Film forming method and film forming apparatus

Abstract

To provide a technique capable of improving a deposition rate when forming a silicon-containing film at a low temperature.SOLUTION: According to an aspect of the present disclosure, there is provided a film forming method including loading a plurality of substrates into a process container, heating an inside of the process container by a container heating unit provided around the process container, and heating a first precursor gas in a first gas nozzle by a gas heating unit included in the first gas nozzle. And repeating a cycle a plurality of times, the cycle including supplying the heated first precursor gas from the first gas nozzle into the process container, supplying a first reaction gas that reacts with the first precursor gas from a second gas nozzle into the process container, supplying the first precursor gas, and supplying the first reaction gas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a film formation method and a film formation apparatus. [Background technology]

[0002] A technology has been disclosed in which dichlorosilane and oxidizing gas radicals are alternately supplied into a reaction chamber to form a silicon oxynitride film on a substrate in the reaction chamber (see, for example, Patent Document 1).A technology has also been disclosed in which, when a source gas obtained by vaporizing a liquid source is supplied from a gas nozzle into a reaction vessel, the source gas is preheated by a preheater provided in the gas nozzle, so that the source gas can be supplied into the reaction vessel without condensing (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-19145 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-81365 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can improve the deposition rate when forming a silicon-containing film at a low temperature. [Means for solving the problem]

[0005] A film formation method according to one aspect of the present disclosure includes: loading a plurality of substrates into a processing vessel; heating the processing vessel using a vessel heating unit disposed around the processing vessel; heating a first source gas in a first gas nozzle using a gas heating unit included in the first gas nozzle; supplying the heated first source gas from the first gas nozzle into the processing vessel; supplying a first reaction gas that reacts with the first source gas from a second gas nozzle into the processing vessel; and repeating a cycle including supplying the first source gas and supplying the first reaction gas multiple times. [Effects of the Invention]

[0006] According to the present disclosure, the film formation rate can be improved when forming a silicon-containing film at a low temperature. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a vertical cross-sectional view showing a film forming apparatus according to an embodiment. [Figure 2] 1 is a horizontal cross-sectional view showing a film forming apparatus according to an embodiment. [Figure 3] FIG. 2 is a cross-sectional view showing an example of a gas nozzle included in the film forming apparatus according to the embodiment. [Figure 4] 4 is a timing chart showing a film forming method according to a first example of the embodiment. [Figure 5] 6 is a timing chart showing a film forming method according to a second example of the embodiment. [Figure 6] 10 is a timing chart showing a film forming method according to a third example of the embodiment. [Figure 7] FIG. 10 is a diagram showing the measurement results of the thickness of a silicon nitride film. [Figure 8] FIG. 10 is a diagram showing the measurement results of the film formation rate of a silicon nitride film. [Figure 9] FIG. 10 is a diagram showing the measurement results of WER of a silicon nitride film. [Figure 10] FIG. 10 is a diagram showing the measurement results of the stress of a silicon nitride film. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, non-limiting exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. In all the accompanying drawings, the same or corresponding reference numerals are used to designate the same or corresponding members or components, and redundant descriptions will be omitted.

[0009] [Film forming equipment] A film forming apparatus 1 according to an embodiment will be described with reference to Figures 1 and 2. Figure 1 is a vertical cross-sectional view showing the film forming apparatus 1 according to an embodiment. Figure 2 is a horizontal cross-sectional view showing the film forming apparatus 1 according to an embodiment.

[0010] The film forming apparatus 1 is a batch type apparatus that processes a plurality of substrates W at once. The substrates W are, for example, semiconductor wafers. The film forming apparatus 1 includes a processing chamber 10, a gas supply unit 30, an exhaust unit 40, a chamber heating unit 50, and a control unit 90.

[0011] The processing vessel 10 can have its interior depressurized. The processing vessel 10 accommodates a substrate W. The processing vessel 10 has an inner tube 11 and an outer tube 12. The inner tube 11 has a cylindrical shape with a ceiling and an open lower end. The outer tube 12 has a cylindrical shape with a ceiling and an open lower end that covers the outside of the inner tube 11. The inner tube 11 and the outer tube 12 are made of a heat-resistant material such as quartz. The inner tube 11 and the outer tube 12 have a double-tube structure arranged coaxially.

[0012] A storage section 13 for storing a gas supply pipe is formed along the longitudinal direction (vertical direction) on the side wall of the inner pipe 11. For example, a part of the side wall of the inner pipe 11 is protruded outward to form a convex section 14, and the inside of the convex section 14 is formed as the storage section 13.

