KR20200107762A - Substrate processing apparatus, method of manufacturing semiconductor device and non-transitory computer-readable recording medium - Google Patents

Abstract

Provided is a technique capable of making the film thickness formed on a substrate uniform between batch processes. According to the present invention, a substrate processing apparatus comprises: a processing chamber accommodating a substrate; a heating unit for heating the interior of the processing chamber; a control unit for controlling to be able to form a film on the substrate based on a set process parameter; a calculation unit which calculates the film thickness attached to the processing chamber; and a storage unit which stores an accumulated value of the film thickness calculated by the calculation unit as the accumulated film thickness. The control unit is configured to be able to determine set values other than the temperature of the process parameter according to the accumulated film thickness stored in the storage unit.

Description

BACKGROUND OF THE INVENTION [0002] TECHNICAL FIELD The manufacturing method and recording medium of a substrate processing apparatus, a semiconductor apparatus, and a recording medium TECHNICAL FIELD [SUBSTRATE PROCESSING APPARATUS, METHOD OF MANUFACTURE

The present disclosure relates to a substrate processing apparatus, a method of manufacturing a semiconductor device, and a recording medium.

It is performed to form a film on the substrate by heating the inside of the reaction furnace with a heating device (see, for example, Patent Document 1).

1. Japanese Unexamined Patent Application Publication No. 2003-109906

In the reactor as described above, as the number of batches for performing substrate treatment increases, a film is deposited and accumulated on the inner wall surface of the reactor or a temperature detector installed in the reactor. Depending on the film adhering and accumulated in the reactor, the film thickness of the formed film may vary between batch treatments even if batch treatment is performed with the same set value.

An object of the present disclosure is to provide a technique capable of making the film thickness formed on a substrate uniform between batch processing.

According to one aspect of the present disclosure, there is provided a processing chamber for accommodating a substrate; A heating unit for heating the interior of the processing chamber; A control unit that controls to be able to form a film on the substrate based on the set process parameters; A calculation unit that calculates a film thickness attached to the processing chamber; And a storage unit storing the accumulated film thickness calculated by the calculation unit as the accumulated film thickness, wherein the control unit is capable of determining a set value other than the temperature of the process parameter according to the accumulated film thickness stored in the storage unit. The technology to be constructed is provided.

According to the present disclosure, the thickness of the film formed on the substrate can be made uniform between batch processing.

1 is a longitudinal sectional view schematically showing a vertical processing furnace of a substrate processing apparatus according to an embodiment of the present disclosure.
Fig. 2 is a schematic cross-sectional view along line AA in Fig. 1;
3 is a schematic configuration diagram of a controller of a substrate processing apparatus according to an embodiment of the present disclosure, and a block diagram showing a control system of the controller.
4 is a flowchart showing the operation of the substrate processing apparatus according to the embodiment of the present disclosure.
Fig. 5 is a diagram showing a relationship between a cumulative film thickness in a processing chamber and a film thickness of a film formed on a substrate for each batch process in a comparative example.
6 is a diagram showing an example of data stored in a storage device.
7 is a diagram showing an example of data stored in a storage device.
FIG. 8 is a diagram showing a relationship between a cumulative film thickness in a processing chamber and a film thickness of a film formed on a substrate for each batch process compared with a comparative example in the embodiment of the present disclosure.
9 is a flowchart showing the operation of the substrate processing apparatus in the second embodiment.

<An embodiment of the present disclosure>

Hereinafter, an embodiment of the present disclosure will be described. The substrate processing apparatus 10 is configured as an example of an apparatus used in a manufacturing process of a semiconductor device.

(1) Configuration of substrate processing apparatus

The substrate processing apparatus 10 includes a processing furnace 202 provided with a heater 207 as a heating unit (heating means, heating mechanism, and heating system). The heater 207 has a cylindrical shape and is vertically installed by being supported by a heater base (not shown) as a retaining plate.

Inside the heater 207, an outer tube 203, which is a reaction tube constituting a reaction container (processing container) concentric with the heater 207, is disposed. The outer tube 203 is made of a heat-resistant material such as quartz (SiO ₂ ) and silicon carbide (SiC), and is formed in a cylindrical shape with an upper end closed and an open lower end. A manifold (inlet flange) 209 is disposed below the outer tube 203 in a concentric shape with the outer tube 203. The manifold 209 is made of metal such as stainless steel (SUS), and is formed in a cylindrical shape with open top and bottom. An O-ring 220a as a seal member is provided between the upper end of the manifold 209 and the outer tube 203. The outer tube 203 is installed vertically by supporting the manifold 209 on the heater base.

An inner tube 204 constituting the reaction vessel is disposed inside the outer tube 203. The inner tube 204 is made of, for example, a heat-resistant material such as quartz (SiO ₂ ) and silicon carbide (SiC), and is formed in a cylindrical shape with a closed upper end and an open lower end. Mainly, the outer tube 203, the inner tube 204, and the manifold 209 constitute a processing vessel (reaction vessel). A processing chamber 201 is formed in the hollow portion of the processing container (inside the inner tube 204).

The processing chamber 201 is configured to be accommodated in a state in which the wafers 200 as substrates are arranged in multiple stages in the vertical direction in a horizontal position by a boat 217 to be described later. Further, the inside of the processing chamber 201 is heated by a heater 207.

In the processing chamber 201, the nozzles 410 and 420 are installed so as to penetrate the side wall of the manifold 209 and the inner tube 204. Gas supply pipes 310 and 320 serving as gas supply lines are connected to the nozzles 410 and 420, respectively. In this way, the substrate processing apparatus 10 is provided with two nozzles 410 and 420 and two gas supply pipes 310 and 320, and is configured to supply a plurality of types of gases into the processing chamber 201. However, the processing furnace 202 of this embodiment is not limited to the above-described form.

