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

Abstract

The present invention comprises: a processing container that accommodates a substrate and processes the substrate; a plasma generation unit that generates plasma in the processing container; a calculation unit that calculates an integrated amount of electrical power output by the plasma generation unit during the processing of the substrate; a storage unit that stores, as a master integrated amount, the integrated amount at the end of the processing when the processing result of the substrate is normal; and a control unit that controls the progress of the processing of the substrate on the basis of a recipe that defines processing conditions including the processing time of the substrate, and can perform control so as to derive a correction time for the processing time from the difference between the calculated integrated amount and the master integrated amount.

Description

Substrate processing apparatus, semiconductor device manufacturing method, and program

[0001] The present disclosure relates to a substrate processing apparatus, a method for manufacturing a semiconductor device, and a program.

[0002] 2. Description of the Related Art As one step in the manufacturing process of a semiconductor device, a process of supplying plasma to a substrate (hereinafter also referred to as plasma processing) may be performed (see, for example, Patent Document 1).

[0003] WO2019 / 082569 publication

[0004] The present disclosure provides a technique that can stabilize the quality of plasma processing performed on a substrate.

[0005] According to one aspect of the present disclosure, there is provided a technology including: a processing vessel for accommodating and processing a substrate; a plasma generation unit for generating plasma within the processing vessel; a calculation unit for calculating an integrated amount of power output by the plasma generation unit during processing of the substrate; a memory unit for storing the integrated amount at the end of processing when the processing result of the substrate is normal as a master integrated amount; and a control unit capable of controlling the progress of processing of the substrate based on a recipe that defines processing conditions including a processing time of the substrate, and calculating a correction time for the processing time from the difference between the calculated integrated amount and the master integrated amount.

[0006] According to the present disclosure, it is possible to stabilize the quality of plasma processing performed on a substrate.

[0007] FIG. 1 is a schematic configuration diagram of a substrate processing apparatus according to an aspect of the present disclosure. FIG. 2 is a schematic configuration diagram of a control unit included in the substrate processing apparatus according to an aspect of the present disclosure. FIG. 3 is a functional block diagram of a substrate processing apparatus that performs a processing time correction sequence according to an aspect of the present disclosure. FIG. 4 is a flow diagram showing a substrate processing sequence according to an aspect of the present disclosure. FIG. 5 is a flow diagram showing a processing time correction sequence according to an aspect of the present disclosure. FIG. 6(a) is a diagram showing an example of control for adjusting a processing time in an increasing direction according to an aspect of the present disclosure. FIG. 6(b) is a diagram showing an example of control for adjusting a processing time in a decreasing direction according to an aspect of the present disclosure. FIG. 6(c) is a diagram showing an example of control for not performing processing time adjustment according to an aspect of the present disclosure. FIG. 7 is a diagram showing an example of a screen output by an input / output unit included in the substrate processing apparatus according to an aspect of the present disclosure.

[0008] <One Aspect of the Present Disclosure> Hereinafter, one aspect of the present disclosure will be described with reference to the drawings. The drawings used in the following description are all schematic, and the dimensional relationships, ratios, etc. of the elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of the elements between multiple drawings do not necessarily match.

[0009] (1) Configuration of Substrate Processing Apparatus First, the configuration of a substrate processing apparatus (hereinafter also referred to as a processing apparatus) 100 will be described with reference to FIGS. 1 to 3 and 7. FIG.

[0010] 1, the processing apparatus 100 includes a processing furnace 202 for processing wafers 200 as substrates. The processing furnace 202 includes a processing vessel 203 for accommodating the wafers 200. The processing vessel 203 includes a dome-shaped upper vessel 210 and a bowl-shaped lower vessel 211. The upper vessel 210 is made of, for example, aluminum oxide (Al ２ O ３ ), quartz (SiO ２ The lower container 211 is made of a non-metallic material such as aluminum (Al), and the lower container 212 is made of a metallic material such as aluminum (Al).

[0011] The processing chamber 201 configured within the processing vessel 203 has a space where plasma is generated (plasma generation space) and a space (substrate processing space) that communicates with the plasma generation space and where the wafers 200 are processed. The plasma generation space is a space within the processing chamber 201 that is surrounded on its outer periphery by a resonant coil 212 (described later). The substrate processing space is a space within the processing chamber 201 that holds the wafers 200 to be processed, and is a space below the plasma generation space.

[0012] An opening 245 and a gate valve 244 that airtightly closes the opening 245 are provided on the lower sidewall of the lower vessel 211. By opening the gate valve 244, a transfer port 245a is opened, and it becomes possible to transfer (load and unload) the wafer 200 into and out of the processing chamber 201.

[0013] (Susceptor) A susceptor 217 is disposed on the bottom side of the processing chamber 201 as a substrate mounting portion for mounting the wafer 200. The susceptor 217 is made of a non-metallic material such as aluminum nitride (AlN), ceramics, or quartz, and is electrically insulated from the lower vessel 211.

[0014] A heater 217b serving as a heating mechanism is provided inside the susceptor 217. A heater power adjustment mechanism 276 is connected to the heater 217b. The heater 217b heats the wafer 200 placed on the susceptor 217 to a predetermined temperature.

[0015] An impedance adjusting electrode 217c is provided inside the susceptor 217. The impedance adjusting electrode 217c is grounded via an impedance variable mechanism 275. The impedance variable mechanism 275 includes a coil and a variable capacitor, and changes the impedance within a range from approximately 0 Ω to the parasitic impedance value of the processing chamber 201 by adjusting at least one of the inductance and resistance of the coil and the capacitance of the variable capacitor. This configuration makes it possible to uniformize the density of the plasma generated above the wafer 200 and to control the potential (bias voltage) of the wafer 200 placed on the susceptor 217.

