Disclosure of Invention
In view of this, the embodiments of the present disclosure provide a wafer plasma etching apparatus, by providing a plurality of gas feed holes at the peripheral edge of the heat stage, the pipe assembly introduces gas into the gas feed holes, the gas is blown to the wafer through the gas feed holes, so that the gas flow field above the wafer can be changed, the gas speed or the gas amount blown to the wafer by the gas feed holes can be adjusted by the adjusting mechanism, and the influence range of the gas can be controlled, thereby realizing adjustment of the gas flow field above the wafer, and ensuring the uniformity of wafer etching.
The embodiment of the specification provides the following technical scheme that the wafer plasma etching equipment comprises:
The wafer is placed on the heat table, and a plurality of gas feed holes are formed in the circumferential edge of the heat table;
The pipeline assembly is used for introducing gas into the plurality of gas feed holes;
And the adjusting mechanism can adjust the speed and/or the amount of the gas blown to the wafer by the gas feed holes so as to change the flow field above the wafer.
Preferably, the adjusting mechanism comprises a cover plate and an elevating mechanism, the cover plate comprises an elevating part and an adjusting part, the elevating part and the adjusting part are integrally formed, the adjusting part at least partially extends to the upper part of the gas feed hole, the elevating part is connected with the elevating mechanism, and the elevating mechanism drives the elevating part to move so that the adjusting part moves towards the direction close to or far away from the gas feed hole.
Preferably, a gas feeding section is formed between the adjusting part and the circumferential edge of the heat table, and the size of the gas feeding section is changed when the adjusting part moves towards the direction approaching to or away from the gas feeding hole.
Preferably, the lifting part is arranged around the heat table, and the inner wall of the lifting part is at least partially attached to the outer wall of the heat table.
Preferably, the lifting mechanism comprises one of an electric cylinder, an air cylinder, a ball screw and an electromagnetic integrated guide rail.
Preferably, the top of the heat table is provided with a containing groove, the containing groove is used for containing the wafer, a transition surface is formed between the containing groove and the edge of the heat table, and the transition surface is an inclined surface.
Preferably, the transition surface is provided with a plurality of special-shaped through holes, and the special-shaped through holes are respectively communicated with the gas feed-in holes.
Preferably, the pipeline assembly comprises a main pipeline and a plurality of branch pipelines, wherein a first end of the main pipeline penetrates through the heat table to be communicated with an external air supply system, a second end of the main pipeline is communicated with a plurality of branch pipelines, and a plurality of branch pipelines are respectively communicated with a plurality of air feed-in holes.
Preferably, the external air supply system comprises two supply modes of constant air inlet pressure or constant air outlet flow.
Preferably, a plurality of the gas feed holes are provided, and the plurality of the gas feed holes are uniformly distributed on the heat stage.
Compared with the prior art, the beneficial effects that above-mentioned at least one technical scheme that this description embodiment adopted can reach include at least:
Through seting up a plurality of gas feed holes in the peripheral edge department of hot bench, the pipeline subassembly lets in gas to gas feed hole in, gas blows to wafer department via gas feed hole, can change the gas flow field above the wafer, adjusts gas feed hole to the gas speed or the gas volume of wafer through adjustment mechanism, can control gaseous influence scope to the realization is adjusted the gas flow field above the wafer, guarantees the homogeneity of wafer etching.
Detailed Description
Embodiments of the present application will be described in detail below with reference to the accompanying drawings.
Other advantages and effects of the present application will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present application with reference to specific examples. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. The application may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
It is noted that various aspects of the embodiments are described below within the scope of the following claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the present disclosure, one skilled in the art will appreciate that one aspect described herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, apparatus may be implemented and/or methods practiced using any number and aspects set forth herein. In addition, such apparatus may be implemented and/or such methods practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.
It should also be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present application by way of illustration, and only the components related to the present application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.
In addition, in the following description, specific details are provided in order to provide a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects may be practiced without these specific details.
The plasma etching process is a common process in semiconductor processing, the WAFER is often required to be controlled in the etching process, and the common temperature control method mainly comprises the following two steps:
1. The electrostatic chuck is conducted with helium gas for heat conduction, and the hot plate is directly heated.
2. The hot plate (with higher temperature and lower cost) is heated by temperature control.
However, the conventional common hot plate has only a heating function, and although the heating is relatively uniform, when the gas flow field in the facing cavity is uneven, an effective adjusting means is lacked, so that gas molecules, effective etching particles, ions and the like are unevenly distributed at the position close to the center and the position close to the edge in the processing of the wafer, and the etching rate and the etching morphology are different.