The gas supply pipes 310 and 320 are provided with mass flow controllers (MFCs) 312 and 322 which are flow controllers (flow controllers) in order from the upstream side. In addition, valves 314 and 324 which are on-off valves are installed in the gas supply pipes 310 and 320, respectively. Gas supply pipes 510 and 520 for supplying an inert gas are connected to the downstream side of the valves 314 and 324 of the gas supply pipes 310 and 320, respectively. The gas supply pipes 510 and 520 are provided with MFCs 512 and 522 as flow controllers (flow controllers) and valves 514 and 524 as opening and closing valves in order from the upstream side.

Nozzles 410 and 420 are connected to each other at the tip ends of the gas supply pipes 310 and 320. The nozzles 410 and 420 are configured as L-shaped nozzles, and a horizontal portion thereof is installed to penetrate the side wall of the manifold 209 and the inner tube 204. The vertical portions of the nozzles 410 and 420 protrude outward in the radial direction of the inner tube 204 and are installed in the inside of the reserve chamber 201a of the channel shape (groove shape) formed to extend in the vertical direction. , In the spare chamber 201a, it is installed along the inner wall of the inner tube 204 toward the upper side (above the arrangement direction of the wafer 200).

The nozzles 410 and 420 are installed so as to extend from the lower area of the processing chamber 201 to the upper area of the processing chamber 201, and a plurality of gas supply holes 410a and 420a are installed at positions opposite to the wafer 200, respectively. do. Accordingly, the processing gas is supplied to the wafer 200 from the gas supply holes 410a and 420a of the nozzles 410 and 420, respectively. A plurality of the gas supply holes 410a and 420a are provided from the lower part to the upper part of the inner tube 204, each having the same opening area, and provided with the same opening pitch. However, the gas supply holes 410a and 420a are not limited to the shape described above. For example, the opening area of the inner tube 204 may be gradually increased from the bottom to the top. Thereby, it becomes possible to make the flow rate of the gas supplied from the gas supply holes 410a and 420a more uniform.

A plurality of gas supply holes 410a and 420a of the nozzles 410 and 420 are installed at a position of a height from the bottom to the top of the boat 217 to be described later. Therefore, the processing gas supplied into the processing chamber 201 from the gas supply holes 410a and 420a of the nozzles 410 and 420 is the wafer 200 accommodated from the bottom to the top of the boat 217, that is, the boat 217. It is supplied to all areas of the wafer 200. The nozzles 410 and 420 may be installed so as to extend from the lower region to the upper region of the processing chamber 201, but are preferably installed to extend to the vicinity of the ceiling of the boat 217.

From the gas supply pipe 310, a raw material gas (metal-containing gas, raw material gas) containing a metal element as a processing gas is supplied into the processing chamber 201 via the MFC 312, the valve 314, and the nozzle 410. . As the raw material, for example, titanium (Ti) as a metal element is included, and titanium tetrachloride (TiCl ₄ ) as a halogen-based raw material (also referred to as a halide or halogen-based titanium raw material) is used.

A reactive gas as a processing gas is supplied from the gas supply pipe 320 into the processing chamber 201 via the MFC 322, the valve 324, and the nozzle 420. As the reaction gas, for example, ammonia (NH ₃ ) gas as an N-containing gas containing nitrogen (N) can be used. NH ₃ acts as a nitriding/reducing agent (nitriding/reducing gas).

As an inert gas from the gas supply pipes 510 and 520, for example, nitrogen (N ₂ ) gas is supplied into the processing chamber 201 via the MFCs 512 and 522, valves 514 and 524, and nozzles 410 and 420, respectively. do. Further, an example of using N ₂ gas as the inert gas will be described below, but in addition to the N ₂ gas as the inert gas, for example, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas, etc. You can also use rare gas.

The processing gas supply system is mainly composed of the gas supply pipes 310 and 320, the MFCs 312 and 322, the valves 314 and 324, and the nozzles 410 and 420, but only the nozzles 410 and 420 are referred to as the processing gas supply system. You can think about it. The process gas supply system may be called a simple gas supply system. When the raw material gas flows from the gas supply pipe 310, the raw material gas supply system is mainly constituted by the gas supply pipe 310, the MFC 312, and the valve 314, but it is considered by including the nozzle 410 in the raw material gas supply system. Also good. In addition, the raw material gas supply system may also be called a raw material supply system. When a metal-containing raw material gas is used as the raw material gas, the raw material gas supply system may also be referred to as a metal-containing raw material gas supply system. In the case of flowing the reactive gas from the gas supply pipe 320, the reaction gas supply system is mainly constituted by the gas supply pipe 320, the MFC 322, and the valve 324, but the nozzle 420 is considered to be included in the reactive gas supply system. Also good. When a nitrogen-containing gas is supplied as a reactive gas from the gas supply pipe 320, the reactive gas supply system may also be referred to as a nitrogen-containing gas supply system. Further, an inert gas supply system is mainly constituted by gas supply pipes 510 and 520, MFCs 512 and 522, and valves 514 and 524. The inert gas supply system may also be referred to as a purge gas supply system, a dilution gas supply system, or a carrier gas supply system.

