JP2020132942A - Film deposition apparatus, and film deposition method - Google Patents

Abstract

To reduce intrusion of impurities contained in ambient air into a treatment vessel.SOLUTION: A film deposition apparatus is equipped with a treatment vessel, a gas supply source, a preliminary film deposition chamber, and a heating unit. The gas supply source supplies a raw material gas for depositing a film containing a specified element to an object to be treated housed in the treatment vessel. The preliminary film deposition chamber is installed on a flow channel of the raw material gas supplied from the gas supply source into the treatment vessel. The heating unit heats the preliminary film deposition chamber to a temperature higher than the decomposition temperature of the raw material gas. The raw material gas supplied from the gas supply source passes through the preliminary film deposition chamber heated by the heating unit and is then supplied to the treatment vessel.SELECTED DRAWING: Figure 1

Description

Various aspects and embodiments of the present disclosure relate to film forming equipment and film forming methods.

For example, in Patent Document 1 below, conditions of growth temperature, flow rate of gas containing silicon, and growth pressure are determined so that the silicon film grows amorphous at a growth rate in a predetermined range. A technique for forming a silicon film on a substrate is disclosed. The conditions for forming a silicon film in the technique of Patent Document 1 below are a growth temperature of 620 ° C. or higher, a flow rate of a gas containing silicon of 0.9 slm or higher, and a growth pressure of 21 kPa or higher. It is stated that the amorphous silicon film can be grown in a short time at the growth temperature and the flow rate and growth pressure of the gas containing silicon determined in this way, which contributes to the improvement of productivity.

Japanese Unexamined Patent Publication No. 2003-324773

The present disclosure provides a film forming apparatus and a film forming method capable of reducing the invasion of impurities contained in the outside air into the processing container.

One aspect of the present disclosure is a film forming apparatus, which includes a processing container, a gas supply source, a preliminary film forming chamber, and a heating unit. The gas supply source is a source of raw material gas for forming a film containing a predetermined element on the object to be processed arranged in the processing container. The pre-deposition chamber is arranged in the middle of the flow path of the raw material gas supplied from the gas supply source into the processing container. The heating unit heats the preliminary film formation chamber to a temperature higher than the decomposition temperature of the raw material gas. Further, the raw material gas supplied from the gas supply source is supplied to the processing container through the preliminary film forming chamber heated by the heating unit.

According to various aspects and embodiments of the present disclosure, it is possible to reduce the intrusion of impurities contained in the outside air into the processing container.

FIG. 1 is a schematic cross-sectional view showing an example of a film forming apparatus according to an embodiment of the present disclosure. FIG. 2 is an enlarged cross-sectional view showing an example of the vicinity of the connection portion between the support plate and the exhaust duct. FIG. 3 is an enlarged cross-sectional view showing an example of the vicinity of the connection portion of the pipe. FIG. 4 is an enlarged cross-sectional view showing another example near the connection portion of the pipe. FIG. 5 is a diagram showing an example of the oxygen concentration of the silicon-containing film formed for each film forming condition. FIG. 6 is a flowchart showing an example of the film forming method according to the embodiment of the present disclosure.

Hereinafter, embodiments of the disclosed film forming apparatus and film forming method will be described in detail with reference to the drawings. The disclosed film forming apparatus and film forming method are not limited by the following embodiments.

By the way, when a predetermined film is laminated on the object to be treated, the content of oxygen or the like may affect the characteristics of the film depending on the properties of the laminated film. Therefore, it is preferable that the processing container on which the film is formed is airtight so that the air outside the processing container does not enter the processing container. However, the processing container is composed of a plurality of members, and outside air may enter from the connecting portion of each member. Further, even in the piping for introducing the processing gas into the processing container, outside air may enter at a portion where different pipes are connected to each other.

By interposing a sealing member such as an O-ring in the connecting portion of the member, the intrusion of outside air can be suppressed, but it is difficult to completely block the intrusion of outside air. In addition, depending on the type of gas used, it may be necessary to heat the piping that introduces the processing gas into the processing container, but the O-ring has a large gap between molecules due to thermal expansion due to the rise in temperature, and the usage environment. The higher the temperature, the higher the gas permeability. Therefore, it is required to further suppress the invasion of impurities contained in the outside air into the processing container.

Therefore, the present disclosure provides a technique capable of reducing the intrusion of impurities contained in the outside air into the processing container.

