Summary of the invention
For the problems referred to above in background technology, the present invention proposes a kind of clean method of plasma process chamber.
First aspect present invention provides a kind of clean method for plasma process chamber, wherein, clean air is passed into chamber interior by the gas spray of plasma process chamber, then apply radio-frequency (RF) energy clean air is excited into plasma cleans chamber interior, wherein, in the refrigerating gas supply line of described plasma process chamber, supply refrigerating gas is continued.
Further, described clean method comprises the steps: that in the refrigerating gas supply line of described plasma process chamber, continue supply refrigerating gas terminates to clean.
Further, described refrigerating gas supply line is arranged among base station, and gas supply pipe has a puff prot, and described puff prot is blown facing to substrate back.
Further, a refrigerating gas feeding mechanism is connected with below described refrigerating gas supply line.
Further, the below of described refrigerating gas feeding mechanism is also connected with a control device.
Further, the refrigerating gas supply line of described refrigerating gas feeding mechanism upstream is also connected with a valve.
Further, the pressure of described supply refrigerating gas is be greater than chamber interior pressure when described plasma process chamber performs clean.
Further, the span of the pressure of described supply refrigerating gas is 10mT ~ 10T.
Further, described clean air is oxygen.
Further, described refrigerating gas is helium.
The clean method of plasma process chamber provided by the invention, can ensure that helium supply line can not be polluted in clean process, can not because of cleaning course in inner-walls of duct contaminant deposition, even blocked.
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described.
It is to be noted; " semiconductor arts piece ", " wafer " and " substrate " these words often will be exchanged use in explanation subsequently; in the present invention; they all refer to that, in the processed process conditions of process chamber, process conditions is not limited to wafer, substrate, substrate, large-area flat-plate substrate etc.For convenience of description, mainly exemplary illustration will be made for " substrate " herein in execution mode illustrates and illustrates.
Hereafter be described for plasma etch chamber room, it will be appreciated by those skilled in the art that and the present invention is not limited thereto, the present invention is widely applicable for various plasma process chamber, such as chemical vapor deposition chamber (CVD) etc.
Fig. 1 shows the structural representation of plasma process chamber, and especially, plasma process chamber is plasma etch chamber room 100.Plasma etch chamber room 100 has a process chambers (not shown), and process chambers is essentially cylindricality, and process chambers sidewall 102 perpendicular, there is in process chambers top electrode arranged in parallel and bottom electrode.Usually, the region between top electrode and bottom electrode is processing region P, this region P by formation high-frequency energy to light and maintain plasma.Above base station 106, place substrate W to be processed, this substrate W can be the semiconductor chip treating to etch or to process or the glass plate treating to be processed into flat-panel monitor.Wherein, described base station 106 is for clamping substrate W.Reacting gas is input to the gas spray 109 in process chambers from gas source 103, one or more radio-frequency power supply 104 can be applied individually on the bottom electrode or is applied on top electrode and bottom electrode respectively simultaneously, in order to be transported on bottom electrode by radio-frequency power or on top electrode and bottom electrode, thus produce large electric field in process chambers inside.In the involved processing region P between the upper and lower electrodes of most of electric field line, this electric field accelerates the electronics being present in process chambers inside on a small quantity, makes it the gas molecule collision with the reacting gas inputted.These collisions cause exciting of the ionization of reacting gas and plasma, thus produce plasma in process chambers.The neutral gas molecule of reacting gas loses electronics when standing these highfields, leaves the ion of positively charged.The ion of positively charged accelerates towards bottom electrode direction, and the neutral substance in processed substrate is combined, and excites substrate to process, i.e. etching, deposit etc.Certain suitable position of plasma etch chamber room 100 is provided with exhaust gas region, and exhaust gas region is connected with external exhaust apparatus (such as vacuum pump 105), in order to extract chamber out by by the reacting gas crossed and bi-product gas in processing procedure.Wherein, plasma confinement ring 107 for by plasma confinement in processing region P.Chamber sidewall 102 is connected with earth terminal, is wherein provided with a resistance 108.
As shown in Figure 1, plasma etch chamber room 100 also comprises refrigerating gas supply line 101, and described refrigerating gas supply line 101 is arranged among base station 106 vertically.Wherein, the length of described refrigerating gas supply line 101 is enough lain across whole base station 106, and refrigerating gas supply line 101 has a puff prot, and therefore, described puff prot can facing to its upper substrate W back side air blowing of placing.A refrigerating gas feeding mechanism 110 is also connected with, for supplying refrigerating gas to refrigerating gas supply line 101 below refrigerating gas supply line 101.Be connected with a control device 111 below refrigerating gas feeding mechanism 110, supply refrigerating gas for controlled cooling model gas supply device 110 to refrigerating gas supply line 101.