The gas supply method in this embodiment is in a cylindrically long space defined by the inner wall of the inner tube 204 and the end of the plurality of wafers 200, that is, in a cylindrical space. Gas is conveyed via the nozzles 410 and 420 arranged in the spare chamber 201a. Then, gas is blown into the inner tube 204 from the plurality of gas supply holes 410a and 420a provided at positions opposite to the wafers of the nozzles 410 and 420. More specifically, the gas supply hole 410a of the nozzle 410 and the gas supply hole 420a of the nozzle 420 are used to eject the raw material gas in a direction parallel to the surface of the wafer 200, that is, in a horizontal direction. .

The exhaust hole (exhaust port) 204a is a side wall of the inner tube 204 and is a through hole formed at a position opposite to the nozzles 410 and 420, that is, at a position 180° opposite to the spare chamber 201a, for example, in a vertical direction. It is a through hole in the shape of a slit that is elongated and opened. Therefore, the gas supplied into the processing chamber 201 from the gas supply holes 410a and 420a of the nozzles 410 and 420, and the gas flowing on the surface of the wafer 200, that is, the remaining gas (residual gas), is the exhaust hole 204a ) Flows in the exhaust passage 206 formed of a gap formed between the inner tube 204 and the outer tube 203. Then, the gas flowing in the exhaust path 206 flows into the exhaust pipe 231 and is discharged to the outside of the processing furnace 202.

The exhaust hole 204a is installed at a position facing the plurality of wafers 200 (preferably a position facing the lower portion from the top of the boat 217), and the processing chamber 201 from the gas supply holes 410a and 420a The gas supplied to the vicinity of the inner wafer 200 flows in a horizontal direction, that is, in a direction parallel to the surface of the wafer 200, and then flows into the exhaust path 206 through the exhaust hole 204a. That is, the gas remaining in the processing chamber 201 is exhausted in parallel with respect to the main surface of the wafer 200 through the exhaust hole 204a. Further, the exhaust hole 204a is not limited to the case where it is configured as a slit-shaped through hole, and may be configured by a plurality of holes.

The manifold 209 is provided with an exhaust pipe 231 that exhausts the atmosphere in the processing chamber 201. In the exhaust pipe 231, a pressure sensor 245 as a pressure detector (pressure detection unit) that detects the pressure in the processing chamber 201 sequentially from the upstream side, an APC (Auto Pressure Controller) valve 243, and a vacuum pump ( 246) is connected. The APC valve 243 can perform vacuum evacuation and vacuum evacuation stop in the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operated, and in a state where the vacuum pump 246 is operated. The pressure in the processing chamber 201 can be adjusted by adjusting the valve opening degree. Mainly, an exhaust system, that is, an exhaust line, is constituted by an exhaust hole 204a, an exhaust path 206, an exhaust pipe 231, an APC valve 243, and a pressure sensor 245. Further, the vacuum pump 246 may be included in the exhaust system.

Below the manifold 209, a seal cap 219 is provided as an individual furnace opening capable of sealing the lower end opening of the manifold 209 hermetically. The seal cap 219 is configured to abut the lower end of the manifold 209 from the lower side in the vertical direction. The seal cap 219 is made of a metal such as SUS, and is formed in a disk shape. On the upper surface of the seal cap 219, an O-ring 220b as a seal member contacting the lower end of the manifold 209 is provided. A rotation mechanism 267 for rotating the boat 217 accommodating the wafer 200 is installed on the side opposite to the processing chamber 201 in the seal cap 219. The rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be elevated in the vertical direction by a boat elevator 115 as an elevating mechanism installed vertically outside the outer tube 203. The boat elevator 115 is configured to be able to carry the boat 217 into and out of the processing chamber 201 by raising and lowering the seal cap 219. The boat elevator 115 is configured as a conveying device (a conveying mechanism) that conveys the boat 217 and the wafer 200 accommodated in the boat 217 into and out of the processing chamber 201.

The boat 217 as a substrate support is arranged to support in multiple stages by aligning a plurality of wafers 200, such as 25 to 200 wafers 200 in a horizontal position and in a state centered with each other, in a multistage manner, that is, arranged at intervals. Is composed. The boat 217 is made of, for example, a heat-resistant material such as quartz or SiC. Under the boat 217, a heat insulating plate 218 made of a heat-resistant material such as quartz or SiC is supported in multiple stages (not shown) in a horizontal position. This configuration makes it difficult for heat from the heater 207 to be transmitted to the seal cap 219 side. However, this embodiment is not limited to the above-described form. For example, the heat insulating plate 218 may not be provided under the boat 217, but a heat insulating cylinder configured as a cylindrical member made of a heat-resistant material such as quartz or SiC may be provided.

As shown in Fig. 2, a temperature sensor 263 as a temperature detector is installed in the inner tube 204, and the amount of energization to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263. As a result, the temperature in the processing chamber 201 is configured to have a desired temperature distribution. Like the nozzles 410 and 420, the temperature sensor 263 has an L shape and is installed along the inner wall of the inner tube 204.

As shown in Fig. 3, the controller 121 serving as a control unit (control unit) includes a CPU (Central Processing Unit) 121a as an operation unit (calculation unit), a random access memory (RAM) 121b, and a storage unit 121c serving as a storage unit. ), and an I/O port 121d. The RAM 121b, the storage device 121c, and the I/O port 121d are configured to be capable of exchanging data with the CPU 121a via an internal bus. An input/output device 122 configured as, for example, a touch panel or the like is connected to the controller 121.

