Film Formation Method and Heat Treatment Apparatus

Abstract

To improve temperature controllability.SOLUTION: A film deposition method performed in a heat treatment device including a treatment vessel, a tubular member in the treatment vessel, a heating part for heating the inside of the treatment vessel and a gas supply part comprises the steps of: preparing a substrate in the tubular member; controlling temperature in the tubular member by the heating part; and supplying gas including film deposition gas to the treatment vessel from the gas supply part to deposit a film on the substrate. The step of controlling the temperature supplies gas including heat transfer gas to the treatment vessel from the gas supply part.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a film forming method and a heat treatment apparatus.

Background Art

[0002] For example, it has been proposed to measure the temperature inside a processing container of a semiconductor manufacturing apparatus and use the measurement result for controlling the process conditions of substrate processing executed inside the processing container (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a processing container in a vacuum state, heat transfer takes time and may affect temperature control.

[0005] The present disclosure provides a technique capable of improving temperature controllability.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, there is provided a film forming method executed in a heat treatment apparatus including a processing container, a tubular member inside the processing container, a heating unit that heats the inside of the processing container, and a gas supply unit, the method including: preparing a substrate inside the tubular member; adjusting the temperature inside the tubular member by the heating unit; after adjusting the temperature, supplying a gas containing a film forming gas from the gas supply unit into the processing container to form a film on the substrate. The step of forming the film includes a plurality of steps of supplying a gas containing a film-forming gas, determines the necessity of a step of adjusting the temperature when shifting from the current step to the next step among the plurality of steps, and, when the step of adjusting the temperature is necessary, before the next step There is provided a film forming method in which, in the step of adjusting the temperature, a gas containing a heat transfer gas is supplied from the gas supply unit into the processing container.

Effects of the Invention

[0007] According to one aspect, the temperature controllability can be improved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. In each drawing, the same reference numerals are assigned to the same components, and redundant descriptions may be omitted.

[0010] [Heat Treatment Apparatus] With reference to FIG. 1, the heat treatment apparatus 1 of the embodiment will be described. FIG. 1 is a schematic diagram showing an example of the heat treatment apparatus 1 of the embodiment.

[0011] The heat treatment apparatus 1 includes a processing container 10 and a tubular member 2. The processing container 10 has a substantially cylindrical shape. The tubular member 2 is disposed inside the processing container 10 and has an inner tube 11 and an outer tube 12.The processing container 10 forms a furnace of the heating unit 40 by covering the outside of the tubular member 2. The inner tube 11 has a substantially cylindrical shape. The inner tube 11 is formed of a heat-resistant material such as quartz, for example. The inner tube 11 houses the substrate W. The inner tube 11 is also referred to as an inner tube.

[0012] The outer tube 12 has a substantially cylindrical shape with a ceiling and is provided concentrically around the inner tube 11. The outer tube 12 is formed of a heat-resistant material such as quartz, for example. The outer tube 12 is also referred to as an outer tube. The heat treatment apparatus 1 has a double structure formed by the tubular member 2 and the processing container 10.

[0013] The heat treatment apparatus 1 includes a manifold 13, gas supply pipes 21, 22, 23, a gas outlet 15, a lid 16, and the like. The manifold 13 has a substantially cylindrical shape. The manifold 13 supports the lower ends of the inner tube 11 and the outer tube 12. The manifold 13 is formed of, for example, stainless steel.

[0014] The gas supply unit 20 is provided in the manifold 13 and introduces gas into the inner tube 11. The gas supply unit 20 includes a plurality (three in the illustrated example) of quartz gas supply pipes 21, 22, 23. Each of the gas supply pipes 21, 22, 23 extends along the longitudinal direction in the inner tube 11, and its proximal end is bent in an L shape and supported so as to penetrate the manifold 13.

[0015] The gas supply pipes 21, 22, and 23 are installed in a row along the circumferential direction within the nozzle accommodating portion 27 of the inner pipe 11. A plurality of gas holes h are formed at predetermined intervals along the longitudinal direction of each of the gas supply pipes 21, 22, and 23. Each gas hole h discharges each gas in the horizontal direction. The predetermined interval is set to be the same as, for example, the interval between the substrates W supported by the wafer boat 18. Also, the position in the height direction is set so that each gas hole h is located in the middle between the vertically adjacent substrates W, enabling each gas to be efficiently supplied to the space between the substrates W. Gas supply sources 24, 25, and 26 are connected to the gas supply pipes 21, 22, and 23 via flow controllers, valves, etc., respectively. The gas supply sources 24, 25, and 26 are sources of a film-forming gas, a cleaning gas, and a heat transfer gas, respectively. Each gas from the gas supply sources 24, 25, and 26 has its flow rate controlled by a flow controller and is supplied into tubular member 2 through the respective gas supply pipes 21, 22, and 23 as needed.

