Substrate processing apparatus and substrate processing method

Abstract

The present invention provides a substrate processing apparatus and a substrate processing method for controlling the state of the processing gas in the processing area. [Solution] A substrate processing apparatus comprising: a processing chamber; a mounting table disposed within the processing chamber on which a substrate is placed; a gas supply mechanism disposed opposite to the mounting table and supplying processing gas to the substrate; a processing area formed between the mounting table and the gas supply mechanism; an exhaust area from which the gas is exhausted by an exhaust unit; a first exhaust passage formed in the gap between the mounting table and the gas supply mechanism, through which the processing gas flows from the processing area to the exhaust area; a second exhaust passage provided in the gas supply mechanism and connected to allow the processing gas to flow from the processing area to the exhaust area; a third exhaust passage from which the processing gas is exhausted from the exhaust area; and a control unit, wherein the control unit adjusts the processing conditions of the substrate based on the gap between the mounting table and the gas supply mechanism, the supply conditions of the processing gas supplied from the gas supply mechanism, and the pressure inside the processing chamber.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] Patent Document 1 discloses a semiconductor manufacturing apparatus that forms a film on a substrate by an ALD process by forming a diffusion space between a mounting table that is lifted and lowered and a concave portion of a top plate member and supplying a processing gas to this diffusion space.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On one aspect, the present disclosure provides a substrate processing apparatus and a substrate processing method for controlling the state of a processing gas in a processing region.

Means for Solving the Problems

[0005] To solve the above problems, according to one embodiment, a substrate processing apparatus is provided, comprising: a processing chamber; a mounting table disposed in the processing chamber on which a substrate is placed; a gas supply mechanism disposed opposite to the mounting table and supplying processing gas to the substrate; a processing area formed between the mounting table and the gas supply mechanism; an exhaust area exhausted by an exhaust unit; a first exhaust passage formed in the gap between the mounting table and the gas supply mechanism, through which the processing gas flows from the processing area to the exhaust area; a second exhaust passage provided in the gas supply mechanism and connected to allow the processing gas to flow from the processing area to the exhaust area; a third exhaust passage through which the processing gas is exhausted from the exhaust area; and a control unit, wherein the control unit adjusts the processing conditions of the substrate based on the gap between the mounting table and the gas supply mechanism, the supply conditions of the processing gas supplied from the gas supply mechanism, and the pressure inside the processing chamber. [Effects of the Invention]

[0006] In one aspect, this disclosure can provide a substrate processing apparatus and a substrate processing method for controlling the state of the processing gas in the processing area. [Brief explanation of the drawing]

[0007] [Figure 1] An example of a schematic diagram showing an example of the configuration of a substrate processing device. [Figure 2] An example of a view of a showerhead from below. [Figure 3] An example of a diagram illustrating gas flow. [Figure 4] An example flowchart illustrating a substrate processing method. [Figure 5] An example of a diagram showing a recipe for a substrate processing method. [Figure 6] A graph showing an example of pressure change. [Modes for carrying out the invention]

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] [Substrate Processing Equipment] The substrate processing apparatus 100 according to this embodiment will be described with reference to Figure 1. Figure 1 is an example of a schematic diagram showing an example of the configuration of the substrate processing apparatus 100. The substrate processing apparatus 100 is a device that deposits a desired film on a substrate W such as a wafer by an ALD (Atomic Layer Deposition) process in a processing container 1 under reduced pressure. In the following description, the case in which a TiN film is deposited on the substrate W by the ALD process will be used as an example.

[0010] As shown in Figure 1, the substrate processing apparatus 100 includes a processing container (processing chamber) 1, a mounting table 2, a shower head (gas supply mechanism) 3, an exhaust unit 4, a gas supply unit 5, an RF power supply unit 8, and a control unit 9.

[0011] The processing container 1 is made of a metal such as aluminum and has a substantially cylindrical shape. The processing container 1 houses the substrate W. An inlet / outlet 11 for loading or unloading the substrate W is formed in the side wall of the processing container 1, and the inlet / outlet 11 is opened and closed by a gate valve 12. An annular exhaust duct 13 with a rectangular cross-section is provided on top of the main body of the processing container 1. A substantially annular exhaust space (exhaust area) 13a is formed in the exhaust duct 13. An exhaust port 13b is formed in the outer wall of the exhaust duct 13. A top wall 14 is provided on the upper surface of the exhaust duct 13 so as to close the upper opening of the processing container 1 via an insulating member 16. The space between the exhaust duct 13 and the insulating member 16 is airtightly sealed with a seal ring 15. The partition member 17 divides the inside of the processing container 1 vertically when the mounting base 2 (and cover member 22) rises to the processing position described later, forming an upper space and a lower space. Of the upper space of this processing container 1, the space radially outward from the processing space 38 and the annular gap 39, which will be described later, becomes the exhaust space 13a. Also, of the upper space of this processing container 1, the space radially inward from the annular gap 39, which will be described later, becomes the processing space 38.

