JP2012227209A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a substrate processing apparatus which reduces a burden for introducing new equipment to an existing substrate processing apparatus and removes a thick deposition film adhered to an inner wall of the substrate processing apparatus.SOLUTION: A substrate processing apparatus 1 includes: a chamber 11; a stage 12 holding a substrate in the chamber 11; a cleaning gas supply system 60 supplying a cleaning gas, removing a deposit adhered to the interior of the chamber 11 through a process performed to the substrate, to the chamber 11; and an exhaust system 30 exhausting the gas in the chamber 11 from a gas exhaust port 15 provided at a bottom wall of the chamber 11. In the substrate processing apparatus 1, a groove 16 is provided around the gas exhaust port 15 in the chamber 11.

Description

  The present invention relates to a substrate processing apparatus.

  In the manufacturing process of a semiconductor device, a film formation process, a modification process, an oxidation diffusion process, and an etching process are performed on a substrate to be processed, thereby manufacturing the semiconductor device. Among these, the CVD (Chemical Vapor Deposition) method is frequently used for the film forming process. In the film forming process, since the material to be formed is deposited on the inner wall of the film forming chamber, cleaning is performed by periodically flowing a radical gas to react with the deposited film on the inner wall, thereby removing the deposited film. However, when the deposited film is removed in the CVD apparatus, Si-based powder is generated, and periodic cleaning is performed to cause clogging in the exhaust system of the CVD apparatus.

  Therefore, conventionally, in the exhaust system of the film forming apparatus for forming the Si-based film, a storage unit for dropping and storing the Si-based powder deposited in the pipe is provided, and the Si-based powder in the storage unit is taken out to the outside. A structure having a flange that can be freely opened and closed has been proposed (see, for example, Patent Document 1).

JP 2001-73143 A

  However, as in the technique described in Patent Document 1, it is necessary to introduce a new mechanism to the existing film forming apparatus by providing a housing part and a flange in the exhaust system of the film forming apparatus, and in some cases activated. There was a problem that a facility for removing Si-based powder was required. In addition, compared to conventional LSI (Large Scale Integrated Circuit) manufacturing processes, thin films used in various electronic devices such as amorphous silicon solar cells, thin film transistors, photosensors, and semiconductor protective films have become larger in area. In general, a plasma CVD apparatus is used for manufacturing such a large-area thin film. As a large-area thin film is manufactured, a thick deposited film adheres to the inner wall of the plasma CVD apparatus, but if this thick deposited film is removed with a cleaning gas, a large amount of Si-based powder is generated, so that equipment with higher processing capacity is available. Is required.

  The present invention has been made in view of the above, and can reduce the burden of introducing new equipment on an existing substrate processing apparatus and can remove a thick deposited film attached to the inner wall of the substrate processing apparatus. The object is to obtain a device.

  In order to achieve the above object, a substrate processing apparatus according to the present invention includes a chamber, substrate holding means for holding the substrate in the chamber, and a cleaning gas for removing deposits attached to the chamber by processing the substrate. A substrate processing apparatus comprising: a cleaning gas supply unit that supplies a gas into the chamber; and a discharge unit that discharges the gas in the chamber from a gas discharge port provided in a bottom wall of the chamber. A groove is provided around the gas discharge port.

  According to the present invention, since the groove serving as a trap for the deposit powder adhering to the inner wall of the chamber is provided around the exhaust port at the bottom of the chamber, the deposit powder inside the groove reacts with the cleaning gas to efficiently vaporize the deposit powder. Can be removed. In addition, by vaporizing the deposit powder, it can be processed by the existing combustion exclusion device, and the cleaning gas for initializing the film forming chamber can be used when vaporizing the deposit powder trapped in the groove, This has the effect of reducing the introduction load on existing equipment.

FIG. 1 is a cross-sectional view schematically showing an example of the configuration of the substrate processing apparatus according to the first embodiment. FIG. 2 is a diagram schematically showing the structure of the groove around the gas exhaust port according to the second embodiment.

