delivery channel2002e passes between the spirals and oscillates in thevoid area2060 to prevent dead space in the gas flow. The fifth delivery channel2002e is shown with anintermediate outlet valve2044. Each of the delivery channels can be configured to deliver the same gas, or can deliver separate gases.

In one embodiment, the five channels cover a single substrate and each channel delivers the same reactive gas. The substrate may be rotated beneath the delivery channels, or the channels may rotate or oscillate over the substrate. In another embodiment, alternative delivery channels (e.g.,2002a,2002c) can deliver a first reactive gas and the other channels (e.g.,2002b,2002d) can deliver a second reactive gas. The fifth channel2002e can be configured to deliver an inert gas to form a curtain between the separate channels to separate the gases and prevent gas-phase reactions. Rotating the substrate beneath these channels would expose alternating quarters to the same gas followed by the second reactive gas to deposit a film. In this embodiment, the portion of the substrate in thevoid area2060 would not have a deposited layer.

In another embodiment, each of the channels can deliver the same gas but be sized so that a single substrate would be covered by a single delivery channel allowing the processing of multiple substrates by moving the substrates from one delivery channel to the adjacent channel. Each channel can be configured to deliver the same gas or separate gases and the fifth channel can be configures to deliver an inert gas to form a curtain separating the reaction regions adjacent the delivery channels. The fifth delivery channel, and any other gas delivery channel described herein can have multiple inlets and a single outlet, or multiple outlets. For example the fifth delivery channel shown may have an inlet at either end and a single outlet in the middle to create a stronger gas curtain to separate the other delivery channels.

Again, the shape and number of outlets can vary depending on the desired use. The spiral shape shown inFIG. 20 is merely exemplary and should not be taken as limiting the scope of the invention. The shape of the gas delivery channel(s) can be modified for a number of reasons. In some embodiments, the gas delivery channel is shaped for spell words (e.g., “Applied Materials”) or form a logo. For example,FIG. 21 shows three

delivery channels

2102a,2102b,2102c roughly forming the logo of Applied Materials, Inc. of Santa Clara, Calif. The firstgas delivery channel2102a and secondgas delivery channel2102b each have a

single inlet valve

2114a,2114b and a

single outlet valve

2116a,2116b. The thirdgas delivery channel2102c has asingle inlet valve2114c and two

outlet valves

2116c,2116d. Along the length, the thirdgas delivery channel2102c splits into two channels, reforms into a single channel and then splits into two channels again. In another embodiment, inlet valves and outlet valves of the third delivery channel are reversed so that there are two inlet valves and a single outlet valve.

The gas flows coming from the surface of the gas distribution apparatus seen by the substrate can be uniform or striated. For example, a substrate passing beneath the dual spiral gas distribution apparatus shown inFIG. 9 will see alternating rings of gases. In some embodiments, the plurality of delivery channels are shaped so that the hole pattern seen by a substrate is uniform across the gas distribution apparatus.FIGS. 22A and 22B show part an embodiment of agas distribution apparatus2203 in which the gas flows seen by a substrate would be uniform.FIG. 22A shows theback side2201 of agas distribution apparatus2203 with a plurality of alternating

gas channels

2202a,2202b. The

gas channels

2202a,2202b undulate with the

holes

2208a,2208b spaced along the length of the gas channels so thathole2208 pattern seen on thefront side2205 inFIG. 22B is uniform. Additionally, the gas flows seen by the substrate are uniform because there is a uniform distribution of holes across the gas distribution apparatus front. Looking atFIG. 22B, the top row ofholes2208 would alternate between the first gas and the second gas, with the next row having the reverse pattern. Thus, of the twelveholes2208 shown, the first gas will flow out of six of the holes and the second gas will flow out of the other six holes.

There can be

multiple inlet valves

2214a,2214b, as shown inFIG. 22A, or can be a single valve split into multiple channels. Additionally, there can be

multiple outlet valves

2216a,2216b, as shown inFIG. 22B, or there can be a single outlet valve joining each of the channels.

The gas distribution apparatus described can be used to form one or more layers during a plasma enhanced atomic layer deposition (PEALD) process. In some processes, the use of plasma provides sufficient energy to promote a species into the excited state where surface reactions become favorable and likely. Introducing the plasma into the process can be continuous or pulsed. In some embodiments, sequential pulses of precursors (or reactive gases) and plasma are used to process a layer. In some embodiments, the reagents may be ionized either locally (i.e., within the processing area) or remotely (i.e., outside the processing area). Remote ionization can occur upstream of the deposition chamber such that ions or other energetic or light emitting species are not in direct contact with the depositing film. In some PEALD processes, the plasma is generated external from the processing chamber, such as by a remote plasma generator system. The plasma may be generated via any suitable plasma generation process or technique known to those skilled in the art. For example, plasma may be generated by one or more of a microwave (MW) frequency generator or a radio frequency (RF) generator. The frequency of the plasma may be tuned depending on the specific reactive species being used. Suitable frequencies include, but are not limited to, 2 MHz, 13.56 MHz, 40 MHz, 60 MHz and 100 MHz. Although plasmas may be used during the deposition processes disclosed herein, it should be noted that plasmas may not be required.

