Substrate processing apparatus, substrate processing method, method for manufacturing semiconductor device, and program

Abstract

The present invention provides a technique comprising: a processing chamber in which a substrate is processed by a gas; a plasma generation unit for bringing the gas into a plasma state; a supply pipe provided on the upstream side of the processing chamber; an exhaust pipe provided on the downstream side of the processing chamber; a valve provided on the downstream side of the exhaust pipe; and an attenuation part which is provided in the exhaust pipe at a position closer to the valve than the processing chamber, or upstream of a connection portion between the supply pipe and the processing chamber, and attenuates the energy of the plasma-state gas.

Description

Technical Field

[0001] This disclosure relates to a substrate processing apparatus, a substrate processing method, a method and procedure for manufacturing a semiconductor device. Background Technology

[0002] In a substrate processing apparatus used in a step of the semiconductor device manufacturing process, there are cases where plasma-excited gas is used to perform a predetermined treatment on the substrate (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-144780 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] This disclosure provides a technique for suppressing the deterioration of device components caused by plasma.

[0008] Methods for solving problems

[0009] According to one aspect of this disclosure, a technology having the following components can be provided:

[0010] The processing chamber uses gases to process the substrate;

[0011] A plasma generation unit that sets the gas into a plasma state;

[0012] A supply pipe is located on the upstream side of the processing chamber;

[0013] An exhaust pipe is located on the downstream side of the processing chamber;

[0014] A valve, which is disposed on the downstream side of the exhaust pipe; and

[0015] An attenuation section is provided in the exhaust pipe at a position closer to the valve than the processing chamber, or upstream of the connection between the supply pipe and the processing chamber, to attenuate the energy of the gas in the plasma state.

[0016] Invention Effects

[0017] According to this disclosure, the deterioration of device components caused by plasma can be suppressed. Attached Figure Description

[0018] Figure 1 is a schematic structural diagram of the substrate processing apparatus according to the first embodiment of the present disclosure, which is a longitudinal cross-sectional view of the processing furnace portion.

[0019] Figure 2 is a schematic structural diagram of the controller in the substrate processing apparatus according to the first embodiment of the present disclosure, which is a block diagram showing the control system of the controller.

[0020] Figure 3 is a flowchart illustrating the substrate processing steps of the first embodiment of the present disclosure.

[0021] Figure 4 is an explanatory diagram showing an example of a substrate processed in the substrate processing step of the first embodiment of this disclosure. (A) is a cross-sectional view of the substrate with recesses formed, and (B) is a cross-sectional view of the substrate when the substrate processing step of (A) is performed.

[0022] Figure 5 is a structural diagram of the exhaust section in the substrate processing apparatus of the first embodiment of the present disclosure, and is an enlarged view of section G in Figure 1.

[0023] Figure 6 is an explanatory diagram showing an example of the structure of the attenuation section in the substrate processing apparatus of the first embodiment of the present disclosure. (A) is a perspective view showing the schematic structure, and (B) is a side cross-sectional view showing the cross-sectional structure.

[0024] Figure 7 is an explanatory diagram showing another example of the structure of the attenuation section in the substrate processing apparatus of the first embodiment of the present disclosure.

[0025] Figure 8 is an explanatory diagram showing another example of the structure of the attenuation section in the substrate processing apparatus of the first embodiment of the present disclosure. (A) is a schematic diagram showing a schematic structure, and (B) is a schematic diagram showing other schematic structures.

[0026] Figure 9 is a schematic structural diagram of the substrate processing apparatus according to the second embodiment of the present disclosure, which is a longitudinal cross-sectional view showing the processing furnace portion.

[0027] Figure 10 is a structural diagram of the main parts of the substrate processing apparatus according to the third embodiment of the present disclosure, showing a schematic structure of the plasma generation section.

[0028] Figure 11 is a structural diagram of the main parts of the substrate processing apparatus according to the fourth embodiment of the present disclosure, showing a schematic structure of the gas supply section. Detailed Implementation

[0029] Hereinafter, one aspect of the present disclosure will be described with reference to the accompanying drawings. Furthermore, the drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements shown in the drawings may not correspond to reality. Additionally, the dimensional relationships and ratios of the elements may not be consistent between different drawings.

[0030] <First Implementation>

[0031] First, the first embodiment of this disclosure will be described in detail.

[0032] (1) Substrate processing apparatus

[0033] The following uses Figure 1 The substrate processing apparatus of the first embodiment will be described. Figure 1 This is a schematic structural diagram of the substrate processing apparatus according to the first embodiment.

[0034] The substrate processing apparatus 100 of this embodiment is configured to perform oxidation treatment on the film formed on the surface of the wafer 200, which serves as a substrate.

[0035] (Processing Room)

[0036] The substrate processing apparatus 100 includes a processing furnace 202 for plasma processing of a wafer 200. A processing container 203 constituting a processing chamber 201 is provided in the processing furnace 202. The processing container 203 has a dome-shaped upper container 210 as a first container and a bowl-shaped lower container 211 as a second container. The processing chamber 201 is formed by the upper container 210 covering the lower container 211. The upper container 210 is formed of a non-metallic material such as alumina (Al2O3) or quartz (SiO2), and the lower container 211 is formed of aluminum (Al), for example.

[0037] Additionally, a gate valve 244 is provided on the lower side wall of the lower container 211. When open, the gate valve 244 allows the wafer 200 to be fed into the processing chamber 201 via the inlet / outlet 245 using a conveying mechanism (not shown), or to be moved out of the processing chamber 201. When closed, the gate valve 244 acts as a partition valve to maintain the airtightness of the processing chamber 201.

[0038] The processing chamber 201 includes a plasma generation space 201a surrounded by a resonant coil 212, and a substrate processing space 201b communicating with the plasma generation space 201a and processing the wafer 200. The plasma generation space 201a is the space where plasma is generated; it refers to the space within the processing chamber that is above and below the lower end of the resonant coil 212. On the other hand, the substrate processing space 201b is the space where the wafer 200 is processed using plasma; it refers to the space below the lower end of the resonant coil 212. In this embodiment, the horizontal diameters of the plasma generation space 201a and the substrate processing space 201b are approximately the same.

[0039] (Base)

[0040] A base 217, serving as a substrate mounting portion for placing the wafer 200, is disposed at the center of the bottom side of the processing chamber 201. The base 217 is formed of non-metallic materials such as aluminum nitride (AlN), ceramic, or quartz, and is configured to reduce metal contamination of films formed on the wafer 200.

[0041] A heater 217b, serving as a heating mechanism, is integrally embedded inside the base 217. The heater 217b is configured to heat the surface of the wafer 200 from, for example, 25°C to about 750°C when power is supplied.

[0042] The base 217 is electrically insulated from the lower container 211. To further improve the uniformity of the plasma density generated on the wafer 200 placed on the base 217, an impedance adjustment electrode 217c is disposed inside the base 217 and grounded via an impedance variable mechanism 275, which serves as an impedance adjustment section. The impedance variable mechanism 275 is composed of a coil or a variable capacitor. By adjusting the impedance variable mechanism 275, the potential (bias voltage) of the wafer 200 can be controlled via the impedance adjustment electrode 217c and the base 217.

[0043] A base lifting mechanism 268 is provided on the base 217, and the base lifting mechanism 268 has a drive mechanism for lifting the base. In addition, a through hole 217a is provided on the base 217, and a wafer on-board pusher 266 is provided on the bottom surface of the lower container 211. When the base 217 is lowered by the base lifting mechanism 268, the wafer on-board pusher 266 passes through the through hole 217a without contacting the base 217. The substrate mounting part of this embodiment is mainly composed of the base 217, the heater 217b, and the impedance electrode 217c.

[0044] (Gas Supply Department)

[0045] A gas supply head 236 is provided above the processing chamber 201, specifically at the top of the upper container 210. The gas supply head 236 has a cap-like cover 233, a gas inlet 234, a buffer chamber 237, an opening 238, a shielding plate 240, and a gas outlet 239, enabling the supply of processing gas into the processing chamber 201. The buffer chamber 237 functions as a dispersion space for the processing gas introduced from the gas inlet 234.