[0013] A rectangular opening 15 is formed along the longitudinal direction in the side wall of the inner tube 11. The opening 15 faces the storage portion 13.

[0014] The opening 15 is a gas exhaust port formed so as to be able to exhaust gas from the inner tube 11. The length of the opening 15 is the same as the length of the boat 16, or is formed so as to extend in the vertical direction and be longer than the length of the boat 16.

[0015] The lower end of the processing vessel 10 is supported by a cylindrical manifold 17. The manifold 17 is made of, for example, stainless steel. A flange 18 is formed at the upper end of the manifold 17. The flange 18 supports the lower end of the outer tube 12. A seal member 19, such as an O-ring, is provided between the flange 18 and the lower end of the outer tube 12. This keeps the inside of the outer tube 12 airtight.

[0016] An annular support member 20 is provided on the inner wall of the upper portion of the manifold 17. The support member 20 supports the lower end of the inner tube 11. A lid member 21 is airtightly attached to the opening at the lower end of the manifold 17 via a sealing member 22 such as an O-ring. This airtightly closes the opening at the lower end of the processing vessel 10, i.e., the opening of the manifold 17. The lid member 21 is made of, for example, stainless steel.

[0017] A rotating shaft 24 is provided in the center of the lid 21, penetrating through the lid 21 via a magnetic fluid seal 23. The lower part of the rotating shaft 24 is rotatably supported by an arm 25A of an elevation mechanism 25 made up of a boat elevator.

[0018] A rotating plate 26 is provided at the upper end of the rotating shaft 24. A boat 16 holding substrates W is placed on the rotating plate 26 via a quartz heat retention stand 27. The boat 16 rotates by rotating the rotating shaft 24. The boat 16 moves up and down integrally with the lid 21 by raising and lowering the lifting mechanism 25. This allows the boat 16 to be inserted into and removed from the processing vessel 10. The boat 16 can be accommodated within the processing vessel 10. The boat 16 holds multiple (e.g., 50 to 150) substrates W in a shelf-like manner. The boat 16 holds the multiple substrates W approximately horizontally with spacing between them in the vertical direction.

[0019] The gas supply unit 30 supplies various gases into the inner tube 11. The gas supply unit 30 has a gas nozzle 31 and a gas nozzle 32. The gas nozzle 31 is an example of a first gas nozzle. The gas nozzle 32 is an example of a second gas nozzle. The gas nozzle 31 and the gas nozzle 32 are made of, for example, quartz. The gas supply unit 30 may further have another gas nozzle.

[0020] The gas nozzle 31 is fixed to the manifold 17. The gas nozzle 31 extends linearly in the vertical direction near the inner tube 11, and then bends in an L-shape within the manifold 17, extending horizontally and penetrating the manifold 17. A plurality of gas holes 31h are provided in a portion of the gas nozzle 31 located within the inner tube 11. The gas holes 31h are provided at predetermined intervals along the vertical direction. Each gas hole 31h ejects gas horizontally toward the substrate W from outside in the radial direction of the substrate W. Each gas hole 31h ejects gas parallel to the main surface of the substrate W.

[0021] A supply path L11 is connected to the gas nozzle 31. A source gas supply source G11, a mass flow controller F11, and a valve V11 are provided on the supply path L11, in this order from upstream to downstream in the gas flow direction. The source gas contains dichlorosilane (DCS) and ethylene (C2H4). Dichlorosilane is an example of a first source gas. Ethylene is an example of a second source gas. The supply timing of the source gas from the supply source G11 is controlled by the valve V11, and the flow rate is adjusted to a predetermined value by the mass flow controller F11. The source gas flows from the supply path L11 into the gas nozzle 31 and is discharged into the inner tube 11 through a plurality of gas holes 31h.

[0022] A supply path L12 is connected to the supply path L11 downstream of the valve V11. A purge gas supply source G12, a mass flow controller F12, and a valve V12 are provided in this order from upstream to downstream in the gas flow direction. The purge gas contains nitrogen (N2). The supply timing of the purge gas from the supply source G12 is controlled by the valve V12, and the mass flow controller F12 adjusts the flow rate to a predetermined value. The purge gas flows from the supply path L12 into the gas nozzle 31 and is discharged into the inner pipe 11 through multiple gas holes 31h.