The storage device 121c is composed of, for example, a flash memory, a hard disk drive (HDD), or the like. In the memory device 121c, a control program for controlling the operation of the substrate processing device, a process recipe describing the procedure and conditions of a method for manufacturing a semiconductor device described later, and the like are stored so as to be readable. The process recipe is a combination so that the controller 121 executes each step (each step) in the semiconductor device manufacturing method described later to obtain a predetermined result, and functions as a program. Hereinafter, this process recipe, control program, etc. are collectively referred to as simply a program. In the present specification, when the word program is used, only a single process recipe is included, only a single control program is included, or a combination of a process recipe and a control program may be included. The RAM 121b is configured as a memory area (work area) in which programs, data, etc. read by the CPU 121a are temporarily held.

The I/O port 121d includes the aforementioned MFCs 312, 322, 512, 522, valves 314, 324, 514, 524, pressure sensor 245, APC valve 243, vacuum pump 246, It is connected to a heater 207, a temperature sensor 263, a rotating mechanism 267, a boat elevator 115, and the like.

The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe or the like from the storage device 121c in response to input of an operation command from the input/output device 122 or the like. The CPU 121a is operated to adjust the flow rate of various gases by the MFCs 312, 322, 512, 522 so as to follow the contents of the read recipe, open and close the valves 314, 324, 514, 524, and the APC valve 243. ) Opening and closing operation and pressure adjustment operation based on the pressure sensor 245 by the APC valve 243, temperature adjustment operation of the heater 207 based on the temperature sensor 263, and the start and stop of the vacuum pump 246 , Controls the rotation and rotation speed adjustment operation of the boat 217 by the rotation mechanism 267, the lifting operation of the boat 217 by the boat elevator 115, the receiving operation of the wafer 200 into the boat 217, etc. Is configured to In addition, it is configured to be able to calculate a film thickness described later, a cumulative value (cumulative film thickness) of the film thickness, and a calculation formula for determining a process parameter according to the accumulated film thickness in the processing chamber.

The controller 121 is an external storage device (for example, a magnetic tape, a magnetic disk such as a flexible disk or a hard disk, an optical disk such as CD or DVD, a magneto-optical disk such as MO, a USB memory or a memory card. It can be configured by installing the above-described program stored in the semiconductor memory, etc.] 123 on a computer. The storage device 121c or the external storage device 123 is configured as a computer-readable recording medium. Hereinafter, these are collectively referred to simply as a recording medium. In the present specification, the recording medium may include only the storage device 121c alone, the external storage device 123 alone, or both. Further, the provision of the program to the computer may be performed using a communication means such as the Internet or a dedicated line without using the external storage device 123.

(2) Substrate treatment process (film formation process)

An example of a step of forming a metal film constituting, for example, a gate electrode on the wafer 200 as a step in the manufacturing step of a semiconductor device (device) will be described with reference to FIG. 4. The process of forming the metal film is performed using the processing furnace 202 of the substrate processing apparatus 10 described above. In the following description, the operation of each unit constituting the substrate processing apparatus 10 is controlled by the controller 121. In addition, a series of processing shown in Fig. 4 is a batch processing.

In addition, when the word ``wafer'' is used in this specification, it means ``wafer itself'' or ``a laminate (aggregate) of a wafer and a predetermined layer or film formed on its surface'' (i.e. There is a case where a predetermined layer or film formed on the surface is included and is referred to as a wafer). In addition, when the word ``the surface of the wafer'' is used in this specification, it means ``the surface of the wafer itself (exposed surface),'' or ``the surface of a predetermined layer or film formed on the wafer, that is, as a laminate. In some cases, it means the outermost surface of a wafer. In addition, the use of the word “substrate” in the present specification has the same meaning as when the word “wafer” is used.

(Wafer brought in)

When a plurality of wafers 200 are loaded on the boat 217 (wafer charge), the boat 217 supporting the plurality of wafers 200 as shown in FIG. 1 is a boat elevator 115 ), and carried into the processing chamber 201 (boat load). In this state, the seal cap 219 is in a state in which the lower opening of the outer tube 203 is closed through the O-ring 220.

(Pressure adjustment and temperature adjustment)

The processing chamber 201 is evacuated by the vacuum pump 246 so that the desired pressure (vacuum degree) is reached. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 243 is feedback-controlled (pressure adjustment) based on the measured pressure information. The vacuum pump 246 maintains a state of being operated at all times until at least processing of the wafer 200 is completed. In addition, the processing chamber 201 is heated by the heater 207 so as to reach a desired temperature. At this time, the amount of energization to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so as to obtain a desired temperature distribution within the processing chamber 201 (temperature adjustment). The heating in the processing chamber 201 by the heater 207 is continuously performed for at least until the processing of the wafer 200 is completed.

[TiN film formation process]

Subsequently, a step of forming a TiN film which is a metal nitride film as a metal film, for example, is executed.

[TiCl ₄ gas supply step (S10)]

The valve 314 is opened, and TiCl ₄ gas, which is a source gas, flows into the gas supply pipe 310. The TiCl ₄ gas is flow rate adjusted by the MFC 312, is supplied into the processing chamber 201 from the gas supply hole 410a of the nozzle 410, and is exhausted from the exhaust pipe 231. At this time, TiCl ₄ gas is supplied to the wafer 200. At this time, the valve 514 is simultaneously opened and an inert gas such as N ₂ gas flows into the gas supply pipe 510. The N ₂ gas flowing in the gas supply pipe 510 is adjusted in flow rate by the MFC 512, is supplied into the processing chamber 201 together with the TiCl ₄ gas, and is exhausted from the exhaust pipe 231. In addition, in order to prevent the TiCl ₄ gas from entering the nozzle 420 at this time, the valve 524 is opened and the N ₂ gas flows into the gas supply pipe 520. The N ₂ gas is supplied into the processing chamber 201 through the gas supply pipe 320 and the nozzle 420, and is exhausted from the exhaust pipe 231.

