JP2011216848A - Method of manufacturing semiconductor device, and manufacturing method and processing apparatus for substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a semiconductor and a processing apparatus for a substrate that uniformly film a plurality of substrates in silicon carbide epitaxial film growth carried out under a high-temperature condition.SOLUTION: The method of manufacturing a semiconductor device in a semiconductor manufacturing apparatus includes a first gas supply nozzle and a second gas supply nozzle provided to be extended in a longitudinal direction, wherein the first gas supply nozzle is provided with a first gas supply port and the second gas supply nozzle is provided with a second gas supply port, and the second gas supply nozzle is installed between the substrate and first gas supply nozzle. The method of manufacturing the semiconductor device includes the processes of: installing the plurality of substrates, stacked and arrayed in a longitudinal direction, into a reaction chamber; supplying a silicon-atom-containing gas and a chlorine-atom-containing gas through the first gas supply port and supplying a carbon-atom-containing gas and a reduction gas through the second gas supply port to form silicon carbide films on substrate surfaces; and taking out the plurality of substrates from the reaction chamber.

Description

  The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus including a step of processing a substrate such as a wafer, and more particularly, to a method of manufacturing a semiconductor device including a step of forming a silicon carbide (SiC) epitaxial film on a substrate. And a substrate manufacturing method and a substrate processing apparatus.

Silicon carbide is attracting attention as an element material for power devices. On the other hand, it is known that silicon carbide is more difficult to produce a crystal substrate and a device than silicon (Si).
In a conventional semiconductor manufacturing apparatus for forming a silicon carbide epitaxial film, a plurality of substrates are arranged in a plane on a plate-shaped susceptor, heated to 1500 ° C. to 1800 ° C., and a source gas used for film formation from one place. A silicon carbide epitaxial film was grown on the substrate by supplying the reaction chamber.

  In Patent Document 1, the substrate of the susceptor is held in order to suppress the deposition of deposits caused by the source gas on the surface facing the susceptor and the destabilization of silicon carbide epitaxial growth due to the generation of source gas convection. A vacuum film forming apparatus and a thin film forming method which are arranged so that the surface faces downward are disclosed.

JP 2006-196807 A

However, there are some problems in the prior art. First, when processing a large number of substrates, or when using a large-diameter substrate, it is necessary to increase the susceptor, which increases the floor area of the reaction chamber, and the source gas is supplied from a single location. Therefore, the gas concentration distribution in the reaction chamber is not uniform, the thickness of the film formed on the wafer is non-uniform, and when the SiC epitaxial film is grown, the temperature is 1500 ° C. to 1800 ° C. Since the process is performed at a high temperature, it is difficult to control the temperature in the wafer surface.
The present invention solves the above-described problems, and a semiconductor device manufacturing method, a substrate manufacturing method, and a substrate processing apparatus capable of uniformly forming a plurality of substrates in silicon carbide epitaxial film growth performed under high temperature conditions The purpose is to provide.

A typical configuration of a method of manufacturing a semiconductor device according to the present invention for solving the above-described problems is as follows.
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at one or more positions different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a semiconductor device in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
Carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. Forming, and
Unloading the substrate from the reaction chamber;
A method for manufacturing a semiconductor device comprising:

A typical configuration of the substrate processing apparatus according to the present invention is as follows.
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply system for supplying at least a silicon-containing gas and a chlorine-containing gas into the reaction chamber;
A second gas supply system for supplying at least a carbon-containing gas and a reducing gas into the reaction chamber;
A first gas supply nozzle provided to extend to the array region of the substrate in the reaction chamber;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at a position different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
The first gas supply system supplies at least a silicon-containing gas and a chlorine-containing gas from the first gas supply port into the reaction chamber, and the second gas supply system supplies the second gas supply. A controller for controlling at least a carbon-containing gas and a reducing gas to be formed from the mouth into the reaction chamber so that a silicon carbide film is formed on the substrate;
With
The substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle.

Moreover, the typical structure of the manufacturing method of the board | substrate which concerns on this invention is as follows.
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at one or more positions different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a substrate in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
Carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. Forming, and
Unloading the substrate from the reaction chamber;
A method for manufacturing a substrate comprising:

  According to the semiconductor device manufacturing method, the substrate manufacturing method, and the substrate processing apparatus, the silicon-containing gas supplied from the first gas supply port and the second gas supply port in the reaction chamber as compared with the conventional method. Since the supplied carbon-containing gas can be mixed before reaching the substrate, the Si / C distribution in the wafer surface of the silicon carbide film to be formed is better (the Si / C is less unevenly distributed). Semiconductor devices and substrates can be manufactured.