[0016] An elevating mechanism 268 for raising and lowering the susceptor 217 is provided at the bottom of the processing chamber 201. The susceptor 217 has a through-hole 217a. Pins 266 are provided on the bottom surface of the lower vessel 211. At least three through-holes 217a and three pins 266 are provided at positions facing each other. When the elevating mechanism 268 lowers the susceptor 217, the upper ends of the pins 266 pass through the through-holes 217a and support the wafer 200 from below.

[0017] (Gas Supply Section) A gas supply head 236 that supplies a processing gas into the processing chamber 201 is provided at the top of the upper vessel 210. The gas supply head 236 includes a cap-shaped lid 233, a gas inlet 234, a buffer chamber 237, an opening 238, a shielding plate 240, and a gas outlet 239. The buffer chamber 237 functions as a dispersion space that disperses the processing gas introduced into the processing chamber 201.

[0018] A gas supply pipe 232a for supplying a first process gas, a gas supply pipe 232b for supplying a second process gas, and a gas supply pipe 232c for supplying an inert gas are connected to the gas inlet 234 so that they converge. Gas supply pipes 232a to 232c are respectively provided with gas supply sources 250a to 250c, mass flow controllers (MFCs) 252a to 252c as flow rate control devices, and valves 253a to 253c as on-off valves. A valve 243a is provided in the gas supply pipe 232 formed by the convergence of the gas supply pipes 232a to 232c.

[0019] A first process gas supply system is mainly composed of the gas supply pipe 232a, the MFC 252a, and the valve 253a. The first process gas supply source 250a may also be included in the first process gas supply system. A second process gas supply system is mainly composed of the gas supply pipe 232b, the MFC 252b, and the valve 253b. The second process gas supply source 250b may also be included in the second process gas supply system. An inert gas supply system is mainly composed of the gas supply pipe 232c, the MFC 252c, and the valve 253c. The inert gas supply source 250c may also be included in the inert gas supply system.

[0020] (Exhaust section) An exhaust port 235 is provided on the side wall of the lower container 211. An exhaust pipe 231 is connected to the exhaust port 235. The exhaust pipe 231 is provided with an APC valve 242 as a pressure adjustment section, a valve 243b as an opening / closing valve, and a vacuum pump 246 as an exhaust device. The exhaust port 235, the exhaust pipe 231, the APC valve 242, and the valve 243b mainly constitute the exhaust section. The vacuum pump 246 may be included in the exhaust section.

[0021] (Plasma Generation Unit) A resonant coil 212 wound in a spiral shape is provided on the side of the upper vessel 210 so as to surround the processing chamber 201. An RF sensor 272, a high-frequency power supply 273, and a matching box 274 are connected to the resonant coil 212.

[0022] The high-frequency power supply 273 supplies high-frequency power to the resonant coil 212 via the RF sensor 272. The RF sensor 272 monitors the traveling wave and reflected wave of the high-frequency power supplied from the high-frequency power supply 273 to the resonant coil 212. The matching device 274 controls the power output from the high-frequency power supply 273 to the resonant coil 212. For example, based on information about the reflected wave monitored by the RF sensor 272, the matching device 274 controls the impedance and output frequency of the high-frequency power supply 273 so as to minimize the magnitude of the reflected wave.

[0023] The resonant coil 212 functions as a plasma generating unit that generates standing waves upon receiving power from the high-frequency power supply 273 and generates plasma by creating a predetermined magnetic field in the plasma generation space. The resonant coil 212 has a winding diameter, winding pitch, number of turns, and other settings that allow it to resonate upon receiving power of a predetermined frequency. The resonant coil 212 can receive high-frequency power of, for example, 800 kHz to 50 MHz and 0.1 to 5 kW, and generate a magnetic field of 0.01 to 10 gauss in the plasma generation space. The resonant coil 212 is fixed to the base plate 248 using an insulating member.

[0024] One end of resonance coil 212 is grounded via movable tap 213, and the other end is grounded via fixed tap 214. A movable tap 215 is provided between the grounded ends of resonance coil 212. Movable tap 215 functions as a power supply unit that receives power supply from high frequency power supply 273. By adjusting the connection positions of movable taps 213 and 215 with respect to resonance coil 212, the resonance characteristics of resonance coil 212 can be adapted to the output conditions of high frequency power supply 273.

[0025] A cylindrical shielding plate 223 is disposed on the outer periphery of the resonant coil 212. The shielding plate 223 shields the electric field radiated outward from the resonant coil 212, and also forms a capacitance component (C component), which is one of the components of the resonant circuit, between the shielding plate 223 and the resonant coil 212. The shielding plate 223 is made of a conductive material such as an Al alloy.

[0026] A plasma generation unit (plasma generation section) is mainly configured by the resonant coil 212. The high frequency power supply 273, the RF sensor 272, the matching box 274, the movable taps 213 and 215, and the shielding plate 223 may also be included in the plasma generation unit.

[0027] (Control Unit) The control unit (control means) 221 is configured to control the APC valve 242, the valve 243b, and the vacuum pump 246 via signal line A, the lifting mechanism 268 via signal line B, the heater power adjustment mechanism 276 and the impedance variable mechanism 275 via signal line C, the gate valve 244 via signal line D, the RF sensor 272, the high-frequency power supply 273, and the matching box 274 via signal line E, and the MFCs 252a to 252c, the valves 253a to 253c, and 243a via signal line F.

[0028] As shown in FIG. 2 , the control unit 221 is configured as a computer including a CPU 221a, a RAM 221b, a storage unit 221c, and an I / O port 221d. The RAM 221b, the storage unit 221c, and the I / O port 221d are configured to exchange data with the CPU 221a via an internal bus 221e. An input / output unit 222 configured as, for example, a touch panel is connected to the control unit 221. An external storage device 221t can be connected to the control unit 221. The processing device 100 may be configured to include one or more control units. That is, control for performing the processing sequence described below may be performed using one control unit or multiple control units. The multiple control units may be configured as a control system connected to each other via a wired or wireless communication network, and control for performing the processing sequence described below may be performed by the entire control system. In this specification, the term "control unit" may refer to a single control unit, multiple control units, or a control system configured by multiple control units.