[0046] The downstream end of the gas supply pipe 232 is connected to the gas inlet 234. That is, the gas supply pipe 232 is located on the upstream side of the processing chamber 201. At the upstream end of the gas supply pipe 232, the downstream ends of the oxygen-containing gas supply pipe 232a (for supplying oxygen-containing (O) gas), the hydrogen-containing gas supply pipe 232b (for supplying hydrogen-containing (H) gas), and the inert gas supply pipe 232c (for supplying inert gas) are connected in a confluence manner. On the oxygen-containing gas supply pipe 232a, from the upstream side, an O-containing gas supply source 250a, a mass flow controller (MFC) 252a (as a flow control device), and a valve 253a (as an on / off valve) are sequentially provided. On the hydrogen-containing gas supply pipe 232b, from the upstream side, an H-containing gas supply source 250b, an MFC 252b, and a valve 253b are sequentially provided. On the inert gas supply pipe 232c, an inert gas supply source 250c, an MFC 252c, and a valve 253c are sequentially arranged from the upstream side. A valve 243a is located downstream of the confluence of the oxygen-containing gas supply pipe 232a, the hydrogen-containing gas supply pipe 232b, and the inert gas supply pipe 232c, and is connected to the upstream end of the gas inlet 234. By opening and closing valves 253a, 253b, 253c, and 243a, the flow rates of the respective gases can be adjusted via MFCs 252a, 252b, and 252c, and processing gases such as O-containing gas, H-containing gas, and inert gas can be supplied to the processing chamber 201 via the gas supply pipes 232a, 232b, and 232c.

[0047] The oxygen-containing gas supply system of this embodiment mainly consists of oxygen-containing gas supply pipe 232a, MFC 252a, and valve 253a. Furthermore, the hydrogen-containing gas supply system of this embodiment consists of gas supply pipe 232, hydrogen-containing gas supply pipe 232b, MFC 252b, and valve 253b. Moreover, the inert gas supply system of this embodiment consists of gas supply pipe 232, inert gas supply pipe 232c, MFC 252c, and valve 253c.

[0048] In addition, the processing gas supply unit (processing gas supply system) of this method is mainly composed of any one or a combination of an oxygen-containing gas supply system and a hydrogen-containing gas supply system.

[0049] Alternatively, the processing gas supply unit may include any one or a combination thereof, such as a gas supply head 236 (cover 233, gas inlet 234, buffer chamber 237, opening 238, shielding plate 240, gas outlet 239), MFC 252a, 252b, 252c, or an inert gas supply system.

[0050] (Exhaust section)

[0051] A gas exhaust port 235 is provided on the side wall of the lower container 211 to discharge the processed gas from the processing chamber 201. The upstream end of a gas exhaust pipe 231 is connected to the gas exhaust port 235. That is, the gas exhaust pipe 231 is located on the downstream side of the processing chamber 201 and is configured to communicate with the processing chamber 201 via the gas exhaust port 235.

[0052] On the gas exhaust pipe 231, starting from the upstream side, there are sequentially arranged an APC (Auto Pressure Controller) valve 242 as a pressure regulator (pressure adjustment unit), a secondary valve 243b as an on / off valve, a first pump 246 as a vacuum exhaust device, a main valve 243c as an on / off valve, and a second pump 247 as a vacuum exhaust device. The main valve 243c is located on the downstream side of the gas exhaust pipe 231 (that is, on the side near the second pump 247 located at the downstream end of the gas exhaust pipe 231).

[0053] The first pump 246 is used to set the processing chamber 201 to a high vacuum or ultra-high vacuum, and is configured, for example, as a turbomolecular pump. The auxiliary valve 243b functions as an on / off valve attached to the first pump 246, and is configured, for example, as a butterfly valve. The second pump 247 functions as a roughing vacuum pump to supplement the operation of the first pump 246 by venting exhaust gas from atmospheric pressure, and is configured, for example, as a dry vacuum pump. The main valve 243c functions as an on / off valve attached to the second pump 247, and is configured, for example, as a piston valve with a structure that opens and closes by sliding of the valve body.

[0054] Thus, at least a first pump 246, a main valve 243c, and a second pump 247 are provided on the gas exhaust pipe 231. Consequently, the gas exhaust pipe 231 has: a first exhaust pipe 231a connecting the gas exhaust port 235 and the first pump 246; a second exhaust pipe 231b connecting the first pump 246 and the main valve 243c; and a third exhaust pipe 231c connecting the main valve 243c and the second pump 247.

[0055] Furthermore, an attenuation section 248 is provided on the gas exhaust pipe 231, near the main valve 243c in the treatment chamber 201. More specifically, the attenuation section 248 is provided in the second exhaust pipe 231b. The attenuation section 248 will be described in detail later.

[0056] The exhaust section of this embodiment mainly consists of a gas exhaust port 235, a gas exhaust pipe 231, and a secondary valve 243b. Alternatively, the APC valve 242, the first pump 246, and the main valve 243c may also be included in the exhaust section. Furthermore, the second pump 246 may also be included in the exhaust section.

[0057] (Plasma Generation Unit)

[0058] On the outer periphery of the processing chamber 201, that is, on the outer side of the side wall of the upper container 210, a spiral resonant coil 212 serving as the first electrode is provided in a manner that surrounds the processing chamber 201. An RF sensor 272, a high-frequency power supply 273, and a matching circuit 274 for matching the impedance or output frequency of the high-frequency power supply 273 are connected to the resonant coil 212.

[0059] A high-frequency power supply 273 supplies high-frequency power (RF power) to the resonant coil 212. An RF sensor 272 is located on the output side of the high-frequency power supply 273 to monitor information about the supplied high-frequency traveling wave or reflected wave. The reflected wave power monitored by the RF sensor 272 is input to a matching converter 274. The matching converter 274 controls the impedance of the high-frequency power supply 273 or the frequency of the output high-frequency power based on the reflected wave information input from the RF sensor 272 to minimize the reflected wave.

[0060] In order to form a standing wave at a predetermined wavelength, the resonant coil 212 has its winding diameter, winding spacing, and number of windings set in a manner that allows it to resonate at a fixed wavelength. That is, the electrical length of the resonant coil 212 is set to be an integer multiple (1, 2, ...) of the wavelength of the predetermined frequency of the high-frequency power supplied from the high-frequency power source 273.

[0061] The two ends of the resonant coil 212 are electrically grounded, and at least one end is grounded via a movable tap 213 in order to finely adjust the electrical length of the resonant coil when the device is initially set up or the processing conditions change. Figure 1 The symbol 214 in the diagram indicates the fixed ground of the other party. The position of the movable tap 213 is adjusted so that the resonant characteristics of the resonant coil 212 are approximately equal to those of the high-frequency power supply 273. Furthermore, the impedance of the resonant coil 212 can be finely adjusted during the initial setup of the device or when processing conditions change, so a power supply section is formed between the grounding ends of the resonant coil 212 by the movable tap 215. By having a variable grounding section and a variable power supply section in the resonant coil 212, adjustments to the resonant frequency and load impedance of the processing chamber 201 can be made more convenient.

[0062] The plasma generation unit (plasma generation mechanism) of this embodiment mainly consists of a resonant coil 212, an RF sensor 272, and a matching unit 274. Alternatively, a high-frequency power supply 273 may also be included as the plasma generation unit.

[0063] According to this structure, in the resonant coil 212 of this embodiment, since high-frequency power is supplied at the actual resonant frequency of the resonant coil containing plasma (or in a manner that matches the actual impedance of the resonant coil containing plasma), a standing wave is formed in which the phase voltage and the anti-phase voltage are always canceled out. When the electrical length of the resonant coil 212 is the same as the wavelength of the high-frequency power, the highest phase current is generated at the electrical midpoint of the coil (the node where the voltage is zero). Therefore, near the electrical midpoint, there is almost no capacitive coupling with the processing chamber wall or base 217, forming a ring-shaped induced plasma with extremely low potential.