[Structure of film forming apparatus 1]
FIG. 1 is a schematic cross-sectional view showing an example of the film forming apparatus 1 according to the embodiment of the present disclosure. The film forming apparatus 1 is an apparatus for forming a predetermined film (for example, a silicon-containing film or the like) on a semiconductor wafer (hereinafter referred to as wafer W) which is an example of an object to be processed. The film forming apparatus 1 includes an apparatus main body 10 and a control device 100.

The apparatus main body 10 includes a processing container 11 which is a vacuum container for accommodating the wafer W and forming a film on the accommodated wafer W. The processing container 11 is formed in a substantially flat circular shape. An opening 12 for carrying in and out of the wafer W is formed on the side wall of the processing container 11. The opening 12 is opened and closed by the gate valve 13.

An exhaust duct 14 is provided on the upper side of the opening 12. The exhaust duct 14 forms a part of the side wall of the processing container 11, has a square shape with a hollow vertical cross section, and is configured to be curved in an annular shape along the side wall of the processing container 11. A slit-shaped exhaust port 15 extending along the extending direction of the exhaust duct 14 is formed on the inner peripheral surface of the exhaust duct 14. Further, one end of the exhaust pipe 16 is connected to the exhaust duct 14. The other end of the exhaust pipe 16 is connected to an exhaust device 17 having a vacuum pump or the like. Further, the exhaust pipe 16 is provided with a pressure adjusting unit 18 such as an APC (Auto Pressure Controller) valve. The pressure adjusting unit 18 is controlled by the control device 100 to control the pressure in the processing container 11 to a predetermined pressure. In the present embodiment, during the film forming process, the pressure inside the processing container 11 is controlled to, for example, 7.5 to 15 Torr.

A mounting table 31 on which the wafer W is mounted is provided in the processing container 11. An electrode 30 and a heater 32 are embedded inside the mounting table 31. The electrode 30 generates an electrostatic force on the surface of the mounting table 31 by a DC voltage applied from a DC power source (not shown), and attracts the wafer W to the upper surface of the mounting table 31 by the electrostatic force. The heater 32 heats the wafer W on the mounting table 31. In the present embodiment, the heater 32 heats the wafer W so that the temperature of the wafer W on the mounting table 31 is 500 ° C. or higher. The heater 32 is an example of the second heating unit.

The upper end of the support member 34 that penetrates the bottom of the processing container 11 and extends in the vertical direction is connected to substantially the center of the lower surface side of the mounting table 31. The lower end of the support member 34 is connected to the elevating mechanism 35. As the support member 34 moves up and down by the elevating mechanism 35, the mounting table 31 moves up and down between the lower position shown by the chain line in FIG. 1 and the upper position shown by the solid line in FIG. be able to. The position on the lower side is when the wafer W before processing is carried into the processing container 11 through the opening 12 by a transfer mechanism (not shown), and when the wafer W after processing is conveyed through the opening 12 (not shown). This is the delivery position when the wafer is carried out from the processing container 11 by the mechanism. The position on the upper side is a processing position when processing is performed on the wafer W.

The support member 34 is provided with a flange 36. The bottom of the processing container 11 and the flange 36 are connected by a bellows 37. As a result, the airtightness inside the processing container 11 is ensured even when the support member 34 is moved up and down by the elevating mechanism 35.

Further, a plurality of support pins 38 are provided on the bottom of the processing container 11. The elevating mechanism 39 elevates and elevates a plurality of support pins 38. For example, when the mounting table 31 is located at the delivery position, the elevating mechanism 39 raises the plurality of support pins 38. As a result, the support pin 38 pushes up the wafer W through the through hole 19 provided in the mounting table 31, and the wafer W can be delivered to and from a transfer mechanism (not shown).

A support plate 41 is provided on the upper side of the exhaust duct 14 so as to close the inside of the processing container 11 from the upper side. A seal member 52 and a seal member 53 are arranged between the support plate 41 and the exhaust duct 14. The seal member 52 and the seal member 53 are, for example, O-rings.

FIG. 2 is an enlarged cross-sectional view showing an example of the vicinity of the connection portion between the support plate 41 and the exhaust duct 14. A flow path 410 is formed in the support plate 41. The flow path 410 communicates with the space 412 between the seal member 52 and the seal member 53. Further, the space 412 is connected to the exhaust device 17 via the exhaust passage 411. A gas supply source 56 is connected to the flow path 410 via a valve 55. The gas supply source 56 is a source of an inert gas such as nitrogen gas or a rare gas.

