Substrate Processing Method and Substrate Processing System

Abstract

To provide a substrate processing method and a substrate processing system for selectively forming a metal silicide film on a bottom of a recess in a substrate having a recess.SOLUTION: A substrate processing method includes the steps of: preparing a substrate including a base portion having an epitaxial layer formed by epitaxial growth, and an insulating film formed on the base portion and having a through portion exposing the epitaxial layer; forming a silicon film on a surface of the epitaxial layer exposed from the through portion rather than a sidewall of the through portion; and forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than the sidewall of the through portion, and reacting the silicon film and the metal film to form a metal silicide film.SELECTED DRAWING: Figure 6

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses an oxide film removal method for removing a natural oxide film formed on the surface of silicon at the bottom of a pattern such as a contact hole or a trench. Patent Document 1 also discloses a contact formation method in which a metal film is formed after removing the natural oxide film, and the silicon at the bottom of the pattern is reacted with the metal film to form a contact at the bottom of the pattern.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One aspect of the present disclosure provides a substrate processing method and a substrate processing system for selectively forming a metal silicide film on the bottom of a recess in a substrate having a recess.

Means for Solving the Problems

[0005] A substrate processing method according to one aspect of the present disclosure includes a step of preparing a substrate having a base portion having an epitaxial layer formed by epitaxial growth and an insulating film formed on the base portion and having a through portion exposing the epitaxial layer, and a step of forming a silicon film on the surface of the epitaxial layer exposed from the through portion rather than on the side wall of the through portion. Selectively And a step of forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than on the side wall of the through portion, and reacting the silicon film and the metal film to form a metal silicide film. and the step of selectively forming the silicon film includes a step of supplying a silicon-containing gas to form the silicon film, and a step of supplying a halogen-containing gas to remove the silicon film formed on the sidewalls of the through holes. In the step of forming the silicon film, the silicon film formed at the bottom of the through holes is crystalline silicon, and the silicon film formed on the sidewalls of the through holes is amorphous silicon. In the step of removing the silicon film, the amorphous silicon formed on the sidewalls of the through holes is selectively removed 。

Advantages of the Invention

[0006] According to one aspect of the present disclosure, there can be provided a substrate processing method and a substrate processing system for selectively forming a metal silicide film on the bottom of a recess in a substrate having the recess.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding components may be denoted by the same reference numerals, and the description thereof may be omitted.

[0009] 〔Substrate Processing System〕 A substrate processing system according to an embodiment will be described with reference to FIG. 1. FIG. 1 is a schematic diagram showing a configuration example of the substrate processing system.

[0010] As shown in FIG. 1, the substrate processing system includes processing apparatuses 101 to 104, a vacuum transfer chamber 200, load lock chambers 301 to 303, an atmospheric transfer chamber 400, load ports 501 to 503, and a control unit 600.

[0011] The processing apparatuses 101 to 104 are each connected to the vacuum transfer chamber 200 via gate valves G11 to G14. The interiors of the processing apparatuses 101 to 104 are depressurized to a predetermined vacuum atmosphere, and a desired process is performed on a substrate W such as a wafer inside thereof. The processing apparatus 101 is an apparatus for removing a natural oxide film formed on the bottom of the concave portion of the substrate W. The processing apparatus 102 is an apparatus for selectively forming a silicon film (hereinafter also referred to as an Si film) on the bottom of the concave portion of the substrate W. The processing apparatus 103 is an apparatus for selectively forming a metal silicide film on the bottom of the concave portion of the substrate W by forming a metal film on the substrate W. The processing apparatus 104 may be the same as any one of the processing apparatuses 101 to 103 or may be an apparatus for performing another process. Note that the processing apparatuses 101 to 103 will be described later with reference to FIGS. 2 to 4.

[0012] The interior of the vacuum transfer chamber 200 is depressurized to a predetermined vacuum atmosphere. The vacuum transfer chamber 200 is provided with a transfer mechanism 201 capable of transferring the substrate W in a depressurized state. The transfer mechanism 201 transfers the substrate W to the processing apparatuses 101 to 104 and the load lock chambers 301 to 303. The transfer mechanism 201 has, for example, two transfer arms 202a and 202b.

[0013] The load lock chambers 301 to 303 are each connected to the vacuum transfer chamber 200 via gate valves G21 to G23 and are connected to the atmospheric transfer chamber 400 via gate valves G31 to G33. The interiors of the load lock chambers 301 to 303 can be switched between an atmospheric atmosphere and a vacuum atmosphere.

[0014] The inside of the atmospheric transfer chamber 400 is in an atmospheric environment, and for example, a downflow of clean air is formed. Inside the atmospheric transfer chamber 400, an aligner 401 for aligning the substrate W is provided. Further, a transfer mechanism 402 is provided in the atmospheric transfer chamber 400. The transfer mechanism 402 transfers the substrate W to the load lock chambers 301 to 303, the carriers C of the load ports 501 to 503 described later, and the aligner 401.

