Film forming device, film forming method, and substrate processing method

Abstract

This film forming device has a support part, a processing container, a gas supply unit, and a control unit. The support part is configured to be able to support the substrate and adjust the temperature of the substrate. The processing container is provided with the support part inside and is configured to be able to generate plasma. The gas supply unit is configured to be able to supply oxygen and a precursor of any one of Mg, Ge, B, Al, and Sc containing hydrogen or hydrocarbon to the processing container. The control unit performs control to control the temperature of the substrate to 300°C or less by means of the support unit, generate plasma in the processing container while supplying oxygen and the precursor into the processing container from the gas supply unit, and form a film containing any one of Mg, Ge, B, Al, and Sc on the substrate.

Description

Film forming apparatus, film forming method, and substrate processing method

[0001] Various aspects and embodiments of the present disclosure relate to a film deposition apparatus, a film deposition method, and a substrate processing method.

[0002] Patent Document 1 listed below discloses a substrate processing apparatus comprising: "a mixing section that mixes primary phosphoric acid and an additive, which are raw materials for a processing liquid, at a predetermined mixing ratio to prepare a mixed liquid; a mixing ratio correction section that corrects the mixing ratio of the raw materials for the processing liquid; and a processing section that processes a substrate with the processing liquid, wherein the mixing section includes a mixing tank that stores the mixed liquid, a primary phosphoric acid supply section that supplies the primary phosphoric acid to the mixing tank, and an additive supply section that supplies the additive to the mixing tank, and the mixing ratio correction section includes a liquid transfer line that transfers the mixed liquid from the mixing section to the processing section, and a secondary phosphoric acid supply section that supplies secondary phosphoric acid midway along the liquid transfer line."

[0003] Japanese Patent Application Laid-Open No. 2020-167308

[0004] The present disclosure provides a film forming apparatus, a film forming method, and a substrate processing method that are capable of forming a film that is removable with water.

[0005] A film formation apparatus according to one aspect of the present disclosure includes a support unit, a processing vessel, a gas supply unit, and a control unit. The support unit is configured to support a substrate and adjust the temperature of the substrate. The processing vessel has the support unit installed therein and is configured to generate plasma. The gas supply unit is configured to supply oxygen and a precursor containing hydrogen or a hydrocarbon, selected from Mg, Ge, B, Al, and Sc, to the processing vessel. The control unit controls the temperature of the substrate to 300°C or less using the support unit, and generates plasma in the processing vessel while supplying oxygen and the precursor from the gas supply unit into the processing vessel, thereby forming a film containing Mg, Ge, B, Al, or Sc on the substrate.

[0006] According to the present disclosure, a film that can be removed with water can be formed.

[0007] FIG. 1 is a diagram illustrating an example of a film forming apparatus according to an embodiment. FIG. 2 is a flowchart illustrating an example of the flow of a film forming process according to an embodiment. FIG. 3 is a diagram illustrating an example of a substrate processing apparatus according to an embodiment. FIG. 4 is a diagram illustrating an example of the result of removing a film from a substrate W with water according to an embodiment. FIG. 5A is a diagram illustrating an example of an etching result according to an embodiment. FIG. 5B is a diagram illustrating an example of an etching result according to an embodiment. FIG. 6 is a diagram illustrating an example of a manufacturing process of a semiconductor device according to a comparative example. FIG. 7 is a diagram illustrating an example of a manufacturing process of a semiconductor device according to an embodiment.

[0008] Hereinafter, embodiments of a film forming apparatus, a film forming method, and a substrate processing method disclosed herein will be described in detail with reference to the drawings. Note that the disclosed film forming apparatus, film forming method, and substrate processing method are not limited to the embodiments.

[0009] In the manufacture of semiconductor devices, carbon-based hard masks such as amorphous carbon (ACL) are used as masks, and SiN (silicon nitride)-based films are used as sacrificial films from the viewpoint of removal performance, etc.

[0010] When a carbon-based hard mask or a SiN-based film is removed, damage to the remaining film may occur. For example, a carbon-based hard mask is removed by ashing, but the heat of the ashing may damage the remaining film. Also, a SiN-based film is removed by immersing it in a solution containing phosphoric acid, but the phosphoric acid may damage the remaining film.

[0011] Therefore, it is preferable that the mask and the sacrificial film are removable with water. Therefore, a technique for forming a film that is removable with water is provided.

[0012] (Embodiment) (Configuration of Film Forming Apparatus) An embodiment will be described. First, an example of a film forming apparatus according to an embodiment will be described. Fig. 1 is a diagram showing an example of a film forming apparatus 100 according to an embodiment.

[0013] The film forming apparatus 100 includes a substantially cylindrical chamber 101. The chamber 101 is made of, for example, aluminum whose inner wall surface has been subjected to OGF (Out Gas Free) anodizing treatment. In the embodiment, the chamber 101 corresponds to a processing vessel of the present disclosure.

[0014] A support 102 for horizontally supporting a substrate W such as a semiconductor wafer is provided inside the chamber 101. The support 102 is supported by a cylindrical support member 103 provided at the lower center. An opening is formed at the center of the bottom of the chamber 101. A cylindrical protrusion 101b is connected to the lower portion of the opening. The support member 103 is supported by the protrusion 101b.

[0015] The support part 102 has a main body made of aluminum, for example, and an insulating ring (not shown) provided around its periphery. The support part 102 is provided therein with a temperature adjustment mechanism 104 for adjusting the temperature of the substrate W placed thereon. The temperature adjustment mechanism 104 is, for example, a heater or a flow path formed in the support part 102. The temperature adjustment mechanism 104 can adjust the temperature of the substrate W by supplying power to the heater to cause the heater to generate heat, or by passing a temperature-controlled temperature adjustment medium through the flow path.