[0064] That is, in this embodiment, the plasma generation unit is configured to have a resonant coil 212 capable of generating plasma within the processing chamber 201. Furthermore, by supplying high-frequency power to the resonant coil 212, inductively coupled plasma (ICP) is generated.

[0065] (Control Department)

[0066] The substrate processing apparatus 100 has a controller 221 that functions as a control unit (control unit) for controlling the operation of each part of the substrate processing apparatus 100.

[0067] The controller 221 is configured to control APC valves 242, 243b, 243c, the first pump 246, and the second pump 247 via signal line A; control the base lifting mechanism 268 via signal line B; control the heater power adjustment mechanism 276 and the impedance variable mechanism 275 via signal line C; control the gate valve 244 via signal line D; control the RF sensor 272, the high-frequency power supply 273, and the matching device 274 via signal line E; and control MFCs 252a-252c and valves 253a-253c and 243a via signal line F.

[0068] Figure 2 This is a block diagram showing the general structure of controller 221.

[0069] like Figure 2 As shown, the controller 221, serving as the control unit (control unit), is configured as a computer equipped with a CPU (Central Processing Unit) 221a, RAM (Random Access Memory) 221b, storage device 221c, and I / O port 221d. The RAM 221b, storage device 221c, and I / O port 221d can exchange data with the CPU 221a via an internal bus 221e. An input / output device 225, such as a touch panel or display, is connected to the controller 221.

[0070] The storage device 221c is configured such as flash memory or HDD (Hard Disk Drive). The storage device 221c readablely stores a control program that controls the operation of the board processing apparatus, a program process that describes the sequence or conditions of the board processing described later, and so on. The process process causes the controller 221 to execute each step in the board processing steps described later, combining them to obtain a predetermined result, thus functioning as a program. Hereinafter, the program process, control program, etc., will be collectively referred to as a program. Furthermore, when using the term "program" in this specification, there may be cases where only the program process unit is included, cases where only the control program unit is included, or cases where both are included. Additionally, RAM 221b is configured as a storage area (working area) for temporarily holding programs or data read by CPU 221a.

[0071] I / O port 221d is connected to the aforementioned MFC252a~252c, valves 253a~253c, 243a, 243b, 243c, gate valve 244, APC valve 242, first pump 246, second pump 247, RF sensor 272, high-frequency power supply 273, matching device 274, base lifting mechanism 268, impedance variable mechanism 275, heater power adjustment mechanism 276, etc.

[0072] CPU 221a is configured to read and execute the control program from storage device 221c, and read the process flow from storage device 221c based on input of operation instructions from input / output device 225. Then, CPU221a controls the opening adjustment of APC valve 242, the opening and closing of valves 243b and 243c, and the start / stop of the first pump 246 and the second pump 247 via I / O port 221d and signal line A, in accordance with the read process information. It controls the lifting action of base lifting mechanism 268 via signal line B, the power supply adjustment action (temperature adjustment action) of heater power adjustment mechanism 276 to heater 217b and the impedance value adjustment action of impedance variable mechanism 275 via signal line C, the opening and closing action of gate valve 244 via signal line D, the operation of RF sensor 272, matching device 274 and high frequency power supply 273 via signal line E, and the flow adjustment action of various gases of MFC 252a~252c, as well as the opening and closing action of valves 253a~253c and 243a via signal line F.

[0073] The controller 221 can be configured to install the aforementioned program stored in an external storage device (e.g., magnetic disks such as magnetic tape, floppy disks, or hard disks; optical discs such as CDs or DVDs; optical disks such as MO; semiconductor memory such as USB memory or memory cards) 226 into a computer. The storage device 221c and the external storage device 226 constitute a computer-readable recording medium. Hereinafter, these will be collectively referred to as recording media. In this specification, the use of the term "recording medium" may indicate that only the storage device 221c is included, only the external storage device 226 is included, or both are included. Alternatively, providing the program to the computer may be done without using the external storage device 226, but rather using a communication unit such as the Internet or a dedicated line.

[0074] (2) Substrate processing process

[0075] Next, regarding the substrate processing steps of the first embodiment of this disclosure, mainly using... Figure 3 Please provide an explanation. Figure 3 This is a flowchart illustrating the substrate processing steps of the first embodiment of this disclosure.

[0076] The substrate processing step in the first embodiment is, for example, a step in the manufacturing process of a semiconductor device such as a flash memory, and is performed by the substrate processing apparatus 100. In the following description, the operation of each part constituting the substrate processing apparatus 100 is controlled by the controller 221.

[0077] In this substrate processing step, for example, for Figure 4 The wafer 200 shown in (A) is processed. Figure 4 This is an explanatory diagram showing an example of a substrate being processed in a substrate processing step. Specifically, for example, such as... Figure 4 As shown in (A), a recess 301 is pre-formed on a wafer 200 serving as a substrate. At least on its surface, a silicon (Si) film 302 and a silicon nitride (SiN) film 303 are formed in the recess 301. That is, in the wafer 200 processed in this substrate processing step, the Si film 302 and the SiN film 303 are exposed inside the recess 301 formed on the wafer 200, and the Si film 302 forms the bottom of the recess 301. The recess 301 is, for example, a trench or a hole, and its aspect ratio is 20 or higher. In this substrate processing step, the recess 301 is oxidized using plasma. The Si film 302 is composed of at least one of monocrystalline silicon (c-Si), amorphous silicon (a-Si), and polycrystalline silicon (Poly-Si).

[0078] Furthermore, in this specification, when the term "substrate" is used, it sometimes refers to "the substrate itself," or "the substrate and the predetermined layers or films formed on its surface, and their laminates (assemblies)" (i.e., the substrate includes the predetermined layers or films formed on its surface). Additionally, when the term "surface of the substrate" is used in this specification, it sometimes refers to "the surface of the substrate itself (exposed surface)," or "the surface of the predetermined layers or films formed on the substrate, i.e., the outermost surface of the substrate as a laminate."

[0079] Therefore, in this specification, the phrase "supplying a predetermined gas to the substrate" can mean either "supplying the predetermined gas directly to the surface (exposed surface) of the substrate itself" or "supplying the predetermined gas to the layer or film formed on the substrate, i.e., to the outermost surface of the substrate as a laminate." Additionally, in this specification, it can mean "forming a predetermined layer (or film) on the layer or film formed on the substrate, i.e., on the outermost surface of the substrate as a laminate."

[0080] Furthermore, the use of the term "wafer" in this specification is the same as the use of the term "substrate." In this case, in the above description, it is sufficient to simply replace "substrate" with "wafer."

[0081] (Substrate handling process S110)

[0082] like Figure 3 As shown, in this substrate processing step, the wafer 200 is first moved into the processing chamber 201.

[0083] Next, gate valve 244 is opened, and wafer 200 is moved from the vacuum transfer chamber adjacent to processing chamber 201 into processing chamber 201 using a wafer transfer mechanism (not shown). The moved wafer 200 is supported on the upper surface of base 217. Furthermore, the wafer transfer mechanism is moved out of processing chamber 201, gate valve 244 is closed, and processing chamber 201 is sealed.

[0084] (Heating / Vacuum Exhaust Process S120)

[0085] Next, the wafer 200, which is being moved into the processing chamber 201, is heated. The heater 217b is preheated, and the wafer 200 is held on a base 217 with the heater 217b embedded within it. The wafer 200 is heated to a predetermined temperature, for example, within the range of 150 to 700°C. Here, the temperature of the wafer 200 is heated to 700°C. Furthermore, during the heating of the wafer 200, a vacuum pump 246 is used to evacuate the processing chamber 201 via a gas exhaust pipe 231, so that the pressure inside the processing chamber 201 reaches a predetermined value. The vacuum pump 246 operates at least until the substrate removal process S160, described later, is completed. Additionally, the expression "150 to 700°C" in this specification means that both the lower and upper limits are included within that range. Therefore, for example, "150 to 700°C" means "between 150°C and 700°C". The same applies to other numerical ranges.