[0015] The load ports 501 to 503 are provided on the long side wall surface of the atmospheric transfer chamber 400. The load ports 501 to 503 are attached with the carrier C in which the substrate W is accommodated or an empty carrier C. As the carrier C, for example, a FOUP (Front Opening Unified Pod) can be used.

[0016] The control unit 600 controls each part of the substrate processing system. For example, the control unit 600 executes operations of the processing apparatuses 101 to 104, operations of the transfer mechanisms 201 and 402, opening and closing of the gate valves G11 to G14, G21 to G23, G31 to G33, switching of the atmosphere in the load lock chambers 301 to 303, etc. The control unit 600 may be, for example, a computer.

[0017] Note that the configuration of the substrate processing system is not limited to this. The substrate processing system may have a multi-wafer apparatus that processes a plurality of substrates W in one processing apparatus, or may have a configuration in which a vacuum transfer chamber and a multi-wafer apparatus are connected via a gate valve, or may have a configuration in which a plurality of vacuum transfer apparatuses are connected.

[0018] 〔Processing Apparatus 101〕 Next, the processing apparatus 101 will be described with reference to FIG. 2. FIG. 2 is an example of a schematic diagram showing a configuration example of the processing apparatus 101. The processing apparatus 101 is an apparatus for removing a natural oxide film formed on the bottom of the concave portion of the substrate W in a processing container 1 in a reduced pressure state.

[0019] As shown in FIG. 2, the processing apparatus 101 includes a processing chamber 1, a mounting stage 2, a shower head 3, an exhaust unit 4, a gas supply mechanism 5, an RF power supply unit 8, and a control unit 9.

[0020] The processing chamber 1 is made of a metal such as aluminum and has a substantially cylindrical shape. The processing chamber 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 chamber 1, and the inlet / outlet 11 is opened and closed by a gate valve 12 (gate valve G11 shown in FIG. 1). An annular exhaust duct 13 having a rectangular cross-section is provided on the upper part of the main body of the processing chamber 1. A slit 13a is formed along the inner peripheral surface of 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 chamber 1 via an insulator member 16. The space between the exhaust duct 13 and the insulator member 16 is hermetically sealed by a seal ring 15. The partitioning member 17 partitions the inside of the processing chamber 1 vertically when the mounting stage 2 (and the cover member 22) rises to a processing position described later.

[0021] The mounting stage 2 horizontally supports the substrate W in the processing chamber 1. The mounting stage 2 is formed in a disk shape having a size corresponding to the substrate W and is supported by a support member 23. The mounting stage 2 is made of a ceramic material such as AlN or a metal material such as aluminum or nickel alloy, and a heater 21 for heating the substrate W is embedded therein. The heater 21 is supplied with power from a heater power supply (not shown) and generates heat. Then, 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 stage 2, so that the substrate W is controlled to a predetermined temperature. The mounting stage 2 may be provided with an electrostatic chuck for electrostatically attracting the substrate W. By providing the electrostatic chuck, the substrate W is electrostatically attracted to the surface of the mounting stage 2, so that the temperature of the substrate W can be controlled with high precision. Further, the mounting stage 2 may form a flow path therein and allow a temperature control refrigerant from the outside to flow through and circulate. The mounting stage 2 is provided with a cover member 22 made of a ceramic such as alumina so as to cover the outer peripheral region and the side surface of the upper surface.

[0022] On the bottom surface of the mounting table 2, a support member 23 for supporting the mounting table 2 is provided. The support member 23 extends downward from the center of the bottom surface of the mounting table 2 through a hole formed in the bottom wall of the processing container 1 and extends below the processing container 1, and its lower end is connected to the lifting mechanism 24. The lifting mechanism 24 causes the mounting table 2 to move up and down via the support member 23 between the processing position shown in FIG. 1 and the transfer position where the substrate W can be transferred shown by the two-dot chain line below it. Below the processing container 1 of the support member 23, a flange portion 25 is attached, and between the bottom surface of the processing container 1 and the flange portion 25, a bellows 26 is provided that partitions the atmosphere inside the processing container 1 from the outside air and expands and contracts as the mounting table 2 moves up and down.

[0023] Near the bottom surface of the processing container 1, three (only two are shown) substrate support pins 27 are provided so as to protrude upward from the lifting plate 27a. The substrate support pins 27 move up and down via the lifting plate 27a by a lifting mechanism 28 provided below the processing container 1. The substrate support pins 27 are inserted into through holes 2a provided in the mounting table 2 in the transfer position and can project and retract with respect to the upper surface of the mounting table 2. By moving the substrate support pins 27 up and down, the substrate W is transferred between the transfer mechanism (not shown) and the mounting table 2.