According to one or more embodiments, the gas distribution apparatus can be used to subject a substrate to processing prior to and/or after forming the layer. This processing can be performed in the same chamber or in one or more separate processing chambers. In some embodiments, the substrate is moved from the first chamber to a separate, second chamber for further processing. The substrate can be moved directly from the first chamber to the separate processing chamber, or it can be moved from the first chamber to one or more transfer chambers, and then moved to the desired separate processing chamber. Accordingly, the processing apparatus may comprise multiple chambers in communication with a transfer station. An apparatus of this sort may be referred to as a “cluster tool” or “clustered system”, and the like.

Generally, a cluster tool is a modular system comprising multiple chambers which perform various functions including substrate center-finding and orientation, degassing, annealing, deposition and/or etching. According to one or more embodiments, a cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber may house a robot that can shuttle substrates between and among processing chambers and load lock chambers. The transfer chamber is typically maintained at a vacuum condition and provides an intermediate stage for shuttling substrates from one chamber to another and/or to a load lock chamber positioned at a front end of the cluster tool. Two well-known cluster tools which may be adapted for the present invention are the Centura® and the Endura®, both available from Applied Materials, Inc., of Santa Clara, Calif. The details of one such staged-vacuum substrate processing apparatus is disclosed in U.S. Pat. No. 5,186,718, entitled “Staged-Vacuum Wafer Processing Apparatus and Method,” Tepman et al., issued on Feb. 16, 1993. However, the exact arrangement and combination of chambers may be altered for purposes of performing specific steps of a process as described herein. Other processing chambers which may be used include, but are not limited to, cyclical layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etch, pre-clean, chemical clean, thermal treatment such as RTP, plasma nitridation, degas, orientation, hydroxylation and other substrate processes. By carrying out processes in a chamber on a cluster tool, surface contamination of the substrate with atmospheric impurities can be avoided without oxidation prior to depositing a subsequent film.

According to one or more embodiments, the substrate is continuously under vacuum or “load lock” conditions, and is not exposed to ambient air when being moved from one chamber to the next. The transfer chambers are thus under vacuum and are “pumped down” under vacuum pressure. Inert gases may be present in the processing chambers or the transfer chambers. In some embodiments, an inert gas is used as a purge gas to remove some or all of the reactants after forming the silicon layer on the surface of the substrate. According to one or more embodiments, a purge gas is injected at the exit of the deposition chamber to prevent reactants from moving from the deposition chamber to the transfer chamber and/or additional processing chamber. Thus, the flow of inert gas forms a curtain at the exit of the chamber.

A substrate can be processed in single substrate deposition chambers using, for example, the gas distribution apparatus described. In such chambers, a single substrate is loaded, processed and unloaded before another substrate is processed. A substrate can also be processed in a continuous manner, like a conveyer system, in which multiple substrate are individually loaded into a first part of the chamber, move through the chamber and are unloaded from a second part of the chamber. The shape of the chamber and associated conveyer system can form a straight path or curved path. Additionally, the processing chamber may be a carousel in which multiple substrates are moved about a central axis and are exposed to deposition, etch, annealing, cleaning, etc. processes throughout the carousel path.

During processing, the substrate can be heated or cooled. Such heating or cooling can be accomplished by any suitable means including, but not limited to, changing the temperature of the substrate support and flowing heated or cooled gases to the substrate surface. In some embodiments, the substrate support includes a heater/cooler which can be controlled to change the substrate temperature conductively. In one or more embodiments, the gases (either reactive gases or inert gases) being employed are heated or cooled to locally change the substrate temperature. In some embodiments, a heater/cooler is positioned within the chamber adjacent the substrate surface to convectively change the substrate temperature.

The substrate can also be stationary or rotated during processing. A rotating substrate can be rotated continuously or in discreet steps. For example, a substrate may be rotated throughout the entire process, or the substrate can be rotated by a small amount between exposure to different reactive or purge gases. Rotating the substrate during processing (either continuously or in steps) may help produce a more uniform deposition or etch by minimizing the effect of, for example, local variability in gas flow geometries.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.