[0016] In this embodiment, the film-forming gas is a gas used for forming a metal film such as a molybdenum (Mo) film. In the example of FIG. 1, a case where one gas supply pipe 21, 22, and 23 is arranged is shown, but a plurality of gas supply pipes 21, 22, and 23 may be provided.

[0017] The gas outlet 15 is formed in the manifold 13. An exhaust pipe 32 is connected to the gas outlet 15. tubular member 2 The gas supplied into is exhausted by the exhaust portion 30 via the gas outlet 15.

[0018] The lid 16 hermetically seals the opening at the lower end of the manifold 13. The lid 16 is formed of, for example, stainless steel. A wafer boat 18 is placed on the lid 16 via a heat-insulating cylinder 17. The heat-insulating cylinder 17 and the wafer boat 18 are formed of a heat-resistant material such as quartz, for example. The wafer boat 18 holds a plurality of substrates W substantially horizontally with a predetermined interval in the vertical direction. The wafer boat 18 is lifted by the lifting portion 19 raising the lid 16 tubular member 2is loaded into, tubular member 2 and is accommodated therein. The wafer boat 18 is unloaded from the inside when the lifting part 19 lowers the lid body 16. tubular member 2 An example of the substrate W is a wafer.

[0019] The heat treatment apparatus 1 includes an exhaust part 30, a heating part 40, a cooling part 50, a control device 90, etc. The exhaust part 30 includes an exhaust device 31, an exhaust pipe 32, and a pressure controller 33. The exhaust device 31 is a vacuum pump such as a dry pump or a turbo molecular pump, for example. The exhaust pipe 32 connects the gas outlet 15 and the exhaust device 31. The pressure controller 33 is provided in the exhaust pipe 32 and controls the pressure inside by adjusting the conductance of the exhaust pipe 32. The pressure controller 33 is an automatic pressure control valve, for example. tubular member 2 The pressure inside is controlled. The pressure controller 33 is an automatic pressure control valve, for example.

[0020] The heating part 40 includes a heat insulating material 41, a heater 42, and an outer skin 43. The heat insulating material 41 and the outer skin 43 form the processing container 10 according to the embodiment. The heat insulating material 41 has a substantially cylindrical shape and is provided around the outer tube 12. The heat insulating material 41 is formed mainly of silica and alumina. The heater 42 is an example of a heating element and is provided on the inner circumference of the heat insulating material 41. The heater 42 is provided linearly or in a planar shape on the side wall of the processing container 10 so that temperature control can be performed by dividing it into a plurality of zones in the height direction of the processing container 10. The outer skin 43 is provided so as to cover the outer circumference of the heat insulating material 41. The outer skin 43 holds the shape of the heat insulating material 41 and reinforces the heat insulating material 41. The outer skin 43 is formed of a metal such as stainless steel. Further, in order to suppress the heat influence to the outside of the heating part 40, a water cooling jacket (not shown) may be provided on the outer circumference of the outer skin 43. Such a heating part 40 determines the heat generation amount of the heater 42 by the power supplied to the heater 42, and thereby heats the inside of the processing container 10 until it reaches a desired temperature.

[0021] The cooling unit 50 supplies air (air) toward the processing container 10 to cool the substrate W in the processing container 10. The air is an example of a cooling fluid. The cooling unit 50 supplies air toward the processing container 10, for example, when rapidly cooling the substrate W after heat treatment. The cooling unit 50 includes a fluid flow path 51, a blowout hole 52, a distribution flow path 53, a flow rate adjustment unit 54, and a waste heat outlet 55.

[0022] A plurality of fluid flow paths 51 are formed in the height direction between the heat insulating material 41 and the outer skin 43. The fluid flow path 51 is, for example, a flow path formed along the circumferential direction outside the heat insulating material 41.

[0023] The blowout holes 52 are formed to penetrate the heat insulating material 41 from each fluid flow path 51, and blow out air into the space between the outer pipe 12 and the heat insulating material 41.

[0024] The distribution flow path 53 is provided outside the outer skin 43 and distributes and supplies air to each fluid flow path 51. The flow rate adjustment unit 54 is interposed in the distribution flow path 53 and adjusts the flow rate of the air supplied to the fluid flow path 51.