[0029] The storage unit 221c is composed of a flash memory, an HDD, an SSD, etc. Control programs for controlling the operation of the processing apparatus, process recipes describing procedures and conditions for substrate processing (described later), etc., are readably recorded and stored in the storage unit 221c. The process recipe is a combination of procedures for substrate processing (described later) that are executed by the control unit 221 in the processing apparatus 100 to obtain a predetermined result, and functions as a program. Hereinafter, the process recipes, control programs, etc. are collectively referred to simply as programs. The process recipes are also simply referred to as recipes. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 221b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 221a.

[0030] The I / O port 221d is connected to the above-mentioned MFCs 252a to 252c, valves 253a to 253c, 243a, and 243b, the APC valve 242, the vacuum pump 246, the RF sensor 272, the high-frequency power supply 273, the matching box 274, the impedance variable mechanism 275, the heater power adjustment mechanism 276, the gate valve 244, and the lifting mechanism 268.

[0031] The CPU 221a is configured to read and execute a control program from the storage unit 221c, and to read a recipe from the storage unit 221c in response to an input of an operation command from the input / output unit 222. The CPU 221a is configured to control, in accordance with the contents of the read recipe, the flow rate adjustment of various gases by the MFCs 252a to 252c, the opening and closing operations of the valves 253a to 253c, 243a, and 243b, the opening adjustment operation of the APC valve 242, the start and stop of the vacuum pump 246, the power supply operation to the resonance coil 212 by the RF sensor 272, the high-frequency power supply 273, and the matching box 274, the impedance value adjustment operation by the impedance variable mechanism 275, the temperature adjustment operation of the heater 217b by the heater power adjustment mechanism 276, the opening and closing operation of the gate valve 244, the lifting and lowering operation of the susceptor 217 by the lifting mechanism 268, and the like.

[0032] The control unit 221 can be configured by installing the above-mentioned program recorded and stored in the external storage device 221t into a computer. The external storage device 221t includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, a magneto-optical disk such as an MO, and a semiconductor memory such as a USB memory or an SSD. The storage unit 221c and the external storage device 221t are configured as computer-readable recording media. Hereinafter, these will be collectively referred to as recording media. When the term recording medium is used in this specification, it may include only the storage unit 221c, only the external storage device 221t, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 221t.

[0033] The control unit 221 in this embodiment further includes a calculation unit 221f. The calculation unit 221f is configured to be able to exchange data with the CPU 221a, RAM 221b, storage unit 221c, I / O port 221d, etc. via an internal bus 221e of the control unit 221. The calculation unit 221f may be a function realized by predetermined hardware, or may be a function realized by software when the CPU 221a reads and executes a control program from the storage unit 221c. The calculation unit 221f may be configured as one of the components of the control unit 221 as shown in FIG. 2, or may be configured separately from the control unit 221.

[0034] As shown in FIG. 3 , the calculation unit 221f is configured to calculate an integrated amount P of power output by the plasma generating unit based on information acquired by the control unit 221 via the RF sensor 272 during the substrate processing S230 described below. The integrated amount P calculated by the calculation unit 221f may include an integrated amount Pt of the forward wave power output by the plasma generating unit, and may also include an integrated amount Pr of the reflected wave power output by the plasma generating unit. Furthermore, the calculation unit 221f is configured to calculate the integrated amount P in real time or repeatedly at a predetermined interval during the substrate processing S230. Furthermore, the calculation unit 221f is configured not to calculate the integrated amount P during the discharge preparation S210 and discharge ignition S220 described below, but to calculate the integrated amount P during the substrate processing S230.

[0035] Furthermore, as shown in FIG. 3, the memory unit 221c is configured to store the accumulated amount P calculated by the calculation unit 221f at the end of the substrate processing S230 described below when the substrate processing result is normal, so that it can be read out as a master accumulated amount Pm.

[0036] 3, when controlling the progress of substrate processing S230 (described later) based on a recipe that defines processing conditions including processing time T, the control unit 221 is configured to calculate a difference ΔP between the accumulated amount P calculated by the calculation unit 221f during substrate processing S230 and the master accumulated amount Pm stored in the memory unit 221c. The control unit 221 is also configured to calculate a correction time ΔT for the processing time T based on the obtained difference ΔP, and adjust the end timing of the substrate processing S230 based on the correction time ΔT. Note that the processing time in this specification refers to the time the processing continues. These terms also apply to the following explanations.

[0037] Specifically, the control unit 221 is configured to adjust the processing time T in a positive direction based on the correction time ΔT when the cumulative amount P after the processing time T has elapsed is expected to be smaller than the master cumulative amount Pm. Furthermore, the control unit 221 is configured to adjust the processing time T in a negative direction based on the correction time ΔT when the cumulative amount P after the processing time T has elapsed is expected to be larger than the master cumulative amount Pm. Furthermore, the control unit 221 is configured not to adjust the processing time T based on the correction time ΔT when it is expected that there will be no difference between the cumulative amount P after the processing time T has elapsed and the master cumulative amount Pm. The control unit 221 is then configured to continue or stop the substrate processing S230 in accordance with the corrected processing time T.

[0038] 7, the input / output unit 222 is configured to be able to display the waveform Wt of the power of the traveling wave output by the plasma generation unit and the waveform Wr of the power of the reflected wave output by the plasma generation unit based on information acquired by the control unit 221 via the RF sensor 272. Specifically, the input / output unit 222 is configured to display the waveform Wt of the power of the traveling wave output by at least one of the resonant coil 212, the high-frequency power supply 224, and the matching box 274 and the waveform Wr of the power of the reflected wave output by these devices. The input / output unit 222 is also configured to display the power value Mt of the traveling wave and the power value Mr of the reflected wave monitored via the RF sensor 272.