[0016] The support part 102 has three lifting pins (not shown) for transporting the substrate W that are provided so as to be protruding and retracting from the surface of the support part 102. An electrostatic chuck for electrostatically attracting the substrate W may be provided on the upper surface of the support part 102.

[0017] A shower head 105 is provided on the upper part of the support part 102. In one embodiment, the shower head 105 forms at least a part of the ceiling of the chamber 101. The shower head 105 has a shower plate 106 provided directly below the ceiling wall 101a of the chamber 101. The shower plate 106 is disk-shaped and has a large number of gas ejection holes 107 formed therein. The shower plate 106 has a main body made of, for example, aluminum, on the surface of which a thermal spray coating made of yttria is formed. The shower plate 106 is insulated from the chamber 101 by a ring-shaped insulating member 106a.

[0018] A gas inlet 108 is provided in the center of a ceiling wall 101a of the chamber 101. A gas diffusion space 109 is formed between the ceiling wall 101a and the shower plate 106. A gas pipe 110a is connected to the gas inlet 108. The gas pipe 110a is connected to a gas supply mechanism 110.

[0019] The gas supply mechanism 110 has gas supply sources for various gases used in film formation and a plurality of gas supply pipes for supplying each gas from the plurality of gas supply sources. Each gas supply pipe in the gas supply mechanism 110 is provided with an on-off valve and a flow rate controller such as a mass flow controller (neither of which is shown), which enable gas switching and gas flow rate control.

[0020] The gas supply mechanism 110 supplies various gases used in film formation to a gas pipe 110a. The gas supplied to the gas pipe 110a is supplied to the shower head 105 from a gas inlet 108. The gas supplied to the shower head 105 is diffused in a gas diffusion space 109 and discharged into the chamber 101 from gas discharge holes 107 of a shower plate 106.

[0021] A first high frequency power supply 113 is connected to the shower plate 106 via a matching box 114. High frequency power is applied to the shower plate 106 from the first high frequency power supply 113. The shower plate 106 functions as an upper electrode, and the support portion 102 functions as a lower electrode, with the shower plate 106 and the support portion 102 constituting a pair of parallel plate electrodes. When high frequency power is applied to the shower plate 106, capacitively coupled plasma is generated within the chamber 101. The frequency of the high frequency power output from the first high frequency power supply 113 is preferably set to 400 kHz to 13.56 MHz, and for example, 13.56 MHz is used.

[0022] On the other hand, a second high frequency power supply 115 is connected to the supporting part 102 via a matching box 116. A high frequency bias power is applied to the supporting part 102 from the second high frequency power supply 115. By applying the high frequency bias power to the supporting part 102, ions in the plasma generated in the chamber 101 are attracted to the substrate W.

[0023] Exhaust ports 121 and 122 are provided at the bottom of the chamber 101. An exhaust mechanism 120 is connected to the exhaust ports 121 and 122. The exhaust mechanism 120 has a first exhaust pipe 123, a second exhaust pipe 124, a first pressure control valve 125, a dry pump (DRP) 126, a second pressure control valve 127, and a turbo pump (TMP) 128. The first exhaust pipe 123 is connected to the exhaust port 121. The second exhaust pipe 124 is connected to the exhaust port 122. The first exhaust pipe 123 is provided with the first pressure control valve 125 and the dry pump 126. The second exhaust pipe 124 is provided with the second pressure control valve 127 and the turbo pump 128. During a film formation process in which the inside of the chamber 101 is set to a high pressure, the chamber 101 is evacuated only by the dry pump 126. During plasma processing in which the pressure inside the chamber 101 is set to a low pressure, a dry pump 126 and a turbo pump 128 are used in combination. The pressure inside the chamber 101 is controlled by controlling the openings of a first pressure control valve 125 and a second pressure control valve 127 based on the detection value of a pressure sensor (not shown) provided in the chamber 101.

[0024] A side wall of the chamber 101 is provided with a transfer port 130 for transferring the substrate W between the chamber 101 and a vacuum transfer chamber (not shown) connected to the chamber 101, and a gate valve G for opening and closing the transfer port 130. The substrate W is transferred by a transfer mechanism (not shown) provided in the vacuum transfer chamber.

[0025] The film forming apparatus 100 includes a control unit 140. The control unit 140 includes a main control unit, an input device (such as a keyboard or a mouse), an output device (such as a printer), a display device (such as a display), and a storage device (storage medium). The main control unit includes a CPU (computer) and controls each component of the film forming apparatus 100. For example, the main control unit controls the valves and mass flow controllers of the gas supply mechanism 110, the first high-frequency power supply 113, the second high-frequency power supply 115, the exhaust mechanism 120, the temperature adjustment mechanism 104, the transfer mechanism, the gate valve G, and the like. The main control unit of the control unit 140 causes the film forming apparatus 100 to perform various processes, including the film forming process described below, based on, for example, a process recipe stored in a storage medium built into the storage device or a storage medium set in the storage device.

[0026] (Film formation process flow) Next, an example of a flow of performing a film formation process including the film formation method of the present disclosure using the film formation apparatus 100 configured as described above will be described. Fig. 2 is a flowchart showing an example of a flow of a film formation process according to an embodiment. The film formation process is performed based on the control of the control unit 140.

[0027] In step S10, the substrate W is placed on the support part 102 of the film forming apparatus 100. For example, the substrate W is transferred into the chamber 101 through the transfer port 130 by a transfer mechanism of a vacuum transfer chamber connected to the chamber 101, and placed on the support part 102.