[0086] (Gas supply process S130)

[0087] Next, a mixture of O-containing gas and H-containing gas is supplied as the processing gas. That is, the mixture of O-containing gas and H-containing gas is supplied to the processing chamber 201 containing the wafer 200. Specifically, valves 253a and 253b are opened, and the flow rate is controlled by MFCs 252a and 252b while the O-containing gas and H-containing gas are supplied to the processing chamber 201. At this time, the flow rate of the O-containing gas is set to a predetermined value, for example, 10 to 50,000 sccm, preferably within the range of 10 to 5,000 sccm. Similarly, the flow rate of the H-containing gas is set to a predetermined value, for example, 10 to 50,000 sccm, preferably within the range of 10 to 5,000 sccm.

[0088] The ratio of O to H in the mixture of O-containing and H-containing gases used as the processing gas is adjusted by controlling the flow rate ratio of the O-containing and H-containing gases. This allows for easy control of the O to H ratio in the processing gas. Furthermore, the O to H ratio is the ratio of the number of O atoms to H atoms in the processing gas. For example, when using a mixture of oxygen gas (O2 gas) and hydrogen gas (H2 gas) as the O-containing and H-containing gas mixture, the flow rate ratio of the O-containing and H-containing gases directly becomes the O to H ratio. The flow rate ratio of the O-containing and H-containing gases is adjusted to a value corresponding to a predetermined thickness ratio pre-acquired and stored in storage device 221c or external storage device 226. Thus, by pre-acquired and stored in storage device 221c or external storage device 226, the flow rate ratio of the O-containing and H-containing gases can be easily adjusted.

[0089] At this time, the opening of APC valve 242 is adjusted to control the exhaust in the processing chamber 201, so that the pressure in the processing chamber 201 is, for example, a predetermined pressure in the range of 1~250 Pa, preferably 50~200 Pa, and more preferably about 150 Pa. In this way, while appropriately exhausting the processing chamber 201, O-containing gas and H-containing gas are continuously supplied until the plasma processing step S140 described later is completed.

[0090] (Plasma treatment process S140)

[0091] If the pressure inside the processing chamber 201 stabilizes, high-frequency power is applied to the resonant coil 212 from the high-frequency power supply 273 via the RF sensor 272. In this embodiment, high-frequency power of 13.54 to 27.12 MHz is supplied to the resonant coil 212 from the high-frequency power supply 273. The high-frequency power supplied to the resonant coil 212 is, for example, a predetermined power in the range of 100 to 5000 W.

[0092] Thus, a high-frequency electric field is formed within the plasma generation space 201a, which supplies O- and H-containing gases. Using this electric field, a ring-shaped induced plasma with the highest plasma density is excited at a height equivalent to the electrical midpoint of the resonant coil 212 in the plasma generation space 201a. The plasma-like O- and H-containing gases dissociate, generating oxygen-reactive species such as oxygen (O) radicals, oxygen ions, and hydroxyl (OH) radicals, and hydrogen-reactive species such as hydrogen (H) radicals and hydrogen ions.

[0093] That is, the processing gas, which is a mixture of O-containing gas and H-containing gas supplied to the processing chamber 201, is excited by plasma to generate reactive species such as oxygen-active species or hydrogen-active species. Here, by generating reactive species with oxidizing effects such as oxygen-active species and reactive species with oxidation-inhibiting effects such as hydrogen-active species, selective oxidation of Si films and SiN films can be achieved.

[0094] Furthermore, by using active species generated by ICP with extremely low potential for oxidation, an oxide layer with good uniformity can be formed on the surface of the recess 301 with a high aspect ratio of 20 or more. Additionally, even when the recess 301 is not formed perpendicular to the surface direction of the wafer 200, as in the case where the recess 301 is formed with respect to the surface direction of the wafer 200, an oxide layer with good uniformity can still be formed on its surface.

[0095] That is, such as Figure 4As shown in (B), a uniformly thick SiO layer 304a is formed on the exposed surface of the Si film 302 constituting the bottom of the recess 301, and a uniformly thick SiO layer 304b is formed on the exposed surface of the SiN layer 303 constituting the sidewall of the recess 301. Furthermore, a SiO layer 304a with a greater thickness than the SiO layer 304b formed on the exposed surface of the Si film 302 constituting the bottom of the recess 301 is formed on the exposed surface of the Si film 302. That is, the surface of the silicon film 304 can be selectively oxidized on the surface of the SiN film 303 to form the SiO layer 304a as an oxide layer.

[0096] Then, if a predetermined processing time, such as 10 to 300 seconds, has elapsed, the power output from the high-frequency power supply 273 is stopped, and the plasma discharge within the processing chamber 201 is halted. Additionally, valves 253a and 253b are closed, stopping the supply of O-containing and H-containing gases to the processing chamber 201. Thus, the plasma processing step S140 is completed.

[0097] (Vacuum exhaust process S150)

[0098] If the supply of O-containing and H-containing gases is stopped, vacuum exhaust is performed on the processing chamber 201 via gas exhaust pipe 231. This discharges the O-containing or H-containing gases, as well as the waste gases generated from the reaction of these gases, from the processing chamber 201 to the outside. Then, the opening of APC valve 242 is adjusted to bring the pressure inside the processing chamber 201 to the same level as the pressure in the adjacent vacuum transfer chamber (the destination of wafer 200, not shown).

[0099] (Substrate removal process S160)

[0100] If the pressure inside the processing chamber 201 reaches the predetermined level, the base 217 is lowered to the wafer 200 transport position, and the wafer 200 is supported on the wafer pusher 266. Then, the gate valve 244 is opened, and the wafer transport mechanism is used to move the wafer 200 out of the processing chamber 201. This concludes the substrate processing step of this embodiment.

[0101] Examples of gases containing oxygen include O2, ozone (O3), water vapor (H2O), hydrogen peroxide (H2O2), nitric oxide (NO), and nitrous oxide (N2O). Furthermore, gases containing at least one of these can also be used as oxygen-containing gases.

[0102] In addition, as the H-containing gas, for example, H2 gas, H2O gas, H2O2 gas, deuterium (D2) gas, etc. can be used. Furthermore, as the H-containing gas, a gas containing at least one of these can be used.

[0103] Furthermore, O-containing gases and H-containing gases use different gases. For example, O-containing gases and H-containing gases use gases with different ratios of O atoms to H atoms in each gas flow rate. Additionally, O-containing gases and H-containing gases use gases with different ratios of O atoms to H atoms in their respective gas compositions (molecular structures).

[0104] (3) Plasma attenuation

[0105] In the aforementioned substrate processing steps, in the plasma processing step S140, the wafer 200 is processed using a plasma-excited processing gas. At this time, if the wafer 200 to be processed has a high aspect ratio trench-like portion on its surface (specifically, for example, a recess 301), it is preferable that the free radicals have high energy levels. In order to uniformly process the high aspect ratio trench from the top to the bottom, it is necessary for the free radicals to reach the depth of the trench. However, if the energy level of the free radicals is low, they may be deactivated midway through the trench, creating the possibility that the free radicals cannot reach the bottom of the trench.

[0106] On the other hand, during the processing of wafer 200, from the start of the processing gas supply step S130 to the end of the plasma processing step S140, the exhaust gas from the gas exhaust pipe 231 is controlled to adjust the pressure inside the processing chamber 201 to a predetermined level. Furthermore, after the plasma processing step S140 ends, during the vacuum exhaust step S150, the processing gas inside the processing chamber 201 is discharged from the gas exhaust pipe 231. Therefore, the plasma-state processing gas flows into the gas exhaust pipe 231, which constitutes the exhaust section.

[0107] In this case, the processing gas in the plasma state may cause deterioration of the components of the exhaust section under the influence of the plasma. In particular, when the energy level of the free radicals is high, the degree of deterioration of the components of the exhaust section is considered to be greater.