[0039] The input / output unit 222 is also configured to display the integrated amount Pt of the power of the forward wave and the integrated amount Pr of the power of the reflected wave, which are calculated by the calculation unit 221f during the substrate processing S230 described below. Note that the input / output unit 222 can also display an integrated amount P obtained by adding up the integrated amount Pt of the power of the forward wave and the integrated amount Pr of the power of the reflected wave instead of or in addition to these.

[0040] The input / output unit 222 is also configured to display the progress status (recipe step information) S of the substrate processing S230 (described later), the integrated amount P calculated by the calculation unit 221f during the substrate processing S230 (described later), and the master integrated amount Pm read from the storage unit 221c. The integrated amount P is obtained by adding up the integrated amount Pt and the integrated amount Pr, as described above. Figure 7 shows an example in which the integrated amount P is essentially displayed by displaying the integrated amounts Pt and Pr.

[0041] These will be described in detail in the substrate processing steps below.

[0042] (2) Substrate Processing Step An example of a method for processing a substrate as one step in a semiconductor device manufacturing process (manufacturing method) using the processing apparatus 100 described above, i.e., a sequence for processing a wafer 200 as a substrate with plasma, will be described with reference to Figures 4, 5, and 6(a) to 6(c). In the following description, the operation of each part of the processing apparatus 100 is controlled by a control unit 221.

[0043] (Substrate Loading S110) First, the susceptor 217 is lowered by the lifting mechanism 268, and the upper ends of the pins 266 protrude from the upper surface of the susceptor 217. Thereafter, the gate valve 244 is opened, and the wafer 200 is loaded into the processing chamber 201. After the wafer 200 is loaded, the gate valve 244 is closed, and the processing chamber 201 is sealed. Thereafter, the susceptor 217 is raised by the lifting mechanism 268, and the wafer 200 is transferred onto the susceptor 217.

[0044] (Temperature / Pressure Adjustment S120) The temperature of the heater 217b is adjusted using the heater power adjustment mechanism 276, and the temperature of the wafer 200 on the susceptor 217 is set to a predetermined processing temperature (temperature adjustment). In addition, the processing chamber 201 is evacuated by the vacuum pump 246 while adjusting the aperture of the APC valve 242, and the pressure in the processing chamber 201 is set to a predetermined processing pressure (pressure adjustment). These controls continue at least until the plasma processing S140, which will be described later, is completed.

[0045] (Processing Gas Supply S130) The valves 253a and 253b are opened to allow processing gases (first processing gas and second processing gas) to flow into the gas supply pipes 232a and 232b. The flow rates of the processing gases are adjusted by the MFCs 252a and 252b, and the processing gases are supplied into the processing chamber 201 via the gas supply pipe 232 and the gas supply head 236. At this time, the valve 243c may be opened to supply an inert gas into the processing chamber 201 via the gas supply pipe 232 and the gas supply head 236. The supply of the processing gases continues until the plasma processing S140, which will be described later, is completed.

[0046] (Plasma Processing S140) Next, plasma processing S140 is performed. The progress of this processing is controlled based on a recipe including a preparatory recipe that defines preparatory processing including plasma discharge and ignition, a main recipe that defines processing to be performed on the substrate, and a sub-recipe that defines additional processing to be performed on the substrate.

[0047] First, based on the preparation recipe, preparation for plasma ignition by the plasma generation unit is performed (discharge preparation S210). For example, the process waits until the pressure inside the processing chamber 201 reaches a predetermined pressure and stabilizes. Also, for example, preparation for plasma ignition operation is performed by the RF sensor 272, the high-frequency power supply 273, and the matching box 274. Also, for example, an initial value of impedance is set by the impedance variable mechanism 275.

[0048] Thereafter, based on the preparation recipe, high-frequency power is supplied from the high-frequency power supply 273 to the resonant coil 212, and plasma generation by the plasma generation unit begins (discharge ignition S220). This excites plasma (induced plasma) of the processing gas in the plasma generation space within the processing chamber 201, dissociating the plasma-like processing gas molecules and starting to generate reactive species such as various radicals and ions. It takes a certain amount of time for the plasma generated in the plasma generation space to stabilize. During this time, the impedance is adjusted by the impedance variable mechanism 275, and the power output by the plasma generation unit may become unstable.

[0049] Once the generation of plasma in the plasma generating space is stabilized, processing of the wafer 200 is started based on the main recipe (substrate processing S230). In this processing, reactive species contained in the plasma are uniformly and continuously supplied to the surface of the wafer 200, and react with the surface of the wafer 200, thereby processing the surface of the wafer 200. By performing this processing, for example, it is possible to form a film on the surface of the wafer 200 by modifying the surface. For example, if the surface of the wafer 200 to be processed contains silicon (Si), and nitrogen (N ２ ) gas as the second process gas, and ２ When a hydrogen-containing gas such as a silicon nitride (SiN) gas is used, a silicon nitride film (SiN film) having a predetermined thickness is formed on the surface of the wafer 200 .

[0050] The processing conditions for the substrate processing S230 are exemplified below. These information are defined in the main recipe described above. Processing temperature: 150 to 750° C. Processing pressure: 1 to 250 Pa, preferably 1 to 5 Pa Processing time: 1 to 600 seconds, preferably 120 to 300 seconds First processing gas supply flow rate: 0.02 to 5 slm, preferably 0.1 to 1 slm Second processing gas supply flow rate: 0.02 to 5 slm, preferably 0.1 to 1 slm First processing gas supply flow rate / second processing gas supply flow rate: 1 / 10 to 10 / 1 Inert gas supply flow rate: 0 to 10 slm RF power: 1 to 5000 W, preferably 100 to 3500 W RF frequency: 13.5 MHz or 27 MHz

[0051] In this specification, when a numerical range such as "150 to 750°C" is expressed, it means that the lower limit and the upper limit are included in the range. Therefore, for example, "150 to 750°C" means "150°C or higher and 750°C or lower." The same applies to other numerical ranges. Furthermore, the processing temperature refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Furthermore, when the supply flow rate includes 0 slm, 0 slm means that the gas is not supplied. Furthermore, the RF power refers to the high-frequency power output by the plasma generating unit, and the RF frequency refers to the frequency of the high-frequency power output by the plasma generating unit.