[0028] Next, in step S11, the temperature of the substrate W is controlled to 300°C or less. The temperature of the support part 102 can be adjusted by the temperature adjustment mechanism 104. The control part 140 controls the temperature of the substrate W to 300°C or less by adjusting the temperature of the temperature adjustment mechanism 104. The temperature of the substrate W is preferably in the range of 50-300°C, and more preferably in the range of 50-200°C.

[0029] Next, in step S12, oxygen and a precursor containing hydrogen or a hydrocarbon, selected from Mg (magnesium), Ge (germanium), B (boron), Al (aluminum), and Sc (scandium), are supplied from the gas supply mechanism 110 into the chamber 101. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and the precursor from the gas supply mechanism 110 into the chamber 101. Then, in step S12, plasma is generated in the chamber 101 in accordance with the supply of the precursor, and a film containing any of Mg, Ge, B, Al, and Sc is formed on the substrate W. For example, the control unit 140 controls the first high-frequency power supply 113 and the second high-frequency power supply 115 to supply high-frequency power from the first high-frequency power supply 113 and the second high-frequency power supply 115, respectively, to generate plasma in the chamber 101 and form a film containing any of Mg, Ge, B, Al, and Sc on the substrate W. For example, when a film containing Mg is to be formed, oxygen and a Mg precursor containing hydrogen or a hydrocarbon are supplied from the gas supply mechanism 110 into the chamber 101. As a result, an MgO film is formed on the substrate W as a film containing Mg. Furthermore, when a film containing Ge is to be formed, oxygen and a Ge precursor containing hydrogen or a hydrocarbon are supplied from the gas supply mechanism 110 into the chamber 101. As a result, a GeO film is formed on the substrate W as a film containing Ge. Furthermore, when a film containing Mg and Ge is to be formed, oxygen and a Mg and Ge precursor containing hydrogen or a hydrocarbon are supplied from the gas supply mechanism 110 into the chamber 101. As a result, an MgGeO film is formed on the substrate W as a film containing Mg and Ge.

[0030] The precursor of Mg is, for example, an organic material containing Mg. Examples of the precursor of Mg include DETMg (diethoxymagnesium) and TEMg (triethylmagnesium). The precursor of Ge is, for example, an organic material containing Ge. Examples of the precursor of Ge include TMGe (trimethylgermanium) and TETGe (tetraethyltetraethoxygermanium). The precursor of B is, for example, an organic material containing B. Examples of the precursor of B include TMB (trimethylboron) and TDMAB (trisdimethylaminoboron). The precursor of Al is, for example, an organic material containing Al. Examples of the precursor of Al include TMAl (trimethylaluminum) and DMAI (dimethylaluminum isopropoxide). The precursor of Sc is, for example, an organic material containing Sc. An example of a precursor of Sc is TMSMSc (trimethylsilylmethylscandium).

[0031] In the film forming process according to the embodiment, the hydrocarbon contained in the precursor reacts with oxygen to generate a hydroxyl group. ３ and O react with each other, resulting in partial decomposition and the generation of OH. By forming a film on the substrate W at a temperature of 300°C or less, a film containing any of Mg, Ge, B, Al, and Sc that is formed on the substrate W incorporates OH and becomes a film containing hydroxide. The film formed on the substrate W in this manner contains hydroxide, making it removable with water. For example, deionized water or pure water can be used as the water used to remove the film. By setting the temperature of the substrate W in the range of 50-300°C, more preferably in the range of 50-200°C, during the film formation process, the film can contain a large amount of hydroxide, thereby improving the removability with water.

[0032] Here, an example of processing conditions for forming a GeO film will be described.

[0033] (Film formation processing conditions) Dry-Ar: 50 sccm (0.085 m 3 / s) Dil-Ar: 50sccm O ２Gas: 100 sccm TMGe gas: 2.0 sccm Pressure in chamber 101: 400 Pa Temperature of substrate W: 100° C. Dil-Ar is Ar (air) used when supplying the precursor.

[0034] The process conditions for film formation may be adjusted as appropriate depending on the configuration of the film formation apparatus 100 and the substrate W. For example, the process conditions for film formation are preferably process conditions under which a peak appears at a wavenumber corresponding to OH in the infrared light absorbance spectrum for each wavenumber measured by FT-IR (Fourier transform infrared spectroscopy) analysis of the substrate W on which the film has been formed. Furthermore, in order to improve removability with water, the process conditions for film formation are preferably process conditions under which the peak of the wavenumber corresponding to OH is largest in the absorbance spectrum. For example, the process conditions for film formation are preferably process conditions under which the peak of the wavenumber corresponding to OH is largest in the absorbance spectrum.

[0035] (Configuration of Substrate Processing Apparatus) Next, an example of a substrate processing apparatus that uses water to remove a film formed by a film formation process according to an embodiment will be described. In the following, an example will be described in which the substrate processing apparatus is configured as a batch type that can process multiple substrates W simultaneously. Figure 3 is a diagram showing an example of a substrate processing apparatus 200 according to an embodiment. In Figure 3, the vertical direction is shown as the Z-axis direction, and two orthogonal horizontal axes are shown as the X-axis direction and the Y-axis direction.

[0036] The substrate processing apparatus 200 includes a processing tank 211. The processing tank 211 is, for example, a double tank, and includes an inner tank 211a and an outer tank 211b. The inner tank 211a stores the etching solution L1. The outer tank 211b recovers the etching solution L1 that overflows from the inner tank 211a. In the embodiment, the inner tank 211a corresponds to a container of the present disclosure.

[0037] The substrate processing apparatus 200 includes a circulation path 212. The circulation path 212 sends the etching solution L1 taken out from the outer bath 211b to the inner bath 211a. The substrate processing apparatus 200 also includes a pump 213, a heater 214, and a filter 215 along the circulation path 212.