At this time, the APC valve 243 is adjusted so that the pressure in the processing chamber 201 is set to a pressure within the range of 0.1 Pa to 6,650 Pa, for example. The supply flow rate of the TiCl ₄ gas controlled by the MFC 312 is, for example, a flow rate within the range of 0.1 slm to 2 slm. The supply flow rates of the N ₂ gas controlled by the MFCs 512 and 522 are, for example, flow rates within the range of 0.1 slm to 30 slm. The time for supplying the TiCl ₄ gas to the wafer 200 is, for example, a time within the range of 0.01 seconds to 20 seconds. At this time, the temperature of the heater 207 is set to a temperature at which the temperature of the wafer 200 can be, for example, in the range of 250 to 550°C.

Gas flowing in the processing chamber 201 is only TiCl ₄ gas and N ₂ gas, and by supplying TiCl ₄ gas, on the wafer 200 (the underlying film on the surface), for example, less than 1 atomic layer to several atomic layers. A Ti-containing layer of about a thickness is formed. The Ti-containing layer may be a Ti layer containing Cl, an adsorption layer of TiCl ₄ , or both of them. Here, a layer having a thickness of less than one atomic layer means an atomic layer that is formed discontinuously, and a layer having a thickness of one atomic layer means an atomic layer that is continuously formed. This point is also the same for an example described later.

[Residual gas removal step (S11)]

After the Ti-containing layer is formed, the valve 314 is closed and the supply of TiCl ₄ gas is stopped. At this time, the APC valve 243 of the exhaust pipe 231 is opened, and the inside of the processing chamber 201 is evacuated by the vacuum pump 246, and TiCl after contributing to the formation of an unreacted or Ti-containing layer remaining in the processing chamber 201 ₄ Gas is removed from the inside of the processing chamber 201. At this time, the valves 514 and 524 are kept open to maintain the supply of the N ₂ gas into the processing chamber 201. The N ₂ gas acts as a purge gas, and the effect of removing the unreacted TiCl ₄ gas remaining in the processing chamber 201 or after contributing to formation of the Ti-containing layer from the processing chamber 201 can be enhanced.

[NH ₃ gas supply step (S12)]

After removing the residual gas in the processing chamber 201, the valve 324 is opened and the N-containing gas, NH ₃ gas, as a reactive gas flows into the gas supply pipe 320. The NH ₃ gas is supplied into the processing chamber 201 from the gas supply hole 420a of the nozzle 420 by adjusting the flow rate by the MFC 322 and exhausted from the exhaust pipe 231. At this time, NH ₃ gas is supplied to the wafer 200. At this time, the valve 524 is opened and the N ₂ gas flows into the gas supply pipe 520 at the same time. The flow rate of the N ₂ gas flowing through the gas supply pipe 520 is adjusted by the MFC 522. The N ₂ gas is supplied into the processing chamber 201 together with the NH ₃ gas, and is exhausted from the exhaust pipe 231. At this time, in order to prevent the NH ₃ gas from entering the nozzle 410, the valve 514 is opened and the N ₂ gas flows into the gas supply pipe 510. The N ₂ gas is supplied into the processing chamber 201 via the gas supply pipe 310 and the nozzle 410, and is exhausted from the exhaust pipe 231.

When the NH ₃ gas flows, the APC valve 243 is adjusted to adjust the pressure in the processing chamber 201 to a pressure within the range of 0.1 Pa to 6,650 Pa, for example. The supply flow rate of the NH ₃ gas controlled by the MFC 322 is, for example, a flow rate within the range of 0.1 slm to 20 slm. The supply flow rates of the N ₂ gas controlled by the MFCs 512 and 522 are, for example, flow rates within the range of 0.1 slm to 30 slm. The time for supplying the NH ₃ gas to the wafer 200 is, for example, within the range of 0.01 seconds to 30 seconds. The temperature of the heater 207 at this time is set to the same temperature as the TiCl ₄ gas supply step.

At this time, the gas flowing in the processing chamber 201 is only NH ₃ gas and N ₂ gas. The NH ₃ gas reacts with at least a portion of the Ti-containing layer formed on the wafer 200 in the TiCl ₄ gas supply step. During the substitution reaction, Ti included in the Ti-containing layer and N included in the NH ₃ gas are combined, and a TiN layer including Ti and N is formed on the wafer 200.

[Residual gas removal step (S13)]

After forming the TiN layer, the valve 324 is closed and the supply of the NH ₃ gas is stopped. Then, the unreacted NH ₃ gas or reaction by-products remaining in the processing chamber 201 or after contributing to the formation of the TiN layer remaining in the processing chamber 201 are removed from the processing chamber 201 by the same processing procedure as in step S11.

(Conduct a predetermined number of times)

A predetermined thickness (for example, 0.1 nm to 2 nm) on the wafer 200 is performed by performing one or more cycles [a predetermined number of times (n times)] in order of performing the above-described steps S10 to S13. A TiN film is formed. The above-described cycle is a plurality of times, for example, it is preferable to repeat about 200 times. Here, as in the above-described cycle, the number of times one cycle is repeated is the number of cycles.

(After purge and atmospheric pressure return)

N ₂ gas is supplied into the processing chamber 201 from each of the gas supply pipes 510 and 520, and exhausted from the exhaust pipe 231. The N ₂ gas acts as a purge gas, whereby the inside of the processing chamber 201 is purged with an inert gas, and gas and by-products remaining in the processing chamber 201 are removed from the inside of the processing chamber 201 (after purge). After that, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas substitution), and the pressure in the processing chamber 201 is returned to normal pressure (atmospheric pressure is restored).