[0012] The mounting table 2 horizontally supports the substrate W within the processing container 1. The mounting table 2 is formed in the shape of a disc corresponding to the size of the substrate W and is supported by a support member 23. The mounting table 2 is made of a ceramic material such as AlN or a metallic material such as aluminum or nickel alloy, and a heater 21 for heating the substrate W is embedded inside. The heater 21 is powered by a heater power supply (not shown) and generates heat. The output of the heater 21 is controlled by the temperature signal of a thermocouple (not shown) provided near the upper surface of the mounting table 2, thereby controlling the substrate W to a predetermined temperature. The mounting table 2 is provided with a cover member 22 made of ceramic material such as alumina so as to cover the outer peripheral region of the upper surface and the sides.

[0013] A support member 23 is provided on the bottom surface of the mounting platform 2 to support the mounting platform 2. The support member 23 extends from the center of the bottom surface of the mounting platform 2 through a hole formed in the bottom wall of the processing container 1 and downwards to the processing container 1, and its lower end is connected to a lifting mechanism 24. The lifting mechanism 24 causes the mounting platform 2 to move up and down via the support member 23 between the processing position shown by the solid line in Figure 1 and the transport position shown by the dashed line below it, where the substrate W can be transported. A flange portion 25 is attached to the lower part of the support member 23 to the processing container 1, and a bellows 26 is provided between the bottom surface of the processing container 1 and the flange portion 25, which partitions the atmosphere inside the processing container 1 from the outside air and expands and contracts in accordance with the lifting operation of the mounting platform 2.

[0014] Near the bottom of the processing container 1, three substrate support pins (only two are shown) are provided, protruding upward from the lifting plate 27a. The substrate support pins 27 are raised and lowered via the lifting plate 27a by a lifting mechanism 28 located below the processing container 1. The substrate support pins 27 are inserted through holes 2a provided in the mounting table 2 at the transport position, and are able to protrude and retract relative to the upper surface of the mounting table 2. By raising and lowering the substrate support pins 27, the substrate W is transferred between the transport mechanism (not shown) and the mounting table 2.

[0015] The shower head 3 supplies processing gas into the processing container 1 in a shower-like manner. The shower head 3 is made of metal, is positioned opposite the mounting base 2, and has approximately the same diameter as the mounting base 2. The shower head 3 has a main body 31 fixed to the top wall 14 of the processing container 1, and a shower plate 32 connected below the main body 31. A gas diffusion space 33 is formed between the main body 31 and the shower plate 32, and a gas introduction hole 36 is provided in the gas diffusion space 33 so as to penetrate the top wall 14 of the processing container 1 and the center of the main body 31. An annular projection 34 protruding downward is formed on the periphery of the shower plate 32. A gas discharge hole 35 is formed on the flat surface inside the annular projection 34. When the mounting base 2 is in the processing position, a processing space (processing area) 38 is formed between the mounting base 2 and the shower plate 32, and an annular gap (first exhaust passage) 39 is formed when the upper surface of the cover member 22 and the annular projection 34 are close together.

[0016] The exhaust unit 4 exhausts the inside of the processing container 1. The exhaust unit 4 includes an exhaust pipe (third exhaust passage) 41 connected to the exhaust port 13b, an APC (Auto Pressure Controller) valve 42, an on / off valve 43, and a vacuum pump (exhaust pump) 44. One end of the exhaust pipe 41 is connected to the exhaust port 13b of the exhaust duct 13, and the other end is connected to the suction port of the vacuum pump 44. Between the exhaust duct 13 and the vacuum pump 44, the APC valve 42 and the on / off valve 43 are provided in order from the upstream side. The APC valve 42 adjusts the pressure in the exhaust space 13a by adjusting the conductance of the exhaust path, and adjusts the pressure in the processing space 38. The on / off valve 43 switches the opening and closing of the exhaust pipe 41.

[0017] The gas supply unit 5 supplies the processing gas into the processing container 1. The gas supply unit 5 has a raw material gas supply source 51a, a reaction gas supply source 52a, and purge gas supply sources 53a and 54a.

[0018] The raw material gas supply source 51a supplies the raw material gas (first processing gas) into the processing container 1 via the gas supply line 51b. In the following description, for example, TiCl4 is used as the raw material gas.

[0019] In the gas supply line 51b, a mass flow controller (MFC) 51c, a storage tank 51d, and a valve 51e are provided in series from the upstream side. The downstream side of the valve 51e in the gas supply line 51b is connected to the gas introduction hole 36. The raw material gas supplied from the raw material gas supply source 51a is temporarily stored in the storage tank 51d before being supplied into the processing vessel 1, pressurized to a predetermined pressure in the storage tank 51d, and then supplied into the processing vessel 1. The supply and stop of the raw material gas from the storage tank 51d to the processing vessel 1 are performed by opening and closing the valve 51e. By temporarily storing the raw material gas in the storage tank 51d in this way, a relatively large flow rate of the raw material gas can be stably supplied into the processing vessel 1.

[0020] The reaction gas supply source 52a supplies a reaction gas (second processing gas) into the processing vessel 1 via the gas supply line 52b. In the following description, for example, NH3 is used as the reaction gas.

[0021] In the gas supply line 52b, a mass flow controller (MFC) 52c, a storage tank 52d, and a valve 52e are provided in series from the upstream side. The downstream side of the valve 52e in the gas supply line 52b is connected to the gas introduction hole 36. The reaction gas supplied from the reaction gas supply source 52a is temporarily stored in the storage tank 52d before being supplied into the processing vessel 1, pressurized to a predetermined pressure in the storage tank 52d, and then supplied into the processing vessel 1. The supply and stop of the reaction gas from the storage tank 52d to the processing vessel 1 are performed by opening and closing the valve 52e. By temporarily storing the reaction gas in the storage tank 52d in this way, a relatively large flow rate of the reaction gas can be stably supplied into the processing vessel 1.