[0038] The pump 213 forms a circulating flow of the etching liquid L1 that is sent from the outer bath 211b to the inner bath 211a via the circulation path 212. The etching liquid L1 also overflows from an opening of the inner bath 211a and flows back into the outer bath 211b. In this way, a circulating flow of the etching liquid L1 is formed in the substrate processing apparatus 200. That is, the circulating flow is formed in the outer bath 211b, the circulation path 212, and the inner bath 211a.

[0039] The heater 214 adjusts the temperature of the etching liquid L1 circulating through the circulation path 212. The filter 215 collects particles contained in the etching liquid L1 circulating through the circulation path 212 and filters the etching liquid L1.

[0040] The substrate processing apparatus 200 also has a horizontal pipe 216 inside the inner tank 211a. The horizontal pipe 216 supplies the etching liquid L1 sent from the circulation path 212 into the inner tank 211a. The horizontal pipe 216 extends in the Y-axis direction, and a plurality of the horizontal pipes 216 are provided at intervals in the X-axis direction.

[0041] The horizontal pipes 216 each have a plurality of discharge ports (not shown) spaced apart in the longitudinal direction, and each of the discharge ports discharges the etching solution L1 directly upward, thereby forming a curtain-like upward flow in the inner tank 211 a.

[0042] The substrate processing apparatus 200 also has a substrate holding unit 217. The substrate holding unit 217 moves up and down between a standby position and a processing position while holding multiple substrates W at intervals in the Y-axis direction. The standby position is a position where the multiple substrates W are transferred to and from a transport device (not shown), and is set above the processing position. The processing position is a position where the multiple substrates W are immersed in the etching solution L1.

[0043] The substrate holder 217 receives the unprocessed substrate W from the transport device at the standby position, then descends to the processing position, and after a predetermined time has elapsed, ascends again to the standby position and hands over the processed substrate W to the transport device at the standby position.

[0044] The substrate processing apparatus 200 includes a liquid supply unit 218 and a liquid drainage unit 219 .

[0045] When removing films formed on a plurality of substrates W, the liquid supply unit 218 supplies the etching liquid L1 to the processing tank 211. The substrate processing apparatus 200 according to the embodiment supplies water as the etching liquid L1 to the processing tank 211. The water may be, for example, deionized water or pure water.

[0046] The treatment tank 211 stores water supplied as the etching liquid L1 from a liquid supply unit 218. A plurality of substrates W are immersed in the water inside the treatment tank 211. The temperature of the water in the treatment tank 211 is adjusted by a heater 214 to a temperature suitable for removing the film.

[0047] The drainage part 219 is provided at the bottom of the inner tank 211a. The etching solution L1 stored in the processing tank 211 is discharged from the drainage part 219 as needed. The drainage part 219 may be provided in the circulation path 212.

[0048] (Evaluation Results) Next, specific evaluation results of films formed by the film formation process according to the embodiment will be described. First, an example of the removal results of films containing any of Mg, Ge, B, Al, and Sc formed on a substrate W using the film formation process according to the embodiment, including an MgO film, an MgGeO film, a GeO film, a BO film, an AlO film, and an ScO film, will be described. The MgGeO film was formed by alternately depositing MgO and GeO films with a thickness ratio or a material ratio of Mg to Ge of 1:1. Deionized water (DIW) was used as the water used for removal. FIG. 4 shows an example of the removal results according to the embodiment. DIW@RT indicates the case where the substrate W was immersed in water (deionized water) at room temperature (RT). Room temperature refers to a standard room temperature, e.g., 10 to 30°C. DIW@100° C. indicates the case where the substrate W is immersed in water (deionized water) at 100° C.

[0049] The removal rate of an MgO film is as low as 0.1 nm / min when using water at room temperature, but increases to 10 nm / min when using water at 100°C. The removal rate of an MgGeO film is 50 nm / min when using water at room temperature, but increases to more than 100 nm / min when using water at 100°C. The removal rate of an AlO film is 5 nm / min when using water at room temperature, but increases to 20 nm / min when using water at 100°C. The removal rates of a GeO film and a BO film are greater than 1000 nm / min even when using water at room temperature. The removal rate of a film containing any of Mg, Ge, B, and Al formed by the film formation process according to the embodiment increases as the water temperature increases. High-temperature water under pressure may also be used to remove the film. For example, the film may be removed by placing the substrate W in a pressurized container and exposing the substrate W to water vapor at 100° C. or higher.

[0050] In this way, the film containing any of Mg, Ge, B, and Al formed by the film formation process according to the embodiment can be removed with water.

[0051] Next, an example of an etching result obtained by forming an MgO film, a GeO film, a BO film, and an AlO film on a substrate W as a film containing any of Mg, Ge, B, and Al by the film forming process according to the embodiment, and then performing plasma etching on each substrate W will be described. Figures 5A and 5B are diagrams showing an example of an etching result according to the embodiment. Figures 5A and 5B show the etching results of the MgO film, the GeO film, the BO film, and the AlO film, using CF ４ Gas, C ４ F ８ Gas, NF ３5A shows the results of plasma etching using a gas as an etching gas. FIG. 5A shows the selectivity ratios of an MgO film, a GeO film, a BO film, and an AlO film relative to an SiO film when a SiO (silicon oxide) film is similarly plasma etched. The larger the selectivity ratio in FIG. 5A, the more difficult it is to etch compared to an SiO film. FIG. 5B shows the selectivity ratios of an MgO film, a GeO film, a BO film, and an AlO film relative to an SiN film when a SiN film is similarly plasma etched. The larger the selectivity ratio in FIG. 5B, the more difficult it is to etch compared to an SiN film.