[0052] The first processing gas may be, for example, nitrogen (N ２ ) gas, ammonia (NH ３ ), hydrazine (H ２ N ４ As the first process gas, one or more of these gases may be used.

[0053] The second processing gas may be, for example, hydrogen (H ２ ) gas, deuterium (D ２ As the second process gas, one or more of these gases may be used.

[0054] In addition, at least one of the first processing gas and the second processing gas may be, for example, oxygen (O ２ ) gas, ozone (O ３ ) gas, nitrous oxide (N ２ O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO ２ ) gas, carbon dioxide (CO ２ Alternatively, oxygen-containing gases such as fluorine (CO) gas, carbon monoxide (CO) gas, etc. may be used. As the processing gas, one or more of these may be used.

[0055] The inert gas is nitrogen (N ２Inert gases that can be used include rare gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, and xenon (Xe) gas. One or more of these gases can be used as the inert gas.

[0056] Although the substrate processing S230 is performed in this manner, there are problems with its stability, as described below.

[0057] As described above, the substrate processing S230 is started after the plasma generation in the plasma generating space is stabilized, but even after the substrate processing S230 starts, the power output from the plasma generating unit may temporarily fluctuate due to various factors. Figure 7 shows an example of the waveform Wt of the forward wave power output from the plasma generating unit and the waveform Wr of the reflected wave power (solid line: forward wave, dashed line: reflected wave).

[0058] As shown in the waveform of Figure 7, the power of the forward wave output by the plasma generating unit may temporarily decrease or increase. Furthermore, the power of the reflected wave output by the plasma generating unit may temporarily increase, although the power is controlled by the matching unit 274 to minimize its magnitude. These temporary fluctuations in the power output by the plasma generating unit may result in an increase or decrease in the integrated amount of power output by the plasma generating unit per substrate processing S230, i.e., an excess or deficiency in the total amount of reactive species supplied to the wafer 200 per substrate processing S230 (an excess or deficiency in the degree of plasma processing). In this case, the degree of plasma processing on the wafer 200 may deviate from the target degree. As a result, the thickness and quality of the film formed on the surface of the wafer 200 may deviate from the target value.

[0059] However, if the integrated amount of power output by the plasma generating unit is expected to decrease (the power supply for the process will be insufficient), the insufficient amount of plasma processing can be compensated for by adjusting the processing time T in the substrate processing S230 in a positive direction. Also, if the integrated amount of power output by the plasma generating unit is expected to increase (exceed the power supply for the process), the excess amount of plasma processing can be eliminated by adjusting the processing time T in the substrate processing S230 in a negative direction. Therefore, in this embodiment, the integrated amount P of power output by the plasma generating unit is calculated during the substrate processing S230, and the processing time T in the substrate processing S230 is corrected based on the result, thereby adjusting the end timing of the substrate processing S230.

[0060] (Correction Process of Processing Time T) Hereinafter, the correction process of the processing time T in the substrate processing S230 will be specifically described with reference to FIG.

[0061] After the plasma generation in the plasma generating space is stabilized and the substrate processing S230 is started, the calculation unit 221f acquires information on the power of the forward wave output by the plasma generating unit and information on the power of the reflected wave via the RF sensor 272 (S310). The power information is acquired from at least one of the high-frequency power supply 273, the matching box 274, and the resonant coil 212 via the RF sensor 272, etc.

[0062] The calculation unit 221f calculates the integrated amount Pt of the power of the forward wave output by the plasma generating unit based on the acquired power information, and also calculates the integrated amount Pr of the power of the reflected wave output by the plasma generating unit (S320). The acquisition (S310) and integration (S320) of the power information by the calculation unit 221f may be performed in real time after the substrate processing S230 is started, or may be performed repeatedly at a predetermined interval (for example, at intervals of 50 to 200 msec).

[0063] Then, the calculation unit 221f adds up the obtained integrated amount Pt and integrated amount Pr, and sets this sum as the integrated amount P of the power output by the plasma generation unit. The calculation unit 221f passes the integrated amount P obtained by the addition to the control unit 221. Note that, if the influence of fluctuations in the power of the reflected wave on the substrate processing S230 is negligibly small, the integrated amount Pr of the power of the reflected wave may not be included in the addition, and the integrated amount Pt of the power of the forward wave may be included as the integrated amount P, and this may be passed to the control unit 221. Note that, if the influence of fluctuations in the power of the forward wave on the substrate processing S230 is negligibly small, the integrated amount Pt of the power of the forward wave may not be included in the addition, and the integrated amount Pr of the power of the reflected wave may be included as the integrated amount P, and this may be passed to the control unit 221.

[0064] The control unit 221, which has received the cumulative amount P from the calculation unit 221f, reads out the master cumulative amount Pm from the storage unit 221c (S330). The master cumulative amount Pm is the cumulative amount P calculated by the calculation unit 221f at the end of the substrate processing S230 when the result of the substrate processing S230 is normal. In other words, the master cumulative amount Pm is the cumulative amount of power that the plasma generating unit should output when the substrate processing S230 is normally performed, and is neither excessive nor insufficient. The master cumulative amount Pm is stored in the storage unit 221c before the start of the substrate processing S230. When the substrate processing S230 is repeatedly performed, if the result of the previous substrate processing S230 is normal, the cumulative amount P calculated by the calculation unit 221f at the end of the processing can be used as the master cumulative amount Pm.