[0022] The purge gas supply sources 53a, 54a supply an inert gas as a purge gas (third processing gas) into the processing vessel 1 via the gas supply lines 53b, 54b. In the following description, for example, N2 is used as the purge gas.

[0023] Flow controllers (MFCs) 53c, 54c and valves 53e, 54e are interposed in the gas supply lines 53b, 54b from the upstream side. The downstream side of valves 53e, 54e in the gas supply lines 53b, 54b is connected to the gas inlet hole 36. Purge gas supplied from purge gas supply sources 53a, 54a is supplied into the processing container 1. The supply and cessation of purge gas from purge gas supply sources 53a, 54a to the processing container 1 is performed by opening and closing valves 53e, 54e.

[0024] Furthermore, gas supply line 53b merges with gas supply line 51b downstream of valve 51e, downstream of valve 53e. In other words, the inert gas supplied from purge gas source 53a and flowing through gas supply line 53b functions as a carrier gas for the raw material gas. In addition, the inert gas flowing through gas supply line 53b functions as a counter gas to prevent the reaction gas flowing through gas supply line 52b from flowing into gas supply lines 51b and 53b.

[0025] Furthermore, gas supply line 54b merges with gas supply line 52b downstream of valve 52e, downstream of valve 54e. That is, the inert gas supplied from purge gas source 54a and flowing through gas supply line 54b functions as a carrier gas for the reaction gas. In addition, the inert gas flowing through gas supply line 54b functions as a counter gas to prevent the raw material gas flowing through gas supply line 51b from flowing into gas supply lines 52b and 54b.

[0026] Then, gas supply line 51b and gas supply line 52b merge downstream of the confluence of gas supply line 51b and gas supply line 53b, and downstream of the confluence of gas supply line 52b and gas supply line 54b, and are connected to the gas inlet hole 36.

[0027] Valves 51e to 54e are, for example, on-off valves that switch between fully open and fully closed. Furthermore, it is preferable that valves 51e to 54e are valves (ALD valves) capable of high-speed opening and closing required in the ALD process.

[0028] During processing, the partition member 17 and the mounting table 2 positioned at the processing location divide the inside of the processing container 1 into an upper space including the processing space 38 and a lower space on the back side of the mounting table 2. In addition, an annular gap 39 is formed between the upper surface of the cover member 22 of the mounting table 2 and the lower surface of the annular projection 34 of the shower plate 32. The processing space 38 is the space radially inward of the annular projection 34 and the annular gap 39 within the upper space of the processing container 1. The exhaust space 13a is the space radially outward of the annular projection 34 and the annular gap 39 within the upper space of the processing container 1. The control unit 9 adjusts the conductance of the annular gap 39 by adjusting the height of the mounting table 2 using the lifting mechanism 28, thereby adjusting the height (gap) between the upper surface of the cover member 22 of the mounting table 2 and the lower surface of the annular projection 34 of the shower plate 32.

[0029] Various gases (raw material gas, reaction gas, purge gas) supplied to the gas inlet 36 diffuse in the gas diffusion space 33 and are supplied into the processing space 38 from the gas discharge 35 of the shower plate 32.

[0030] Furthermore, the gas in the processing space 38 reaches the exhaust space 13a of the exhaust duct 13 via the annular gap 39, and is exhausted through the exhaust pipe 41 by the vacuum pump 44 of the exhaust section 4 from the exhaust port 13b of the exhaust duct 13. The lower space is purged by a purge gas supply mechanism (not shown). Therefore, the gas in the processing space 38 does not flow into the lower space.

[0031] In addition, the shower head 3 is provided with an exhaust line (second exhaust passage) 61 that communicates from the processing space 38 to the exhaust space 13a, separate from the annular gap 39. The upstream inlet 61a of the exhaust line 61 is provided on the lower surface of the annular projection 34. The downstream outlet 61b of the exhaust line 61 is provided on the lower surface of the top wall 14. Note that the location of the inlet 61a of the exhaust line 61 is not limited to this, and it may be provided on the side of the processing space 38. Furthermore, when the inlet 61a of the exhaust line 61 is provided in the processing space 38, it is preferable that it be provided radially outward from the outer edge (edge) of the substrate W. This allows the processing gas to be supplied uniformly to the substrate W from the gas discharge hole 35 of the shower plate 32, thereby improving the uniformity of the substrate processing. Furthermore, the location of the outlet 61b of the exhaust line 61 is not limited to this, and it may be provided on the side of the exhaust space 13a.

[0032] Furthermore, the exhaust line 61 is provided with an exhaust valve 62 for opening and closing the exhaust line 61. The exhaust valve 62 may be an on-off valve that switches between fully open and fully closed, an opening-degree control valve whose opening degree can be controlled, or a configuration that combines a flow controller (MFC) and an on-off valve; it is not limited to these. In addition, it is preferable that the exhaust valve 62, like the valves 51e to 54e, is an ALD valve capable of high-speed opening and closing required in the ALD process.