The following describes the technical scheme provided by each embodiment of the present application with reference to the accompanying drawings.
As shown in fig. 2 to 5, a wafer plasma etching apparatus includes:
the wafer 6 is placed on the heat table 1, and a plurality of gas feed holes 3 are formed in the circumferential edge of the heat table 1;
a pipe assembly for introducing gas into the plurality of gas feed holes 3;
and the adjusting mechanism can adjust the speed and/or the amount of the gas blown to the wafer 6 by the gas feed holes 3 so as to change the flow field above the wafer 6.
By arranging a plurality of gas feed holes 3 at the circumferential edge of the heat table 1, the pipeline assembly is used for introducing gas into the gas feed holes 3, the gas is blown to the position of the wafer 6 through the gas feed holes 3, the gas flow field above the wafer 6 can be changed, the gas speed or the gas quantity blown to the wafer 6 by the gas feed holes 3 can be regulated through the regulating mechanism, the influence range of the gas can be controlled, and thus the regulation of the gas flow field above the wafer 6 is realized, and the uniformity of etching of the wafer 6 is ensured.
It should be noted that, the gas introduced into the gas feed hole 3 through the pipe assembly may be a process gas, a dilution gas, or a mixed gas, so as to adjust the concentration of the reactive ions in the outer region of the wafer 6 or adjust the thickness of the protective layer on the etching sidewall. The etching effect on the wafer 6 can be adjusted by changing the kind of the gas, the speed of the gas blown to the wafer 6 by the gas feed hole 3, or the amount of the gas.
The gas is blown to the wafer 6 through the gas feed hole 3, which affects the outer region of the wafer 6 to form an affected area, and the size of the affected area is affected by the gas outlet speed and the gas amount, and the size of the affected area can be adjusted by the gas outlet speed or the gas amount.
The flow field shown in fig. 1 is a schematic flow field in the prior art, which can cause uneven distribution of gas molecules, effective etching particles, ions and the like near the center position and near the edge position in the processing of the wafer 6, so that different etching rates and etching morphologies are caused. As shown in fig. 4, in the flow field schematic diagram of the present application, due to the existence of the gas feeding hole 3, gas can be blown into the edge region of the wafer 6, so that the distribution of gas molecules, effective etching particles, ions and the like can be ensured to be uniform, and the uniformity of etching rate can be realized.
As shown in fig. 2-4, in some embodiments, the adjusting mechanism includes a cover plate 2 and an elevating mechanism 9, the cover plate 2 includes an elevating portion 22 and an adjusting portion 21, the elevating portion 22 and the adjusting portion 21 are integrally formed, the adjusting portion 21 extends at least partially above the gas feeding hole 3, the elevating portion 22 is connected with the elevating mechanism 9, the elevating mechanism 9 drives the elevating portion 22 to move, so that the adjusting portion 21 moves towards a direction approaching or separating from the gas feeding hole 3, the cover plate 2 is driven by the elevating mechanism 9 to move, so that the cover plate 2 moves along an axial direction of the heat table 1, the adjusting portion 21 of the cover plate 2 extends at least partially above the gas feeding hole 3, when the elevating mechanism 9 drives the adjusting portion 21 to move by the elevating portion 22, the adjusting portion 21 moves towards a direction approaching or separating from a top of the heat table 1, so that a distance between the adjusting portion 21 and the gas feeding hole 3 changes.
The cross section of the cover plate 2 is 7-shaped, the adjusting portion 21 is provided horizontally, and the lifting portion 22 is provided vertically.
As shown in fig. 2 and fig. 4, in some embodiments, a gas feeding section is formed between the adjusting portion 21 and the circumferential edge of the heat table 1, when the adjusting portion 21 moves towards the direction close to or away from the gas feeding hole 3, the size of the gas feeding section changes, the adjusting portion 21 extends above the gas feeding hole 3, a gas feeding section is formed between the adjusting portion 21 and the circumferential edge of the top of the heat table 1, when the lifting mechanism 9 drives the adjusting portion 21 to move towards the direction close to or away from the gas feeding hole 3, the distance between the adjusting portion 21 and the top of the heat table 1 changes, so that the size of the gas feeding section changes, and by changing the size of the gas feeding section, the change of the gas speed or the gas amount can be realized, thereby changing the etching rate of the outer region of the wafer 6.