[0023] The gas nozzle 32 is fixed to the manifold 17. The gas nozzle 32 extends linearly in the vertical direction near the inner pipe 11, and then bends in an L-shape within the manifold 17, extending horizontally and penetrating the manifold 17. The gas nozzle 32 is provided alongside the gas nozzle 31 in the circumferential direction of the inner pipe 11. A plurality of gas holes 32h are provided in a portion of the gas nozzle 32 located within the inner pipe 11. The gas holes 32h are provided at predetermined intervals in the vertical direction. Each gas hole 32h ejects gas horizontally toward the substrate W from outside in the radial direction of the substrate W. Each gas hole 32h ejects gas parallel to the main surface of the substrate W.

[0024] A supply path L21 is connected to the gas nozzle 32. A reactive gas supply source G21, a mass flow controller F21, and a valve V21 are provided on the supply path L21, in this order from upstream to downstream in the gas flow direction. The reactive gas contains ammonia (NH3) and ozone (O3). Ammonia is an example of a first reactive gas. Ozone is an example of a second reactive gas. The supply timing of the reactive gas from the supply source G21 is controlled by the valve V21, and the flow rate is adjusted to a predetermined value by the mass flow controller F21. The reactive gas flows from the supply path L21 into the gas nozzle 32 and is discharged into the inner tube 11 through multiple gas holes 32h.

[0025] The exhaust unit 40 exhausts gas that is discharged from the inner tube 11 through the opening 15 and then discharged from a gas outlet 41 via a space P1 between the inner tube 11 and the outer tube 12. The gas outlet 41 is formed on the side wall of the upper part of the manifold 17, above the support unit 20. An exhaust flow path 42 is connected to the gas outlet 41. A pressure adjustment valve 43 and a vacuum pump 44 are sequentially disposed in the exhaust flow path 42, so that the inside of the processing chamber 10 can be exhausted.

[0026] The container heating part 50 is provided around the outer tube 12. The container heating part 50 is provided, for example, on the base plate 28. The container heating part 50 has a cylindrical shape so as to cover the outer tube 12. The container heating part 50 includes, for example, a heating element, and heats the inside of the processing container 10 and each substrate W in the processing container 10.

[0027] The control unit 90 is an electronic circuit such as a CPU (Central Processing Unit), FPGA (Field Programmable Gate Array), ASIC (Application Specific Integrated Circuit), etc. The control unit 90 executes various control operations described in this specification by executing instruction codes stored in a memory or by being a circuit designed for a specific application.

[0028] [Gas nozzle] An example of the gas nozzle 31 included in the film formation apparatus 1 will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing an example of the gas nozzle 31 included in the film formation apparatus 1 according to the embodiment.

[0029] The gas nozzle 31 has an inner tube 210, an outer tube 220, and an adapter 230. The outer tube 220 and the adapter 230 are connected via a seal 235. The inner tube 210 is disposed inside the outer tube 220 and the adapter 230. An alumina core 201, a heating element 202, and a flexible cable 203 are provided inside the inner tube 210. The heating element 202 is wound around the alumina core 201. The flexible cable 203 connects the heating element 202 to a heater power supply (not shown). The heater power supply supplies power to the heating element 202 via the flexible cable 203. This causes the heating element 202 to generate heat, thereby heating the alumina core 201.

[0030] The source gas supplied from the supply port 231 of the adapter 230 passes through the space between the inner tube 210 and the adapter 230 and the space between the inner tube 210 and the outer tube 220, and is discharged from the gas hole 31h. Furthermore, when power is supplied from a heater power supply to the heating element 202, the source gas is heated, and the heated source gas is discharged from the gas hole 31h. Thus, the gas nozzle 31 includes the outer tube 220 through which the source gas flows, and a gas heating unit disposed within the outer tube 220 for heating the source gas flowing through the outer tube 220. The gas heating unit includes an alumina core 201 and a heating element 202. The gas heating unit is disposed within the outer tube 220, which is disposed within the inner tube 11.

[0031] [Film formation method] (Example 1) A film formation method according to a first example of an embodiment will be described with reference to Fig. 4. Fig. 4 is a timing chart showing the film formation method according to the first example of an embodiment. The film formation method according to the first example is a method for forming a silicon nitride (SiN) film by atomic layer deposition (ALD) in which dichlorosilane and ammonia are supplied non-simultaneously. The film formation method according to the first example is performed under the control of a control unit 90.