[0033] Figure 2 is an example of a view of the shower head 3 from below. As shown in Figure 2, multiple exhaust lines 61 (inlet 61a, outlet 61b) are provided at equal intervals in the circumferential direction (three in the example of Figure 2).

[0034] Figure 3 is an example of a diagram illustrating gas flow. In Figures 3(a) and 3(b), the gas flow is indicated by arrows.

[0035] Figure 3(a) is an example of a diagram showing the gas flow when the exhaust valve 62 is closed. By fully closing the exhaust valve 62, the exhaust line 61 is blocked. That is, the gas in the processing space 38 flows through the annular gap 39 to the exhaust space 13a. The gas that has flowed into the exhaust space 13a is then discharged outside the machine from the exhaust piping 41.

[0036] Figure 3(b) is an example of a diagram showing the gas flow when the exhaust valve 62 is opened. By opening the exhaust valve 62, gas flows through the exhaust line 61. That is, the gas in the processing space 38 flows to the exhaust space 13a through the annular gap 39 and the exhaust line 61. The gas that has flowed into the exhaust space 13a is then discharged outside the machine from the exhaust piping 41.

[0037] Returning to Figure 1, the substrate processing apparatus 100 is a capacitively coupled plasma apparatus, where the mounting table 2 serves as the lower electrode and the shower head 3 serves as the upper electrode. The mounting table 2, which serves as the lower electrode, is grounded via a capacitor (not shown).

[0038] The showerhead 3, which serves as the upper electrode, receives high-frequency power (hereinafter also referred to as "RF power") from the RF power supply unit 8. The RF power supply unit 8 includes a power supply line 81, a matching unit 82, and a high-frequency power supply 83. The high-frequency power supply 83 is a power source that generates high-frequency power. The high-frequency power has a frequency suitable for plasma generation. The frequency of the high-frequency power is, for example, within the range of 450 kHz to 100 MHz. The high-frequency power supply 83 is connected to the main body 31 of the showerhead 3 via the matching unit 82 and the power supply line 81. The matching unit 82 has a circuit for matching the output reactance of the high-frequency power supply 83 with the reactance of the load (upper electrode). Although the RF power supply unit 8 has been described as applying high-frequency power to the showerhead 3, which serves as the upper electrode, it is not limited to this. It may also be configured to apply high-frequency power to the mounting base 2, which serves as the lower electrode.

[0039] The substrate processing apparatus 100 also has pressure sensors 91 and 92. Pressure sensor 91 detects the pressure in the processing space 38 (pressure P1, described later). Since the conductance of the shower plate 32 is sufficiently large, the pressure in the gas diffusion space 33 and the pressure in the processing space 38 are approximately the same. For this reason, pressure sensor 91 may be installed in the gas diffusion space 33, and the pressure in the processing space 38 may be estimated from the pressure in the gas diffusion space 33. This eliminates the need to install a sensor in the processing space 38, thereby suppressing any impact on the substrate processing. Pressure sensor 92 detects the pressure in the exhaust space 13a (pressure P2, described later). The pressures detected by pressure sensors 91 and 92 are transmitted to the control unit 9.

[0040] The control unit 9 is, for example, a computer and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or auxiliary storage device and controls the operation of the substrate processing device 100. The control unit 9 may be located inside or outside the substrate processing device 100. If the control unit 9 is located outside the substrate processing device 100, the control unit 9 can control the substrate processing device 100 by communication means such as wired or wireless.

[0041] The control unit 9 adjusts the processing conditions for the substrate W based on the height (gap) of the annular gap 39 between the mounting base 2 and the shower head 3 (gas supply mechanism), the supply conditions (gas type, flow rate, etc.) of the processing gas supplied from the shower head 3 to the processing space 38, and the pressure inside the processing container 1 (pressure P1 in the processing space 38, pressure P2 in the exhaust space 13a).

[0042] [Insulating film deposition process using substrate processing equipment] Next, an example of the operation of the substrate processing apparatus 100 will be explained using Figures 4 to 6. Figure 4 is an example of a flowchart showing a substrate processing method. Figure 5 is an example of a diagram showing a recipe for the substrate processing method. Here, the substrate processing apparatus 100 will be explained using the case where a TiN film is deposited on a substrate W using the ALD process as an example. In Figure 5, "Step" indicates each step (process) of the ALD process. "Fill / Flow Time / Cycle" indicates the time for each process. "TiCl4" indicates the state of the raw material gas (raw material gas supplied from the raw material gas supply source 51a). "CounterN2for TiCl4" indicates the state of the purge gas on the raw material gas side (purge gas / carrier gas / counter gas supplied from the purge gas supply source 53a). "NH3" indicates the state of the reaction gas (reaction gas supplied from the reaction gas supply source 52a). "CounterN2for NH3" indicates the state of the purge gas on the reaction gas side (purge gas / carrier gas / counter gas supplied from the purge gas supply source 54a). "APC Vacuum" indicates the angle of the APC valve 42. "ALD Valve Vacuum" indicates the open / closed state and exhaust state of the exhaust valve 62 in the exhaust line 61.