The perspective view of the semiconductor manufacturing apparatus 10 in each embodiment of this invention is shown. The vertical sectional view which looked at the semiconductor manufacturing apparatus 10 in each embodiment of this invention from the side is shown. 1 is a horizontal sectional view of a semiconductor manufacturing apparatus 10 according to a first embodiment of the present invention as viewed from above. The structure of the control part of the semiconductor manufacturing apparatus 10 in each embodiment of this invention is shown. The equilibrium state in each temperature in the gas supply conditions of a reference example is shown. The equilibrium state in each temperature in the gas supply conditions of each embodiment of this invention is shown. 1 schematically illustrates a processing furnace 40 and its peripheral structure of a semiconductor manufacturing apparatus 10 according to each embodiment of the present invention. The horizontal cross section (a) which looked at the semiconductor manufacturing apparatus 10 in 1st Embodiment of this invention from the upper surface, AA 'cross section (c) in the shape (b) and (b) of a supply nozzle are shown. The result of having calculated the mixing degree of silicon containing gas and carbon containing gas at the time of using the double opposing nozzle of 1st Embodiment of this invention is shown. The horizontal sectional view which looked at the semiconductor manufacturing apparatus 10 in 1st Embodiment of this invention from the upper surface is shown. An example of the C / Si ratio and film formation rate on the monitor line in FIG. The example of C / Si ratio of 1st Embodiment and the modification A on the monitor line of Fig.10 (a) is shown. The horizontal sectional view which looked at the semiconductor manufacturing apparatus 10 in 2nd Embodiment of this invention from the upper surface is shown. The horizontal sectional view which looked at the semiconductor manufacturing apparatus 10 in 3rd Embodiment of this invention from the upper surface is shown.

[First embodiment]
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an example of a semiconductor manufacturing apparatus 10 as a substrate processing apparatus for forming a silicon carbide epitaxial film in each of the first to third embodiments of the present invention. This semiconductor manufacturing apparatus 10 is a batch type vertical heat treatment apparatus, and has a casing 12 in which a main part is arranged. In the semiconductor manufacturing apparatus 10, for example, a hoop (hereinafter referred to as a pod) 16 is used as a wafer carrier as a substrate container for storing a wafer 14 as a substrate made of silicon (Si) or silicon carbide (SiC). The A pod stage 18 is disposed on the front side of the housing 12, and the pod 16 is transported to the pod stage 18 from the outside of the apparatus 10. For example, 25 wafers 14 are stored in the pod 16 and set on the pod stage 18 with the lid closed.

  A pod transfer device 20 is arranged on the front side in the housing 12 and at a position facing the pod stage 18. A pod storage shelf 22, a pod opener 24, and a substrate number detector 26 are disposed in the vicinity of the pod transfer device 20. The pod storage shelf 22 is arranged above the pod opener 24 and is configured to hold a plurality of pods 16 mounted thereon. The substrate number detector 26 is disposed adjacent to the pod opener 24. The pod transfer device 20 transfers the pod 16 among the pod stage 18, the pod storage shelf 22, and the pod opener 24. The pod opener 24 opens the lid of the pod 16, and the substrate number detector 26 detects the number of wafers 14 in the pod 16 with the lid opened.

  A substrate transfer device 28 and a boat 30 as a substrate support are disposed in the housing 12. The substrate transfer machine 28 has an arm (tweezer) 32 and has a structure that can be rotated up and down by a driving means (not shown). For example, the arm 32 can take out five wafers, and by moving the arm 32, the wafer 14 is transferred between the pod 16 and the boat 30 placed at the position of the pod opener 24.

The boat 30 is made of a heat-resistant material such as carbon graphite or silicon carbide (SiC), for example, and a plurality of wafers 14 are aligned in a horizontal posture and aligned with each other, and stacked and held in the vertical direction. Is configured to do. A boat heat insulating portion 34 as a cylindrical heat insulating member made of a heat resistant material such as quartz or silicon carbide (SiC) is disposed at the lower portion of the boat 30. The heat is not easily transmitted to the lower side of the processing furnace 40 (see FIG. 2).
A processing furnace 40 is disposed in the upper part on the back side in the housing 12. The boat 30 loaded with a plurality of wafers 14 is loaded into the processing furnace 40 and subjected to heat treatment.

  FIG. 2 shows a side cross-sectional view of the processing furnace 40 of the semiconductor manufacturing apparatus 10 for forming a silicon carbide epitaxial film in each of the first to third embodiments. FIG. 3 is a horizontal sectional view of the semiconductor manufacturing apparatus 10 according to the first embodiment of the present invention as viewed from above. 2 and 3, a first gas supply nozzle 60 having a first gas supply port 68, a second gas supply nozzle 70 having a second gas supply port 72, and a first gas exhaust port 90 are provided. It is shown in the figure. The first gas supply port 68 supplies at least a silicon-containing gas and a chlorine-containing gas. The second gas supply port 72 supplies at least a carbon-containing gas and a reducing gas. Further, a third gas supply port 360 and a second gas exhaust port 390 for supplying an inert gas are illustrated between the reaction tube 42 and the heat insulating material 54 forming the reaction chamber.