By controlling the opening and closing of the valve 55, the control device 100 controls the pressure in the space 412 so that the pressure in the space 412 becomes a positive pressure. For example, the control device 100 controls the valve 55 to be in an open state, and adjusts the pressure of the inert gas to, for example, about 0.1 to 0.3 MPa by a regulator (not shown). Then, the control device 100 adjusts the flow rate of the inert gas in the space 412 by a flow meter (not shown), and purges the space 412 with the inert gas. The gas purged from the space 412 is exhausted from the exhaust passage 411. The control device 100 uses an oxygen concentration meter to measure the concentration of oxygen contained in the gas purged from the space 412. Then, when the concentration of oxygen contained in the gas purged from the space 412 exceeds a predetermined value, the control device 100 notifies the user or the like of the film forming apparatus 1 of an error.

Here, since the seal member 52 and the seal member 53 are arranged between the support plate 41 and the exhaust duct 14, the outside air into the processing container 11 from the gap between the support plate 41 and the exhaust duct 14 Invasion is suppressed. However, since the seal member 52 and the seal member 53 have a certain degree of gas permeability, it is difficult to completely block the intrusion of outside air into the processing container 11. In addition, the gas blocking property of the seal member 52 and the seal member 53 may decrease due to a temperature rise or a change with time of the seal member 52 and the seal member 53.

Therefore, in the present embodiment, the inert gas is filled in the space 412 between the seal member 52 and the seal member 53 interposed between the support plate 41 and the exhaust duct 14, and the pressure in the space 412 becomes a positive pressure. The pressure in the space 412 is controlled so as to be. As a result, the intrusion of outside air into the processing container 11 is suppressed.

The explanation will be continued by returning to FIG. A shower head 40 is provided on the lower surface side of the support plate 41. The ceiling portion of the processing container 11 is formed by the support plate 41 and the shower head 40. The shower head 40 has a top plate 42 and a shower plate 43. The top plate 42 holds the shower plate 43 detachably from above. A recess is formed substantially in the center of the lower surface side of the top plate 42.

Below the top plate 42, a plate-shaped shower plate 43 is provided so as to face the mounting table 31. The shower plate 43 is provided on the lower surface of the top plate 42 and covers the entire lower surface of the top plate 42. The shower plate 43 is formed with a plurality of discharge ports 46 penetrating in the thickness direction of the shower plate 43.

A gas introduction pipe 51 for introducing gas into the shower head 40 is provided at substantially the center of the upper surface side of the top plate 42. The gas introduction pipe 51 penetrates the support plate 41 and projects from the upper surface of the support plate 41. The gas introduced into the shower head 40 via the gas introduction pipe 51 diffuses in the diffusion chamber 44 surrounded by the recess of the top plate 42 and the shower plate 43. The gas diffused in the diffusion chamber 44 is supplied in a shower shape into the processing container 11 through the plurality of discharge ports 46. The diffusion chamber 44 is arranged in the middle of the flow path of the raw material gas supplied from the gas supply source 20 and the gas supply source 23 into the processing container 11. The diffusion chamber 44 is an example of a preliminary film formation chamber.

A heater 60 for heating the shower head 40 is provided between the support plate 41 and the shower head 40. The heater 60 heats the shower head 40 so that the temperature of the wall surface of the diffusion chamber 44 becomes higher than the decomposition temperature of the raw material gas described later when laminating a predetermined film on the wafer W. In the present embodiment, the heater 60 is arranged on the upper surface of the shower head 40 and heats the upper part of the shower head 40. The heater 60 is an example of the first heating unit.

A pipe 26 is connected to the gas introduction pipe 51 via a purge BOX 50. A gas supply source 56 is connected to the purge BOX 50 via a valve 54.

Here, the details of the purge BOX 50 will be described. FIG. 3 is an enlarged cross-sectional view showing an example of the vicinity of the connection portion of the pipe. For example, as shown in FIG. 3, the pipe 26 and the gas introduction pipe 51 are arranged in the purge BOX 50 and are connected via an insulating pipe 502. The insulating pipe 502 is made of, for example, an insulating resin or the like. As a result, the insulating property between the pipe 26 and the gas introduction pipe 51 is ensured.