[0108] Figure 5 This is a structural diagram of the exhaust section in this embodiment. Figure 1 An enlarged view of part G in the image. (See image below.) Figure 5As shown, in the exhaust section, the gas exhaust pipe 231 has at least a second exhaust pipe 231b and a third exhaust pipe 231c, and a main valve 243c is provided between the second exhaust pipe 231b and the third exhaust pipe 231c. The main valve 243c has a valve body 249a and a sealing member 249b, which are positioned on the extension line of the gas exhaust pipe 231 (especially the second exhaust pipe 231b). The operation of the valve body 249a is controlled by a controller 221. An O-ring is used, for example, as the sealing member 249b. The sealing member 249b is positioned opposite the downstream opening of the gas exhaust pipe 231 (especially the second exhaust pipe 231b).

[0109] In this exhaust section with such a structure, when the plasma-state processed gas flowing into the gas exhaust pipe 231 directly reaches the main valve 243c, the plasma will be disrupted by the sealing component 249b, which may cause the sealing component 249b to deteriorate. In the case of deterioration, it is considered that the original function of the sealing component 249b cannot be fully utilized.

[0110] However, in this embodiment, an attenuation section 248 is provided on the gas exhaust pipe 231 constituting the exhaust section. More specifically, the attenuation section 248 is provided in the gas exhaust pipe 231 at a position closer to the main valve 243c than the processing chamber 201, and more specifically, it is provided on the second exhaust pipe 231b. That is, the attenuation section 248 is provided at least upstream of the main valve 243c.

[0111] The attenuation section 248 attenuates the energy of the plasma-state processing gas. If such an attenuation section 248 is provided at least upstream of the main valve 243c, the plasma-state processing gas will not directly reach the main valve 243c even when it flows into the gas exhaust pipe 231. The plasma-state processing gas flowing into the gas exhaust pipe 231 passes through the attenuation section 248, thereby attenuating the plasma's energy. Therefore, the processing gas, after energy attenuation caused by the attenuation section 248, reaches the main valve 243c, thus suppressing damage to the sealing member 249b through plasma energy attenuation.

[0112] That is, according to this embodiment, by having attenuation section 248, the energy of the plasma can be attenuated near the sealing member 249b without affecting the atmosphere inside the processing chamber 201. As a result, even when processing gas in plasma state flows into the gas exhaust pipe 231, the deterioration of the device components caused by plasma, especially the deterioration of the sealing member 249b of the main valve 243c, can be suppressed.

[0113] In particular, as in this embodiment, if the sealing member 249b in the main valve 243c is positioned close to the downstream opening of the second exhaust pipe 231b, there is a concern that the sealing member 249b may easily deteriorate. However, even in this case, the attenuation section 248 attenuates the energy of the plasma, thereby reliably suppressing the deterioration of the sealing member 249b and eliminating the aforementioned concern.

[0114] Furthermore, if the attenuation section 248 is provided, the deterioration of the sealing component can be suppressed, thus enabling a sufficient amount of plasma to be supplied to the exposed surface of the Si film 302 that forms the bottom of the recess 301.

[0115] (Structure of the attenuation section)

[0116] Here, specific examples are given to illustrate the structure of the attenuation section 248.

[0117] Figure 6 This is an explanatory diagram showing an example of the structure of the attenuation section 248.

[0118] like Figure 6 As shown in (A) and (B), the attenuation section 248 exemplified here has at least: a plate-shaped first structural section 248b having a plurality of first through holes 248a; and a plate-shaped second structural section 248d having a plurality of second through holes 248c. In each structural section 248b and 248d, the plate-shaped structure between the through holes 248a and 248c is referred to as a gas collision wall 248s and 248t. The second structural section 248d is disposed downstream of the gas flow in the gas exhaust pipe 231 relative to the first structural section 248b. When viewed from the airflow direction, the gas collision walls 248t of the first through holes 248a in the first structural section 248b and the second through holes 248c in the second structural section 248d at least partially overlap. For example, the above structure can also be achieved by arranging the first through holes 248a and the second through holes 248c in a manner where they do not overlap. The first structural part 248b and the second structural part 248d may each have at least one, but they may also be arranged alternately as shown in the example.

[0119] The attenuation section 248 of this structure is used in the gas flow path of the gas exhaust pipe 231 so that the gas flow in the gas exhaust pipe 231 passes sequentially through the first through hole 248a and the second through hole 248c. When the gas passes through the attenuation section 248, a portion of the gas collides with the gas collision wall 248s of the first structural section 248b. The remaining gas is configured such that at least a portion of the gas collision wall 248t of the first through hole 248a and the second structural section 248d overlaps with the gas collision wall 248t of the second structural section 248d, and therefore collides with the gas collision wall 248t of the second structural section 248d. Thus, the energy of the plasma can be attenuated for the gas passing through the attenuation section 248.

[0120] If the energy of the plasma can be attenuated, then... Figure 6 As shown, the structure of the attenuation part 248 is not limited to the structure that combines the first structural part 248b and the second through hole 248c.

[0121] For example, the attenuation section 248 may also have a gas collision section that collides with the airflow within the gas exhaust pipe 231. Specific examples of the gas collision section include a crank structure section that combines multiple gas flow directions with curved sections, or a curved pipe section consisting of a single curved section. If such a gas collision section is provided, the gas collides with the inner wall surface of the gas exhaust pipe 231 that constitutes the gas collision section when it passes through it. Therefore, the energy of the plasma can be attenuated for the gas passing through the gas collision section.

[0122] When the attenuation section 248 has a gas collision section, the gas collision section may also have a deactivation section that deactivates the energy of the gas in the plasma state. Specific examples of the deactivation section attached to the gas collision section include hardware structures that increase the probability of gas colliding with the gas collision section (e.g., a wind guide component), gas adsorption components attached to the gas collision section, etc. If such a deactivation section is provided, it deactivates the energy of the plasma, thus being very effective in attenuating the energy of the plasma.

[0123] Alternatively, the attenuation section 248 can also have the following structure.

[0124] Figure 7 This is an explanatory diagram showing another example of the structure of the attenuation section 248.

[0125] like Figure 7 As shown, the attenuation section 248 exemplified here utilizes an inert gas to attenuate the energy of the plasma. That is, the attenuation section 248 may also have an inert gas supply section 248e capable of supplying inert gas to the gas flow from the gas exhaust pipe 231. For example, nitrogen (N2) gas can be used as the inert gas. However, it is not limited to this. Besides N2 gas, rare gases such as argon (Ar), helium (He), neon (Ne), and xenon (Xe) gas can also be used as the inert gas. If such an inert gas supply section 248e is provided, the energy of the plasma can be attenuated by supplying inert gas from the inert gas supply section 248e to the gas passing through the gas collision section, causing collisions with the plasma.

[0126] Figure 8 This is an explanatory diagram showing another example of the structure of the attenuation section 248.

[0127] like Figure 8As shown in (A) and (B), the attenuation section 248 exemplified here attenuates the energy of the plasma by directing the gas flow direction to the opposite direction of gravity. That is, the attenuation section 248 may also have a rising section 248f, which directs the gas flow direction of the gas exhaust pipe 231 to the opposite direction of gravity. With such a rising section 248f, an airflow can be formed in the direction opposite to gravity, thereby increasing the collision probability of the plasma in the gas, and consequently, attenuating the energy of the plasma in the gas.

[0128] In this embodiment, the attenuation section 248 can be constructed from any of the above-described specific examples, or it can be constructed by appropriately combining multiple specific examples. That is, the attenuation section 248 is located at least upstream of the main valve 243c, and it is only necessary to be able to attenuate the energy of the plasma of the processed gas flowing in the gas exhaust pipe 231.