[0024] The shower head 3 supplies the processing gas in a shower form into the processing vessel 1. The shower head 3 is made of metal, is provided so as to face the mounting table 2, and has substantially the same diameter as the mounting table 2. The shower head 3 has a main body portion 31 fixed to the top wall 14 of the processing vessel 1 and a shower plate 32 connected below the main body portion 31. A gas diffusion space 33 is formed between the main body portion 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 center of the top wall 14 of the processing vessel 1 and the main body portion 31. An annular protrusion 34 protruding downward is formed at the peripheral edge of the shower plate 32. Gas discharge holes 35 are formed in the flat surface inside the annular protrusion 34. In a state where the mounting table 2 is at the processing position, a processing space 38 is formed between the mounting table 2 and the shower plate 32, and an annular gap 39 is formed with the upper surface of the cover member 22 and the annular protrusion 34 being close to each other.

[0025] The exhaust section 4 exhausts the inside of the processing vessel 1. The exhaust section 4 has an exhaust pipe 41 connected to the exhaust port 13b and an exhaust mechanism 42 having a vacuum pump, a pressure control valve, etc. connected to the exhaust pipe 41. During processing, the gas in the processing vessel 1 reaches the exhaust duct 13 through the slit 13a, and is exhausted by the exhaust mechanism 42 through the exhaust pipe 41 from the exhaust duct 13.

[0026] The gas supply mechanism 5 supplies the processing gas into the processing vessel 1. The gas supply mechanism 5 has a gas supply section 50a.

[0027] The gas supply section 50a supplies the etching gas into the processing vessel 1 through a gas supply line 50b. As the etching gas, a halogen-containing gas (for example, C4F8 gas, HF gas, CF4 gas), NH3 gas, H2 gas, an inert gas, etc. are supplied into the processing vessel 1.

[0028] A flow controller 50c and a valve 50d are provided in the gas supply line 50b in series from the upstream side. The downstream side of the valve 50d in the gas supply line 50b is connected to the gas introduction hole 36. The gas supplied from the gas supply unit 50a is supplied into the processing chamber 1. The supply and stop of the gas from the gas supply unit 50a to the processing chamber 1 are performed by opening and closing the valve 50d.

[0029] The processing apparatus 101 is a capacitively coupled plasma apparatus, in which the mounting table 2 serves as a lower electrode and the shower head 3 serves as an upper electrode. The mounting table 2 serving as the lower electrode is grounded via a capacitor (not shown).

[0030] The shower head 3 serving as the upper electrode has high-frequency power (hereinafter also referred to as "RF power") applied thereto by 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 source 83. The high-frequency power source 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, in the range of 450 KHz to 100 MHz. The high-frequency power source 83 is connected to the main body 31 of the shower head 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 source 83 and the reactance of the load (upper electrode). Although the RF power supply unit 8 has been described as applying high-frequency power to the shower head 3 serving as the upper electrode, the present invention is not limited thereto. A configuration in which high-frequency power is applied to the mounting table 2 serving as the lower electrode may also be employed.

[0031] The control unit 9 is, for example, a computer, and includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the processing device 101. The control unit 9 may be provided inside the processing device 101 or outside it. When the control unit 9 is provided outside the processing device 101, the control unit 9 can control the processing device 101 by means of communication means such as wired or wireless.

[0032] 〔Processing device 102〕 Next, the processing device 102 will be described with reference to FIG. 3. FIG. 3 is an example of a schematic diagram showing a configuration example of the processing device 102. The processing device 102 is a device for selectively forming a Si film on the bottom of the concave portion of the substrate W in the processing container 1 in a reduced pressure state.

[0033] As shown in FIG. 3, the processing device 102 includes a processing container 1, a mounting table 2, a shower head 3, an exhaust unit 4, a gas supply mechanism 5, and a control unit 9. In the processing device 102, the description of the configuration overlapping with that of the processing device 101 (see FIG. 2) will be omitted.

[0034] The gas supply mechanism 5 supplies a processing gas into the processing container 1. The gas supply mechanism 5 includes a silicon-containing gas supply unit 51a, a halogen-containing gas supply unit 52a, and an inert gas supply unit 55a.

[0035] The silicon-containing gas supply unit 51a supplies a silicon-containing gas into the processing container 1 via a gas supply line 51b. As the silicon-containing gas, for example, a gas containing at least one of gases such as SiH4 gas, Si2H6 gas, SiH2Cl2 gas, Si3H8 gas, Si4H 10 A gas such as gas can be used.

[0036] A flow controller 51c and a valve 51d are provided in the gas supply line 51b in series from the upstream side. The downstream side of the valve 51d in the gas supply line 51b is connected to the gas introduction hole 36 via the gas supply line 57. The silicon-containing gas supplied from the silicon-containing gas supply section 51a is supplied into the processing vessel 1. The supply and stop of the silicon-containing gas from the silicon-containing gas supply section 51a to the processing vessel 1 are performed by opening and closing the valve 51d.