The inert gas is supplied into the purge BOX 50 from the gas supply source 56 via the valve 54. An exhaust device 17 is connected to the purge BOX 50 via an exhaust passage 504. By controlling the opening and closing of the valve 54, the control device 100 controls the pressure in the purge BOX 50 so that the pressure in the purge BOX 50 becomes a positive pressure. For example, the control device 100 controls the valve 54 to be in an open state, and adjusts the pressure of the inert gas to, for example, about 0.1 to 0.3 MPa by a regulator (not shown). Then, the control device 100 adjusts the flow rate of the inert gas in the purge BOX 50 with a flow meter (not shown), and purges the purge BOX 50 with the inert gas. The gas purged from the purge BOX 50 is exhausted from the exhaust passage 504. The control device 100 measures the concentration of oxygen contained in the gas purged from the purged BOX 50 using an oxygen concentration meter. Then, when the concentration of oxygen contained in the gas purged from the purge BOX 50 exceeds a predetermined value, the control device 100 notifies the user of the film forming apparatus 1 and the like of an error.

A seal member 501 is arranged between the pipe 26 and the insulating pipe 502, and a seal member 503 is arranged between the insulated pipe 502 and the gas introduction pipe 51. The seal member 501 and the seal member 503 are, for example, O-rings. In the present embodiment, the pressure in the purge BOX 50 is such that the piping connected via the seal member is covered with the purge BOX 50, the purge BOX 50 is filled with the inert gas, and the pressure in the purge BOX 50 becomes a positive pressure. Is controlled. As a result, it is possible to suppress the intrusion of outside air into the inside of the gas introduction pipe 51.

The pipe 26 and the gas introduction pipe 51 may be connected in the form shown in FIG. 4, for example. FIG. 4 is an enlarged cross-sectional view showing another example near the connection portion of the pipe. In the example of FIG. 4, the seal member 501a and the seal member 501b are arranged between the pipe 26 and the insulation pipe 502, and the seal member 503a and the seal member 501b are arranged between the insulation pipe 502 and the gas introduction pipe 51. 503b is arranged.

Further, a flow path 505 is formed in the pipe 26, and the flow path 505 communicates with the space between the seal member 501a and the seal member 501b. The flow path 505 is supplied with an inert gas from the gas supply source 56 via the valve 54. Further, a flow path 506 is formed in the insulating pipe 502, and the flow path 506 communicates with the space between the seal member 501a and the seal member 501b and the space between the seal member 503a and the seal member 503b. are doing. Further, an exhaust passage 507 is formed in the gas introduction pipe 51, and the exhaust passage 507 communicates with the space between the seal member 503a and the seal member 503b. The exhaust passage 507 is connected to the exhaust device 17 via a pipe 508.

By controlling the opening and closing of the valve 54, the control device 100 makes the pressure in the space between the seal member 501a and the seal member 501b and the pressure in the space between the seal member 503a and the seal member 503b positive. The pressure in the flow path 506 is controlled in this way. Even with such a configuration, it is possible to suppress the intrusion of outside air into the inside of the gas introduction pipe 51.

The explanation will be continued by returning to FIG. A gas supply source 20 is connected to the pipe 26 via a valve 22 and a flow rate controller 21. The flow rate controller 21 controls the flow rate of gas flowing from the gas supply source 20 to the pipe 26 when the valve 22 is controlled to be in the open state.

The gas supply source 20 is a supply source for supplying a raw material gas for forming a film containing a predetermined element on the wafer W. In the present embodiment, the film formed on the wafer W is a silicon-containing film such as amorphous silicon, and the predetermined element is, for example, silicon. Further, in the present embodiment, the raw material gas supplied by the gas supply source 20 is, for example, monosilane gas. In the following, a monosilane gas will be described as a raw material gas, and a silicon-containing film as a film formed on the wafer W will be described as an example.

The raw material gas supplied by the gas supply source 20 may be another silicon-containing gas such as disilane gas, or may be a gas that does not contain silicon but contains other elements. Further, the film formed on the wafer W may be a film that does not contain silicon but contains other elements such as tungsten.

Further, a gas supply source 23 is connected to the pipe 26 via a valve 25 and a flow rate controller 24. The gas supply source 23 is a supply source for supplying cleaning gas for cleaning the inside of the diffusion chamber 44 and the processing container 11. The cleaning gas is, for example, NF3 gas. The flow rate controller 24 controls the flow rate of the cleaning gas flowing from the gas supply source 23 to the pipe 26 when the valve 25 is controlled to be in the open state.