[0129] (Configuration of the attenuation section)

[0130] As described above, the attenuation section 248 of the above structure is located in the gas exhaust pipe 231 at least upstream of the main valve 243c, closer to the main valve 243c than the processing chamber 201. Hereinafter, specific examples will be given to further explain in detail the location of the attenuation section 248 on the gas exhaust pipe 231.

[0131] In this embodiment, such as Figure 1 As shown, on the gas exhaust pipe 231, an APC valve 242, a secondary valve 243b, and a first pump 246 are provided on one side of the processing chamber 201. An attenuation section 248 is positioned downstream of the first pump 246 (i.e., closer to the main valve 243c). That is, the attenuation section 248 is located between the first pump 246 and the main valve 243c. More specifically, the attenuation section 248 is located on the second exhaust pipe 231b, which connects the first pump 246 and the main valve 243c, one of the first exhaust pipe 231a, the second exhaust pipe 231b, and the third exhaust pipe 231c constituting the gas exhaust pipe 231.

[0132] The first pump 246 is, for example, a turbomolecular pump. However, if an attenuation section 248 is provided upstream of the first pump 246, particles generated from the attenuation section 248 may flow back into the processing chamber 201 for some reason, potentially affecting the substrate processing. In contrast, by arranging the attenuation section 248 downstream of the first pump 246, the influence of the attenuation section 248 on the atmosphere within the processing chamber 201 can be reduced, even if the conductivity through the attenuation section 248 is high.

[0133] Furthermore, if the attenuation section 248 is provided upstream of the first pump 246, the conductivity of the attenuation section 248 must be considered when controlling the first pump 246, which complicates the control, for example, in the case of pressure control. In contrast, by placing the attenuation section 248 downstream of the first pump 246, the conductivity of the attenuation section 248 does not need to be considered when controlling the first pump 246, thus avoiding the complexity of the control.

[0134] In addition, in this embodiment, such as Figure 5 As shown, in the gas exhaust pipe 231, there is a flow rate variation section 248g upstream of the main valve 243c, where the gas flow rate varies. Furthermore, a damping section 248 is provided on the flow rate variation section 248g.

[0135] The velocity variation section 248g is located within the gas exhaust pipe 231, where the velocity of the gas flowing in the gas exhaust pipe 231 increases. Specifically, it is the section where the gas velocity downstream of the velocity variation section 248g is greater than the gas velocity upstream. The structure of the velocity variation section 248g will be described below with specific examples.

[0136] For example, the flow rate variation unit 248g is composed of a piping section connected to the downstream side of the first pump 246. That is, the flow rate variation unit 248g is composed of a piping section that becomes the second exhaust pipe 231b. This piping section can function as the flow rate variation unit 248g because the gas flow rate increases under the influence of the first pump 246.

[0137] Furthermore, for example, there is a portion 231d upstream of the flow rate variation section 248g where the gas flow direction of the gas exhaust pipe 231 changes. This portion 231d can be part of the first pump 246 or part of the second exhaust pipe 231b in the gas exhaust pipe 231. In either case, this portion 231d constitutes a bend in the gas flow path of the gas exhaust pipe 231. If this portion 231d exists, the gas velocity increases in the piping section downstream of it due to the change in gas flow direction, thus enabling it to function as the flow rate variation section 248g.

[0138] Furthermore, for example, the downstream end of the second exhaust pipe 231b is connected to the inlet flow path 249c that constitutes the main valve 243c, but the diameter of the inlet flow path 249c (see D1 in the figure) is smaller than the diameter of the second exhaust pipe 231b (see D2 in the figure). According to this structure, due to the small diameter of the inlet flow path 249c, there is a situation where the gas velocity in the second exhaust pipe 231b is greater than that in the first exhaust pipe 231a. Therefore, the second exhaust pipe 231b can function as a flow velocity variation part 248g.

[0139] Furthermore, for example, the diameter of the second exhaust pipe 231b is configured to be smaller than the diameter of the first exhaust pipe 231a. According to this structure, due to the small diameter of the inlet flow path 249c, there is a situation where the gas flow velocity in the second exhaust pipe 231b is greater than that in the first exhaust pipe 231a. Therefore, the second exhaust pipe 231b can function as a flow velocity variation part 248g.

[0140] In this embodiment, the velocity variation section 248g can be constructed from any of the above-described specific examples, or it can be constructed by appropriately combining multiple specific examples. That is, the velocity variation section 248g only needs to be a part where the velocity of the gas flowing in the gas exhaust pipe 231 locally increases, at least upstream of the main valve 243c.

[0141] If an attenuation section 248 is provided on the velocity variation section 248g as described above, then the velocity variation section 248g exists in the region where the gas velocity increases. Therefore, compared to the case where the velocity does not increase, the probability of the gas colliding with the attenuation section 248 increases. Thus, for the gas passing through the attenuation section 248, the energy attenuation efficiency of the plasma can be improved.

[0142] For example, if the gas velocity upstream of the main valve 243c increases, and the gas directly reaches the main valve 243c, more plasma will be generated due to the increased velocity. Therefore, there is concern that the plasma may cause increased damage to sealing components such as 249b in the main valve 243c, and the mass of these sealing components such as 249b may increase.

[0143] However, in this embodiment, as described above, by providing the attenuation section 248 in the flow rate variation section 248g, the energy of the plasma can be effectively attenuated. That is, even if the gas flow rate in the flow rate variation section 248g increases, the plasma can be deactivated by the attenuation section 248 before the plasma damages the sealing component 249b, etc. Therefore, even if the gas flow rate upstream of the main valve 243c increases, the deterioration caused by the plasma damaging the sealing component 249b, etc., can be suppressed.

[0144] In particular, when the second exhaust pipe 231b has a smaller diameter than the first exhaust pipe 231a, the conductivity of the second exhaust pipe 231b is greater than that of the first exhaust pipe 231a, thus increasing the collision coefficient. Therefore, plasma deactivation is more likely to occur in the second exhaust pipe 231b compared to the first exhaust pipe. Furthermore, if the second exhaust pipe 231b has a smaller diameter than the first exhaust pipe 231a, a smaller attenuation section 248 can be provided, thereby reducing component costs.

[0145] As described above, the attenuation section 248 is provided on the second exhaust pipe 231b connecting the first pump 246 and the main valve 243c. In this case, from the viewpoint of suppressing the deterioration of the sealing component 249b, etc., of the main valve 243c, it is preferable that the attenuation section 248 is located before the main valve 243c. Moreover, considering that there is a flow rate variation section 248g upstream of the main valve 243c, it is preferable that the attenuation section 248 is provided on the flow rate variation section 248g. With this configuration, the attenuation section 248 can reliably suppress the deterioration of the sealing component 249b, etc., of the main valve 243c.

[0146] (4) Effects of this implementation method

[0147] According to this embodiment, one or more of the following effects are achieved.

[0148] (a) According to this embodiment, since the attenuation section 248 is located in the gas exhaust pipe 231 closer to the main valve 243c than the processing chamber 201, it does not affect the atmosphere inside the processing chamber 201, and the energy of the plasma-state processing gas flowing through the gas exhaust pipe 231 is attenuated. Therefore, even when the plasma-state processing gas flows into the gas exhaust pipe 231, the deterioration of the device components caused by the plasma can be suppressed, especially the deterioration of the sealing component 249b of the main valve 243c.

[0149] (b) According to this embodiment, since the attenuation section 248 is provided on the velocity variation section 248g, even if the gas velocity in the velocity variation section 248g increases, the plasma can be deactivated by the attenuation section 248 before the plasma damages the sealing member 249b, etc. That is, in the velocity variation section 248g, the collision probability of the gas in the attenuation section 248 increases, thereby improving the energy attenuation efficiency of the plasma. Therefore, it is very useful in suppressing deterioration caused by the plasma damaging the sealing member 249b, etc.