[0065] Next, the control unit 221 compares the accumulated amount P calculated by the calculation unit 221f during the substrate processing S230 with the master accumulated amount Pm read from the memory unit 221c to determine the difference ΔP therebetween. Then, based on this difference ΔP, a correction time ΔT for correcting the processing time T of the substrate processing S230 is determined (S340). If the accumulated amount P after the processing time T is expected to be smaller than the master accumulated amount Pm, the correction time ΔT is set to add the processing time T. If the accumulated amount P after the processing time T is expected to be larger than the master accumulated amount Pm, the correction time ΔT is set to subtract the processing time T. If the accumulated amount P after the processing time T is expected to be the same as the master accumulated amount Pm, the correction time ΔT is set to not adjust the processing time T.

[0066] Then, the control unit 221 determines whether or not correction of the processing time T is necessary based on the obtained correction time ΔT (S350).

[0067] If it is determined in the correction necessity determination S350 that the processing time T should be corrected (Yes), the control unit 221 corrects the processing time T as follows (S360).

[0068] For example, when the control unit 221 predicts that the accumulated amount P after the processing time T has elapsed will be smaller than the master accumulated amount Pm, it adjusts the processing time T in a direction that increases based on the correction time ΔT. Various control methods are conceivable for this case, but in this embodiment, as shown in FIG. 6A, the main recipe is completed as defined (i.e., with the processing time T unchanged), and then a sub-recipe, whose processing conditions other than the processing time are defined identically to those defined in the main recipe, is executed continuously for a time equivalent to the correction time ΔT. This effectively increases the processing time T (corrected processing time T = processing time T defined in the recipe + correction time ΔT).

[0069] Furthermore, for example, when the control unit 221 predicts that the accumulated amount P after the processing time T has elapsed will be greater than the master accumulated amount Pm, it adjusts the processing time T to decrease it based on the correction time ΔT. Various control methods are conceivable for this case, but in this embodiment, as shown in FIG. 6B , the execution of the main recipe is terminated early (aborted) when the remaining processing time of the main recipe becomes equal to the correction time ΔT, and the sub-recipe is not executed thereafter. This effectively subtracts the processing time T (corrected processing time T = processing time T defined in the recipe - correction time ΔT). Note that not executing the sub-recipe includes setting the processing time of the sub-recipe to zero and simply executing the sub-recipe, i.e., essentially skipping the sub-recipe.

[0070] If it is determined in the correction necessity determination S350 that correction is not to be made (if the answer is No), that is, if it is expected that there is no difference between the accumulated amount P at the time when the processing time T has elapsed and the master accumulated amount Pm, the control unit 221 does not adjust the processing time T based on the correction time ΔT. Various control methods are possible in this case, but in this embodiment, as shown in FIG. 6C, the remaining processing time of the main recipe is completed as defined (i.e., with the processing time T remaining), and the sub-recipe is not executed thereafter. As a result, adjustment of the processing time T is not made (corrected processing time T = processing time T defined in the recipe).

[0071] If it is determined in the correction necessity determination step S350 that correction is not required (No), the adjustment of the processing time T is not performed, and the above-described series of correction processes (S310 to S350) are then performed again.

[0072] By performing the above-described correction process, the control unit 221 can appropriately continue or stop the substrate processing S230 in accordance with the corrected processing time T, thereby appropriately adjusting the end timing of the substrate processing S230. When stopping the substrate processing S230, the supply of high-frequency power from the high-frequency power supply 273 to the resonance coil 212 is stopped, thereby stopping the generation of plasma in the plasma generation space. In addition, the valves 253a and 253b are closed, thereby stopping the supply of processing gas into the processing chamber 201.

[0073] The above-described correction process is preferably performed a predetermined number of times (one or more times, preferably multiple times) during the substrate processing S230. The correction process may be performed repeatedly at regular intervals during the substrate processing S230, or may be performed multiple times at short intervals only near the end of the substrate processing S230.

[0074] Furthermore, as described above, it is preferable that the calculation unit 221f does not calculate the integrated amount P during the discharge preparation S210 or the discharge ignition S220, but calculates the integrated amount P during the substrate processing S230. That is, it is preferable that the calculation unit 221f does not calculate the integrated amount P during the execution of the preparation recipe, but calculates the integrated amount P during the execution of the main recipe. In the discharge ignition S220, the power output by the plasma generation unit may become unstable. Therefore, by excluding the discharge preparation S210 and the discharge ignition S220 from the target period of the power integration process, it is possible to correct the processing time T more accurately.

[0075] 4, after the substrate processing S230 is completed, the plasma processing S140 is considered to be completed, and the valve 243c is opened to supply an inert gas into the processing chamber 201 via the gas supply pipe 232 and the gas supply head 236. This purges the processing chamber 201, and gases and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas, and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

[0076] (Substrate Unloading S160) The elevating mechanism 268 lowers the susceptor 217, causing the upper ends of the pins 266 to protrude from the upper surface of the susceptor 217, and the wafer 200 is transferred onto the pins 266. Thereafter, the gate valve 244 is opened, and the wafer 200 is unloaded from the processing chamber 201. This completes the substrate processing step in this embodiment.

[0077] (3) Effects of this Aspect According to this aspect, one or more of the following effects can be obtained.

[0078] (a) During the substrate processing S230, the difference ΔP between the integrated amount P calculated by the calculation unit 221f and the master integrated amount Pm read from the memory unit 221c is calculated, a correction time ΔT for the processing time T is calculated based on the difference ΔP, and the end timing of the substrate processing is adjusted based on the correction time ΔT. This makes it possible to match the degree of substrate processing using plasma (processing amount) to the target degree (processing amount) even if the integrated amount of power output by the plasma generation unit per substrate processing S230 increases or decreases. As a result, the quality of the plasma processing can be stabilized and the yield can be improved.