(Export wafer)

After that, the seal cap 219 is lowered by the boat elevator 115 and the lower end of the outer tube 203 is opened. Then, the processed wafer 200 is carried out to the outside of the outer tube 203 from the lower end of the outer tube 203 in a state supported by the boat 217 (boat unloaded). After that, the processed wafer 200 is taken out from the boat 217 (wafer discharge).

(3) Parameter control of the controller 121

Next, parameter control of the controller 121 in this embodiment will be described.

5 is a comparative example, the cumulative film thickness adhered and accumulated in the processing chamber 201 when the batch processing is performed multiple times with constant process parameters such as the film forming temperature and the number of cycles (hereinafter referred to as the cumulative film thickness in the processing chamber. ) And the thickness of the TiN film formed on the wafer 200 for each batch process. Here, the cumulative film thickness in the processing chamber is an accumulated value of the film thickness of the film formed on the wafer 200 for each batch process.

Specifically, as shown in FIG. 5, a cycle in which a 5 nm TiN film can be formed is performed using a reaction vessel in which a 10 nm coating film is formed in advance in the processing chamber 201 and the number of cycles in one batch is 200 cycles, When the cumulative film thickness in the processing chamber of the first to sixth batch processing is 35 nm or less and the cumulative film thickness in the processing chamber is thin, the film thickness of the TiN film formed on the wafer 200 increases every time the number of batch processing increases (processing chamber Whenever my accumulated film thickness increases), it increases (film thickness riser). This is because a TiN film is attached to the inner wall surface of the inner tube 204 inside the processing chamber 201 or the temperature sensor 263, and the transmittance of radiant heat from the heater 207 decreases as the accumulated film thickness of the attached TiN film increases. This is because the energy transfer to the temperature sensor 263 in the processing chamber 201 is delayed, and as a result, the amount of temperature overshoot changes, and the temperature at the start of the next batch processing is increased.

The effect of the generated temperature overshoot can be tolerated in a recipe in which the temperature stabilization time is set sufficiently long, but in a recipe in which productivity is emphasized and the temperature stabilization time is set short, a change in the film thickness between batch processing occurs.

In addition, as shown in FIG. 5, when the accumulated film thickness in the processing chamber of the 7th batch treatment becomes thicker than 40 nm and reaches a certain thickness, the film thickness of the TiN film formed on the wafer 200 increases. It does not increase each time and stabilizes (film thickness stabilizer). This is because the transmittance of radiant heat from the heater 207 becomes constant regardless of the cumulative film thickness in the processing chamber, and the amount of temperature overshoot becomes constant without changing because the cumulative film thickness in the processing chamber reaches a certain predetermined thickness. That is, when the accumulated film thickness in the processing chamber reaches a certain predetermined film thickness, the film thickness of the film formed on the wafer is also stabilized.

Here, after maintenance, such as dry cleaning, a coating film having a sufficient thickness may be formed in the processing chamber 201 before starting the batch treatment, but in a process with a slow film formation rate such as a TiN film, it takes time to form a coating film having a sufficient thickness. Because it takes, the downtime of the device is long. In addition, when a coating film having a sufficient thickness is formed, the period up to the maintenance limit film thickness such as dry cleaning is shortened, and the production contribution time is shortened. In other words, it is not practical because productivity is remarkably lost.

Therefore, in this embodiment, process parameters such as the number of cycles according to the accumulated film thickness in the processing chamber at the start of a batch processing (at the start of RUN) are determined, and the batch processing is performed using the determined process parameters. Run.

Specifically, the accumulated film thickness in the processing chamber is calculated by sequentially adding the film thicknesses of films formed on the wafer for each batch process. And the accumulated value of the film thickness calculated by adding is stored in the storage device 121c as the accumulated film thickness in the processing chamber.

Specifically, by using a reaction vessel in which a 10 nm coating film is formed in advance in the processing chamber 201, the number of cycles in one batch processing is 200 cycles, and a cycle in which a 5 nm TiN film can be formed is performed, the processing chamber of the first batch processing The internal cumulative film thickness is 10 nm, the cumulative film thickness in the processing chamber of the second batch processing is 15 nm, the cumulative film thickness in the processing chamber of the third batch processing is 20 nm, and so on, the CPU 121a is the same as the film thickness formed per batch processing. The accumulated value is calculated, and the calculated accumulated value is stored in the storage device 121c as the accumulated film thickness in the processing chamber.

Further, for example, a correction table of the number of cycles per process recipe as shown in Fig. 6 is stored in advance in the memory device 121c. That is, the number of cycles, which is an example of the process parameter determined according to the accumulated film thickness in the processing chamber, is stored in the storage device 121c for each process recipe.

In the case of forming a film type in which the film thickness of the film formed on the wafer 200 increases as the cumulative film thickness in the processing chamber increases as in this embodiment, the number of cycles increases as the accumulated film thickness in the processing chamber increases as shown in FIG. Use the same correction table to reduce In addition, instead of a correction table, a calculation formula for determining a process parameter according to the accumulated film thickness in the processing chamber may be stored in the storage device 121c for each process recipe. That is, the number of cycles is determined according to the set film thickness formed on the wafer 200 of the process recipe, and the number of cycles is changed according to the accumulated film thickness in the processing chamber. Further, the number of cycles may be determined according to the gas supply time.

Further, for example, a correction table of the film formation rate for each process recipe as shown in Fig. 7 is stored in advance in the storage device 121c. That is, the film formation rate according to the processing temperature is stored in the storage device 121c for each process recipe. That is, the film formation rate according to the processing temperature is determined according to the process recipe, and the film thickness for each cycle is determined.