[0025] The waste heat outlet 55 is provided above the plurality of blowout holes 52 and discharges the air supplied to the space between the outer pipe 12 and the heat insulating material 41 to the outside of the heat treatment apparatus 1. The air discharged to the outside of the heat treatment apparatus 1 is cooled by, for example, a heat exchanger and supplied again to the distribution flow path 53. However, the air discharged to the outside of the heat treatment apparatus 1 may be discharged without being reused.

[0026] The temperature sensor 60 detects the temperature inside the tubular member 2. The temperature sensor 60 is provided, for example, inside the inner tube 11. However, the temperature sensor 60 may be provided at a position where it can detect the temperature inside the tubular member 2, for example, in the space between the inner tube 11 and the outer tube 12. The temperature sensor 60 has a plurality of temperature measurement parts 61 to 65 provided at different positions in the height direction corresponding to a plurality of zones. The temperature measurement parts 61 to 65 are provided corresponding to the zones "TOP", "C-T", "CTR", "C-B", and "BTM", respectively. The plurality of temperature measurement parts 61 to 65 may be, for example, thermocouples or resistance temperature detectors. The temperature sensor 60 transmits the temperatures detected by the plurality of temperature measurement parts 61 to 65 to the control device 90.

[0027] The temperature sensors 71 to 75 (hereinafter also collectively referred to as "temperature sensor 70") are inserted from the outside of the processing container 10 into the space between the processing container 10 and the tubular member 2. As a result, the temperature measurement parts of the temperature sensor 70 are arranged at substantially the same height as the temperature measurement parts 61 to 65 corresponding to the zones "TOP", "C-T", "CTR", "C-B", and "BTM". Each of the temperature measurement parts of the temperature sensor 70 may be, for example, a thermocouple or a resistance temperature detector. The temperature sensor 70 transmits the temperatures detected by the plurality of temperature measurement parts to the control device 90.

[0028] The number of temperature measurement parts of the temperature sensors 60 and 70 is not limited to five, and may be seven or any other number of one or more. There is a temperature sensor 70 near the heater 42, and the heater 42, the temperature measurement parts of the temperature sensor 70, and the temperature sensor 60 are paired. The temperature inside the tubular member 2 measured by the temperature sensor 60 is also denoted as "Inner temperature". The temperature outside the tubular member 2 and inside the processing container 10 measured by the temperature sensor 70 is also denoted as "Outer temperature".

[0029] The control device 90 controls the operation of the heat treatment device 1. The control device 90 may be, for example, a computer. The program of the computer that performs the overall operation of the heat treatment device 1 is stored in a storage medium. The storage medium may be, for example, a flexible disk, a compact disk, a hard disk, a flash memory, a DVD, etc.

[0030] [Overheating of the Outer Temperature] Normally, in the heat treatment apparatus 1, the temperature (Inner temperature) in the region inside the tubular member 2 (hereinafter also referred to as the "Inner region") is raised to the target temperature set in the recipe to perform a desired film formation process on the substrate W. At this time, by controlling the power of the heater 42 provided in the region outside the tubular member 2 and inside the processing vessel 10 (hereinafter also referred to as the "Outer region"), heat is transferred from the Outer region to the Inner region, and the Inner temperature is raised to the target temperature. In this specification, the target temperature is the target temperature of the Inner region to be temperature-controlled.

[0031] However, when forming a metal film with a high reflectance such as a molybdenum film on the substrate W in the heat treatment apparatus 1, a molybdenum film adheres to the tubular member 2 (the surface of the inner tube 11 and the inner surface of the outer tube 12) during the formation of the molybdenum film. Since the reflectance of the molybdenum film is as high as about 0.97, the molybdenum film adhering to the inside of the tubular member 2 functions as a reflective film. When the surface of the inner tube 11 and the inner surface of the outer tube 12 are covered with a film having a high reflectance, the heat insulation effect due to the double structure of the tubular member 2 is enhanced, and it takes time for heat to be transferred from the Outer region to the Inner region.

[0032] FIG. 2 is a graph for explaining the problem of overheating in the processing vessel 10. FIG. 2(a) is a graph showing an example of the Inner temperature, where the horizontal axis of the graph is time and the vertical axis is temperature. The Inner temperature is gradually rising due to the control of the power of the heater 42 shown in FIG. 2(b).