[0037] The halogen-containing gas supply section 52a supplies a halogen-containing gas into the processing vessel 1 via the gas supply line 52b. As the halogen-containing gas, for example, a gas containing at least one of gases such as Cl2 gas, HBr gas, and ClF3 gas can be used.

[0038] A flow controller 52c and a valve 52d are provided in the gas supply line 52b in series from the upstream side. The downstream side of the valve 52d in the gas supply line 52b is connected to the gas introduction hole 36 via the gas supply line 57. The halogen-containing gas supplied from the halogen-containing gas supply section 52a is supplied into the processing vessel 1. The supply and stop of the halogen-containing gas from the halogen-containing gas supply section 52a to the processing vessel 1 are performed by opening and closing the valve 52d.

[0039] The inert gas supply section 55a supplies an inert gas into the processing vessel 1 via the gas supply line 55b. As the inert gas, for example, Ar gas or the like can be used.

[0040] A flow controller 55c and a valve 55d are provided in the gas supply line 55b in series from the upstream side. The downstream side of the valve 55d in the gas supply line 55b is connected to the gas introduction hole 36 via the gas supply line 57. The inert gas supplied from the inert gas supply section 55a is supplied into the processing vessel 1. The supply and stop of the inert gas from the inert gas supply section 55a to the processing vessel 1 are performed by opening and closing the valve 55d.

[0041] 〔Processing apparatus 103〕 Next, the processing apparatus 103 will be described with reference to FIG. 4. FIG. 4 is an example of a schematic diagram showing a configuration example of the processing apparatus 103. The processing apparatus 103 is an apparatus for forming a metal film on a substrate W in a processing container 1 under a reduced pressure state. By forming the metal film, a metal silicide film is selectively formed on the bottom of the concave portion of the substrate W.

[0042] As shown in FIG. 4, the processing apparatus 103 includes a processing container 1, a mounting table 2, a shower head 3, an exhaust unit 4, a gas supply mechanism 5, an RF power supply unit 8, and a control unit 9. In the processing apparatus 102, the description of the configuration overlapping with the processing apparatus 101 (see FIG. 2) will be omitted.

[0043] The gas supply mechanism 5 supplies a processing gas into the processing container 1. The gas supply mechanism 5 includes a metal-containing gas supply unit 53a, a reducing gas supply unit 54a, and an inert gas supply unit 56a.

[0044] The metal-containing gas supply unit 53a supplies a metal-containing gas into the processing container 1 via a gas supply line 53b. As the metal-containing gas, for example, a gas containing at least one of gases such as TiCl4 gas and TiBr4 gas can be used.

[0045] A flow controller 53c and a valve 53d are provided in the gas supply line 53b from the upstream side. The downstream side of the valve 53d in the gas supply line 53b is connected to a gas introduction hole 36 via a gas supply line 57. The metal-containing gas supplied from the metal-containing gas supply unit 53a is supplied into the processing container 1. The supply and stop of the metal-containing gas from the metal-containing gas supply unit 53a to the processing container 1 are performed by opening and closing the valve 53d.

[0046] The reducing gas supply unit 54a supplies a reducing gas into the processing container 1 via a gas supply line 54b. As the reducing gas, for example, H2 gas or the like can be used.

[0047] A flow controller 54c and a valve 54d are provided in the gas supply line 54b in series from the upstream side. The downstream side of the valve 54d in the gas supply line 54b is connected to the gas introduction hole 36 via the gas supply line 57. The reducing gas supplied from the reducing gas supply section 54a is supplied into the processing vessel 1. The supply and stop of the reducing gas from the reducing gas supply section 54a to the processing vessel 1 are performed by opening and closing the valve 54d.

[0048] The inert gas supply section 56a supplies an inert gas into the processing vessel 1 via the gas supply line 56b. As the inert gas, for example, Ar gas or the like can be used.

[0049] A flow controller 56c and a valve 56d are provided in the gas supply line 56b in series from the upstream side. The downstream side of the valve 56d in the gas supply line 56b is connected to the gas introduction hole 36 via the gas supply line 57. The inert gas supplied from the inert gas supply section 56a is supplied into the processing vessel 1. The supply and stop of the inert gas from the inert gas supply section 56a to the processing vessel 1 are performed by opening and closing the valve 56d.

[0050] 〔Substrate processing method〕 Next, a substrate processing method of the substrate processing system according to an embodiment will be described with reference to FIGS. 5 and 6. FIG. 5 is an example of a flowchart for explaining the substrate processing method of the substrate processing system. FIG. 6 is an example of a cross-sectional view of the substrate W in each step.