Specifically, for example, if the film formation rate of the TiN film at a treatment temperature of less than 380°C is set to 0.025 nm/cycle, a 5 nm TiN film is formed by repeating 200 cycles of one batch treatment. Further, if the film formation rate at a treatment temperature of 380°C or more and less than 480°C is set to 0.035 nm/cycle, a 7 nm TiN film is formed by repeating 200 cycles of one batch treatment. Further, if the film formation rate at 480°C or higher and lower than 580°C is set to 0.045 nm/cycle, a 9 nm TiN film is formed by repeating 200 cycles of one batch process.

That is, by storing the film formation rate according to the processing temperature as shown in FIG. 7 in the memory device 121c, the accumulated film thickness in the processing chamber can be calculated, and the process parameter can also be changed according to the accumulated film thickness in the processing chamber. In addition, there are cases where ±0.05nm and ±50°C change depending on the device environment such as disturbance.

That is, at the start of the batch process, the controller 121 determines set values of process parameters such as the number of cycles using a correction table or a calculation formula prepared in advance as shown in Figs. 6 or 7.

That is, the controller 121 determines the set value of the process parameter according to the accumulated film thickness in the processing chamber for each batch process. Then, the TiN film is formed on the wafer 200 using process parameters such as the number of cycles determined according to the accumulated film thickness in the processing chamber.

Specifically, in a region with a thin cumulative film thickness in the processing chamber as shown in FIG. 5 (film thickness increase device), by setting a large number of cycles, the film thickness of the TiN film formed on the wafer is reduced to the thickness stabilizer and It is corrected to have the same film thickness.

That is, as shown in Fig. 8, in the region where the accumulated film thickness in the processing chamber after maintenance such as dry cleaning is thin, the number of cycles is set and the number of cycles is reduced as the accumulated film thickness in the processing chamber increases. The film thickness of the TiN film to be used can be corrected so that the same film thickness as the film thickness stabilizer is formed.

That is, the controller 121 determines process parameters such as the number of cycles according to the accumulated film thickness in the processing chamber at the start of the batch processing at the start of the batch processing, and executes the batch processing using the determined process parameters. The film formed on 200) can be made uniform between batch processing.

(4) Effects according to this embodiment

According to this embodiment, one or more effects shown below can be obtained.

(a) The film thickness formed on the substrate can be made uniform between batch processing.

(b) By automatically adding the accumulated film thickness in the processing chamber and automatically switching the process parameters for each accumulated film thickness, it is possible to shorten the processing time and reduce the risk of defective production due to human error.

<2nd embodiment>

Next, a second embodiment will be described with reference to FIG. 9.

In the second embodiment, for example, a tungsten (W) film is formed as a metal film on the TiN film formed on the wafer 200 in the above-described embodiment. In the second embodiment, a WF ₆ gas supply system that supplies tungsten hexafluoride (WF ₆ ) gas into the processing chamber 201 of the substrate processing apparatus 10 described above, and a hydrogen (H ₂ ) gas supply into the processing chamber 201 Install the H ₂ gas supply system. And as shown in Fig. 9, in the same processing furnace 202, a cycle of sequentially performing steps S10 to S13, which is the above-described TiN film formation process, is performed once or more (a predetermined number of times (n times)). After performing, WF ₆ gas supply (step S20), residual gas removal (step S21), H ₂ gas supply (step S22), residual gas removal (step S23), which are W film formation steps 1 or more cycles in order [a predetermined number of times (m times)], and at least one cycle in which steps (S10) to (S13) and steps (S20) to (S23) are performed in order Execute [prescribed number of times (p times)]. In the present embodiment, the series of processing shown in Fig. 9 is one batch processing, and one batch processing includes two cycles of a TiN film forming step and a W film forming step.

In the second embodiment, the correction table in each cycle of the TiN film formation process and the W film formation process is stored in the storage device 121c. At the start of each cycle, process parameters such as the number of cycles are determined according to the accumulated film thickness in the processing chamber. That is, one batch process is performed using process parameters such as the number of cycles according to the accumulated film thickness in the processing chamber in the TiN film formation process, and the process parameters such as the number of cycles according to the accumulated film thickness in the processing chamber in the W film forming process. . Also in this embodiment, the same effect as the above-described embodiment can be obtained.

In other words, even in the case of executing a process recipe including a plurality of cycles, as in the above-described embodiment, process parameters such as the number of cycles according to the accumulated film thickness are determined for each cycle, and batch processing is performed, similar to the above-described embodiment. You can get the effect of. That is, the same effects as those in the above-described embodiment can be obtained by performing parameter control by the controller 121 described above for each cycle.

<Other embodiment>

In addition, in the above embodiment, the process parameters for each batch process are determined according to the cumulative film thickness in the processing chamber, but the present disclosure is not limited thereto, and the present disclosure is used for each batch processing using conditions other than the cumulative film thickness in the processing chamber. It is also possible to apply when determining the process parameters of. Specifically, a correction table in which the number of cycles is set according to the number of wafers 200 per batch process or the surface area of the wafer 200 is stored in the storage device 121c, and process parameters for each batch process are determined using these conditions. It is possible to apply it even when making a decision.

In addition, in the above embodiment, an example in which the film thickness of the film formed on the wafer 200 increases as the cumulative film thickness in the processing chamber increases, but the present disclosure is not limited thereto. Formation of a film type such as a decrease in the film thickness of the film formed on (200), a film type such as that there is no film thickness stabilizer, or a film type such as that the film thickness changes after the film thickness stabilizer It is also possible to apply it in the case of doing so. Specifically, in the case of forming a film type such that the film thickness of the film formed on the wafer 200 decreases as the cumulative film thickness in the processing chamber increases, for example, increasing the number of cycles according to the cumulative film thickness in the processing chamber increases. Process parameters are determined using a calibration table.