[0033] However, the molybdenum film adhering to the inside of the tubular member 2 functions as a reflective film, and it takes time for heat to be transferred from the Outer region to the Inner region due to the double structure of the tubular member 2. Even if the power of the heater 42 is increased, the Inner temperature does not immediately rise. For this reason, the power of the heater 42 is further increased. In the example of FIG. 2(b), the power of the heater 42 is further increased when the time is less than 30 minutes.

[0034] This shows the state where the Outer temperature has risen excessively beyond the preset over-temperature at point P in Fig. 2(c). Fig. 2(c) is a graph showing an example of the Outer temperature, where the horizontal axis of the graph is time and the vertical axis is temperature. Due to the increase in the power of the heater 42, the Outer temperature exceeded the over-temperature (1050 °C) slightly before 30 minutes. When the over-temperature is exceeded, the heater 42 is shut down for safety reasons, and the heating by the heater 42 is stopped.

[0035] In order to avoid the excessive temperature rise of the Outer temperature described above, it is also conceivable to control the power of the heater 42 so that the Inner temperature rises slowly. Then, although the Outer temperature does not exceed the over-temperature, it takes time for the Inner temperature to rise to the target temperature, resulting in a decrease in productivity. Considering productivity, it is important to control the Inner temperature to the target temperature as quickly as possible while avoiding excessive temperature rise.

[0036] Therefore, in the present disclosure, a film forming method capable of shortening the time for controlling the Inner temperature to the target temperature is proposed. The film forming method according to the embodiment is controlled by the control device 90 and executed by the heat treatment device 1. Hereinafter, the functional configuration and hardware configuration of the control device 90 will be described with reference to Figs. 3 and 4, and then the film forming method according to the embodiment will be described. Fig. 3 is a diagram showing an example of the functional configuration of the control device 90 according to the embodiment. Fig. 4 is a diagram showing an example of the hardware configuration of the control device 90 according to the embodiment. In the following description, an example of forming a molybdenum film in the film forming method according to the embodiment will be described.

[0037] Referring to Fig. 3, the control device 90 includes a control unit 150 and a storage unit 160. The storage unit 160 stores a recipe in which the procedure for forming a molybdenum film on the substrate W is set. In the recipe, process conditions such as gas type, gas flow rate, pressure, temperature, and processing time are set for each of one or more steps.

[0038] The control unit 150 includes an acquisition unit 151, a temperature control unit 152, a film formation control unit 153, a heater control unit 154, and a gas control unit 155. The acquisition unit 151 acquires the Inner temperature from the temperature sensor 60 (Inner TC).

[0039] The temperature control unit 152 controls the Inner region to reach the target temperature based on the acquired Inner temperature. The heater control unit 154 controls the power of the heater 42. Thereby, the temperature control unit 152 adjusts the Inner temperature. The film formation control unit 153 forms a molybdenum film on the substrate W according to the process conditions set in the recipe. The gas control unit 155 supplies film formation gas, cleaning gas, etc. Also, the gas control unit 155 supplies heat transfer gas during temperature control for temperature stabilization, heating, and cooling in the Inner region.

[0040] An example of the hardware configuration of the control device 90 will be described with reference to FIG. 4. The control device 90 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an I / O port 104, an operation panel 105, and an HDD 106 (Hard Disk Drive). Each unit is connected by a bus B.

[0041] The CPU 101 controls various operations of the heat treatment apparatus 1, film formation processes, cleaning processes, etc. based on various programs read into the RAM 103 and a recipe that defines the processing procedures for film formation processes, cleaning processes, etc. The programs include a program for executing the film formation method according to the embodiment. The CPU 101 executes the film formation method according to the embodiment based on these programs read into the RAM 103.

[0042] The ROM 102 is composed of an EEPROM (Electrically Erasable Programmable ROM), a flash memory, a hard disk, etc., and is a storage medium for storing programs, recipes, etc. of the CPU 101. The RAM 103 functions as a work area, etc. of the CPU 101.

[0043] The I / O port 104 acquires values of various sensors that detect temperature, pressure, gas flow rate, etc. from various sensors attached to the heat treatment apparatus 1 and transmits them to the CPU 101. Also, the I / O port 104 outputs a control signal output by the CPU 101 to each part of the heat treatment apparatus 1. An operation panel 105 for an operator (user) to operate the heat treatment apparatus 1 is connected to the I / O port 104.

[0044] The HDD 106 is an auxiliary storage device and may store process recipes, programs, etc. Also, the HDD 106 may store log information of measurement values measured by various sensors.