[0051] In step S101, the control unit 600 prepares the substrate W. The control unit 600 controls the transfer mechanism 402 and the gate valve G31 to transfer the substrate W accommodated in the carrier C to the load lock chamber 301 in the atmospheric atmosphere through the atmospheric transfer chamber 400. The control unit 600 controls the load lock chamber 301 to decompress the interior of the load lock chamber 301 to a vacuum atmosphere. The control unit 600 controls the transfer mechanism 201 and the gate valves G21 and G11 to transfer the substrate W from the load lock chamber 301 to the processing apparatus 101 and place the substrate W on the mounting table 2 of the processing apparatus 101. Then, the control unit 9 of the processing apparatus 101 controls the elevating mechanism 24 to raise the mounting table 2 from the transfer position to the processing position.

[0052] Here, FIG. 6(a) shows an example of the prepared substrate W. The substrate W has a base portion 700 and an insulating film 710 formed on the base portion 700. The base portion 700 is formed of, for example, Si or SiGe. The insulating film 710 is formed of, for example, SiN or SiO2. A through-hole 720 is formed in the insulating film 710 so as to expose the surface of the base portion 700. That is, a concave portion is formed on the surface of the substrate W, and the surface of the base portion 700 is exposed at the bottom of the concave portion.

[0053] The base portion 700 has an epitaxial layer 701 which is a crystalline silicon film formed by epitaxial growth. For example, in a Fin-type channel field effect transistor, the source and drain are formed by epitaxially growing Si or SiGe. In addition, a native oxide film 702 is formed on the surface of the base portion 700 (the bottom of the concave portion) exposed from the through-hole 720.

[0054] In step S102, the control unit 600 controls the processing apparatus 101 to remove the native oxide film 702 formed on the surface of the base portion 700 exposed from the through-hole 720.

[0055] The processing device 101 applies high-frequency power to the showerhead 3 serving as the upper electrode by, for example, the RF power supply unit 8, and supplies an etching gas (e.g., C4F8 gas), an inert gas, etc. into the processing chamber 1 from the gas supply unit 50a, thereby performing plasma etching on and removing the native oxide film 702 of the substrate W. Further, the processing device 101 chemically etches and removes the native oxide film 702 of the substrate W by, for example, supplying an etching gas (e.g., HF gas) and a reactive gas (e.g., NH3 gas) into the processing chamber 1 from the gas supply unit 50a. Note that the method for removing the native oxide film 702 performed by the processing device 101 is not limited to these.

[0056] Here, FIG. 6(b) shows an example of the substrate W from which the native oxide film 702 has been removed. By removing the native oxide film 702, the surface of the underlying portion 700 exposed from the through-hole 720 exposes the surface of the epitaxial layer 701, which is a crystalline silicon film.

[0057] In step S103, the control unit 600 vacuum-transfers the substrate W from the processing device 101 to the processing device 102. The control unit 9 of the processing device 101 controls the elevating mechanism 24 to lower the mounting stage 2 from the processing position to the transfer position. The control unit 600 controls the transfer mechanism 201 and the gate valves G11, G12 to transfer the substrate W from the processing device 101 to the processing device 102 and mount the substrate W on the mounting stage 2 of the processing device 102. Then, the control unit 9 of the processing device 102 controls the elevating mechanism 24 to raise the mounting stage 2 from the transfer position to the processing position.

[0058] In step S104, the control unit 600 controls the processing device 102 to form a Si film on the substrate W.

[0059] The processing device 102, for example, supplies a silicon-containing gas (e.g., monosilane (SiH4) gas, disilane (Si2H6) gas, trisilane (Si3H8) gas, tetrasilane (Si4H 10By supplying a gas, a monochlorosilane (SiH3Cl) gas, a dichlorosilane (SiH2Cl2) gas, a trichlorosilane (SiHCl3) gas, a silicon tetrachloride (SiCl4) gas, or a hexachlorodisilane (Si2Cl6) gas, which is a chlorine-containing compound gas, an Si film is formed on the substrate W.

[0060] Here, FIG. 6(c) shows an example of the substrate W on which an Si film is formed by the treatment of the processing apparatus 102.

[0061] An epitaxial layer 701 formed of Si or SiGe is formed at the bottom of the recess. Therefore, a crystalline silicon film is formed by epitaxial growth from the epitaxial layer 701 at the bottom of the recess. Thereby, the film thickness of the epitaxial layer 701 can be increased. On the other hand, an amorphous silicon film 703 is formed on the upper surface of the insulating film 710 formed of SiN or SiO2 and the side walls of the through holes 720. In this way, due to the difference in the base on which the Si film is formed, a crystalline silicon film (epitaxial layer 701) can be formed at the bottom of the recess, and an amorphous silicon film 703 can be formed on the side surface and the upper surface of the recess.

[0062] FIG. 7 is an example of a graph showing the film formation result of the Si film in the process shown in step S104. FIG. 7(a) shows the case where an Si film is formed on an Si base, and FIG. 7(b) shows the case where an Si film is formed on an SiGe base. Further, with the horizontal axis representing the depth (nm) and the vertical axis representing the elemental concentration (At%), EDX analysis was performed to confirm whether an Si film was formed.