[0052] As shown in FIG. 5A, the MgO film is ４ Gas, C ４ F ８ Gas, NF ３ The selectivity value is greater than 1 for any of the gases. Therefore, the MgO film is less likely to be etched than the SiO film. In particular, the MgO film is more likely to be etched when the etching gas is CF ４ Gas, NF ３ In the case of the etching gas, the selectivity value is much larger than 1. Therefore, the MgO film is ４ Gas, NF ３ In the case of CF 3 gas, the selectivity to the SiO film is high. ４ Gas, C ４ F ８ Gas, NF ３ The selectivity values ​​for all of the gases are smaller than 1. Therefore, the GeO film and the BO film are more easily removed than the SiO film. ４ In the case of gases, the selectivity value is significantly greater than 1. ４ F ８ Gas, NF ３ In the case of CF gas, the selectivity is smaller than 1. Therefore, the AlO film is ４ In the case of gas, it is more difficult to remove than SiO film, and C ４ F ８ Gas, NF ３ In the case of gas, it is easier to scrape than the SiO film.

[0053] As shown in FIG. 5B, the MgO film is ４ Gas, C ４F ８ Gas, NF ３ The selectivity value is greater than 1 for any of the gases. Therefore, the MgO film is less likely to be etched than the SiN film. In particular, the MgO film is more easily etched when the etching gas is CF ４ Gas, NF ３ For this reason, the etching gas for the MgO film is CF ４ Gas, NF ３ In the case of CF 2 O 4 gas, the selectivity to the SiN film is high. ４ Gas, C ４ F ８ Gas, NF ３ The selectivity values ​​for all of the gases are smaller than 1. Therefore, the GeO film and the BO film are more easily removed than the SiN film. ４ In the case of gas, the selectivity is greater than 1, and C ４ F ８ Gas, NF ３ In the case of CF gas, the selectivity is smaller than 1. Therefore, the AlO film is ４ In the case of gas, it is more difficult to remove than the SiN film, and ４ F ８ Gas, NF ３ In the case of gas, it is easier to etch than the SiN film.

[0054] Therefore, the MgO film is CF ４ Gas, C ４ F ８ Gas, NF ３ The gas can be used as a mask when plasma etching an SiO film or an SiN film using the gas as an etching gas. In particular, the etching gas is CF ４ Gas, NF ３ In the case of gas, if the mask is an MgO film, the mask can be made thin because of its high selectivity. ４ The gas can be used as a mask when plasma etching an SiO film or an SiN film is performed using the gas as an etching gas.

[0055] Furthermore, a film containing any of Mg, Ge, B, Al, and Sc formed by the film formation process according to the embodiment can be removed with water, and therefore can also be used as a sacrificial film.

[0056] Next, an example of a manufacturing process of a semiconductor device using a film formed by the film formation process according to the embodiment will be described. In the following, a case where the semiconductor device is applied to a manufacturing process of a 3D-NAND flash memory will be described as an example.

[0057] First, as a comparative example, an example of a conventional semiconductor device manufacturing process will be described. FIG. 6 is a diagram illustrating an example of a semiconductor device manufacturing process according to the comparative example. FIGS. 6A-6E show a portion of a manufacturing process of a 3D-NAND flash memory. As shown in FIG. 6A, a stacked body 12 is formed on a substrate W, in which SiO films 10 and SiN films 11 serving as sacrificial films are alternately stacked. In the manufacturing of conventional semiconductor devices, SiN films are used as sacrificial films from the viewpoint of removal performance, etc. A hard mask 13 made of amorphous carbon (ACL) is formed on the stacked body 12. In the manufacturing process of the semiconductor device according to the comparative example, a pattern is formed on the hard mask 13 by a lithography process, as shown in FIG. 6B, and then, as shown in FIG. 6C, anisotropic plasma etching is performed on the stacked body 12 using the hard mask 13 as a mask. The etching gas for the anisotropic plasma etching may be, for example, CF ４ Gas, C ４ F ８ Gas, NF ３ Gases, etc., are used. The ACL hard mask 13 has a selectivity ratio of about 2 relative to the SiO film 10 and the SiN film 11. Therefore, in the manufacturing process of the semiconductor device according to the comparative example, the hard mask 13 had to be thickened in order to etch the stack 12. As memory capacity increases, the number of stacked layers also increases, and the thickness required for the hard mask also tends to increase. After etching the stack 12, in the manufacturing process of the semiconductor device according to the comparative example, the ACL hard mask 13 is removed by ashing, as shown in FIG. 6(D). After removing the hard mask 13, in the manufacturing process of the semiconductor device according to the comparative example, the substrate W is immersed in a solution containing phosphoric acid to side-etch each SiN film 11 of the stack 12, as shown in FIG. 6(E). However, each SiO film 10 of the stack 12 is also damaged by phosphoric acid.