[0032] First, the control unit 90 raises the arm 25A to load the boat 16 holding the substrates W into the processing vessel 10, and then airtightly closes the opening at the bottom of the processing vessel 10 with the lid 21. Next, the control unit 90 controls the exhaust unit 40 so that the pressure inside the processing vessel 10 is set to a set value, and controls the vessel heating unit 50 so that the temperature inside the processing vessel 10 is set to a desired value.

[0033] Next, the control unit 90 executes a film formation process in the processing chamber 10 to form a silicon nitride film on the surface of each substrate W by atomic layer deposition using non-simultaneous supply of dichlorosilane and ammonia.

[0034] At time t11, the gas nozzle 31 starts supplying dichlorosilane into the inner tube 11. As a result, dichlorosilane is adsorbed onto the surface of each substrate W. At time t11, the gas heater starts heating the gas nozzle 31. As a result, dichlorosilane is heated in the gas nozzle 31 and supplied into the inner tube 11. The set temperature of the gas heater may be higher than the set temperature of the container heater 50, for example. At time t11, the gas nozzle 31 starts supplying nitrogen into the inner tube 11.

[0035] At time t12, the gas nozzle 31 stops supplying dichlorosilane into the inner tube 11. Heating of the gas nozzle 31 by the gas heater continues after time t12. Heating of the gas nozzle 31 by the gas heater continues, for example, until the film formation process is completed. Supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues after time t12. Supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues, for example, until the film formation process is completed. During the period from time t12 to time t13, supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues. As a result, dichlorosilane remaining in the inner tube 11 is replaced with nitrogen. That is, the inside of the inner tube 11 is purged.

[0036] At time t13, the gas nozzle 32 starts supplying ammonia into the inner tube 11. The ammonia is activated by being heated by the container heating unit 50 as it flows through the gas nozzle 32. The activated ammonia nitrides the dichlorosilane adsorbed on the surface of each substrate W.

[0037] At time t14, the gas nozzle 32 stops supplying ammonia into the inner pipe 11. During the period from time t14 to time t15, the gas nozzle 31 continues to supply nitrogen into the inner pipe 11. As a result, the ammonia remaining in the inner pipe 11 is replaced with nitrogen. In other words, the inside of the inner pipe 11 is purged.

[0038] Next, the process from time t11 to time t15 is defined as an ALD cycle, and the ALD cycle is repeated multiple times, thereby forming a silicon nitride film on the surface of each of the substrates W held in the boat 16.

[0039] Next, the control unit 90 increases the pressure inside the processing vessel 10 to atmospheric pressure, and decreases the temperature inside the processing vessel 10 to the unloading temperature, and then lowers the arm 25A to unload the boat 16 from the processing vessel 10. This completes the film formation process on the multiple substrates W.

[0040] According to the film formation method of the first example, dichlorosilane is activated in the gas nozzle 31 by heating with the gas heating unit, and the activated dichlorosilane is supplied into the inner tube 11. This improves the reactivity of dichlorosilane. As a result, the film formation rate can be improved when forming a silicon nitride film at a low temperature. Furthermore, since dichlorosilane in the gas nozzle 31 can be heated by a gas heating unit provided separately from the container heating unit 50, the set temperature of the container heating unit 50 can be lowered. This reduces the thermal history that the substrate W processed in the inner tube 11 is subjected to. Thus, according to the film formation method of the first example, it is possible to achieve both a reduction in the thermal history and an improvement in the reactivity of dichlorosilane.

[0041] 4, the gas nozzle 31 is heated by the gas heater from time t11 until the film formation process is completed, but the timing at which the gas heater heats the gas nozzle 31 is not limited to this. For example, the gas heater may heat the gas nozzle 31 at the same time that the gas nozzle 31 supplies dichlorosilane into the inner tube 11. That is, the gas heater may heat the gas nozzle 31 during the period from time t11 to time t12. For example, the gas heater may start heating the gas nozzle 31 before time t11.

[0042] (Example 2) A film formation method according to a second example of the embodiment will be described with reference to FIG. 5. FIG. 5 is a timing chart showing the film formation method according to the second example of the embodiment. The film formation method according to the second example differs from the film formation method according to the first example in that ozone is used instead of ammonia. Other configurations of the film formation method according to the second example are the same as those of the film formation method according to the first example. That is, the film formation method according to the second example is a method for forming a silicon oxide (SiO2) film by atomic layer deposition in which dichlorosilane and ammonia are supplied non-simultaneously.