[0150] (c) According to this embodiment, for example, the velocity variation section 248g is constituted by a piping section connected to the downstream side of the first pump 246, a piping section downstream of the gas flow direction change section 231d, a portion of the second exhaust pipe 231b with a larger diameter than the inlet flow path 249c of the main valve 243c, and a portion of the second exhaust pipe 231b with a smaller diameter than the first exhaust pipe 231a. Therefore, the gas velocity can be increased in the velocity variation section 248g, thereby increasing the probability of gas collision. That is, it is very useful in improving the attenuation efficiency of plasma energy.

[0151] (d) According to this embodiment, the valve body 249a and sealing member 249b of the main valve 243c are arranged on the extension line of the gas exhaust pipe 231 (especially the second exhaust pipe 231b). Even if the sealing member 249b is arranged at a position opposite to the downstream port of the second exhaust pipe 231b, the energy of the plasma is attenuated by the attenuation part 248, and the deterioration caused by the plasma damage to the sealing member 249b, etc., can be suppressed.

[0152] (e) According to this embodiment, since the attenuation section 248 is provided on the second exhaust pipe 231b, the attenuation section 248 is disposed downstream of the first pump 246. Therefore, even if the conductivity increases through the attenuation section 248, the influence of the attenuation section 248 on the atmosphere inside the processing chamber 201 can be reduced. Moreover, the conductivity of the attenuation section 248 does not need to be considered when controlling the first pump 246, thus avoiding any complexity in the control process.

[0153] (f) According to this embodiment, since the second exhaust pipe 231b has a smaller diameter than the first exhaust pipe 231a, the conductivity of the second exhaust pipe 231b is greater than that of the first exhaust pipe 231a, thereby increasing the collision coefficient of the second exhaust pipe 231b. Therefore, if the attenuation part 248 is provided in the second exhaust pipe 231b, plasma deactivation is easier compared to the case where it is provided in the first exhaust pipe 231a. Moreover, since the second exhaust pipe 231b has a smaller diameter than the first exhaust pipe 231a, a smaller attenuation part 248 can be provided, thus reducing component costs.

[0154] (g) According to this embodiment, for example, the attenuation section 248 may be composed of the following components: a structure having a first structural section 248b and a second structural section 248d; a structure having a gas collision section that collides with the airflow in the gas exhaust pipe 231; a structure having a deactivation section attached to the gas collision section; a structure having an inert gas supply section 248e that can supply inert gas to the airflow; and a structure having an ascending section 248f in which the gas flow direction of the gas exhaust pipe 231 is opposite to the direction of gravity. If the attenuation section 248 is configured in this way, the collision probability of plasma in the gas can be increased, and the plasma can be deactivated and its energy reliably attenuated.

[0155] (h) According to this embodiment, the plasma generation unit has a resonant coil 212 capable of generating plasma within the processing chamber 201, and ICP generation is performed using this resonant coil 212. When using ICP, a greater number of free radicals can be generated, thus allowing for appropriate processing, even when processing a wafer 200 with a high aspect ratio recess 301 on its surface. However, if more free radicals are generated using ICP, the degradation caused by the amount of free radicals may increase. But according to this embodiment, since an attenuation section 248 is provided to attenuate the plasma energy, degradation of device components caused by plasma, particularly the sealing component 249b of the main valve 243c, can be suppressed even when using ICP.

[0156] <Second Implementation>

[0157] Next, the second embodiment of the present invention will be described in detail. Here, the differences from the first embodiment described above will be mainly explained, and other aspects will be omitted.

[0158] The structure of the exhaust section of the substrate processing apparatus 100 described in this embodiment is different from that in the first embodiment.

[0159] Figure 9 This is a schematic configuration diagram of the substrate processing apparatus according to the second embodiment.

[0160] The exhaust section in this embodiment is configured to include a gas exhaust port 235, a gas exhaust pipe 231, and an APC valve 242. Alternatively, the main valve 243c and the second pump 246 may be included in the exhaust section. Thus, in this embodiment, the auxiliary valve 243b and the first pump 246 described in the first embodiment are not provided in the exhaust section.

[0161] However, the attenuation section 248 and the flow rate variation section 248g are configured in the same way as in the first embodiment. That is, the attenuation section 248 is provided in the gas exhaust pipe 231 closer to the main valve 243c than the processing chamber 201, and more specifically, it is provided on the second exhaust pipe 231b, located upstream (preferably upstream) of the main valve 243c. Moreover, at this location, the attenuation section 248 attenuates the energy of the plasma of the passing gas. In addition, in this embodiment, the flow rate variation section 248g is provided in the gas exhaust pipe 231 upstream of the main valve 243c. Moreover, the attenuation section 248 is provided on the flow rate variation section 248g.

[0162] In this embodiment described above, one or more effects described in the first embodiment are also achieved.

[0163] <Third Implementation Method>

[0164] Next, the third embodiment of the present invention will be described in detail. Here, the differences from the first or second embodiment described above will be mainly explained, and other aspects will be omitted.

[0165] In the substrate processing apparatus 100 described in this embodiment, the structure of the plasma generation unit is different from that in the first embodiment or the second embodiment.

[0166] Figure 10 This is a structural diagram of the main parts of the substrate processing apparatus according to the third embodiment.

[0167] In this embodiment, a spiral first resonant coil (hereinafter referred to as "first coil") 212a and a spiral second resonant coil (hereinafter referred to as "second coil") 212b are provided on the outer periphery of the processing chamber 201, i.e., on the outer side of the side wall of the upper container 210, in a manner that surrounds the processing chamber 201. The first coil 212a is connected to the RF sensor 272a, the high-frequency power supply 273a, and the matching device 274a, and generates an ICP within the processing chamber 201 by supplying high-frequency power. Similarly, the second coil 212b is connected to the RF sensor 272b, the high-frequency power supply 273b, and the matching device 274b, and generates an ICP within the processing chamber 201 by supplying high-frequency power.

[0168] That is, in this embodiment, the plasma generation unit has a first coil 212a capable of generating plasma in the processing chamber 201, and a second coil 212b adjacent to the first coil 212a and capable of generating plasma in the processing chamber 201. Other structures can be the same as in the first or second embodiment.

[0169] According to this embodiment, since the first coil 212a and the second coil 212b function as a dual coil, the amount of free radicals in the ICP increases. Therefore, it is very useful, for example, as in the case of processing a wafer 200 with a high aspect ratio recess 301 on its surface, even when a large number of free radicals are required.

[0170] Furthermore, even if the amount of ICP radicals increases, the presence of the attenuation section 248 can suppress the deterioration of the device components caused by plasma, particularly the deterioration of the sealing component 249b of the main valve 243c. That is, in this embodiment, one or more of the effects described in the first or second embodiment are also achieved.

[0171] <Fourth Implementation>

[0172] Next, the fourth embodiment of the present invention will be described in detail. Here, the differences from the first, second, or third embodiments described above will be mainly explained, and other aspects will be omitted.

[0173] The structure of the gas supply section and plasma generation section of the substrate processing apparatus 100 described in this embodiment is different from that in the first embodiment, the second embodiment, or the third embodiment.

[0174] Figure 11 This is a structural diagram of the main parts of the substrate processing apparatus according to the fourth embodiment.

[0175] In this embodiment, a remote plasma unit (RPU) 254 is provided on the gas supply pipe 232 constituting the gas supply unit. The RPU 254 converts the processing gas flowing in the gas supply pipe 232 into a plasma state.

[0176] That is, RPU254 functions as the plasma generation unit (plasma generation mechanism) in this embodiment. Therefore, in this embodiment, none of the resonant coil 212 described in the first embodiment, the first coil 212a described in the third embodiment, and the second coil 212b are provided.

[0177] According to this embodiment, when processing the wafer 200 in the processing chamber 201, the RPU 254 supplies the processing gas from the gas supply pipe 232 into the processing chamber 201 in a plasma state.

[0178] In this situation, it may not be easy to precisely control the plasma energy level and free radical quantity in the RPU254. Therefore, if sufficient energy level is required to process the wafer 200, the plasma energy may actually become excessive. If gas is supplied to the processing chamber 201 through the gas inlet 234 under such excessive energy conditions, the plasma may, for example, damage the sealing components 234a, such as the O-ring at the connection between the sealed processing container 203 and the gas supply pipe 232, and thus the sealing components 234a may deteriorate due to this effect.