[0043] In step S101, the substrate W is prepared. First, the substrate W is loaded into the processing container 1 of the substrate processing apparatus 100 shown in Figure 1. Specifically, the control unit 9 controls the lifting mechanism 28 to lower the mounting table 2 to the transport position (the position of the mounting table 2 shown by the dashed line) and opens the gate valve 12. Next, the substrate W is loaded into the processing container 1 via the loading / unloading port 11 by a transport arm (not shown) and placed on the mounting table 2, which has been temperature-controlled to a predetermined temperature by the heater 21. After the transport arm retracts from the loading / unloading port 11, the gate valve 12 is closed.

[0044] Next, the control unit 9 controls the lifting mechanism 28 to raise the mounting table 2 to the processing position (the position of the mounting table 2 shown by the solid line). This creates an annular gap 39 between the upper surface of the cover member 22 of the mounting table 2 and the lower surface of the annular projection 34 of the shower plate 32. The control unit 9 also controls the angle of the APC valve 42 to reduce the pressure inside the processing container 1 to a predetermined vacuum level using the exhaust unit 4 (vacuum pump 44). After the pressure reduction, the control unit 9 opens the valves 53e and 54e. This allows N2 gas (purge gas) to be supplied to the processing space 38 from the purge gas supply sources 53a and 54a.

[0045] In step S101, before starting the ALD process, both valves 51e and 52e are closed. While valve 51e is closed, the raw material gas supplied from the raw material gas supply source 51a fills the storage tank 51d. Similarly, while valve 52e is closed, the reaction gas supplied from the reaction gas supply source 52a fills the storage tank 52d. In step S101, the exhaust valve 62 may be closed or open.

[0046] Next, the control unit 9 deposits a desired film (TiN film) on the substrate W by repeating the ALD process (S102~S106). The ALD process consists of a cycle of supplying raw material gas (A), supplying purge gas (B), supplying reaction gas (C), and supplying purge gas (D), and this cycle is repeated a predetermined number of times.

[0047] In step S102, raw material gas is supplied to the processing space 38 (step A). ​​Specifically, the control unit 9 opens valve 51e. TiCl4 gas (raw material gas) is supplied into the processing space 38 from the raw material gas supply source 51a (TiCl4: Flow). The control unit 9 also controls the angle of the APC valve 42 to a predetermined angle W[°] and reduces the pressure in the exhaust space 13a to a predetermined vacuum level using the exhaust unit 4 (vacuum pump 44). The control unit 9 also closes the exhaust valve 62.

[0048] Valve 52e is closed, and the reaction gas supplied from the reaction gas source 52a fills the storage tank 52d (NH3: Fill). Valve 53e remains open (CounterN2 for TiCl4: Flow). Valve 54e also remains open (CounterN2 for NH3: Flow).

[0049] As a result, the raw material gas is adsorbed onto the surface of the substrate W, forming an adsorption layer of the raw material gas on the surface of the substrate W. In addition, closing the exhaust valve 62 increases the partial pressure of the raw material gas in the processing space 38, thereby improving the adsorption efficiency of the raw material gas. After a predetermined time T1 [ms] has elapsed, the control unit 9 closes the valve 51e, and the processing of the control unit 9 proceeds to the next step S103.

[0050] In step S103, purge gas is supplied to the processing space 38 (step B). Specifically, the control unit 9 opens valves 53e and 54e (CounterN2 for TiCl4: Flow) (CounterN2 for NH3: Flow). N2 gas (purge gas) is supplied to the processing space 38 from the purge gas supply sources 53a and 54a. The control unit 9 also controls the angle of the APC valve 42 to a predetermined angle X[°] and reduces the pressure inside the exhaust space 13a to a predetermined vacuum level using the exhaust unit 4 (vacuum pump 44). The control unit 9 also opens the exhaust valve 62.

[0051] Valve 51e is closed, and the raw material gas supplied from the raw material gas supply source 51a fills the storage tank 51d (TiCl4: Fill). Also, valve 52e is closed, and the reaction gas supplied from the reaction gas supply source 52a fills the storage tank 52d (NH3: Fill).

[0052] As a result, any excess raw material gas in the processing space 38 is purged by the purge gas. After a predetermined time T2 [ms] has elapsed, the control unit 9 proceeds to the next step S104.

[0053] In step S104, a reaction gas is supplied to the processing space 38 (step C). Specifically, the control unit 9 opens the valve 52e. NH3 gas (reaction gas) is supplied into the processing space 38 from the reaction gas supply source 52a (NH3: Flow). The control unit 9 also controls the angle of the APC valve 42 to a predetermined angle Y[°] and reduces the pressure in the exhaust space 13a to a predetermined vacuum level using the exhaust unit 4 (vacuum pump 44). The control unit 9 also closes the exhaust valve 62.

[0054] Valve 51e is closed, and the raw material gas supplied from the raw material gas supply source 51a fills the storage tank 51d (TiCl4: Fill). Valve 53e remains open (CounterN2 for TiCl4: Flow). Valve 54e also remains open (CounterN2 for NH3: Flow).

[0055] As a result, the raw material gas adsorbed on the surface of the substrate W reacts with the reaction gas to form a single layer of TiN. In addition, closing the exhaust valve 62 increases the partial pressure of the reaction gas in the processing space 38, thereby improving the reaction efficiency of the reaction gas. After a predetermined time T3 [ms] has elapsed, the control unit 9 closes the valve 52e, and the processing of the control unit 9 proceeds to the next step S105.