[0043] According to the film formation method of the second example, dichlorosilane is activated in the gas nozzle 31 by heating with the gas heating unit, and the activated dichlorosilane is supplied into the inner tube 11. This improves the reactivity of dichlorosilane. As a result, the film formation rate can be improved when forming a silicon oxide film at a low temperature. Furthermore, since dichlorosilane in the gas nozzle 31 can be heated by a gas heating unit provided separately from the container heating unit 50, the set temperature of the container heating unit 50 can be lowered. This reduces the thermal history that the substrate W processed in the inner tube 11 is subjected to. Thus, according to the film formation method of the second example, it is possible to achieve both a reduction in the thermal history and an improvement in the reactivity of dichlorosilane.

[0044] 5, the gas nozzle 31 is heated by the gas heater from time t11 until the film formation process is completed, but the timing at which the gas heater heats the gas nozzle 31 is not limited to this. For example, the gas heater may heat the gas nozzle 31 at the same time that the gas nozzle 31 supplies dichlorosilane into the inner tube 11. That is, the gas heater may heat the gas nozzle 31 during the period from time t11 to time t12. For example, the gas heater may start heating the gas nozzle 31 before time t11.

[0045] (Example 3) A film formation method according to a third example of the embodiment will be described with reference to FIG. 6. FIG. 6 is a timing chart showing the film formation method according to the third example of the embodiment. The film formation method according to the third example is a method for forming an SiOCN film by atomic layer deposition in which dichlorosilane, ethylene, ammonia, and ozone are supplied non-simultaneously. The film formation method according to the third example is performed under the control of a control unit 90.

[0046] First, the control unit 90 raises the arm 25A to load the boat 16 holding the substrates W into the processing vessel 10, and then airtightly closes the opening at the bottom of the processing vessel 10 with the lid 21. Next, the control unit 90 controls the exhaust unit 40 so that the pressure inside the processing vessel 10 is set to a set value, and controls the vessel heating unit 50 so that the temperature inside the processing vessel 10 is set to a desired value.

[0047] Next, the control unit 90 executes a film formation process in the processing chamber 10 to form an SiOCN film on the surface of each substrate W by atomic layer deposition using non-simultaneous supply of dichlorosilane, ethylene, ammonia, and ozone.

[0048] At time t31, the gas nozzle 31 starts supplying dichlorosilane into the inner tube 11. As a result, dichlorosilane is adsorbed onto the surface of each substrate W. At time t31, the gas heater starts heating the gas nozzle 31. As a result, dichlorosilane is heated in the gas nozzle 31 and supplied into the inner tube 11. The set temperature of the gas heater may be higher than the set temperature of the container heater 50, for example. At time t31, the gas nozzle 31 starts supplying nitrogen into the inner tube 11.

[0049] At time t32, the gas nozzle 31 stops supplying dichlorosilane into the inner tube 11. Heating of the gas nozzle 31 by the gas heater continues after time t32. Heating of the gas nozzle 31 by the gas heater continues, for example, until the film formation process is completed. Supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues after time t32. Supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues, for example, until the film formation process is completed. During the period from time t32 to time t33, supply of nitrogen from the gas nozzle 31 into the inner tube 11 continues. As a result, dichlorosilane remaining in the inner tube 11 is replaced with nitrogen. That is, the inside of the inner tube 11 is purged.

[0050] At time t33, the gas nozzle 31 starts supplying ethylene into the inner tube 11. As a result, ethylene is adsorbed onto the surface of each substrate W. At this time, since the gas nozzle 31 continues to be heated by the gas heater, the ethylene is heated in the gas nozzle 31 and supplied into the inner tube 11.

[0051] At time t34, the gas nozzle 31 stops supplying ethylene into the inner pipe 11. During the period from time t34 to time t35, the gas nozzle 31 continues to supply nitrogen into the inner pipe 11. As a result, the ethylene remaining in the inner pipe 11 is replaced with nitrogen. In other words, the inside of the inner pipe 11 is purged.

[0052] At time t35, the gas nozzle 32 starts supplying ammonia into the inner tube 11. The ammonia is activated by being heated by the container heating unit 50 as it flows through the gas nozzle 32. The activated ammonia nitrides the dichlorosilane and ethylene adsorbed on the surface of each substrate W.

[0053] At time t36, the gas nozzle 32 stops supplying ammonia into the inner pipe 11. During the period from time t36 to time t37, the gas nozzle 31 continues to supply nitrogen into the inner pipe 11. As a result, the ammonia remaining in the inner pipe 11 is replaced with nitrogen. In other words, the inside of the inner pipe 11 is purged.