[0063] The Si film was formed under the film formation conditions of a stage temperature of 500 to 600 ° C., a pressure of 1 to 10 Torr, 10 to 100 sccm of Si2H6 gas as a silicon-containing gas, and 100 to 5000 sccm of Ar gas as an inert gas.

[0064] From the results of FIGS. 7(a) and 7(b), it was confirmed that an Si film can be formed on both Si and SiGe substrates.

[0065] Also, when using Si2H6 gas as the silicon-containing gas, by controlling the temperature of the substrate W during the formation of the Si film from 400°C to 580°C, a crystalline silicon film is formed on the surface of the epitaxial layer 701 (the bottom of the recess), and an amorphous silicon film is formed on the upper surface of the insulating film 710 and the side walls of the through-hole 720 (the side walls of the recess). Also, when using Si4H 10 gas as the silicon-containing gas, by controlling the temperature of the substrate W from 350°C to 480°C, a crystalline silicon film is formed on the surface of the epitaxial layer 701 (the bottom of the recess), and an amorphous silicon film is formed on the upper surface of the insulating film 710 and the side walls of the through-hole 720 (the side walls of the recess).

[0066] Returning to FIGS. 5 and 6, in step S105, the control unit 600 controls the processing apparatus 102 to selectively etch the amorphous silicon film 703.

[0067] The processing apparatus 102 chemically etches the Si film formed on the substrate W, for example, by supplying a halogen-containing gas (e.g., Cl2 gas, HBr gas, ClF3 gas) from the halogen-containing gas supply unit 52a into the processing chamber 1.

[0068] Here, the etching rates of the amorphous silicon film and the crystalline silicon film will be described with reference to FIG. 8. FIG. 8 is a graph showing an example of the etching rates in the amorphous silicon film and the crystalline silicon film. The horizontal axis represents the reciprocal of the temperature 1000 / T [1 / °C]. The vertical axis represents the etching rate [nm / min]. Also, the etching rate in the amorphous silicon film (a-Si) is indicated by a solid line, and the etching rate in the crystalline silicon film (Epi Si) is indicated by a dashed line.

[0069] Here, an amorphous silicon film and a crystalline silicon film were chemically etched using Cl2 gas as the halogen-containing gas. In the example shown in the graph of FIG. 8, the etching rate of the amorphous silicon film is about 10 times that of the crystalline silicon film. Thereby, the processing apparatus 102 can selectively etch the amorphous silicon film 703.

[0070] Here, FIG. 6(d) shows an example of a substrate W on which the amorphous silicon film 703 has been selectively etched by the processing of the processing apparatus 102. The amorphous silicon film 703 formed on the upper surface of the insulating film 710 and the side walls of the through-holes 720 is etched.

[0071] In this way, by the processes of step S104 and step S105, a crystalline silicon film can be selectively formed on the bottom of the recess.

[0072] Although the steps of supplying the silicon-containing gas shown in step S104 and the step of supplying the halogen-containing gas shown in step S105 have been described as being performed sequentially, the present invention is not limited thereto.

[0073] For example, a configuration in which the silicon-containing gas and the halogen-containing gas are supplied simultaneously may be employed. Thereby, while suppressing the formation of the amorphous silicon film 703 on the upper surface of the insulating film 710 and the side walls of the through-holes 720, a crystalline silicon film (epitaxial layer 701) can be formed on the bottom of the recess.

[0074] Further, a configuration in which the step of supplying the silicon-containing gas shown in step S104 and the step of supplying the halogen-containing gas shown in step S105 are repeated may be employed. Thereby, a crystalline silicon film can be selectively formed on the bottom of the recess.

[0075] In step S106, the control unit 600 vacuum-transfers the substrate W from the processing apparatus 102 to the processing apparatus 103. The control unit 9 of the processing apparatus 102 controls the elevating mechanism 24 to lower the mounting table 2 from the processing position to the transfer position. The control unit 600 controls the transfer mechanism 201 and the gate valves G12 and G13 to transfer the substrate W from the processing apparatus 102 to the processing apparatus 103 and mount the substrate W on the mounting table 2 of the processing apparatus 103. Then, the control unit 9 of the processing apparatus 103 controls the elevating mechanism 24 to raise the mounting table 2 from the transfer position to the processing position.

[0076] In step S107, the control unit 600 controls the processing apparatus 103 to form a metal film (Ti film) on the substrate W.

[0077] The processing apparatus 103 supplies, for example, a metal-containing gas (e.g., TiCl4 gas, TiBr4 gas) into the processing chamber 1 from the metal-containing gas supply unit 53a, supplies a reducing gas (e.g., H2 gas) into the processing chamber 1 from the reducing gas supply unit 54a, and supplies an inert gas (e.g., Ar gas) into the processing chamber 1 from the inert gas supply unit 56a. Then, high-frequency power is applied to the shower head 3 serving as the upper electrode by the RF power supply unit 8 to generate plasma, and the generated plasma is irradiated onto the substrate W, so that a metal film (Ti film) is formed on the substrate W by a CVD (chemical vapor deposition) reaction.