A high frequency power supply 48 is connected to the shower plate 43 via a matching unit 47. The high-frequency power source 48 is a power source for plasma generation, and generates high-frequency power having a frequency of 13.56 MHz or higher, for example, 60 MHz. The high-frequency power generated by the high-frequency power supply 48 is supplied to the shower plate 43 via the matching unit 47. The matcher 47 matches the internal (or output) impedance of the high frequency power supply 48 with the load impedance.

The high-frequency power supplied to the shower plate 43 is radiated into the processing container 11 from the lower surface of the shower plate 43. The gas supplied into the processing space S surrounded by the shower plate 43 and the wafer W placed on the upper surface of the mounting table 31 through the plurality of discharge ports 46 has a high frequency radiated into the processing container 11. It is converted to plasma by electric power. The shower plate 43 and the electrodes 30 of the mounting table 31 form a pair and function as counter electrodes for forming capacitively coupled plasma (CCP) in the processing space S.

When the silicon-containing film is laminated on the wafer W, the monosilane gas supplied into the processing container 11 through the plurality of discharge ports 46 is turned into plasma by the high-frequency power radiated into the processing container 11. Then, the silicon-containing film is laminated on the wafer W held on the mounting table 31 by the charged particles and the active species contained in the plasmaized monosilane gas.

Further, when cleaning the inside of the diffusion chamber 44 and the processing container 11, cleaning gas is supplied into the diffusion chamber 44, and the silicon-containing film laminated in the diffusion chamber 44 is removed. Further, the cleaning gas supplied into the processing container 11 through the plurality of discharge ports 46 is turned into plasma by the high frequency power radiated into the processing container 11. Then, the reaction by-products adhering to the inner wall and the like of the processing container 11 are removed by the active species and the like contained in the plasmaized cleaning gas.

Here, when the silicon-containing film is laminated on the wafer W, the monosilane gas supplied from the gas supply source 20 is heated to a temperature higher than the decomposition temperature of the monosilane gas (for example, 500 ° C. or higher). Pass through. As a result, a part of the monosilane gas is thermally decomposed in the diffusion chamber 44, and a silicon-containing film is formed in the diffusion chamber 44.

At this time, impurities such as oxygen mixed in the supply path of the monosilane gas are taken into the silicon-containing film formed in the diffusion chamber 44. As a result, impurities such as oxygen mixed in the supply path of the monosilane gas are reduced in the monosilane gas flowing from the discharge port 46 of the shower plate 43 into the processing container 11. As a result, a silicon-containing film with few impurities can be formed on the wafer W in the processing space S below the shower plate 43.

When laminating the silicon-containing film on the wafer W, it is preferable that the diffusion chamber 44 is heated to a temperature higher than the decomposition temperature of the monosilane gas and lower than the temperature of the wafer W. As a result, it is possible to prevent the discharge port 46 of the shower plate 43 from being blocked due to the excessive silicon-containing film being laminated in the diffusion chamber 44. Further, it is possible to prevent the monosilane gas from being excessively consumed in the diffusion chamber 44 and the film forming rate of the silicon-containing film laminated on the wafer W from being lowered.

Further, in the present embodiment, the heater 60 heats the upper surface of the shower head 40. As a result, it is possible to form a temperature gradient in which the temperature of the top plate 42 is higher than the temperature of the shower plate 43 in the diffusion chamber 44. In the temperature range above the decomposition temperature of monosilane gas, the higher the temperature, the higher the film formation rate. Therefore, more silicon-containing film is formed on the top plate 42 side than on the shower plate 43 side in the diffusion chamber 44. As a result, it is possible to prevent the discharge port 46 of the shower plate 43 from being blocked by the silicon-containing film formed in the diffusion chamber 44.

The control device 100 has a processor, a memory, and an input / output interface. Programs, processing recipes, etc. are stored in the memory. The processor controls each part of the apparatus main body 10 via the input / output interface according to the processing recipe read from the memory by executing the program read from the memory.

[Experimental result]
FIG. 5 is a diagram showing an example of the oxygen concentration of the silicon-containing film formed for each film forming condition. In the experimental results illustrated in FIG. 5, the film forming apparatus 1 illustrated in FIG. 1 was used to variously change the film forming conditions such as the pressure in the processing container 11 and the flow rate of the monosilane gas to form a silicon-containing film. Was done. The comparative example illustrated in FIG. 5 is an experimental result when the diffusion chamber 44 is not heated by the heater 60.