[0054] At time t37, the gas nozzle 32 starts supplying ozone into the inner tube 11. The ozone is activated by being heated by the container heating unit 50 as it flows through the gas nozzle 32. The activated ozone oxidizes the dichlorosilane and ethylene adsorbed on the surface of each substrate W.

[0055] At time t38, the gas nozzle 32 stops supplying ozone into the inner pipe 11. From time t38 to time t39, the gas nozzle 31 continues to supply nitrogen into the inner pipe 11. As a result, the ozone remaining in the inner pipe 11 is replaced with nitrogen. In other words, the inside of the inner pipe 11 is purged.

[0056] Next, the process from time t31 to time t39 is defined as an ALD cycle, and the ALD cycle is repeated multiple times, thereby forming an SiOCN film on the surface of each of the substrates W held in the boat 16.

[0057] Next, the control unit 90 increases the pressure inside the processing vessel 10 to atmospheric pressure, and decreases the temperature inside the processing vessel 10 to the unloading temperature, and then lowers the arm 25A to unload the boat 16 from the processing vessel 10. This completes the film formation process on the multiple substrates W.

[0058] According to the film formation method of the third example, dichlorosilane and ethylene are activated in the gas nozzle 31 by heating with the gas heating unit, and the activated dichlorosilane and ethylene are supplied into the inner tube 11. This improves the reactivity of dichlorosilane and ethylene. As a result, the film formation rate can be improved when forming an SiOCN film at a low temperature. Furthermore, since the dichlorosilane and ethylene in the gas nozzle 31 can be heated by a gas heating unit provided separately from the container heating unit 50, the set temperature of the container heating unit 50 can be lowered. This reduces the thermal history that the substrate W processed in the inner tube 11 is subjected to. Thus, according to the film formation method of the third example, it is possible to achieve both a reduction in the thermal history and an improvement in the reactivity of dichlorosilane and ethylene.

[0059] 6, the gas nozzle 31 is heated by the gas heater from time t31 until the film formation process is completed, but the timing at which the gas heater heats the gas nozzle 31 is not limited to this. For example, the gas heater may heat the gas nozzle 31 at the same time that the gas nozzle 31 supplies dichlorosilane and ethylene into the inner tube 11. That is, the gas heater may heat the gas nozzle 31 from time t31 to time t32 and from time t33 to time t34. For example, the gas heater may start heating the gas nozzle 31 before time t31.

[0060] 6, a method for forming an SiOCN film has been described, but a SiON film and a SiCN film can also be formed in the same manner. For example, a SiON film can be formed by atomic layer deposition in which dichlorosilane, ammonia, and ozone are supplied asynchronously. For example, a SiCN film can be formed by atomic layer deposition in which dichlorosilane, ethylene, and ammonia are supplied asynchronously.

[0061] [Experimental results] (Experiment 1) In experiment 1, a silicon nitride film was formed by performing the film formation method shown in the timing chart of Figure 4 in the film formation apparatus 1 according to the embodiment under conditions 1A and 1B shown below, and the thickness of the silicon nitride film was measured.

[0062] <Condition 1A> Dichlorosilane supply time (time from time t11 to time t12): 10 seconds Number of ALD cycles: 200 Set temperature of container heating section 50: 550℃ Gas heating unit temperature setting: 800℃

[0063] <Condition 1B> Dichlorosilane supply time: 30 seconds Number of ALD cycles: 100 Set temperature of container heating section 50: 550℃ Gas heating unit temperature setting: 800℃

[0064] For comparison, in addition to Condition 1A and Condition 1B, silicon nitride films were formed under conditions where the gas nozzle 31 was not heated by the gas heating unit (hereinafter referred to as "Condition 1X" and "Condition 1Y"), and the thicknesses of the silicon nitride films were measured.

[0065] <Condition 1X> Dichlorosilane supply time: 10 seconds Number of ALD cycles: 200 Set temperature of container heating section 50: 550℃ Gas heating unit: OFF

[0066] <Condition 1Y> Dichlorosilane supply time: 30 seconds Number of ALD cycles: 100 Set temperature of container heating section 50: 550℃ Gas heating unit: OFF

[0067] 7 is a diagram showing the measurement results of the thickness of the silicon nitride film, which shows the thicknesses [Å] of the silicon nitride film under conditions 1X, 1A, 1Y, and 1B, from the left.