[0078] Here, at the bottom of the recess, a metal film (e.g., Ti film) is formed on the epitaxial layer 701. The metal film reacts with the epitaxial layer 701 to self-alignedly form a metal silicide film (TiSi film) 730.

[0079] Also, the metal film (Ti film) formed on the upper surface of the insulating film 710 and the side walls of the through-holes 720 is self-etched by TiCl4 gas. Therefore, the formation of the metal film (Ti film) on the upper surface of the insulating film 710 and the side walls of the through-holes 720 is suppressed.

[0080] Note that although the metal film has been described as a Ti film and the metal silicide film as a TiSi film, the present invention is not limited thereto.

[0081] After the processing is completed, the control unit 600 vacuum-transfers the substrate W from the processing apparatus 103 to the load lock chamber 301. The control unit 9 of the processing apparatus 103 controls the elevating mechanism 24 to lower the mounting table 2 from the processing position to the transfer position. The control unit 600 controls the transfer mechanism 201 and the gate valves G13 and G21 to transfer the substrate W from the processing apparatus 103 to the load lock chamber 301. The control unit 600 controls the load lock chamber 301 to make the inside of the load lock chamber 301 into an atmospheric atmosphere. The control unit 600 controls the transfer mechanism 402 and the gate valve G31 to transfer the substrate W from the load lock chamber 301 to the carrier C via the atmospheric transfer chamber 400 and accommodate the substrate W in the carrier C.

[0082] According to the substrate processing method of the substrate processing system according to an embodiment, in the substrate W having recesses, a metal silicide film 730 can be selectively formed on the bottom of the recesses. Further, according to the substrate processing method of the substrate processing system, the amorphous silicon film 703 formed on the upper surface of the insulating film 710 and the side walls of the through-holes 720 can be removed by the processing in step S105. Thereby, when a metal film is formed on the substrate W by the processing in step S107, it is possible to prevent a metal silicide film from being formed on the upper surface of the insulating film 710 and the side walls of the through-holes 720. Also, a metal silicide film 730 can be suitably formed even at the bottom of the recesses having a high aspect ratio.

[0083] Further, according to the substrate processing method of the substrate processing system, the film thickness of the crystalline silicon film (epitaxial layer 701) formed at the bottom of the recesses can be increased by the processing in step S104 and step S105. Thereby, the film thickness of the metal silicide film 730 formed by the reaction between the metal film and the crystalline silicon film (epitaxial layer 701) can be increased by the processing in step S107.

[0084] Thus, according to the substrate processing method of the substrate processing system, it is possible to increase the film thickness of the metal silicide film 730 formed on the bottom of the recess of the substrate W, and prevent the formation of the metal silicide film on the upper surface of the insulating film 710 and the side walls of the through holes 720.

[0085] Further, for example, when the epitaxial layer 701 is the source / drain of a Fin-type channel field effect transistor, a contact which is the metal silicide film 730 can be selectively formed on the bottom of the recess, and the film thickness can be controlled (increased).

[0086] Further, for example, the present embodiment can also be applied to a structure having a recess in the lateral direction or a structure having a through hole such as a Gate-All-Around type field effect transistor.

[0087] In addition, in the formation of the Si film, an embodiment of forming the film without using plasma has been described, but this is not the only case. For example, the RF power supply unit 8 of the processing apparatus 101 can be applied to the processing apparatus 102 and used to form the Si film by capacitively coupled plasma. Further, without being limited to capacitively coupled plasma, for example, inductively coupled plasma (ICP), microwave-excited surface wave plasma (SWP), electron cyclotron resonance plasma (ECP), or helicon wave-excited plasma (HWP) etc. can be applied.

[0088] Also, even when the material of the base portion 700 is mixed such that the bottom of one of the plurality of recesses is Si and the bottom of the other recess is SiGe, a crystalline silicon film can be selectively formed on the bottom of each recess, and the formed crystalline silicon film can be reacted with the metal film, so that the film thickness variation of the metal silicide film 730 can be suppressed.

[0089] As described above, embodiments of the substrate processing system and the like have been described, but the present disclosure is not limited to the above embodiments and the like, and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims.