[0056] In step S105, purge gas is supplied to the processing space 38 (step D). Specifically, the control unit 9 opens valves 53e and 54e (CounterN2 for TiCl4: Flow) (CounterN2 for NH3: Flow). N2 gas (purge gas) is supplied to the processing space 38 from the purge gas supply sources 53a and 54a. The control unit 9 also controls the angle of the APC valve 42 to a predetermined angle Z[°] and reduces the pressure inside the exhaust space 13a to a predetermined vacuum level using the exhaust unit 4 (vacuum pump 44). The control unit 9 also opens the exhaust valve 62.

[0057] Valve 51e is closed, and the raw material gas supplied from the raw material gas supply source 51a fills the storage tank 51d (TiCl4: Fill). Also, valve 52e is closed, and the reaction gas supplied from the reaction gas supply source 52a fills the storage tank 52d (NH3: Fill).

[0058] As a result, any excess reaction gas in the processing space 38 is purged by the purge gas. After a predetermined time T2 [ms] has elapsed, the control unit 9 proceeds to the next step S106.

[0059] In step S106, the control unit 9 determines whether the number of cycles has reached a predetermined number of repetitions, considering the processes shown in steps S102 to S105 as one cycle. If the predetermined number of repetitions has not been reached (S106 - NO), the control unit 9 returns to step S102 and repeats the cycle from step S102 to step S105. If the predetermined number of repetitions is reached (S106 - YES), the control unit 9 terminates the process shown in Figure 4.

[0060] Subsequently, the control unit 9 controls the lifting mechanism 28 to lower the mounting platform 2 to the transport position (the position of the mounting platform 2 shown by the dashed line) and opens the gate valve 12. Next, the substrate W is transported out of the processing container 1 via the loading / unloading port 11 by a transport arm (not shown). After the transport arm has moved away from the loading / unloading port 11, the gate valve 12 is closed.

[0061] Here, let the flow rate of the gas controlled by the flow controllers (51c~54c) be the flow rate Q1. When the valves (51e~54e) are opened, let the flow rate of the gas supplied to the processing space 38 be the flow rate Q2. Also, let the flow rate of the gas flowing through the annular gap (first exhaust passage) 39 be the flow rate Qg. Let the flow rate of the gas flowing through the exhaust line (second exhaust passage) 61 be the flow rate Qv. Let the conductance of the annular gap (first exhaust passage) 39 be the conductance Cg, and the conductance of the exhaust line (second exhaust passage) 61 be the conductance Cv. In this case, the following relationships (1) and (2) exist.

[0062] Qv∝Cv / (Cv+Cg) ···(1) Q2 = Qv + Qg ... (2)

[0063] Here, if Cv >> Cg, then most of the gas discharged into the processing space 38 exhaust space 13a flows through the exhaust line 61. In other words, with the exhaust valve 62 open, the flow rate Qv of gas flowing through the exhaust line (second exhaust passage) 61 is greater than the flow rate Qg of gas flowing through the annular gap (first exhaust passage) 39 (Qv > Qg). In this case, the following relationship (3) holds.

[0064] Q2 ≈ Qv ···(3)

[0065] Furthermore, the pressure in the processing space 38 is defined as pressure P1. The pressure in the exhaust space 13a is defined as pressure P2.

[0066] Here, if the height (gap) between the upper surface of the cover member 22 of the mounting base 2 and the lower surface of the annular projection 34 of the shower plate 32 is sufficiently large, the pressure P1 in the processing space 38 and the pressure P2 in the exhaust space 13a will be approximately equal (P1 ≈ P2). In this case, the pressure P1 in the processing space 38 can be controlled by controlling the pressure P2 in the exhaust space 13a by controlling the APC valve 42.

[0067] Furthermore, when the height (gap) between the upper surface of the cover member 22 of the mounting base 2 and the lower surface of the annular projection 34 of the shower plate 32 decreases, a pressure difference is created between the pressure P1 in the processing space 38 and the pressure P2 in the exhaust space 13a. The flow rate Qg is proportional to the pressure difference (P1-P2). In this case as well, the exhaust flow rate Qg is controlled by controlling the pressure P2 in the exhaust space 13a by controlling the APC valve 42.

[0068] Then, as the height (gap) between the upper surface of the cover member 22 of the mounting base 2 and the lower surface of the annular projection 34 of the shower plate 32 decreases further and falls below a predetermined height, the upstream pressure P1 becomes more than twice the downstream pressure P2 (P1 ≥ 2P2), and the critical expansion condition is reached. When the critical expansion condition is reached, the exhaust flow rate Qg becomes dependent on the upstream pressure P1 and can no longer be controlled by the downstream pressure P2.

[0069] In other words, by reducing the gap of the annular gap 39, the adsorption efficiency of the raw material gas in step S102 can be improved, and the reaction efficiency in step S104 can be improved. On the other hand, in the purging process (S103, S105), if exhaust is performed only from the annular gap 39, it becomes difficult to exhaust the gas in the processing space 38 in a short time.

[0070] In contrast, in the substrate processing apparatus 100 shown in Figure 1, the exhaust valve 62 is opened during the purging process (S103, S105). This allows the gas in the processing space 38 to be exhausted in a short time. Furthermore, by controlling the APC valve 42 to control the pressure P2 in the exhaust space 13a, thereby suppressing the reaching of critical expansion conditions, the exhaust flow rate (Qg + Qv) can be controlled. That is, the flow rate Q2 (= Qg + Qv) can be controlled.