[0045] The storage unit 160 can be realized by any one of the ROM 102, the RAM 103, the EEPROM, the flash memory, and the HDD 106. The acquisition unit 151 can be realized by the I / O port 104. The temperature control unit 152, the film formation control unit 153, the heater control unit 154, and the gas control unit 155 can be executed by the CPU 101.

[0046] [Improvement of temperature controllability] Next, with reference to FIG. 5, a method for improving the temperature controllability by H gas according to the embodiment will be described in comparison with a reference example. FIGS. 5(a) and (c) show the temperature control by N gas in the reference example. 2 A method for improving the temperature controllability by H gas will be described in comparison with a reference example. FIGS. 5(a) and (c) show the temperature control by N gas in the reference example. 2 FIGS. 5(b) and (d) show the temperature control by H gas in the embodiment. 2 FIGS. 5(a) to (d) show the time until the temperature in the Inner region reaches the target temperature. FIG. 5(a) shows from the gas supply unit 20 tubular member 2 into N 2This is the case where, while supplying gas, the Inner region is controlled based on the Inner temperature acquired from the temperature sensor 60 so as to reach the target temperature. In this case, undershoot and overshoot occur until the temperature stabilizes at the target temperature.

[0047] On the other hand, Fig. 5(b) shows from the gas supply unit 20 tubular member 2 inside H 2 This is the case where, while supplying gas, the Inner region is controlled based on the Inner temperature acquired from the temperature sensor 60 so as to reach the target temperature. In this case, after undershoot occurred, it was controlled to the target temperature. As a result, overshoot was suppressed and the time until reaching the target temperature could be shortened.

[0048] Fig. 5(c) shows from the gas supply unit 20 tubular member 2 inside N 2 This is the case where the Inner region is cooled down to the target temperature while supplying gas. On the other hand, Fig. 5(d) shows from the gas supply unit 20 tubular member 2 inside H 2 This is the case where the Inner region is cooled down to the target temperature while supplying gas. As a result, when supplying the H 2 gas shown in Fig. 5(d), the cooling time could be shortened to about 1 / 4 compared to the case of supplying the N 2 gas shown in Fig. 5(c).

[0049] H 2 The thermal conductivity of the H gas at 500 °C is 267 mW / (m·K). The thermal conductivity of the N 2 gas at 500 °C is 38.64 mW / (m·K). The H 2 gas has a thermal conductivity about 7 times that of the N 2 gas. Thus, by supplying a gas with a high thermal conductivity such as the H 2 gas into the [inner part], heat conduction can be significantly improved and the temperature adjustment (temperature stabilization) time of the Inner region can be significantly shortened. tubular member 2 inside

[0050] [Film Formation Method] Next, taking the case of forming a film on a substrate using the heat treatment apparatus 1 as an example, a film formation method including temperature adjustment according to an embodiment will be described. FIG. 6 is a flowchart showing an example of the film formation method according to the embodiment.

[0051] First, the wafer boat 18 holding a plurality of substrates W is raised by the elevating unit 19 and carried into (loaded into) the loading area, and the opening at the lower end of the lid 16 is tubular member 2 airtightly sealed to prepare the substrate W (step S1). Next, tubular member 2 is evacuated (step S3).

[0052] In step S1, tubular member 2 the opening at the lower end is opened, and the relatively low-temperature substrate W is carried into the loading area, causing the temperature in the Inner region to drop. The heater control unit 154 controls the power of the heater 42 based on the detected temperatures of the temperature measuring units 61 to 65 of the temperature sensor 60 so that the temperature in the lowered tubular member 2 is maintained at a set temperature (for example, 300 to 700°C) determined in advance by a recipe or the like. Thereby, the temperature control unit 152 adjusts the temperature in the Inner region to the target temperature (step S5). Also, the gas control unit 155 tubular member 2 supplies H 2 gas into (step S7). Note that step S5 and step S7 may be simultaneous, or step S5 may be started after step S7 is started.

[0053] Next, the temperature control unit 152 determines whether the temperature in the Inner region has reached the target temperature (step S9). If the temperature control unit 152 determines that the temperature has not reached the target temperature, it returns to step S5 and repeats steps S5 to S9 until the target temperature is reached. When it is determined in step S9 that the target temperature has been reached, the temperature control unit 152 determines that the temperature in the Inner region has stabilized and completes the temperature adjustment, and the film formation control unit 153 executes the molybdenum film formation process (step S11).

[0054] An example of the film formation process in step S11 will be described later with reference to the flowchart of FIG. 8. After the film formation process in step S11, the wafer boat 18 holding a plurality of substrates W is carried out (unloaded) outside by the elevating unit 19, and this process is terminated (step S13). tubular member 2 and this process is terminated (step S13).