In addition, in the above embodiment, a case where the number of cycles is changed as a process parameter according to the cumulative film thickness in the processing chamber is used, but the present disclosure is not limited thereto, and the present disclosure is not limited to the gas supply time, the gas supply amount, or the processing chamber It is also possible to apply when determining process parameters using correction tables such as determining pressure or step time. In addition, it is possible to apply it to the case of determining a process parameter using a correction table such as determining a cycle according to a gas supply time or the like. It is also possible to apply a plurality of correction tables to determine a plurality of process parameters for each batch process.

In addition, in the above embodiment, an example in which the number of cycles per batch processing is determined according to the accumulated film thickness in the processing chamber has been described, but the present disclosure is not limited thereto, and the present disclosure refers to the number of cycles per batch processing as a TiN film forming step or a W film forming step. It is also possible to apply it in the case of determining every predetermined cycle such as, etc., and it is also possible to apply it in the case of determining every predetermined film thickness.

In addition, in the above embodiment, a case where a TiN film is formed as a metal film has been described, but the present disclosure is not limited thereto, and the present disclosure uses metal elements such as titanium (Ti), tungsten (W), copper (Cu), and ruthenium (Ru). A metal film containing, a group 14 element-based film such as silicon (Si), germanium (Ge), and carbon (C), a combination of a metal element such as titanium silicon (TiSi), silicon germanium (SiGe) and a group 14 element, etc. It is possible to apply even when forming a film of.

As described above, various typical embodiments of the present disclosure have been described, but the present disclosure is not limited to such embodiments, and may be used in appropriate combinations.

10: substrate processing apparatus 121: controller
200: wafer (substrate) 201: processing chamber

Claims (18)

A processing chamber accommodating a substrate;
A heating unit for heating the interior of the processing chamber;
A control unit controlling to be able to form a film on the substrate based on a set process parameter;
A calculation unit that calculates a film thickness attached to the processing chamber; And
A storage unit that stores an accumulated value of the film thickness calculated by the calculation unit as an accumulated film thickness
And,
The control unit is configured to be capable of determining a set value other than the temperature of the process parameter according to the accumulated film thickness stored in the storage unit. The method of claim 1,
The control unit is configured to be capable of determining a set value other than the temperature of the process parameter according to the accumulated film thickness stored in the storage unit by using a table or calculation formula prepared in advance. The method of claim 1,
The control unit is configured to be capable of determining a set value other than the temperature of the process parameter using conditions other than the accumulated film thickness. The method of claim 2,
The control unit is configured to be capable of determining a set value other than the temperature of the process parameter using conditions other than the accumulated film thickness. The method of claim 1,
The control unit is configured to calculate data including at least one of the number of cycles, pressure, gas flow rate, and step time as the process parameter. The method of claim 1,
The control unit includes the process parameter data of the number of cycles,
A substrate processing apparatus configured to calculate the number of cycles according to a set film thickness to be deposited on the substrate. (a) accommodating the substrate in the processing chamber;
(b) heating the inside of the processing chamber;
(c) forming a film on the substrate based on set process parameters;
(d) calculating the thickness of the film deposited in the processing chamber;
(e) storing the calculated accumulated film thickness as the accumulated film thickness; And
(f) The process of determining a set value other than the temperature of the process parameter according to the stored accumulated film thickness.
A method of manufacturing a semiconductor device comprising a. The method of claim 7,
In the step (f), a set value other than the temperature of the process parameter is determined according to the accumulated film thickness stored in the storage unit using a table or calculation formula prepared in advance. The method of claim 7,
The method of manufacturing a semiconductor device, wherein in the step (f), a set value other than the temperature of the process parameter can be determined using conditions other than the accumulated film thickness. The method of claim 8,
The method of manufacturing a semiconductor device, wherein in the step (f), a set value other than the temperature of the process parameter can be determined using conditions other than the accumulated film thickness. The method of claim 7,
The process parameter includes at least one of cycle number, pressure, gas flow rate, and step time. The method of claim 7,
The process parameter contains data of the number of cycles,
In the step (f), a method of manufacturing a semiconductor device is performed to determine the number of cycles according to a set film thickness formed on the substrate. (a) accommodating a substrate in a processing chamber of a substrate processing apparatus;
(b) heating the inside of the processing chamber;
(c) forming a film on the substrate based on the set process parameters;
(d) calculating a film thickness attached to the processing chamber;
(e) storing the calculated accumulated film thickness as the accumulated film thickness; And
(f) determining a set value other than the temperature of the process parameter according to the stored accumulated film thickness.
A recording medium in which a program for causing the substrate processing apparatus to be executed by a computer is recorded. The method of claim 13,
In the step (f), a set value other than the temperature of the process parameter is determined according to the accumulated film thickness stored in the storage unit by using a table or calculation formula prepared in advance. The method of claim 13,
In the step (f), it is possible to determine a set value other than the temperature of the process parameter using conditions other than the accumulated film thickness. The method of claim 13,
In the step (f), it is possible to determine a set value other than the temperature of the process parameter by using conditions other than the accumulated film thickness. The method of claim 13,
The process parameter includes at least one of cycle number, pressure, gas flow rate, and step time. The method of claim 13,
The process parameter contains data of the number of cycles,
In the step (f), the recording medium is calculated to determine the number of cycles according to a set film thickness to be deposited on the substrate.

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