[0079] (b) By including the integrated amount Pt of the forward wave power output by the plasma generation unit and the integrated amount Pr of the reflected wave power, the above-mentioned control can be performed accurately, the quality of the plasma processing can be stabilized, and the yield can be improved.

[0080] (c) The calculation unit 221f calculates the integrated amount P in real time or repeatedly at a predetermined cycle (e.g., 50 to 200 msec) during the substrate processing S230, thereby enabling the above-mentioned control to be performed accurately, stabilizing the quality of the plasma processing and improving the yield.

[0081] (d) When the cumulative amount P after the processing time T has elapsed is expected to be smaller than the master cumulative amount Pm, the processing time T can be adjusted in a direction to increase based on the correction time ΔT, thereby enabling the above-described control to be performed accurately. For example, as in this embodiment, when the cumulative amount P when the main recipe is executed as defined is expected to be smaller than the master cumulative amount Pm, the processing time T can be effectively increased by completing the execution of the main recipe as defined and then continuing with the sub-recipe, thereby enabling the above-described control to be performed accurately.

[0082] (e) When the cumulative amount P after the processing time T has elapsed is expected to be greater than the master cumulative amount Pm, the processing time T can be adjusted to subtract it based on the correction time ΔT, thereby enabling the above-described control to be performed accurately. For example, as in this embodiment, when the cumulative amount P when the main recipe is executed as defined is expected to be greater than the master cumulative amount Pm, the execution of the main recipe is terminated when the remaining processing time of the main recipe becomes equal to the correction time ΔT, and the sub-recipe is not executed thereafter, thereby effectively subtracting the processing time T and enabling the above-described control to be performed accurately.

[0083] (f) When it is expected that there will be no difference between the accumulated amount P after the processing time T has elapsed and the master accumulated amount Pm, the adjustment of the processing time T based on the correction time ΔT is not performed, thereby enabling the above-described control to be performed accurately. For example, as in this embodiment, when it is expected that there will be no difference between the accumulated amount P when the main recipe is executed as defined and the master accumulated amount Pm, the execution of the main recipe is completed as defined, and the sub-recipe is not executed thereafter, thereby enabling the adjustment of the processing time T to be not performed, thereby enabling the above-described control to be performed accurately.

[0084] (g) By continuing or stopping the substrate processing S230 in accordance with the corrected processing time T in this way, the above-mentioned control can be performed accurately, the quality of the plasma processing can be stabilized, and the yield can be improved.

[0085] (h) Since the input / output unit 222 displays the waveform Wt of the power of the traveling wave output by the plasma generating unit and the waveform Wr of the power of the reflected wave output by the plasma generating unit, the operator can easily confirm the normal progress of the substrate processing S230. That is, since the input / output unit 222 displays the waveform of the power of the traveling wave output by at least one of the resonant coil 212, the high-frequency power supply 273, and the matching box 274 and the waveform of the power of the reflected wave output by that device, the operator can easily confirm the normal progress of the substrate processing S230.

[0086] (i) Since the input / output unit 222 displays the cumulative amount Pt of the power of the forward wave output by the plasma generation unit and the cumulative amount Pr of the power of the reflected wave output by the plasma generation unit, the operator can easily confirm the normal progress of the substrate processing S230.

[0087] (j) Since the input / output unit 222 displays the progress status S of the substrate processing S230, the accumulated amount P calculated during the substrate processing S230, and the master accumulated amount Pm read from the memory unit 221c, the operator can easily confirm the normal progress of the substrate processing S230.

[0088] (k) By not calculating the cumulative amount P during execution of the preparatory recipe, but calculating the cumulative amount P during execution of the main recipe, the processing time T can be accurately corrected, the quality of the plasma processing can be stabilized, and the yield can be improved.

[0089] <Other Aspects of the Present Disclosure> The above describes specific aspects of the present disclosure. However, the present disclosure is not limited to the above aspects, and various modifications are possible without departing from the spirit of the present disclosure. Below, examples of other aspects of the present disclosure will be described. Unless otherwise specified, the processing procedures and processing conditions in each step of the following other aspects may be the same as the processing procedures and processing conditions in each step of the above-described processing sequence.

[0090] In the above-described embodiment, as an example of the substrate processing S230, a nitrogen-containing gas or a hydrogen-containing gas is used as a processing gas to form a SiN film on a substrate having a Si surface. However, this embodiment is not limited to this. The present disclosure can also be suitably applied to a case where an oxygen-containing gas, a carbon-containing gas, a silicon-containing gas, or a metal element-containing gas is used as a processing gas to form a film other than a SiN film on a substrate. In this case, the same effects as those of the above-described embodiment can be obtained.

[0091] In the above-described embodiment, the substrate processing step S230 is described as using plasma to modify the surface of the substrate to form a film, but this embodiment is not limited to this. For example, the substrate processing step S230 may be configured to deposit a film on the surface of the substrate using plasma. Also, for example, the substrate processing step S230 may be configured to etch the surface of the substrate using plasma. In these cases, the same effects as those of the above-described embodiment can be obtained.

[0092] It is preferable that the recipes used for each process are individually prepared according to the process content and recorded and stored in the memory unit 221c via an electric communication line or the external storage device 123. When starting each process, it is preferable that the CPU 221a appropriately selects an appropriate recipe according to the process content from among the multiple recipes recorded and stored in the memory unit 221c. This enables the processing device to reproducibly form films of various film types, composition ratios, film qualities, and film thicknesses. It also reduces the burden on the operator, allowing each process to be started quickly while avoiding operational errors.

[0093] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the processing device. When modifying a recipe, the modified recipe may be installed in the processing device via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the processing device may be directly modified by operating the input / output unit 122 provided in the existing processing device.