[0068] As shown in Figure 7, the thickness of the silicon nitride film under condition 1X was 11 Å, while the thickness of the silicon nitride film under condition 1A was 50 Å. As shown in Figure 7, the thickness of the silicon nitride film under condition 1Y was 9 Å, while the thickness of the silicon nitride film under condition 1B was 43 Å. These results demonstrate that the use of dichlorosilane heated in gas nozzle 31 by the gas heater improves the film formation rate when forming a silicon nitride film.

[0069] (Experiment 2) In Experiment 2, a silicon nitride film was formed by performing the film formation method shown in the timing chart of FIG. 4 under Condition 2A shown below in the film formation apparatus 1 according to the embodiment, and the film formation rate (GPC: Growth Per Cycle) of the silicon nitride film was determined.

[0070] <Condition 2A> Dichlorosilane supply time: 10 seconds Number of ALD cycles: 200 Container heating section 50 setting temperature: 400℃~650℃ Gas heating unit temperature setting: 800℃

[0071] For comparison, a silicon nitride film was formed under conditions other than condition 2A, except that the gas nozzle 31 was not heated by the gas heater (hereinafter referred to as "condition 2X"), and the film formation rate of the silicon nitride film was determined.

[0072] <Condition 2X> Dichlorosilane supply time: 10 seconds Number of ALD cycles: 200 Container heating section 50 setting temperature: 400℃~650℃ Gas heating unit: OFF

[0073] Fig. 8 shows the measurement results of the deposition rate of the silicon nitride film. In Fig. 8, the horizontal axis represents the set temperature [°C] of the container heating unit 50, and the vertical axis represents the deposition rate [Å / cycle] of the silicon nitride film. In Fig. 8, circles represent the results under condition 2A, and triangles represent the results under condition 2X.

[0074] 8, it can be seen that the deposition rate of the silicon nitride film when the set temperature of the container heating unit 50 is 500°C under condition 2A is approximately the same as the thickness of the silicon nitride film when the set temperature of the container heating unit 50 is 550°C under condition 2X. This result shows that by using dichlorosilane heated in the gas nozzle 31 by the gas heating unit, a silicon nitride film can be formed at a lower temperature and at approximately the same deposition rate as when dichlorosilane not heated in the gas nozzle 31 is used.

[0075] (Experiment 3) In Experiment 3, a silicon nitride film was formed by performing the film formation method shown in the timing chart of Fig. 4 under Condition 3A shown below in the film formation apparatus 1 according to the embodiment, and the etching resistance and stress of the silicon nitride film were evaluated. The etching resistance was measured using the wet etching rate (WER) when the silicon nitride film was wet etched with diluted hydrofluoric acid at a concentration of 0.25%.

[0076] <Condition 3A> Dichlorosilane supply time: 10 seconds to 60 seconds Number of ALD cycles: 200 Set temperature of container heating section 50: 550℃ Gas heating unit temperature setting: 800℃

[0077] For comparison, a silicon nitride film was formed by plasma ALD (hereinafter referred to as "Condition 3X"), in which the supply of dichlorosilane and the supply of plasma generated by exciting ammonia gas with RF (Radio Frequency) power were alternately performed. The etching resistance and stress of the silicon nitride film were also evaluated.

[0078] <Condition 3X> Set temperature of container heating section 50: 550℃

[0079] Fig. 9 shows the measurement results of the WER of the silicon nitride film. In Fig. 9, the four graphs on the left show the WER [Å / min] under condition 3A, and the one graph on the right shows the WER [Å / sec] under condition 3X.

[0080] 9, comparing the four graphs under condition 3A with the single graph under condition 3X reveals that the WER is approximately the same. This result indicates that forming a silicon nitride film using dichlorosilane heated in the gas nozzle 31 by the gas heater can achieve approximately the same WER as forming a silicon nitride film by plasma ALD.

[0081] Fig. 10 shows the results of measuring the stress of the silicon nitride film. In Fig. 10, the two graphs on the left show the stress [MPa] of the silicon nitride film under condition 3A, and the graph on the right shows the stress [MPa] of the silicon nitride film under condition 3X.

[0082] 10, it can be seen that the stress of the silicon nitride film under condition 3A is about 300 MPa, while the stress of the silicon nitride film under condition 3X is about 850 MPa. This result shows that by forming a silicon nitride film using dichlorosilane heated in the gas nozzle 31 by the gas heater, the stress of the silicon nitride film can be reduced compared to when the silicon nitride film is formed by plasma ALD.