As illustrated in FIG. 5, under all the film forming conditions, by heating the diffusion chamber 44, the oxygen concentration in the silicon-containing film is increased by one digit as compared with the comparative example in which the diffusion chamber 44 is not heated. It can be reduced to some extent.

[Film film processing]
FIG. 6 is a flowchart showing an example of the film forming method according to the embodiment of the present disclosure. The film forming method illustrated in FIG. 6 is realized mainly by the control device 100 controlling each part of the device main body 10.

First, the control device 100 controls the elevating mechanism 35, lowers the mounting table 31 to the delivery position, controls the elevating mechanism 39, and raises the plurality of support pins 38. Then, the gate valve 13 is opened, and the unprocessed wafer W is carried into the processing container 11 by a transfer mechanism (not shown) (S10). Then, the gate valve 13 is closed. The control device 100 controls the elevating mechanism 39 to lower the plurality of support pins 38. As a result, the wafer W is placed on the mounting table 31. Then, the control device 100 controls the elevating mechanism 35 to raise the mounting table 31 to the processing position.

Next, the control device 100 controls the valve 54 in the open state and starts supplying the inert gas into the purge BOX 50 (S11). After that, the control device 100 controls the pressure in the purge BOX 50 so that the pressure in the purge BOX 50 becomes a positive pressure by controlling the opening and closing of the valve 54 and the like.

Similarly, the control device 100 controls the valve 55 in the open state and starts supplying the inert gas into the space 412 between the seal member 52 and the seal member 53 (S11). After that, the control device 100 controls the pressure in the space 412 so that the pressure in the space 412 becomes a positive pressure by controlling the opening and closing of the valve 55 and the like.

Next, the control device 100 controls the exhaust device 17 and the pressure adjusting unit 18 to evacuate the inside of the processing container 11 (S12). Then, the control device 100 controls the heater 32 and the heater 60, and starts heating the wafer W and the diffusion chamber 44 (S13).

Next, the control device 100 refers to the measured value of the temperature sensor (not shown) provided on the mounting table 31 and the measured value of the temperature sensor (not shown) provided on the top plate 42, and refers to the wafer W and the diffusion. It is determined whether or not each of the chambers 44 has reached a predetermined temperature (S14). In the present embodiment, the wafer W is heated to, for example, 580 ° C, and the diffusion chamber 44 is heated to, for example, 500 ° C. If at least one of the wafer W and the diffusion chamber 44 has not reached a predetermined temperature (S14: No), the process of step S14 is executed again. Steps S13 and S14 are examples of heating steps.

When the wafer W and the diffusion chamber 44 each reach a predetermined temperature (S14: Yes), the control device 100 executes the film forming process (S15). In the film forming process, the valve 22 is controlled to be in the open state, and the monosilane gas whose flow rate is controlled by the flow rate controller 21 is supplied to the processing space S via the shower head 40. At that time, impurities such as oxygen mixed in the supply path of the monosilane gas are taken into the silicon-containing film formed in the diffusion chamber 44 heated to a predetermined temperature, and the silicon-containing film having few impurities is taken on the wafer W. Is formed. Step S15 is an example of the film forming process.

When the film forming process is completed, the control device 100 controls the elevating mechanism 35, lowers the mounting table 31 to the delivery position, controls the elevating mechanism 39, and raises the plurality of support pins 38. Then, the gate valve 13 is opened, and the wafer W on which the silicon-containing film is formed is carried out from the processing container 11 by a transfer mechanism (not shown) (S16).

Next, the control device 100 determines whether or not there is an unprocessed wafer W (S17). When there is no unprocessed wafer W (S17: No), the film forming method shown in this flowchart is completed. On the other hand, when there is an untreated wafer W (S17: Yes), the control device 100 is exhausted from the space 412 between the seal member 52 and the seal member 53, the purge BOX 50, and the like using an oxygen concentration meter. Measure the concentration of oxygen contained in the exhaust gas. Then, the control device 100 determines whether or not the oxygen concentration contained in the gas purged from the purge BOX 50 is less than a predetermined value (S18).