[0055] As described above, the film formation method according to the present embodiment has been described. In the film formation method according to the present embodiment, a step of preparing a substrate in a processing container, a step of adjusting the temperature in the processing container by a heating unit, and after adjusting the temperature, a step of supplying a gas from a gas supply unit into the processing container to form a film on the substrate, and in the step of adjusting the temperature, a gas containing a heat transfer gas is supplied from the gas supply unit into the processing container. Thereby, by supplying the heat transfer gas during temperature adjustment, the heat transfer effect can be enhanced and the temperature controllability can be improved.

[0056] [An example of the effect] An example of the effect of the film formation method according to the embodiment described above will be described with reference to FIG. 7. FIG. 7 is a diagram showing an example of the effect of supplying a heat transfer gas by the film formation method according to the embodiment.

[0057] FIGS. 7(a) to 7(c) are reference examples. FIGS. 7(a) to 7(c) show the detected temperatures (vertical axis) by the temperature measuring units 61, 63, and 65 of the temperature sensor 60 with respect to the time (horizontal axis) when Ar gas is supplied into the processing container during the temperature adjustment step in the sequence of load → evacuation → temperature adjustment (temperature stabilization) → film formation. FIGS. 7(d) to 7(f) are the present embodiment. FIGS. 7(d) to 7(f) show the detected temperatures (vertical axis) by the temperature measuring units 61, 63, and 65 of the temperature sensor 60 with respect to the time (horizontal axis) when H 2 gas is supplied into the processing container during the temperature adjustment step in the sequence of load → evacuation → temperature adjustment (temperature stabilization) → film formation.

[0058] In FIG. 7, the target temperatures of zones “TOP”, “CTR” and “BTM” are indicated by “Target TOP”, “Target CTR” and “Target BTM”. These target temperatures may be set to the same temperature or different temperatures. In the example of FIG. 7, “Target TOP”, “Target CTR” and “Target BTM” are 370°C.

[0059] The temperatures of the Inner regions of the respective zones are indicated by “Inner TOP”, “Inner CTR” and “Inner BTM”. Also, the powers of the heaters 42 in the respective zones are indicated by “Power TOP”, “Power CTR” and “Power BTM”. The air output is indicated by “Power Air”.

[0060] Referring to FIGS. 7(a) and 7(d), from the start of loading (0 minutes) to about 6 minutes, since the wafer boat 18 was carried into the loading area, the temperature of the Inner region decreased due to the temperature of, for example, 100 substrates W that were carried in. For this reason, the detected temperatures measured by the temperature sensors 60 (temperature measuring parts 61, 63, 65) decreased.

[0061] Therefore, as shown in FIGS. 7(c) and 7(f), the outputs of the heaters in the respective zones indicated by “Power CTR” and “Power BTM” increased from about 6 minutes, and the heater of “Power TOP” was outputted with a delay, and the Inner region was controlled to be heated up. However, from about 6 minutes, evacuation (vacuum pumping) by the evacuation part 30 was started, tubular member 2 and since the inside became a reduced-pressure atmosphere, heat conduction deteriorated. Note that the air was outputted from the start of the process as indicated by “Power Air”. The air has the effect of promoting temperature adjustment and the evacuation of Ar gas or H 2 gas. However, the air may or may not be supplied.

[0062] At around 26 minutes, the output of the heaters in each zone increased sharply and the temperature stopped decreasing. Then, as the temperature of each zone was adjusted to the target temperature, the temperature of each zone began to rise. In FIG. 7, the supply of Ar gas or H 2 gas started at around 30 minutes.

[0063] In the temperature control of the reference example, as shown in FIG. 7(c), during the temperature adjustment (temperature stabilization), the output of the heater of "Power BTM" was large, and the power of the heaters 42 of "Power TOP" and "Power CTR" was hardly output. This is due to the fact that heat is difficult to transfer from the Outer region to the Inner region, resulting in an excessive increase in the output of the heater of "Power BTM". As a result, as shown in the enlarged view of FIG. 7(b), overshoot occurred, and the temperatures of the Inner regions of the center and the top exceeded the target temperature.