[0083] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0084] In the above embodiment, the first source gas is dichlorosilane, but the present disclosure is not limited thereto. The first source gas is, for example, a silicon-containing gas. The silicon-containing gas is, for example, aminosilane, silicon hydride, or halogen-containing silicon. The aminosilane may be diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), bis(tert-butylaminosilane) (BTBAS), or a combination thereof. The silicon hydride may be monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), tetrasilane (Si4H 10 The halogen-containing silicon may be a fluorine-containing silicon such as SiF, SiHF, SiH, F, or SiH, a chlorine-containing silicon such as SiCl, SiHCl, SiH, Cl, SiH, Cl, or SiCl, a bromine-containing silicon such as SiBr, SiHBr, SiH, Br, or SiHBr, or a combination thereof.

[0085] In the above embodiment, the second source gas is ethylene, but the present disclosure is not limited thereto. The second source gas is, for example, a carbon-containing gas. The carbon-containing gas is, for example, a hydrocarbon. The hydrocarbon may be ethylene (C2H4), methane (CH4), ethane (C2H6), propane (C3H8), propylene (C3H6), acetylene (C2H2), or a combination thereof.

[0086] In the above embodiment, the first reactive gas is ammonia, but the present disclosure is not limited thereto. The first reactive gas is a gas that reacts with the first source gas to produce a reaction product. The first reactive gas is, for example, a nitriding gas. The nitriding gas may be ammonia, diazene (NH), hydrazine (NH), monomethylhydrazine (CH(NH)NH), or a combination thereof.

[0087] In the above embodiment, the second reactant gas is ozone, but the present disclosure is not limited thereto. The second reactant gas is a gas that reacts with the first source gas to produce a reaction product. The second reactant gas is, for example, an oxidizing gas. The oxidizing gas may be ozone, oxygen (O), water vapor (H), nitrogen dioxide (NO), or a combination thereof. [Explanation of symbols]

[0088] 1 Film deposition equipment 10 Processing container 31 Gas nozzle 32 Gas nozzle 50 Container heating section 201 Alumina Core 202 Heating element W substrate

Claims

1. Loading a plurality of substrates into a processing chamber; heating the inside of the processing vessel by a vessel heating unit provided around the processing vessel; heating a first source gas in a first gas nozzle by a gas heating unit of the first gas nozzle, and supplying the heated first source gas from the first gas nozzle into the processing vessel; supplying a first reactive gas that reacts with the first source gas into the processing vessel through a second gas nozzle; repeating a cycle including supplying the first source gas and supplying the first reactant gas a plurality of times; The film forming method includes the steps of:

2. The set temperature of the gas heating unit is higher than the set temperature of the container heating unit. The film forming method according to claim 1 .

3. The first reactive gas is activated by heating. The film forming method according to claim 1 .

4. the first source gas is a silicon-containing gas, The first reactive gas is a nitriding gas or an oxidizing gas. The film forming method according to claim 1 .

5. the gas heater heats a second source gas in the first gas nozzle, and the second source gas is supplied from the first gas nozzle into the processing vessel; the cycle further includes supplying the second source gas. The film forming method according to claim 1 .

6. the first source gas is a silicon-containing gas, the second source gas is a carbon-containing gas, The first reactive gas is a nitriding gas or an oxidizing gas. The film forming method according to claim 5 .

7. supplying a second reactive gas that reacts with the first source gas into the processing chamber through the second gas nozzle; the cycle further includes supplying the second reactant gas. The film forming method according to claim 1 .

8. the first source gas is a silicon-containing gas, the first reactive gas is a nitriding gas; the second reactive gas is an oxidizing gas; The film forming method according to claim 7 .

9. a processing vessel for accommodating a plurality of substrates; a container heating unit provided around the processing container and configured to heat the inside of the processing container; a first gas nozzle that supplies a first source gas into the processing vessel; a second gas nozzle configured to supply a first reactive gas that reacts with the first source gas into the processing chamber; A control unit; Equipped with the first gas nozzle has a gas heating unit that heats the first source gas inside the first gas nozzle, The control unit Loading a plurality of the substrates into the processing chamber; the container heating unit heats the inside of the processing container; the gas heating unit heats the first source gas in the first gas nozzle, and the first gas nozzle supplies the heated first source gas into the processing vessel; the second gas nozzle supplies the first reaction gas into the processing chamber; repeating a cycle including supplying the first source gas and supplying the first reactant gas a plurality of times; configured to perform Film deposition equipment.

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