When the oxygen concentration contained in the purged gas is less than a predetermined value (S18: Yes), the process shown in step S10 is executed again. On the other hand, when the oxygen concentration contained in the purged gas is equal to or higher than a predetermined value (S18: No), the control device 100 notifies the user or the like of the film forming apparatus 1 of an error (S19), and is shown in this flowchart. The film forming method is completed.

The embodiment has been described above. As described above, the film forming apparatus 1 of the present embodiment includes a processing container 11, a gas supply source 20, a preliminary film forming chamber, and a heater 60. The gas supply source 20 is a source of raw material gas for forming a film containing a predetermined element on the wafer W arranged in the processing container 11. The pre-deposition chamber is arranged in the middle of the flow path of the raw material gas supplied from the gas supply source 20 and the gas supply source 23 into the processing container 11. The heater 60 heats the preliminary film forming chamber to a temperature higher than the decomposition temperature of the raw material gas. Further, the raw material gas supplied from the gas supply source 20 is supplied into the processing container 11 through the preliminary film forming chamber heated by the heater 60. As a result, it is possible to reduce the intrusion of impurities contained in the outside air into the processing container.

Further, in the above-described embodiment, the predetermined element is silicon. This makes it possible to reduce the amount of oxygen mixed in the film formation of the silicon-containing film.

Further, in the above-described embodiment, the film forming apparatus 1 is provided in the upper part of the processing container 11 and is provided in a diffusion chamber 44 for diffusing the gas supplied from the gas supply source 20 and a plurality of diffusion chambers 44 provided in the lower part of the diffusion chamber 44. A shower head 40 having a discharge port 46 of the above is provided. The pre-deposition chamber is a diffusion chamber 44. The heater 60 heats the diffusion chamber 44 by heating the shower head 40. As a result, it is possible to reduce the intrusion of impurities contained in the outside air into the processing container.

Further, in the above-described embodiment, the heater 60 heats the upper part of the shower head 40. As a result, it is possible to prevent the discharge port 46 of the shower plate 43 from being blocked by the silicon-containing film formed in the diffusion chamber 44.

Further, in the above-described embodiment, the film forming apparatus 1 is provided inside the mounting table 31 on which the wafer W is mounted, and includes a heater 32 for heating the wafer W mounted on the mounting table 31. The heater 60 heats the diffusion chamber 44 so that the temperature is higher than the decomposition temperature of the raw material gas and lower than the temperature of the wafer W heated by the heater 32. As a result, it is possible to suppress a decrease in the film formation rate of the silicon-containing film laminated on the wafer W.

Further, the film forming method in the above-described embodiment includes a heating step and a film forming step. In the heating step, the wafer W arranged in the processing container 11 is arranged between the gas supply source 20 which is a supply source of the raw material gas for forming a film containing a predetermined element and the processing container 11. The diffusion chamber 44 is heated to a temperature higher than the decomposition temperature of the raw material gas. In the film forming step, the raw material gas is supplied from the gas supply source 20 into the processing container 11 via the heated diffusion chamber 44, so that the wafer W arranged in the processing container 11 contains a predetermined element. A film is formed. As a result, a film having few impurities can be formed.

[Other]
The technique disclosed in the present application is not limited to the above-described embodiment, and many modifications can be made within the scope of the gist thereof.

For example, in the above-described embodiment, the shower head 40 is heated by the heater 60, and the film is formed in the diffusion chamber 44 of the shower head 40 to remove impurities mixed in the supply path of the raw material gas. However, the disclosed technology is not limited to this. For example, impurities mixed in the supply path of the raw material gas may be removed by heating the gas introduction pipe 51 and forming a film in the gas introduction pipe 51. Even when the film is formed in the gas introduction pipe 51, the film formed in the gas introduction pipe 51 can be removed by supplying the cleaning gas into the gas introduction pipe 51.

Further, in the above-described embodiment, the heater 60 heats the shower head 40 so that the temperature in the diffusion chamber 44 is lower than the temperature of the wafer W, but the disclosed technique is not limited to this. For example, the heater 60 may heat the shower head 40 so that the temperature inside the diffusion chamber 44 is higher than the temperature of the wafer W. By doing so, the film formation rate in the diffusion chamber 44 increases, a large amount of impurities are taken into the film formed in the diffusion chamber 44, and a film having few impurities is formed on the wafer W. can do.

Further, in the above-described embodiment, capacitively coupled plasma (CCP) is used as an example of the plasma source, but the disclosed technique is not limited to this. As the plasma source, for example, inductively coupled plasma (ICP), microwave-excited surface wave plasma (SWP), electron cycloton resonance plasma (ECP), helicon wave-excited plasma (HWP), or the like may be used.