As shown in fig. 2 and 4, in some embodiments, the lifting portion 22 is disposed around the heat stage 1, at least a part of the inner wall of the lifting portion 22 is attached to the outer wall of the heat stage 1, and the inner wall of the lifting portion 22 is attached to the outer wall of the heat stage 1, so that the gas blown out from the gas feed hole 3 can be prevented from being emitted to the outer side of the heat stage 1, and the gas can be ensured to be vertically located at the wafer 6.
In the present embodiment, the elevating portion 22 is in sliding sealing contact with the heat stage 1. In other embodiments, other arrangements may be adopted, and it is only necessary to ensure that the lifting portion 22 and the heat stage 1 can be sealed, and that the lifting portion 22 can move in the vertical direction with respect to the heat stage 1.
In some embodiments, as shown in fig. 4, the lifting mechanism 9 comprises one of an electric cylinder, an air cylinder, a ball screw, and an electromagnetic integrated guide rail. In the present embodiment, the lifting mechanism 9 is an electric cylinder, and the telescopic end of the electric cylinder is connected to the lifting portion 22. In other embodiments, the lifting mechanism 9 may be one of an air cylinder, a ball screw, and an electromagnetic integrated guide rail, so long as the lifting mechanism 9 can drive the lifting portion 22 to perform lifting motion.
As shown in fig. 2-4, in some embodiments, a receiving groove is formed at the top of the heat table 1, the receiving groove is used for placing the wafer 6, a transition surface 4 is formed between the receiving groove and the edge of the heat table 1, the transition surface 4 is an inclined surface, the receiving groove is formed at the top of the heat table 1, and the inclined transition surface 4 is formed at the edge of the receiving groove and the edge of the heat table 1, and the center of the receiving groove is located on the axis of the heat table 1, so that the wafer 6 is located at the center of the top of the heat table 1 when falling.
As shown in fig. 2 to fig. 4, in some embodiments, the transition surface 4 is provided with a plurality of special-shaped through holes 5, the plurality of special-shaped through holes 5 are respectively communicated with the plurality of gas feed holes 3, and by providing the special-shaped through holes 5 which are communicated with the gas feed holes 3 on the transition surface 4, part of the gas in the gas feed holes 3 can vertically pass through the special-shaped through holes 5 to the wafer 6, and the special-shaped through holes 5 are positioned above the accommodating groove, so that the height of the gas outlet can be raised, thereby facilitating the gas to be fed into the wafer 6 further.
As shown in fig. 4, in some embodiments, the pipe assembly includes a main pipe 7 and a plurality of branch pipes 8, a first end of the main pipe 7 passes through the heat table 1 and is communicated with an external gas supply system, a second end of the main pipe 7 is communicated with a plurality of branch pipes 8, a plurality of branch pipes 8 are respectively communicated with a plurality of gas feed holes 3, the main pipe 7 extends to the outside of the heat table 1 and is communicated with the external gas supply system, the external gas supply system supplies gas into the main pipe 7, gas in the main pipe 7 flows into a plurality of branch pipes 8 respectively, and gas in a plurality of branch pipes 8 flows into corresponding gas feed holes 3 respectively and then flows out to the wafer 6 through the top of the gas feed holes 3.
In some embodiments, the external air supply system comprises two supply modes of constant inlet air pressure or constant outlet air flow. The air supply mode is divided into two air inlet modes of a front end UPC or an MFC, the air supply mode is adjusted by adjusting the size of an opening (namely, the distance between the adjusting part 21 and the heat table 1), and the two modes have different adjusting functions:
UPC, controlling the inlet pressure to be constant, reducing the air resistance when the opening is increased, and increasing the outlet speed and the gas quantity.
MFC, controlling the constant flow of the gas outlet, increasing the opening, i.e. increasing the outlet area, and at the same time, the constant flow of the gas outlet, and reducing the speed of the gas passing through the unit area.
As shown in fig. 2-3, in some embodiments, the plurality of gas feed holes 3 are provided, the plurality of gas feed holes 3 are uniformly distributed on the heat table 1, and by providing the plurality of gas feed holes 3 and uniformly distributing the plurality of gas feed holes 3 in a circular shape at the edge of the heat table 1, it is ensured that the gas sweeps uniformly on the heat table 1, so that the impact area of the gas on the wafer 6 is a continuous uniform ring shape, as shown in fig. 5, and the inner shadow area in fig. 5 is the impact area of the gas on the wafer 6.
The same and similar parts of the embodiments in this specification are all mutually referred to, and each embodiment focuses on the differences from the other embodiments. In particular, for the method embodiments described later, since they correspond to the system, the description is relatively simple, and reference should be made to the description of some of the system embodiments.
The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present application should be included in the present application. Therefore, the protection scope of the application is subject to the protection scope of the claims.