[0058] Therefore, by applying the present disclosure, the SiN films 11 of the stack 12 are changed to, for example, GeO films. Furthermore, the hard mask 13 formed by ACL is changed to, for example, an MgO film or an MgGeO film. The GeO film, MgO film, and MgGeO film are formed by a film formation process according to an embodiment. FIG. 7 is a diagram illustrating an example of a manufacturing process for a semiconductor device according to an embodiment. FIGS. 7A-7D show a portion of a manufacturing process for a 3D-NAND flash memory. As shown in FIG. 7A, a stack 22 is formed on a substrate W, in which SiO films 10 and GeO films 21 serving as sacrificial films are alternately stacked. A mask 23 made of an MgO film or an MgGeO film is formed on the stack 22. The GeO film 21 and the MgO film or MgGeO film of the mask 23 are each formed by a film formation process according to an embodiment. As a result, the GeO film 21 and the MgO or MgGeO film of the mask 23 contain OH, and can be removed with water. ４ Gas, C ４ F ８ Gas, NF ３The mask 23 can be used as a mask when anisotropically plasma etching SiO and GeO films using a gas as an etching gas. As shown in FIG. 5A, the MgO film has a high selectivity relative to the SiO film. Furthermore, as shown in FIG. 5B, the selectivity of the GeO film relative to the SiN film is less than 1. That is, the GeO film is more easily etched than the SiN film before the change. Therefore, when the mask 23 is an MgO film, the mask 23 can be made thinner than the hard mask 13 of the comparative example. In the manufacturing process of the semiconductor device according to the embodiment, a pattern is formed on the mask 23 by a lithography process, as shown in FIG. 7B, and the stack 22 is anisotropically plasma etched using the mask 23 as a mask, as shown in FIG. 7C. After etching the stack 22, in the manufacturing process of the semiconductor device according to the embodiment, the substrate W is immersed in water, which allows for simultaneous removal of the mask 23 and side etching of each GeO film 21 of the stack 22, as shown in FIG. 7D. At this time, it is desirable to completely remove the mask 23, but it is also necessary to side-etch the GeO film 21 by an appropriate amount. When immersing the substrate W in water, the thickness of the mask 23 may be controlled so that the time required for the mask 23 remaining after the anisotropic plasma etching to be completely removed is shorter than the time required for the GeO film 21 to be side-etched by an appropriate amount. In this way, the mask 23 can be completely removed while the GeO film 21 can be side-etched by an appropriate amount. Furthermore, in the manufacturing process of the semiconductor device according to the embodiment, the GeO films 21 of the stack 22 can be side-etched with water, thereby suppressing damage to the SiO films 10 of the stack 22.

[0059] The embodiment has been described above. As described above, the film forming apparatus 100 according to the embodiment includes a support part 102, a chamber 101 (processing vessel), a gas supply mechanism 110 (gas supply part), and a control part 140. The support part 102 is configured to support the substrate W and adjust the temperature of the substrate W. The chamber 101 is provided with the support part 102 therein and is configured to generate plasma. The gas supply mechanism 110 is configured to supply oxygen and any one of Mg, Ge, B, Al, and Sc precursors containing hydrogen or hydrocarbons to the chamber 101. The control part 140 controls the temperature of the substrate W to 300° C. or less using the support part 102, and generates plasma in the chamber 101 while supplying oxygen and the precursor from the gas supply mechanism 110 into the chamber 101, thereby forming a film containing any one of Mg, Ge, B, Al, and Sc on the substrate W. As a result, the film forming apparatus 100 according to the embodiment can form a film that can be removed with water.

[0060] The precursor is an organic material containing Mg. The organic material containing Mg is, for example, triethyl magnesium or diethoxy magnesium. The control unit 140 controls the gas supply mechanism 110 to supply oxygen and the organic material containing Mg into the chamber 101, while generating plasma in the chamber 101, to form a film containing Mg on the substrate W. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and either triethyl magnesium or diethoxy magnesium into the chamber 101, while generating plasma in the chamber 101, to form a film containing Mg on the substrate W. In this way, the film formation apparatus 100 according to the embodiment can form a film containing Mg that is removable with water.

[0061] The precursor is an organic material containing Ge. The organic material containing Ge is, for example, either trimethylgermanium or tetramethylgermanium. The control unit 140 controls the gas supply mechanism 110 to supply oxygen and the organic material containing Ge into the chamber 101, while generating plasma in the chamber 101, to form a film containing Ge on the substrate W. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and either trimethylgermanium or tetramethylgermanium into the chamber 101, while generating plasma in the chamber 101, to form a film containing Ge on the substrate W. As a result, the film formation apparatus 100 according to the embodiment can form a film containing Ge that is removable with water.

[0062] The precursor is an organic material containing B. The organic material containing B is, for example, either trimethyl boron or trisdimethylamino boron. The control unit 140 controls the gas supply mechanism 110 to supply oxygen and the organic material containing B into the chamber 101, while generating plasma in the chamber 101, and depositing a film containing B on the substrate W. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and either trimethyl boron or trisdimethylamino boron into the chamber 101, while generating plasma in the chamber 101, and depositing a film containing B on the substrate W. In this way, the film deposition apparatus 100 according to the embodiment can deposit a film containing B that is removable with water.

[0063] The precursor is an organic material containing Al. The organic material containing Al is, for example, trimethylaluminum or dimethylaluminum isopropoxide. The control unit 140 controls the gas supply mechanism 110 to supply oxygen and the organic material containing Al into the chamber 101, while generating plasma in the chamber 101, to form an Al-containing film on the substrate W. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and either trimethylaluminum or dimethylaluminum isopropoxide into the chamber 101, while generating plasma in the chamber 101, to form an Al-containing film on the substrate W. As a result, the film formation apparatus 100 according to the embodiment can form an Al-containing film that is removable with water.

[0064] The precursor is an organic material containing Sc. The organic material containing Sc is, for example, trimethylsilylmethylscandium. The control unit 140 controls the gas supply mechanism 110 to supply oxygen and the organic material containing Sc into the chamber 101, while generating plasma in the chamber 101, and depositing a film containing Sc on the substrate W. For example, the control unit 140 controls the gas supply mechanism 110 to supply oxygen and trimethylsilylmethylscandium into the chamber 101, while generating plasma in the chamber 101, and depositing a film containing Sc on the substrate W. As a result, the film deposition apparatus 100 according to the embodiment can deposit a film containing Sc that is removable with water.

[0065] Furthermore, the control unit 140 controls the temperature of the substrate W to be in the range of 50-300° C. using the support unit 102, thereby controlling the film formation. As a result, the film formation apparatus 100 according to the embodiment can make the film contain a large amount of hydroxide, thereby improving the removability with water.