Further, in the film forming apparatus 1 of the above-described embodiment, high-frequency power for plasma generation is supplied to the shower head 40, but the disclosed technique is not limited to this, and high-frequency power for plasma generation is supplied to the electrode 30. May be done.

Further, in the above-described embodiment, the film forming apparatus 1 using plasma has been described as an example of the film forming apparatus, but the disclosed technique is not limited to this. For example, the disclosed technique can be applied to a thermal CVD (Chemical Vapor Deposition) apparatus that does not use plasma.

Further, in the above-described embodiment, the seal member 52, the seal member 53, the seal member 501, the seal member 503, and the like are O-rings made of an elastomer such as rubber, but the disclosed technique is not limited thereto. .. The seal member 52, the seal member 53, the seal member 501, the seal member 503, and the like may be metal gaskets. As a result, it is possible to further reduce the intrusion of impurities contained in the outside air into the processing container 11.

Further, in the above-described embodiment, the space 412 between the seal member 52 and the seal member 53 and the exhaust device 17 are connected, and the gas in the space 412 is evacuated before the inert gas is supplied into the space 412. It may be evacuated. As a result, the air remaining in the space 412 can be quickly replaced with the inert gas.

Further, in the above-described embodiment, the purge BOX 50 and the exhaust device 17 may be connected to vacuum exhaust the gas in the purge BOX 50 before the inert gas is supplied into the purge BOX 50. As a result, the air remaining in the purge BOX 50 can be quickly replaced with the inert gas.

It should be noted that the embodiments disclosed this time are examples in all respects and are not restrictive. Indeed, the above embodiments can be embodied in a variety of forms. In addition, the above-described embodiment may be omitted, replaced, or changed in various forms without departing from the scope of the appended claims and the gist thereof.

S Processing space W Wafer 1 Film formation device 10 Equipment body 11 Processing container 14 Exhaust duct 20 Gas supply source 23 Gas supply source 26 Piping 30 Electrode 31 Mounting stand 32 Heater 40 Shower head 41 Support plate 42 Top plate 43 Shower plate 44 Diffusion chamber 46 Discharge port 50 Purge BOX
51 Gas introduction pipe 52 Seal member 53 Seal member 54 Valve 55 Valve 56 Gas supply source 60 Heater 100 Control device

Claims (6)

Processing container and
A gas supply source that is a source of raw material gas for forming a film containing a predetermined element on an object to be treated arranged in the processing container, and
A pre-deposition chamber arranged in the middle of the flow path of the raw material gas supplied from the gas supply source into the processing container, and
The pre-deposition chamber is provided with a first heating unit that heats the raw material gas to a temperature higher than the decomposition temperature of the raw material gas.
The film forming apparatus in which the raw material gas supplied from the gas supply source is supplied into the processing container through the preliminary film forming chamber heated by the first heating unit. The film forming apparatus according to claim 1, wherein the predetermined element is silicon. A shower head provided in the upper part of the processing container and having a diffusion chamber for diffusing the gas supplied from the gas supply source and a plurality of discharge ports provided in the lower part of the diffusion chamber is provided.
The pre-deposition chamber is the diffusion chamber.
The film forming apparatus according to claim 1 or 2, wherein the first heating unit heats the diffusion chamber by heating the shower head. The first heating unit is
The film forming apparatus according to claim 3, wherein the upper part of the shower head is heated. It is provided inside a mounting table on which the object to be processed is placed, and includes a second heating unit for heating the object to be processed mounted on the above-mentioned table.
The first heating unit is
Claims 1 to 3 in which the preliminary film forming chamber is heated so as to be higher than the decomposition temperature of the raw material gas and lower than the temperature of the object to be processed heated by the second heating unit. The film forming apparatus according to any one item. The flow path of the raw material gas supplied into the processing container from the gas supply source which is the source of the raw material gas for forming a film containing a predetermined element on the object to be processed arranged in the processing container. A heating step of heating the preliminary film forming chamber arranged in the middle to a temperature higher than the decomposition temperature of the raw material gas, and
By supplying the raw material gas from the gas supply source into the processing container via the heated pre-deposition chamber, the object to be processed contained in the processing container contains the predetermined element. A film forming method including a film forming step of forming a film to be formed.

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