[0064] In the temperature control of the embodiment, as shown in FIG. 7(f), during the temperature adjustment (temperature stabilization), the powers of the heaters 42 of "Power TOP", "Power CTR", and "Power BTM" are all output. This is considered to be because the heat transfer effect from the Outer region to the Inner region is enhanced by H 2 gas, and the powers of the heaters 42 in each zone are output normally. As a result, as shown in the enlarged view of FIG. 7(e), overshoot did not occur, and the temperatures of the Inner regions of each zone did not exceed the target temperatures of each zone. From the above results, in the film forming method according to the embodiment, the temperature controllability can be improved and the time for temperature stabilization can be shortened.

[0065] [Film Forming Process] Next, the details of the film forming process executed in step S11 of FIG. 6 will be described with reference to FIG. 8. FIG. 8 is a flowchart showing an example of the details of the film forming process of step S11 of FIG. 6. In the film forming process, the gas supply unit 20 stops the supply of H 2 gas and supplies the film forming gas (step S21).

[0066] Next, the film formation control unit 153 forms a molybdenum film on the substrate W based on the recipe (step S23). Next, the film formation control unit 153 determines whether there is a next step (step S25). If it is determined that there is a next step, the temperature control unit 152 determines whether to control the temperature increase or decrease of the Inner region before performing the film formation of the next step (step S27). In step S27, when the temperature control unit 152 determines to control the temperature increase or decrease of the Inner region, it controls the power of the heater 42 based on the detected temperatures of the temperature measuring units 61 to 65 of the temperature sensor 60, and supplies H 2 gas (step S29).

[0067] Next, the temperature control unit 152 determines whether the target temperature has been reached (step S31). If it is determined that the target temperature has not been reached, it returns to step S29 and repeats steps S29 to S31 until the target temperature is reached. When the temperature control unit 152 reaches the target temperature, it returns to step S21 and forms a film on the substrate W in steps S21 to S23.

[0068] In step S27, when the temperature control unit 152 determines not to control the temperature increase or decrease of the Inner region, it determines whether to control the temperature stabilization of the Inner region (step S33). In step S33, when the temperature control unit 152 determines to control the temperature stabilization of the Inner region, it controls the power of the heater 42 based on the detected temperatures of the temperature measuring units 61 to 65 of the temperature sensor 60, and supplies H 2 gas (step S29). Next, the temperature control unit 152 determines whether the target temperature has been reached (step S31). If it is determined that the target temperature has not been reached, it returns to step S29 and repeats steps S29 to S31 until the target temperature is reached. When the temperature control unit 152 reaches the target temperature, it returns to step S21 and forms a film on the substrate W in steps S21 to S23.

[0069] In step S31, when the temperature control unit 152 determines not to control the temperature stabilization of the Inner region, it returns to step S21 and forms a film on the substrate W in steps S21 to S23. When it is determined in step S25 that there is no next step, this process ends.

[0070] The film formation method according to the present embodiment has been described above. In the film formation method according to the present embodiment, when the step of forming a film on the substrate W has a plurality of steps, a step of determining whether to have a step of adjusting the temperature before executing each step, and when it is determined in this determination step that there is a step of adjusting the temperature, a gas containing a heat transfer gas is supplied for a predetermined time in the step of adjusting the temperature. By supplying a gas containing a heat transfer gas not only during the stabilization of the temperature in the Inner region but also during the temperature increase or decrease in the Inner region in the step of adjusting the temperature, the temperature controllability can be improved.

[0071] [An example of the effect] An example of the effect of the film formation method according to the embodiment described above will be described with reference to FIG. 9. FIG. 9 is a diagram showing an example of the effect of the supply of the heat transfer gas by the film formation method according to the embodiment.

[0072] FIG. 9(a) is a reference example, and FIG. 9(b) is the present embodiment. FIG. 9(a) shows the detected temperatures (vertical axis) by the temperature measuring parts 61, 63, and 65 of the temperature sensor 60 with respect to the time (horizontal axis) when Ar gas is supplied into the processing chamber during the step of controlling the temperature decrease of the Inner region to the target temperature. FIG. 9(b) shows the detected temperatures (vertical axis) by the temperature measuring parts 61, 63, and 65 of the temperature sensor 60 with respect to the time (horizontal axis) when H 2 gas is supplied into the processing chamber during the step of controlling the temperature decrease of the Inner region to the target temperature.

[0073] According to this, when H 2 gas is supplied during the temperature decrease in each zone of "Inner TOP", "Inner CTR", and "Inner BTM", it is possible to shorten the time to reach the target temperature by about 150 minutes compared to when Ar gas is supplied during the temperature decrease. That is, since the heat transfer effect by H 2 gas is enhanced, in this example, the temperature adjustment time can be shortened to about 1 / 4.