Fig. 2 is the structural representation of the refrigerating gas supply system of the plasma process chamber of prior art.As shown in Figure 2, in the base station 106 that substrate W is placed into plasma etch chamber room 100 carries out processing procedure, substrate W is clamped on base station 106, and refrigerating gas is jet by the refrigerating gas supply line 101 alignment substrate W back side, adjusts the temperature of substrate W.After the substrate W of the 100 pairs of specific quantities in plasma etch chamber room carries out processing procedure, a cleaning step can be performed to chamber.But, according to the mechanism of prior art, the polymer pollution of chamber can little by little fall into refrigerating gas supply line 101, add refrigerating gas supply line 101 can be bled and inflate always, after a period of time, whole refrigerating gas supply line 101 all can be contaminated, becomes the source of particle contamination.As shown in Figure 2; gas supply device 110 upstream of prior art on cooling air pipe 101 can arrange a protective device 112; the device that protective device 112 pours in down a chimney for preventing polymer from polluting or pollutes as collected polymer; then periodic cleaning even changes refrigerating gas; which increase the cost of plasma etch chamber room 100; and extend the downtime of plasma etch chamber room 100, reduce the utilization rate of plasma etch chamber room 100.Wherein, whether the first valve a1 is used for connection between controlled cooling model gas supply device 110 and refrigerating gas supply line 101, and whether the second valve b1 is used for the connection of control protective unit 112.
Fig. 3 is the structural representation of the refrigerating gas supply system of plasma process chamber according to the present invention's specific embodiment.According to analysis, in the processing procedure process of substrate W, base station 106 is clamped with substrate W, and supplies refrigerating gas among refrigerating gas supply line 101 always, now polymer pollutes and can not fall into refrigerating gas supply line 101 li.Therefore, judge that polymer pollutes only just likely to fall in refrigerating gas supply line 101 when performing clean processing procedure to chamber.In fact, when performing clean processing procedure to chamber, refrigerating gas supply line 101 does not flow refrigerating gas.Judgement above having had, in refrigerating gas supply line 101, a certain amount of refrigerating gas is being flowed when performing clean processing procedure to chamber, pressure in refrigerating gas supply line 101 is less times greater than the pressure of chamber interior, just can prevent polymer from polluting completely falls in refrigerating gas supply line 101, the contaminated problem of final thoroughly solution refrigerating gas supply line 101.
First aspect present invention provides a kind of clean method for plasma process chamber, wherein, pass into clean air by the gas spray of plasma process chamber to chamber interior, then apply radio-frequency (RF) energy and clean air is excited into plasma chamber interior is cleaned.Wherein, in the refrigerating gas supply line 201 of described plasma process chamber, supply refrigerating gas is continued.In accordance with a preferred embodiment of the present invention, described clean method comprises the steps: that in the refrigerating gas supply line 201 of described plasma process chamber, continue supply refrigerating gas terminates to clean.
Further, described refrigerating gas supply line 201 is arranged among base station 206, and refrigerating gas supply line 201 has a puff prot, and described puff prot is blown facing to the substrate W back side.
Further, below described refrigerating gas supply line 201, be connected with a refrigerating gas feeding mechanism 210, for supplying refrigerating gas to refrigerating gas supply line 201.
Further, the below of described refrigerating gas feeding mechanism 210 is also connected with a control device 211, and it supplies refrigerating gas for controlled cooling model gas supply device 210 toward refrigerating gas supply line 201.Wherein, a valve a2 is also provided with among the refrigerating gas supply line 201 refrigerating gas feeding mechanism 210 had.
Further, the pressure of described supply refrigerating gas is be greater than chamber interior pressure when described plasma process chamber performs clean.
Further, the span of the pressure of described supply refrigerating gas is 10mT ~ 10T.Exemplarily, the span of the pressure of described supply refrigerating gas comprises 20mT, 80mT, 2T, 5T, 5.6T, 8T etc.
Further, described clean air is oxygen.
Further, described refrigerating gas is helium.
The clean method of plasma process chamber provided by the invention, can ensure that helium supply line can not be polluted in clean process, can not because of cleaning course in inner-walls of duct contaminant deposition, even blocked.And; without the need to arranging any protective device; the device pouring in down a chimney or pollute as collected polymer is polluted for preventing polymer; then periodic cleaning even changes refrigerating gas; it reduce the cost of plasma etch chamber room; and extend the downtime of plasma etch chamber room, reduce the utilization rate of plasma etch chamber room.
Although content of the present invention has done detailed introduction by above preferred embodiment, will be appreciated that above-mentioned description should not be considered to limitation of the present invention.After those skilled in the art have read foregoing, for multiple amendment of the present invention and substitute will be all apparent.Therefore, protection scope of the present invention should be limited to the appended claims.In addition, any Reference numeral in claim should be considered as the claim involved by restriction; " comprise " word and do not get rid of device unlisted in other claim or specification or step; The word such as " first ", " second " is only used for representing title, and does not represent any specific order.