Description of Reference Numerals

[0090] 101 Processing device (first processing device) 102 Processing device (second processing device) 103 Processing device (third processing device) 200 Vacuum transfer chamber 201 Transfer mechanism 600 Control unit 700 Substrate portion 701 Epitaxial layer (silicon film, crystalline silicon film) The natural oxide film 703 Amorphous silicon film 710 Insulating film 720 Through portion 730 Metal silicide film W substrate

Claims

1. Preparing a substrate having a base portion with an epitaxial layer formed by epitaxial growth and an insulating film formed on the base portion and having a through-hole exposing the epitaxial layer; Selectively forming a silicon film on the surface of the epitaxial layer exposed from the through-hole rather than on the sidewall of the through-hole; Forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than on the sidewall of the through-hole, and reacting the silicon film with the metal film to form a metal silicide film; The step of selectively forming the silicon film comprises: Supplying a silicon-containing gas to form a silicon film; Supplying a halogen-containing gas to remove the silicon film formed on the sidewall of the through-hole; In the step of forming the silicon film, the silicon film formed at the bottom of the through-hole is crystalline silicon, and the silicon film formed on the sidewall of the through-hole is amorphous silicon; In the step of removing the silicon film, the amorphous silicon formed on the sidewall of the through-hole is selectively removed; A substrate processing method.

2. Preparing a substrate having a base portion with an epitaxial layer formed by epitaxial growth and an insulating film formed on the base portion and having a through-hole exposing the epitaxial layer; Selectively forming a silicon film on the surface of the epitaxial layer exposed from the through-hole rather than on the sidewall of the through-hole; Forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than on the sidewall of the through-hole, and reacting the silicon film with the metal film to form a metal silicide film; The step of selectively forming the silicon film comprises: By simultaneously supplying a silicon-containing gas and a halogen-containing gas, the amorphous silicon formed on the sidewall of the through-hole is removed, and crystalline silicon is selectively formed at the bottom of the through-hole; A substrate processing method.

3. The step of forming the silicon film comprises: Repeating the step of forming the silicon film and the step of removing the silicon film; The substrate processing method according to Claim 1.

4. The silicon-containing gas is SiH ４ gas, Si ２ H ６ gas, SiH ２ Cl ２ gas, Si ３ H ８ gas, Si ４ H １０ contains at least one of the gases, The halogen-containing gas is Cl ２ gas, HBr gas, ClF ３ gas, and contains at least one of them The substrate processing method according to any one of Claims 1 to 3.

5. The step of forming the metal film and forming the metal silicide film comprises: A step of supplying a metal-containing gas and a reducing gas to generate a plasma, exposing the substrate to the plasma, and forming the metal film. The substrate processing method according to any one of claims 1 to 4.

6. The metal-containing gas contains at least one of TiCl ４ gas and TiBr ４ gas. The reducing gas contains at least one of H ２ gases. The substrate processing method according to claim 5.

7. The insulating film is SiN or SiO ２ and The epitaxial layer contains Si or SiGe. The substrate processing method according to any one of claims 1 to 6.

8. Before the step of selectively forming the silicon film, A step of removing an oxide film formed on the surface of the epitaxial layer exposed from the through hole is included. The substrate processing method according to any one of claims 1 to 7.

9. The steps of removing the oxide film, selectively forming the silicon film, forming the metal film, and forming the metal silicide film are performed without breaking the vacuum. The substrate processing method according to claim 8.

10. A first processing apparatus for removing an oxide film formed on the surface of the epitaxial layer exposed from the through hole with respect to a substrate having a base portion having an epitaxial layer formed by epitaxial growth and an insulating film having a through hole formed on the base portion and exposing the epitaxial layer. A second processing apparatus for selectively forming a silicon film on the surface of the epitaxial layer exposed from the through hole rather than on the side wall of the through hole. A third processing apparatus for forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than on the side wall of the through hole, and reacting the silicon film and the metal film to form a metal silicide film. The second processing apparatus is configured to be able to execute a step of supplying a silicon-containing gas to form a silicon film and a step of supplying a halogen-containing gas to remove the silicon film formed on the side wall of the through hole. In the step of forming the silicon film, the silicon film formed at the bottom of the through hole is crystalline silicon, and the silicon film formed on the side wall of the through hole is amorphous silicon. In the step of removing the silicon film, the amorphous silicon formed on the side wall of the through hole is selectively removed. Substrate processing system.

11. ​ A substrate having a base portion with an epitaxial layer formed by epitaxial growth and an insulating film formed on the base portion and having a through-hole exposing the epitaxial layer, and a first processing apparatus for removing an oxide film formed on the surface of the epitaxial layer exposed from the through-hole, a second processing apparatus for selectively forming a silicon film on the surface of the epitaxial layer exposed from the through-hole rather than on the side wall of the through-hole, and a third processing apparatus for forming a metal film on the silicon film formed on the surface of the epitaxial layer rather than on the side wall of the through-hole and reacting the silicon film with the metal film to form a metal silicide film, wherein the second processing apparatus removes amorphous silicon formed on the side wall of the through-hole by simultaneously supplying a silicon-containing gas and a halogen-containing gas, and crystalline silicon is selectively formed at the bottom of the through-hole, a substrate processing system.

Images