[0074] The same effect can be obtained for temperature increase. Thus, the temperature of the Inner region can be increased or decreased to the target temperature in a short time. For example, at the timing when temperature stabilization, increase, and decrease of the Inner region are required before film formation or between steps during film formation, H 2 By supplying a heat transfer gas such as H gas, the efficiency of the heat transfer gas transferring the heat of the heater 42 from the Outer region to the Inner region can be enhanced. Thereby, improvement in temperature controllability such as shortening of the temperature adjustment time due to the improved heat transfer effect becomes possible.

[0075] The heat transfer gas is not limited to H 2 gas, and for example, a gas with high thermal conductivity such as He can be used. The heat transfer gas is H 2 gas, only a gas with high thermal conductivity such as He, or a mixed gas containing other gases may also be used.

[0076] In the following embodiments, as an example of the film formation method, a film formation method by chemical vapor deposition (CVD) was described, but it is not limited thereto, and it can be similarly applied in, for example, atomic layer deposition (ALD).

[0077] For example, in the film formation method by ALD, during film formation, H 2 gas, film formation gas (for example, reaction gas), H 2 gas, film formation gas (for example, reducing gas) ··· may be alternately supplied repeatedly. Thereby, the temperature adjustment time before film formation by the film formation gas can be shortened.

[0078] Note that the film formation method according to the embodiment is not limited to a molybdenum film, and a metal film such as a tungsten film or a niobium film may be formed. Alternatively, a film other than a metal film may be formed.

[0079] The film formation method and the heat treatment apparatus according to the embodiments disclosed this time should be considered illustrative and not restrictive in all respects. The embodiments can be modified and improved in various forms without departing from the scope and gist of the appended claims. The matters described in the above-described plurality of embodiments can also adopt other configurations and can be combined within a non-contradictory range.

Explanation of Signs

[0080] 1 Heat treatment apparatus 2 Tubular member 10 Processing container 20 Gas supply unit 21, 22, 23 Gas supply pipes 42 Heater 90 Control device 150 Control unit

Claims

1. A film forming method executed in a heat treatment apparatus having a processing container, a tubular member in the processing container, a heating unit for heating the inside of the processing container, and a gas supply unit, comprising: a step of preparing a substrate in the tubular member; a step of adjusting the temperature inside the tubular member by the heating unit; after adjusting the temperature, a step of supplying a gas containing a film forming gas from the gas supply unit into the processing container to form a film on the substrate, and having: the step of forming the film includes a plurality of steps of supplying a gas containing a film forming gas, determining the necessity of the step of adjusting the temperature when shifting from the current step to the next step among the plurality of steps, and when the step of adjusting the temperature is necessary, supplying a gas containing a heat transfer gas from the gas supply unit into the processing container in the step of adjusting the temperature before the next step. A film forming method.

2. In the step of adjusting the temperature, a gas containing the heat transfer gas is supplied in at least any one of temperature controls for temperature stabilization, temperature increase, and temperature decrease inside the tubular member. The film forming method according to claim 1.

3. A gas containing the heat transfer gas is supplied at a predetermined time before the step of forming the film. The film forming method according to claim 1 or 2.

4. The heat transfer gas is H ２ gas and / or at least one of He gas. The film forming method according to any one of claims 1 to 3.

5. In the step of forming the film, a metal film is formed on the substrate. The film forming method according to any one of claims 1 to 4.

6. After making the inside of the processing container in a vacuum state, a gas containing the heat transfer gas is supplied in the step of adjusting the temperature. The film forming method according to any one of claims 1 to 5.

7. In the step of adjusting the temperature, a gas containing the heat transfer gas and air is supplied into the processing container. The film forming method according to any one of claims 1 to 6.

8. A heat treatment apparatus having a processing container, a tubular member in the processing container, a heating unit for heating the inside of the processing container, a gas supply unit, and a control unit, wherein: the control unit: controls a step of preparing a substrate in the tubular member; controls a step of adjusting the temperature inside the tubular member by the heating unit; after adjusting the temperature, controls a step of supplying a gas containing a film forming gas from the gas supply unit into the processing container to form a film on the substrate, and the step of forming the film includes a plurality of steps of supplying a gas containing a film forming gas. Determine the necessity of the step of adjusting the temperature when shifting from the current step to the next step among the plurality of steps, and when the step of adjusting the temperature is necessary, control to supply a gas containing a heat transfer gas from the gas supply unit into the processing container in the step of adjusting the temperature before the next step. A heat treatment apparatus.

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