  A substrate processing apparatus according to an embodiment of the present invention will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view schematically showing an example of the configuration of the substrate processing apparatus according to the first embodiment. Here, a plasma CVD apparatus is taken as an example of the substrate processing apparatus. The substrate processing apparatus 1 can be broadly divided into a film formation processing unit 10, an exhaust system 30, and a gas supply system 40.

  The film formation processing unit 10 has a chamber 11 made of, for example, aluminum or aluminum alloy. The chamber 11 has, for example, a cylindrical shape. Inside the chamber 11, a stage 12, which is a substrate holding unit that horizontally supports a substrate to be processed, is disposed. The stage 12 is disposed in the vicinity of the central portion in the horizontal direction in the chamber 11 and is supported by a support member (not shown) inside the chamber 11. The stage 12 incorporates a substrate heating means such as a heater and a holding mechanism for holding the substrate by a method such as vacuum suction. The heater is used when heating the substrate to a predetermined temperature when processing the substrate. Further, a substrate loading / unloading port (not shown) is provided on the side wall of the chamber 11 and can be opened and closed by a gate valve (not shown).

  A shower head 13, which is a gas discharge member, is provided above the stage 12 so as to face the substrate holding surface of the stage 12 in the chamber 11. The shower head 13 also functions as an upper electrode and is supported on the side wall of the chamber 11 via an insulating member 14. The shower head 13 is provided with a large number of discharge holes 13 </ b> A, and gas supplied from the upper part of the chamber 11 is supplied to the space in the chamber 11 in a shower shape. Although not shown, the shower head 13 is connected to a high frequency power supply unit for supplying high frequency power to the shower head 13 via a power supply line. Thus, the stage 12 and the shower head 13 constitute a pair of parallel plate electrodes.

  A gas exhaust port 15 is provided near the center of the bottom of the chamber 11. The gas exhaust port 15 has, for example, a circular opening. Further, around the gas exhaust port 15, a groove 16 for trapping deposit powder generated by cleaning after the substrate processing and the vaporization reaction of the deposit powder trapped mainly in the groove 16 by the cleaning gas are promoted. And a heating unit 17.

  Further, around the gas exhaust port 15 at the bottom of the chamber 11, there is a mortar-shaped slope-constituting member 18 that slopes toward the groove 16 from a predetermined height with respect to the position of the groove 16 on the side wall of the chamber 11. Is provided. The slope constituting member 18 is provided so that the deposit powder removed at the time of cleaning and falling to the lower side of the chamber 11 further reaches the groove 16 by its own weight.

  The inclined surface 18A of the inclined surface constituting member 18 can be made of, for example, aluminum or aluminum alloy having good thermal conductivity. By using the inclined surface 18A made of aluminum or aluminum alloy having good thermal conductivity, the deposit powder can be efficiently vaporized by the cleaning gas while heating the slope constituting member 18.

  In addition, a vibration portion (not shown) that vibrates the inclined surface 18A may be provided on the inclined surface 18A of the inclined member 18. By giving vibration to the inclined surface 18 </ b> A by the vibrating portion, the deposit powder remaining on the inclined surface 18 </ b> A can be moved toward the groove 16. An ultrasonic generator that transmits an ultrasonic wave to the inclined surface 18A by applying an AC voltage to the piezoelectric element can be used as the vibration unit. In addition, a blocking member 19 is provided between the gas exhaust port 15 and the groove 16 to prevent the deposit powder sliding down on the slope constituting member 18 from directly entering the gas exhaust port 15. The blocking member 19 has a configuration in which members constituting the gas exhaust port 15 are extended into the chamber 11 so that the end of the gas exhaust port 15 is located above the bottom surface of the chamber 11. Here, the case where the slope constituting member 18 is provided at the bottom of the chamber 11 is shown, but the present invention is not limited to this. For example, the chamber 11 has a convex shape toward the gas exhaust port 15 at the bottom. A structure with a simple structure, that is, a mortar-shaped surface inclined so that the surface constituting the bottom portion becomes lower toward the gas exhaust port 15 from the boundary with the side wall may be used.