[0179] Therefore, in this embodiment, an attenuation section 248 is provided on the gas supply pipe 232. More specifically, the attenuation section 248 is provided upstream of the connection between the processing container 203 constituting the processing chamber 201 and the gas supply pipe 232. The attenuation section 248 may be the same as in the first embodiment, the second embodiment, or the third embodiment.

[0180] Furthermore, similar to the first, second, or third embodiments, the attenuation portion 248 may also be provided in the flow rate variation portion 248g. That is, in this embodiment, the flow rate variation portion 248g may also exist in the gas supply pipe 232.

[0181] According to this embodiment with the above structure, since an attenuation section 248 is provided upstream of the connection between the gas supply pipe 232 and the processing container 203, the energy of the plasma-state processing gas flowing through the gas supply pipe 232 can be attenuated. Therefore, even if the energy of the plasma caused by the RPU 254 is too high, the attenuation section 248 attenuates the plasma energy, preventing any impact on the atmosphere inside the processing chamber 201. This suppresses deterioration of the device components caused by the plasma, and in particular, suppresses deterioration of the sealing member 234a at the connection between the processing container 203 and the gas supply pipe 232.

[0182] That is, in this embodiment, in addition to the differences between the gas supply section side and the exhaust section side, one or more effects described in the first embodiment, the second embodiment, or the third embodiment are also achieved.

[0183] <Other Implementation Methods>

[0184] The various embodiments of this disclosure have been described in detail above. However, this disclosure is not limited to the above embodiments and can be used in combination as appropriate, and various changes can be made without departing from its spirit.

[0185] For example, in the embodiments described above, an oxidation process is performed on the wafer 200 during the substrate processing step, but the present invention is not limited to this. That is, any process using plasma can be used, in addition to oxidation, for film formation or forming a metal-containing film. In other words, the present invention is applicable to other substrate processes such as oxidation, nitriding, film formation, annealing, diffusion, and photolithography. Furthermore, the present invention is also applicable to other substrate processing apparatuses, such as annealing apparatuses, oxidation apparatuses, nitriding apparatuses, exposure apparatuses, coating apparatuses, drying apparatuses, heating apparatuses, and plasma-based processing apparatuses. Additionally, these apparatuses can be combined in this disclosure. Furthermore, a portion of the structure of one embodiment can be replaced with the structure of another embodiment, and a structure of another embodiment can be added to the structure of one embodiment. Furthermore, for a portion of the structure of each embodiment, other structures can be added, deleted, or replaced.

[0186] Furthermore, the processing gas that becomes plasma is not limited to O-containing gas and H-containing gas; other types of gases may be used depending on the processing performed in the substrate processing step.

[0187] Symbol Explanation

[0188] 100 substrate processing apparatus

[0189] 200 wafers (substrate)

[0190] 201 Processing Room

[0191] 212 resonant coil

[0192] 221 controller

[0193] 232 gas supply pipe

[0194] 231 Gas Exhaust Pipe

[0195] 243c main valve

[0196] 246 First Pump

[0197] 248 attenuation section.

Claims

1. A substrate processing apparatus characterized by comprising: have: The processing chamber uses gases to process the substrate; A plasma generation unit that sets the gas into a plasma state; A supply pipe is located on the upstream side of the processing chamber; An exhaust pipe is located on the downstream side of the processing chamber; A valve is located on the downstream side of the exhaust pipe; as well as An attenuation section is provided in the exhaust pipe at a position closer to the valve than the processing chamber, or upstream of the connection between the supply pipe and the processing chamber, to attenuate the energy of the gas in the plasma state.

2. The substrate processing apparatus according to claim 1, characterized in that, The attenuation section is disposed in the velocity variation section of the gas flow rate variation.

3. The substrate processing apparatus according to claim 2, characterized in that, The velocity variation section is the part in the exhaust pipe or supply pipe where the gas velocity increases.

4. The substrate processing apparatus according to claim 2, characterized in that, The velocity variation section is a piping section connected to the downstream side of the first pump located in the gas flow path of the exhaust pipe.

5. The substrate processing apparatus according to claim 2, characterized in that, There is a location upstream of the velocity variation section where the gas flow direction changes in the supply pipe, or a location where the gas flow direction changes in the exhaust pipe.

6. The substrate processing apparatus according to claim 1, characterized in that, The valve has a valve body and a sealing component, which are positioned on the extension line of the supply pipe or the exhaust pipe.

7. The substrate processing apparatus according to claim 6, characterized in that, The sealing component is positioned opposite the downstream opening of the supply pipe or the exhaust pipe.

8. The substrate processing apparatus according to claim 6, characterized in that, The diameter of the inlet flow path constituting the valve is configured to be smaller than the diameter of the supply pipe or the exhaust pipe.

9. The substrate processing apparatus according to claim 1, characterized in that, The exhaust pipe is configured to communicate with the processing chamber via an exhaust port located within the processing chamber. Furthermore, the exhaust pipe includes a first exhaust pipe connecting a first pump disposed in the gas flow path of the exhaust pipe to the exhaust port, and a second exhaust pipe connecting the first pump to the valve. The attenuation section is located on the second exhaust pipe.

10. The substrate processing apparatus according to claim 9, characterized in that, The diameter of the second exhaust pipe is smaller than the diameter of the first exhaust pipe.

11. The substrate processing apparatus according to claim 1, characterized in that, The attenuation section includes at least: a first structural section having a plurality of first through holes; and a second structural section disposed downstream of the first structural section, having a plurality of second through holes and a gas collision structure disposed between the second through holes. The first through hole is configured to overlap with the gas collision wall in at least a portion.

12. The substrate processing apparatus according to claim 1, characterized in that, The plasma generation unit has a coil capable of generating plasma within the processing chamber.

13. The substrate processing apparatus according to claim 1, characterized in that, The plasma generation unit includes: a first coil capable of generating plasma within the processing chamber; and a second coil adjacent to the first coil capable of generating plasma within the processing chamber.

14. The substrate processing apparatus according to claim 1, characterized in that, The attenuation section has a gas collision section that collides with the gas flow of the gas.

15. The substrate processing apparatus according to claim 14, characterized in that, The gas collision section has a deactivation section that deactivates the energy of the gas in the plasma state.

16. The substrate processing apparatus according to claim 1, characterized in that, The attenuation section has an inert gas supply section capable of supplying inert gas to the gas.

17. The substrate processing apparatus according to claim 1, characterized in that, The attenuation section has an ascending section that makes the gas flow direction opposite to the direction of gravity.

18. A substrate processing method, characterized in that, The substrate is processed in the processing chamber using a substrate processing apparatus having the following components: The processing chamber uses gases to process the substrate; A plasma generation unit that sets the gas into a plasma state; A supply pipe is located on the upstream side of the processing chamber; An exhaust pipe is located on the downstream side of the processing chamber; A valve is located on the downstream side of the exhaust pipe; as well as An attenuation section is provided in the exhaust pipe at a position closer to the valve than the processing chamber, or upstream of the connection between the supply pipe and the processing chamber, to attenuate the energy of the gas in the plasma state.

19. A method for manufacturing a semiconductor device, characterized in that, A semiconductor device is manufactured using the substrate processing method of claim 18.

20. A program, characterized in that, Using a substrate processing apparatus having the following components, a computer is used to execute a sequence of processing substrates in a processing chamber: The processing chamber uses gases to process the substrate; A plasma generation unit that sets the gas into a plasma state; A supply pipe is located on the upstream side of the processing chamber; An exhaust pipe is located on the downstream side of the processing chamber; A valve is located on the downstream side of the exhaust pipe; as well as An attenuation section is provided in the exhaust pipe at a position closer to the valve than the processing chamber, or upstream of the connection between the supply pipe and the processing chamber, to attenuate the energy of the gas in the plasma state.

Images