[0071] Figure 6 is a graph showing an example of pressure change. The horizontal axis represents time. The vertical axis represents each pressure (left vertical axis) and the opening and closing of the exhaust valve 62 (right vertical axis). The opening and closing of the exhaust valve 62 is shown with 0 representing fully closed and 1 representing fully open. Here, we show the case where the ALD process is performed with the exhaust valve 62 open (Ref) and the case where the ALD process is performed with the opening and closing of the exhaust valve 62 (Valve).

[0072] (P1_Ref) represents the pressure P1 in the processing space 38 when the ALD process is performed with the exhaust valve 62 open. (P2_Ref) represents the pressure P2 in the exhaust space 13a when the ALD process is performed with the exhaust valve 62 open. (2xP2) is twice the value of (P2_Ref) and is the threshold for whether or not the critical expansion condition is reached.

[0073] (P1_Valve) represents the pressure P1 in the processing space 38 when performing an ALD process that involves opening and closing the exhaust valve 62. (P2_Valve) represents the pressure P2 in the exhaust space 13a when performing an ALD process that involves opening and closing the exhaust valve 62. (Valve OPEN / CLOSE) is a graph showing the opening and closing of the exhaust valve 62.

[0074] Furthermore, the angle control of the APC valve 42 is controlled similarly whether the ALD process is performed with the exhaust valve 62 open (Ref) or whether the ALD process involves opening and closing the exhaust valve 62 (Valve). Therefore, the pressures of (P2_Ref) and (P2_Valve) match.

[0075] Furthermore, in the process of supplying the raw material gas (A) and the process of supplying the reaction gas (C), the exhaust valve 62 is closed whether the ALD process is performed with the exhaust valve 62 open (Ref) or with the ALD process involving opening and closing the exhaust valve 62 (Valve). Therefore, (P1_Ref) and (P1_Valve) have the same pressure. Note that in the areas shaded with dots, the critical expansion condition has been reached. That is, in steps S102 and S104, there are regions where the pressure P1 in the processing space 38 cannot be controlled by the APC valve 42.

[0076] In the purge gas supply process (B) and the purge gas supply process (D), if the ALD process is performed with the exhaust valve 62 open (Ref), the pressure P1 (P1_Ref) does not drop sufficiently, and the pressure P2 (P2_Ref) reaches the critical expansion condition (see the area with dot shading). That is, even if the pressure P2 (P2_Valve) is lowered, the purge efficiency is limited.

[0077] In contrast, when an ALD process involving the opening and closing of the exhaust valve 62 is performed in the purge gas supply process (B) and the purge gas supply process (D) (Valve), the ultimate vacuum level of pressure P1 (P1_Valve) can be lowered, thereby suppressing the reaching of critical expansion conditions and improving purging efficiency by lowering pressure P2 (P2_Valve).

[0078] In the examples shown in Figures 4 to 6, the exhaust valve 62 is opened in the raw material gas supply process (A) and the reaction gas supply process (C), and the exhaust valve 62 is also opened in the purge gas supply process (B) and the purge gas supply process (D). However, the process is not limited to this.

[0079] For example, when the pressure P1 in the processing space (processing area) 38 is twice or more the pressure P2 in the exhaust space (exhaust area) 13a (P1 ≥ 2P2), the control unit 9 opens the exhaust valve 62 and adjusts the flow rate of the exhaust line (second exhaust passage) 61. In this case, the opening degree of the exhaust valve 62 may also be adjusted. This suppresses reaching the critical expansion condition, and by controlling the APC valve 42 to control the pressure P2 in the exhaust space 13a, the exhaust flow rate Qg can be controlled, and the pressure P1 in the processing space 38 can be controlled.

[0080] For example, the control unit 9 opens the exhaust valve 62 and adjusts the flow rate of the exhaust line (second exhaust passage) 61 based on the pressure P1 of the processing space (processing area) 38 detected by the pressure sensor 91 and the pressure P2 of the exhaust space (exhaust area) 13a detected by the pressure sensor 92. In this case, the opening degree of the exhaust valve 62 may also be adjusted. This suppresses reaching the critical expansion condition, and by controlling the APC valve 42 to control the pressure P2 of the exhaust space 13a, the exhaust flow rate Qg can be controlled and the pressure P1 of the processing space 38 can be controlled.

[0081] The substrate processing method using the substrate processing apparatus 100 has been described above, but this disclosure is not limited to the embodiments described above, and various modifications and improvements are possible within the scope of the gist of this disclosure as described in the claims. [Explanation of Symbols]

[0082] W board 100 Substrate Processing Equipment 1. Processing container (processing chamber) 2. Mounting platform 3. Shower head (gas supply mechanism) 4. Exhaust section 5. Gas Supply Department 8 RF power supply section 9. Control Unit 13a Exhaust space (exhaust region) 24 Lifting mechanism 31 Main body 32 shower plates 33 Gas Diffusion Space 34 Annular projection 35 Gas discharge holes 36 Gas inlet 38 Processing space (processing area) 39. Annular gap (first exhaust passage) 41. Exhaust piping (third exhaust passage) 42 APC valve (pressure control unit) 43. On / off valve 44. Vacuum pump (exhaust pump) 61 Exhaust line (second exhaust passage) 62 Exhaust valve 91,92 Pressure Sensor