  An exhaust system 30 is provided at the gas exhaust port 15 at the bottom of the chamber 11. The exhaust system 30 includes a pipe 31 connected to the gas exhaust port 15 at the bottom of the chamber 11, a vacuum pump 32 that is an exhaust means connected to the pipe 31, and the degree of exhaust of gas in the chamber 11 by the vacuum pump 32. And a switching valve 33.

  In the vicinity of the upper portion of the chamber 11, gas supply ports 20 and 21 are provided. In this figure, a gas supply port 20 for supplying a processing gas is provided near the center of the upper surface of the chamber 11, and a gas supply port 21 for supplying a cleaning gas is provided on the side wall of the chamber 11.

The gas supply system 40 includes a processing gas supply system 50 that supplies a processing gas, and a cleaning gas supply system 60 that supplies a cleaning gas. The processing gas supply system 50 includes a pipe 51 connected to the gas supply port 20 provided in the upper part of the chamber 11, a gas supply source 52 provided at the other end of the pipe 51, and the gas supply source 52 to the chamber 11. And a gas valve 53 provided on a pipe 51 for switching on / off the supply of the processing gas to the inside. When forming a Si film as a gas used for the gas supply source 52, for example, SiH ₃ gas, H ₂ gas, Ar gas, or the like can be used. In the drawing, only one pipe 51, gas supply source 52, and gas valve 53 are shown, but a gas valve 53 and a pipe 51 are provided for each gas supply source 52.

The cleaning gas supply system 60 includes a pipe 61 connected to the gas supply port 21 provided on the side wall of the chamber 11, a gas supply source 62 provided at the other end of the pipe 61, and the gas supply source 62 to the chamber 11. A gas valve 63 provided on a pipe 61 for switching on / off the supply of the cleaning gas to the inside. As the cleaning gas, when cleaning the Si-based film, a gas containing fluorine such as F ₂ , NF ₃ , ClF ₃ , CF ₄ or a mixed gas containing one or more of these, and N ₂ , Ar, He are used. , Kr, Xe, Ne, or other inert gas or a mixed gas containing one or more of them can be used. After supplying these cleaning gases, plasma is generated in the space between the shower head 13 and the stage 12 by applying high-frequency power to the electrodes provided above and below the chamber 11 from the high-frequency power supply unit. As the gas supply source 62, a gas supply source corresponding to the gas used is provided. In the drawing, only one pipe 61, gas supply source 62, and gas valve 63 are shown, but each gas supply source 62 is provided with a gas valve 63 and a pipe 61. Further, as the cleaning gas, these cleaning gases by remote plasma may be supplied as radicals.

  Next, an outline of processing in the substrate processing apparatus 1 having such a configuration will be described by taking as an example the case of forming a Si film. First, a substrate is loaded into the chamber 11 from a substrate loading / unloading port (not shown), placed on the stage 12, and fixed by a holding mechanism such as a vacuum chuck mechanism. Next, the gas in the chamber 11 is exhausted by the exhaust system 30, and the inside of the chamber 11 is set to a predetermined degree of vacuum. Further, the stage 12 is heated to a temperature required for film formation.

Thereafter, a processing gas (for example, SiH ₃ gas, H ₂ gas, Ar gas, etc.) used when forming a Si film, for example, is supplied from the processing gas supply system 50 into the chamber 11 through the gas supply port 20. The liquid is supplied to the space between the shower head 13 and the stage 12 through the discharge hole 13 </ b> A of the shower head 13. When the pressure in the chamber 11 reaches a predetermined pressure, high frequency power is applied from the high frequency power supply unit to the shower head 13 that is the upper electrode while the stage 12 that is the lower electrode is grounded. Plasma is generated in a space between the two. As a result, the processing gas supplied from the processing gas supply system 50 is activated, and a desired film (here, Si film) is formed on the substrate. At this time, a film is also deposited on the constituent members in the chamber 11 in contact with the plasma in the same manner as on the substrate.