[0066] Furthermore, the control unit 140 controls the film to be formed on the substrate W under processing conditions that produce a peak at a wave number corresponding to OH in the infrared absorbance spectrum for each wave number measured by FT-IR analysis of the film-formed substrate W. This allows the film-forming apparatus 100 according to the embodiment to contain a large amount of hydroxide in the film, thereby improving removability with water.

[0067] (Others) The technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0068] For example, in the above embodiment, the substrate processing apparatus 200 is a storage type in which water is stored in the processing tank 211, and multiple substrates W are simultaneously immersed in the processing tank 211 to perform wet etching. However, this is not limited to this. The substrate processing apparatus 200 may also be a single-wafer spin cleaning apparatus in which substrates W are placed one by one on a stage, and water is supplied from above the stage while the stage is rotated to perform wet etching on the substrates W.

[0069] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0070] In addition, the following supplementary notes are disclosed regarding the above-described embodiment.

[0071] (Supplementary Note 1) A film formation apparatus comprising: a support part configured to be able to support a substrate and adjust the temperature of the substrate; a processing vessel in which the support part is provided and configured to be able to generate plasma; a gas supply part configured to be able to supply oxygen and any one of Mg, Ge, B, Al, and Sc precursors containing hydrogen or hydrocarbon to the processing vessel; and a control part that controls the temperature of the substrate to be 300°C or less by the support part, and generates plasma in the processing vessel while supplying oxygen and the precursor from the gas supply part into the processing vessel, to form a film containing any one of Mg, Ge, B, Al, and Sc on the substrate.

[0072] (Supplementary Note 2) The film formation apparatus according to Supplementary Note 1, wherein the precursor is an organic material containing Mg, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the organic material containing Mg from the gas supply unit into the processing vessel, thereby forming a film containing Mg on the substrate.

[0073] (Supplementary Note 3) The film formation apparatus according to Supplementary Note 2, wherein the organic material containing Mg is either triethyl magnesium or diethoxy magnesium, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and either the triethyl magnesium or the diethoxy magnesium from the gas supply unit into the processing vessel, thereby forming a film containing Mg on the substrate.

[0074] (Supplementary Note 4) The film formation apparatus according to Supplementary Note 1, wherein the precursor is an organic material containing Ge, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the organic material containing Ge from the gas supply unit into the processing vessel, and to form a film containing Ge on the substrate.

[0075] (Supplementary Note 5) The film formation apparatus according to Supplementary Note 4, wherein the Ge-containing organic material is either trimethylgermanium or tetramethylgermanium, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and either the trimethylgermanium or the tetramethylgermanium from the gas supply unit into the processing vessel, and to form a Ge-containing film on the substrate.

[0076] (Supplementary Note 6) The film formation apparatus according to Supplementary Note 1, wherein the precursor is an organic material containing B, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the organic material containing B from the gas supply unit into the processing vessel, and to form a film containing B on the substrate.

[0077] (Supplementary Note 7) The film formation apparatus according to Supplementary Note 6, wherein the organic material containing B is either trimethyl boron or trisdimethylamino boron, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and either the trimethyl boron or the trisdimethylamino boron from the gas supply unit into the processing vessel, thereby forming a film containing B on the substrate.

[0078] (Supplementary Note 8) The film forming apparatus according to Supplementary Note 1, wherein the precursor is an organic material containing Al, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the organic material containing Al from the gas supply unit into the processing vessel, thereby forming a film containing Al on the substrate.

[0079] (Supplementary Note 9) The film formation apparatus according to Supplementary Note 1, wherein the organic material containing Al is either trimethylaluminum or dimethylaluminum isopropoxide, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and either the trimethylaluminum or the dimethylaluminum isopropoxide from the gas supply unit into the processing vessel, thereby forming a film containing Al on the substrate.

[0080] (Supplementary Note 10) The film forming apparatus according to Supplementary Note 1, wherein the precursor is an organic material containing Sc, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the organic material containing Sc from the gas supply unit into the processing vessel, and to form a film containing Sc on the substrate.

[0081] (Supplementary Note 11) The film formation apparatus according to Supplementary Note 10, wherein the organic material containing Sc is trimethylsilylmethylscandium, and the control unit controls to generate plasma in the processing vessel while supplying oxygen and the trimethylsilylmethylscandium from the gas supply unit into the processing vessel, and to form a film containing Sc on the substrate.

[0082] (Supplementary Note 12) The film forming apparatus according to any one of Supplementary Notes 1 to 11, wherein the control unit controls the temperature of the substrate to a range of 50-300°C by the support unit, and controls the film formation.

[0083] (Supplementary Note 13) The film formation apparatus according to any one of Supplementary Notes 1 to 12, wherein the control unit controls the film to be formed on the substrate under processing conditions such that a peak appears at a wave number corresponding to OH in an infrared absorbance spectrum for each wave number measured by FT-IR (Fourier transform infrared spectroscopy) analysis of the substrate on which the film has been formed.

[0084] (Supplementary Note 14) A film formation method comprising: a) placing a substrate on a support part of a processing vessel, the support part being provided therein and capable of supporting the substrate and adjusting the temperature of the substrate; b) controlling the temperature of the substrate to 300°C or less by the support part; and c) generating plasma in the processing vessel while supplying oxygen and a precursor of any of Mg, Ge, B, Al, and Sc containing hydrogen or a hydrocarbon into the processing vessel, to form a film containing any of Mg, Ge, B, Al, and Sc on the substrate.

[0085] (Supplementary Note 15) A substrate processing method comprising: a) a substrate having a laminate in which a plurality of SiO films and a plurality of GeO films are alternately stacked, and an MgO film or an MgGeO film having a pattern formed on the laminate, the substrate comprising the laminate, the substrate being provided with a mask and etching the laminate.