[0094] In the above-described embodiment, a case where a single-wafer processing apparatus that processes one substrate at a time is used has been described. The present disclosure is not limited to the above-described embodiment, and can also be suitably applied to a case where a single-wafer processing apparatus that processes multiple substrates at a time is used, or to a case where a batch processing apparatus that processes multiple substrates at a time is used. Furthermore, in the above-described embodiment, a case where a processing apparatus having a cold-wall processing furnace is used has been described. The present disclosure is not limited to the above-described embodiment, and can also be suitably applied to a case where a processing apparatus having a hot-wall processing furnace is used.

[0095] When using these processing devices, each process can be performed using the same processing procedures and conditions as in the above-described embodiments and modifications, and the same effects as in the above-described embodiments and modifications can be obtained.

[0096] The above-described embodiments and modifications may be used in combination as appropriate. The processing procedures and processing conditions in such a case may be the same as those of the above-described embodiments and modifications, for example.

[0097] REFERENCE SIGNS LIST 100 Substrate processing apparatus 200 Wafer (substrate) 203 Processing container 221 Control unit 221f Calculation unit 221c Storage unit

Claims

1. A substrate processing apparatus comprising: a processing vessel for accommodating and processing a substrate; a plasma generating unit for generating plasma within the processing vessel; a calculation unit for calculating an integrated amount of power output by the plasma generating unit during processing of the substrate; a memory unit for storing the integrated amount at the end of processing when the processing result of the substrate is normal as a master integrated amount; and a control unit capable of controlling the progress of processing of the substrate based on a recipe that defines processing conditions including a processing time for the substrate, and of calculating a correction time for the processing time from the difference between the calculated integrated amount and the master integrated amount.

2. The substrate processing apparatus according to claim 1, wherein the control unit is capable of controlling to adjust a timing for ending processing of the substrate based on the correction time.

3. The substrate processing apparatus according to claim 1, wherein the integrated amount includes an integrated amount of traveling wave power output by the plasma generating unit.

4. The substrate processing apparatus according to claim 1, wherein the integrated amount includes an integrated amount of power of a reflected wave output by the plasma generating unit.

5. The substrate processing apparatus according to claim 1, wherein the calculation section calculates the integrated amount in real time or repeatedly at a predetermined cycle during processing of the substrate.

6. The substrate processing apparatus according to claim 1, wherein the control unit adjusts the processing time in a positive direction based on the correction time when the integrated amount over the processing time is expected to be smaller than the master integrated amount.

7. The substrate processing apparatus according to claim 1, wherein the control unit adjusts the processing time in a subtractive direction based on the correction time when the integrated amount over the processing time is expected to be greater than the master integrated amount.

8. The substrate processing apparatus of claim 1, wherein the control unit does not adjust the processing time based on the correction time when it is expected that there is no difference between the accumulated amount over the elapsed processing time and the master accumulated amount.

9. The substrate processing apparatus according to claim 6 or 7, wherein the control unit continues or stops processing of the substrate in accordance with the corrected processing time.

10. The substrate processing apparatus according to claim 1, further comprising an input / output unit configured to display a waveform of the forward wave power output by the plasma generating unit and a waveform of the reflected wave power output by the plasma generating unit.

11. The substrate processing apparatus according to claim 10, wherein the input / output unit is configured to display an integrated amount of power of the forward wave and an integrated amount of power of the reflected wave.

12. The substrate processing apparatus according to claim 10, wherein the input / output unit is configured to display a progress status of the substrate processing, the integrated amount P calculated during the substrate processing, and the master integrated amount.

13. The substrate processing apparatus according to claim 1, wherein the recipe comprises: a preparation recipe that defines preparation processing including plasma discharge and ignition; a main recipe that defines processing to be performed on the substrate; and a sub-recipe that defines additional processing to be performed on the substrate.

14. The substrate processing apparatus according to claim 13, wherein the calculation unit is configured not to calculate the integrated amount while the preparatory recipe is being executed, but to calculate the integrated amount while the main recipe is being executed.

15. The substrate processing apparatus according to claim 13, wherein the control unit is configured to complete execution of the main recipe as defined and then continue to execute the sub-recipe when it is expected that the accumulated amount when the main recipe is executed as defined will be smaller than the master accumulated amount.

16. The substrate processing apparatus of claim 13, wherein the control unit is configured to terminate execution of the main recipe at a time when the remaining processing time of the main recipe becomes equal to the correction time when the accumulated amount when the main recipe is executed as defined is expected to be greater than the master accumulated amount, and not to execute the sub-recipe thereafter.

17. The substrate processing apparatus of claim 13, wherein the control unit is configured to complete execution of the main recipe as defined when it is expected that there is no difference between the accumulated amount when the main recipe is executed as defined and the master accumulated amount, and to not execute the sub-recipe thereafter.

18. A method for manufacturing a semiconductor device comprising the steps of: generating a plasma in a space containing a substrate; processing the substrate based on a recipe that defines processing conditions including a processing time for the substrate; calculating an integrated amount of power used to generate the plasma during the processing of the substrate; storing the integrated amount at the end of processing when the processing result of the substrate is normal as a master integrated amount; and determining a correction time for the processing time from the difference between the integrated amount calculated during the processing of the substrate and the master integrated amount.

19. The method of manufacturing a semiconductor device according to claim 18, further comprising the step of adjusting a finish timing of the substrate based on the corrected time.

20. A program that causes a substrate processing apparatus to execute, by a computer, the following steps: generating plasma in a space containing a substrate; processing the substrate based on a recipe that defines processing conditions including a processing time for the substrate; calculating an integrated amount of power used to generate the plasma during the processing of the substrate; storing the integrated amount at the end of processing when the processing result of the substrate is normal as a master integrated amount; and calculating a correction time for the processing time from the difference between the integrated amount calculated during the processing of the substrate and the master integrated amount.

21. The program according to claim 20, further comprising the step of adjusting a finish timing of the substrate based on the corrected time.

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