  When a film (Si film) having a predetermined thickness is formed on the substrate, the supply of high-frequency power from the high-frequency power supply unit is stopped, the chamber 11 is sufficiently evacuated, the valve 33 is closed, and the chamber 11 Nitrogen gas, inert gas, or the like is supplied into the chamber to obtain a predetermined pressure, and the substrate on the stage 12 is unloaded from the chamber 11 through the substrate loading / unloading port. The outline of the film forming process in the substrate processing apparatus 1 has been described above.

  Next, an outline of the cleaning process in the substrate processing apparatus 1 will be described. When the film forming process is completed and the substrate is unloaded from the loading / unloading port of the chamber 11, the loading / unloading port is closed, and the exhaust system 30 evacuates the chamber 11 to a predetermined degree of vacuum.

  Next, the cleaning gas and its radical are supplied from the cleaning gas supply system 60 into the chamber 11. At this time, the film forming material on the inner wall of the chamber 11 generated by the film forming process is vaporized in the form of silicon fluoride by a cleaning gas such as fluorine or radicals thereof, but a part of the film forming material is not yet deposited powder. The reaction falls to the slope constituting member 18 below the chamber 11 while being reacted. The fallen sediment powder slides down by its own weight on the inclined surface 18A constituting the slope constituting member 18 provided at the bottom of the chamber 11 and into the groove 16 formed around the gas exhaust port 15 near the center of the bottom of the chamber 11. Be guided. At this time, the blocking member 19 around the gas exhaust port 15 can prevent the fallen sediment powder from directly entering the gas exhaust port 15. Moreover, in order to prevent the unreacted deposit powder falling on the inclined surface 18A of the inclined member 18 from staying on the inclined surface 18A, the inclined surface 18A may be vibrated by the vibration unit.

  The heating unit 17 provided in the groove 16 heats the inside of the groove 16 to a predetermined temperature, and promotes the heating reaction of the unreacted sediment powder that has fallen into the groove 16. Thereby, the unreacted deposit powder is vaporized, and the deposit magnetic field powder in the groove 16 is removed. In addition, the heating of the groove 16 by the heating unit 17 transfers heat to the slope component member 18, and the deposit powder remaining on the slope surface 18 </ b> A of the slope component member 18 is efficiently vaporized and removed. be able to. The cleaning process is performed as described above. When the cleaning process is performed, the next film forming process is started. The cleaning process may be performed each time the film forming process is performed, or may be performed once after the film forming process is performed a plurality of times, or the thickness of the deposit attached to the side wall in the chamber 11 is determined. May be performed after the thickness reaches a predetermined thickness.

  According to the first embodiment, the groove 16 is provided around the gas exhaust port 15 provided near the center of the bottom surface of the chamber 11 of the substrate processing apparatus 1, and the groove 16 can be heated by the heating unit 17. Therefore, when the film forming material adhered to the inner wall of the chamber 11 falls as the deposit powder during the cleaning process when the cleaning process in the chamber 11 is performed, the unreacted deposit powder is concentrated in the groove 16. Can be made. Then, the reaction between the deposit powder and the cleaning gas is promoted by the heating reaction, and the film forming material adhering to the inner wall of the chamber 11 can be efficiently removed. In addition, since such a structure can be easily provided in existing equipment, the load of introducing a new process can be reduced and the film forming material adhering to the inner wall of the chamber 11 can be effectively removed. It has the effect that it can be done. As a result, concerns such as clogging in the exhaust system 30 can be suppressed.