[0086] (Supplementary Note 16) The substrate processing method according to Supplementary Note 15, further comprising the step of b) wet-etching the MgO film or MgGeO film and each GeO film of the stack all at once.

[0087] (Supplementary Note 17) The substrate processing method according to Supplementary Note 16, wherein the step b) includes side-etching each GeO film of the stack.

[0088] (Supplementary Note 18) The substrate processing method according to Supplementary Note 16 or 17, wherein the step b) performs the wet etching by immersing the substrate in a container containing deionized water or pure water.

[0089] 12 Stacked body 13 Hard mask 22 Stacked body 23 Mask 100 Film forming apparatus 101 Chamber 102 Support part 103 Support member 104 Temperature control mechanism 105 Shower head 106 Shower plate 110 Gas supply mechanism 113 First high frequency power supply 115 Second high frequency power supply 120 Exhaust mechanism 130 Load / unload port 140 Control part 200 Substrate processing apparatus 211 Processing bath 211a Inner bath 211b Outer bath 212 Circulation path 213 Pump 214 Heater 215 Filter 216 Horizontal pipe 217 Substrate holder 218 Liquid supply part 219 Liquid drainage part W Substrate

Claims

1. A film formation apparatus comprising: a support part configured to be able to support a substrate and adjust the temperature of the substrate; a processing vessel configured to be able to generate plasma and to have the support part installed inside; a gas supply part configured to be able to supply oxygen and a precursor of any of Mg, Ge, B, Al, and Sc containing hydrogen or hydrocarbon to the processing vessel; and a control part that controls the temperature of the substrate to be 300°C or less using the support part, and generates plasma in the processing vessel while supplying oxygen and the precursor from the gas supply part into the processing vessel, to form a film containing any of Mg, Ge, B, Al, and Sc on the substrate.

2. The film forming apparatus according to claim 1, wherein the precursor is an organic material containing Mg, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the organic material containing Mg from the gas supply unit into the processing vessel, thereby forming a film containing Mg on the substrate.

3. The film forming apparatus according to claim 2, wherein the organic material containing Mg is either triethyl magnesium or diethoxy magnesium, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and either triethyl magnesium or diethoxy magnesium from the gas supply unit into the processing vessel, thereby forming a film containing Mg on the substrate.

4. The film forming apparatus according to claim 1, wherein the precursor is an organic material containing Ge, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the organic material containing Ge from the gas supply unit into the processing vessel, thereby forming a film containing Ge on the substrate.

5. The film forming apparatus according to claim 4, wherein the organic material containing Ge is either trimethylgermanium or tetramethylgermanium, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and either the trimethylgermanium or the tetramethylgermanium from the gas supply unit into the processing vessel, to form a film containing Ge on the substrate.

6. The film forming apparatus according to claim 1, wherein the precursor is an organic material containing B, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the organic material containing B from the gas supply unit into the processing vessel, thereby forming a film containing B on the substrate.

7. The film forming apparatus according to claim 6, wherein the organic material containing B is either trimethyl boron or trisdimethylamino boron, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and either trimethyl boron or trisdimethylamino boron from the gas supply unit into the processing vessel, thereby forming a film containing B on the substrate.

8. The film forming apparatus according to claim 1, wherein the precursor is an organic material containing Al, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the organic material containing Al from the gas supply unit into the processing vessel, thereby forming a film containing Al on the substrate.

9. The film forming apparatus according to claim 8, wherein the organic material containing Al is either trimethylaluminum or dimethylaluminum isopropoxide, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and either trimethylaluminum or dimethylaluminum isopropoxide from the gas supply unit into the processing vessel, thereby forming a film containing Al on the substrate.

10. The film forming apparatus according to claim 1, wherein the precursor is an organic material containing Sc, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the organic material containing Sc from the gas supply unit into the processing vessel, thereby forming a film containing Sc on the substrate.

11. The film forming apparatus according to claim 10, wherein the organic material containing Sc is trimethylsilylmethylscandium, and the control unit controls the generation of plasma in the processing vessel while supplying oxygen and the trimethylsilylmethylscandium from the gas supply unit into the processing vessel, thereby forming a film containing Sc on the substrate.

12. The film forming apparatus according to claim 1, wherein the control unit controls the temperature of the substrate by the support unit to within a range of 50-300°C, thereby controlling the film formation.

13. The film forming apparatus according to claim 1, wherein the control unit controls the film to be formed on the substrate under processing conditions such that a peak appears at a wave number corresponding to OH in an infrared light absorbance spectrum for each wave number measured by FT-IR (Fourier transform infrared spectroscopy) analysis of the substrate on which the film has been formed.

14. A film formation method comprising the steps of: a) placing a substrate on a support section of a processing vessel having the support section provided therein capable of supporting the substrate and adjusting the temperature of the substrate; b) controlling the temperature of the substrate to 300°C or less using the support section; and c) generating plasma in the processing vessel while supplying oxygen and a precursor of any of Mg, Ge, B, Al, and Sc containing hydrogen or a hydrocarbon into the processing vessel, and forming a film containing any of Mg, Ge, B, Al, and Sc on the substrate.

15. A substrate processing method comprising: a) a substrate having a laminate in which multiple SiO films and multiple GeO films are alternately stacked, and an MgO film or MgGeO film having a pattern formed on the laminate, the substrate comprising the steps of: etching the laminate using the MgO film or MgGeO film as a mask.

16. The substrate processing method according to claim 15, further comprising the step of: b) wet-etching the MgO film or MgGeO film and each GeO film of the stack all at once.

17. The substrate processing method according to claim 16, wherein the step b) includes side etching each GeO film of the stack.

18. The substrate processing method according to claim 16, wherein the wet etching is performed in step b) by immersing the substrate in a container containing deionized water or pure water.

Images