Claims

1. Processing room and A mounting platform is placed inside the aforementioned processing chamber on which the substrate is placed, A gas supply mechanism is positioned opposite the aforementioned mounting table and supplies processing gas to the substrate, A processing area formed between the mounting platform and the gas supply mechanism, The exhaust region from which exhaust is discharged by the exhaust section, A first exhaust passage is formed in the gap between the mounting base and the gas supply mechanism, through which the processed gas flows from the processing area to the exhaust area, A second exhaust passage is provided in the gas supply mechanism and is connected to the exhaust area so that the processed gas can flow from the processing area to the exhaust area. A third exhaust passage from which the processed gas is exhausted from the exhaust region, It comprises a control unit and, The control unit, The processing conditions for the substrate are adjusted based on the gap between the mounting table and the gas supply mechanism, the supply conditions of the processing gas supplied from the gas supply mechanism, and the pressure inside the processing chamber. Circuit board processing equipment.

2. The system further includes a lifting mechanism that raises and lowers the mounting platform to adjust the gap between the mounting platform and the gas supply mechanism. The substrate processing apparatus according to claim 1.

3. The second exhaust passage further has an exhaust valve, When the pressure in the processing area is twice or more the pressure in the exhaust area, the flow rate of the second exhaust passage is adjusted. A substrate processing apparatus according to claim 1.

4. When the aforementioned exhaust valve is opened, The flow rate of the processed gas flowing through the second exhaust passage is: A flow rate greater than that of the processed gas flowing through the first exhaust passage, A substrate processing apparatus according to claim 3.

5. The control unit, Based on the pressure detected by the first pressure sensor for detecting the pressure in the processing area and the pressure detected by the second pressure sensor for detecting the pressure in the exhaust area, the flow rate of the second exhaust passage is adjusted. A substrate processing apparatus according to claim 3.

6. The pressure within the exhaust region is Controlled by a pressure control unit provided in the third exhaust passage, A substrate processing apparatus according to claim 1.

7. The second exhaust passage further has an exhaust valve, The control unit, A first processing gas supply step of supplying a first processing gas to the processing area, A first purge gas supply step involves supplying a purge gas to the processing area to purge the first processing gas in the processing area, A second processing gas supply step for supplying a second processing gas to the processing area, A second purge gas supply step involves supplying purge gas to the processing area to purge the second processing gas in the processing area, and this constitutes one cycle, which is repeated. In the first purge gas supply step and the second purge gas supply step, the exhaust valve is opened. In the first processing gas supply step and the second processing gas supply step, the exhaust valve is closed. A substrate processing apparatus according to claim 1.

8. A substrate processing apparatus comprising: a processing chamber; a mounting table disposed within the processing chamber on which a substrate is placed; a gas supply mechanism disposed opposite to the mounting table and for supplying processing gas to the substrate; a processing area formed between the mounting table and the gas supply mechanism; an exhaust area from which exhaust gas is discharged by an exhaust section; a first exhaust passage formed in the gap between the mounting table and the gas supply mechanism, through which the processing gas flows from the processing area to the exhaust area; a second exhaust passage provided in the gas supply mechanism and connected to allow the processing gas to flow from the processing area to the exhaust area; and a third exhaust passage from which the processing gas is discharged from the exhaust area, wherein the substrate is processed, The processing conditions for the substrate are adjusted based on the gap between the mounting table and the gas supply mechanism, the supply conditions of the processing gas supplied from the gas supply mechanism, and the pressure inside the processing chamber. Substrate processing method.

9. The system further includes a lifting mechanism that raises and lowers the mounting platform to adjust the gap between the mounting platform and the gas supply mechanism. The substrate processing method according to claim 8.

10. The second exhaust passage further has an exhaust valve, When the pressure in the processing area is twice or more the pressure in the exhaust area, the flow rate of the second exhaust passage is adjusted. The substrate processing method according to claim 8.

11. When the aforementioned exhaust valve is opened, The flow rate of the processed gas flowing through the second exhaust passage is: A flow rate greater than that of the processed gas flowing through the first exhaust passage, The substrate processing method according to claim 10.

12. Based on the pressure detected by the first pressure sensor for detecting the pressure in the processing area and the pressure detected by the second pressure sensor for detecting the pressure in the exhaust area, the flow rate of the second exhaust passage is adjusted. The substrate processing method according to claim 10.

13. The pressure within the exhaust region is Controlled by a pressure control unit provided in the third exhaust passage, The substrate processing method according to claim 8.

14. The second exhaust passage further has an exhaust valve, A first processing gas supply step of supplying a first processing gas to the processing area, A first purge gas supply step involves supplying a purge gas to the processing area to purge the first processing gas in the processing area, A second processing gas supply step for supplying a second processing gas to the processing area, A second purge gas supply step involves supplying purge gas to the processing area to purge the second processing gas in the processing area, and this constitutes one cycle, which is repeated. In the first purge gas supply step and the second purge gas supply step, the exhaust valve is opened. In the first processing gas supply step and the second processing gas supply step, the exhaust valve is closed. The substrate processing method according to claim 8.

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