Embodiment 2. FIG.
FIG. 2 is a diagram schematically showing the structure of the groove around the gas exhaust port according to the second embodiment. In addition, the same code | symbol is attached | subjected to the component same as Embodiment 1, and the description is abbreviate | omitted. As shown in this figure, an orifice 25 is provided in the vicinity of the upper portion of the groove 16 provided around the gas exhaust port 15 as diffusion preventing means for preventing the diffusion of the deposit powder. The orifice 25 prevents the deposit powder trapped in the groove 16 from rising, and even if the deposit powder rises, the orifice 25 is blocked by the orifice 25 and reaches the gas exhaust port 15. Can be prevented.

  According to the second embodiment, since the orifice 25 is provided in the vicinity of the upper portion of the groove 16, even if the sediment powder that has fallen into the groove 16 has risen, the sooted sediment powder to the gas exhaust port 15. And the exhaust system, in particular the vacuum pump, can be prevented from being blocked or damaged.

  In the above description, the plasma CVD apparatus is described as an example of the substrate processing apparatus 1. However, the above-described embodiment is applied to all apparatuses in which deposits adhere to the inner wall of the chamber 11 during processing. Can do. For example, in addition to general CVD equipment, sputtering equipment, ALD (Atomic Layer Deposition) equipment, vacuum deposition equipment, laser ablation equipment and other film forming equipment, RIE (Reactive Ion Etching) equipment, ashing equipment, CDE (Chemical Dry) The present invention can also be applied to an etching apparatus such as an etching apparatus.

  In the above description, the case of removing deposits attached to the inner wall of the chamber 11 when the Si film is formed on the substrate has been described as an example. However, the present invention is not limited to the Si film. The above-described embodiment can be similarly applied to the case where deposits adhere to the inner wall of the chamber 11 by depositing or etching the above material.

  As described above, the substrate processing apparatus according to the present invention is useful for a film forming apparatus capable of forming a large-area thin film, and is particularly suitable for a plasma CVD apparatus.

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 10 Deposition processing part 11 Chamber 12 Stage 13 Shower head 13A Discharge hole 14 Insulating member 15 Gas exhaust port 16 Groove 17 Heating part 18 Inclined surface member 18A Inclined surface 19 Blocking member 20, 21 Gas supply port 25 Orifice 30 Exhaust system 31, 51, 61 Pipe 32 Vacuum pump 33 Valve 40 Gas supply system 50 Processing gas supply system 52, 62 Gas supply source 53, 63 Gas valve 60 Cleaning gas supply system

Claims (8)

A chamber;
Substrate holding means for holding the substrate in the chamber;
Cleaning gas supply means for supplying a cleaning gas into the chamber for removing deposits attached in the chamber by processing the substrate;
A discharge means for discharging the gas in the chamber from a gas discharge port provided in a bottom wall of the chamber;
In a substrate processing apparatus comprising:
A substrate processing apparatus comprising a groove around the gas discharge port in the chamber.   The substrate processing apparatus according to claim 1, further comprising a diffusion preventing unit that prevents diffusion of the deposit powder accumulated in the groove.   The substrate processing apparatus according to claim 1, further comprising a heating unit that heats the inside of the groove.   The substrate processing according to claim 1, wherein an end portion of the gas discharge port is provided at a position higher than an upper surface of the bottom wall in the vicinity of the groove of the chamber. apparatus.   The bottom wall of the chamber further includes a slope constituting member having an inclined surface that decreases from a side wall of the chamber toward a groove of the bottom wall. The substrate processing apparatus as described.   The substrate processing apparatus according to claim 5, further comprising a vibrating unit that vibrates the inclined surface.   The substrate processing apparatus according to claim 5, wherein the inclined surface is made of aluminum or an aluminum alloy.   The said bottom wall of the said chamber is inclined so that it may become low toward the formation position of the said groove | channel from the boundary with the side wall of the said chamber, The Claim 1 characterized by the above-mentioned. Substrate processing equipment.

Images