  The processing furnace 40 includes a reaction tube 42 that forms a cylindrical reaction chamber 44. The reaction tube 42 is made of a heat-resistant material such as quartz or silicon carbide (SiC), and has a cylindrical shape with the upper end closed and the lower end opened. A reaction chamber 44 is formed in a hollow cylindrical portion inside the reaction tube 42. The reaction chamber 44 is a state in which the wafers 14 made of silicon (Si), silicon carbide (SiC), or the like are aligned on the boat 30 in a horizontal posture and aligned with each other, and stacked and held in the vertical direction. It is configured so that it can be stored.

  Below the reaction tube 42, a manifold 91 is disposed concentrically with the reaction tube 42. The manifold 91 is made of, for example, stainless steel and is formed in a cylindrical shape with an upper end and a lower end opened. The manifold 91 is provided so as to support the reaction tube 42. An O-ring (not shown) is provided between the manifold 91 and the reaction tube 42 as a seal member. The manifold 91 is supported by a holding body (not shown), so that the reaction tube 42 is installed vertically. A reaction vessel is formed by the reaction tube 42 and the manifold 91.

The processing furnace 40 includes a heated body 48 to be heated and an induction coil 50 as a magnetic field generation unit. The heated body 48 is disposed in the reaction chamber 44. The heated body 48 is heated by a magnetic field generated by an induction coil 50 provided outside the reaction tube 42. The induction coil 50 is provided so as to wind around the reaction tube 42. As the heated body 48 generates heat, the reaction chamber 44 is heated. The heated object 48 is easily cylindrically heated by an induction current generated by the induction coil 50 and is made of a material having excellent heat resistance, such as carbon graphite, with a closed upper end and an open lower end. Is formed.
In the vicinity of the object to be heated 48, a temperature sensor (not shown) is provided as a temperature detector for detecting the temperature in the reaction chamber 44. A temperature control unit 52 is electrically connected to the induction coil 50 and the temperature sensor, and the amount of current supplied to the induction coil 50 is adjusted based on the temperature information detected by the temperature sensor. The temperature is controlled to have a predetermined temperature distribution at a predetermined timing (see FIG. 4).
Inside the heated body 48, a first gas supply nozzle 60, a second gas supply nozzle 70, and a first gas exhaust port 90 are provided to form a reaction space to which a reaction gas is supplied.

  Preferably, in the reaction chamber 44, between the first gas supply nozzle 60 and the second gas supply nozzle 70 and the first gas exhaust port 90, and between the heated object 48 and the wafer 14. The structure 400 is preferably provided. By providing the structure 400, the flow velocity and flow rate of the reaction gas flowing in the region (substrate array region) in which the wafers 14 serving as substrates are stacked in the vertical direction are made uniform. For example, as shown in FIG. 3, the structures 400 are provided at the opposing positions. As shown in FIG. 3, the structure 400 is a pillar having a horizontal cross section that has an arcuate shape, that is, a shape in which an inner periphery and an outer periphery draw an arc, and at least the wafer 14 loaded in the vertical direction exists. It is provided so as to correspond to the region (substrate array region). The structure 400 is preferably made of a heat insulating material, carbon felt, or the like, has heat resistance and can suppress generation of particles.

A heat insulating material 54 is provided between the heated object 48 and the reaction tube 42, and by providing this heat insulating material 54, the heat of the heated object 48 is transmitted to the reaction tube 42 or the outside of the reaction tube 42. Can be suppressed. The heat insulating material 54 is made of, for example, a carbon felt that is not easily induced, and is formed in a cylindrical shape with an upper end and a lower end opened.
In addition, an outer heat insulating wall 92 having, for example, a water cooling structure is provided outside the induction coil 50 so as to prevent the heat in the reaction chamber 44 from being transmitted to the outside so as to surround the reaction chamber 44. . The outer heat insulating wall 92 is made of a material that is difficult to be induction-heated by the induction current generated from the induction coil 50, for example, a material such as copper (Cu), and is formed in a cylindrical shape having an open upper end and a lower end. Further, a magnetic shield 58 for preventing the magnetic field generated by the induction coil 50 from leaking outside is provided outside the outer heat insulating wall 92. Preferably, the magnetic shield 58 is made of a material that is difficult to be induction-heated by an induction current generated from the induction coil, for example, a material such as copper (Cu) or aluminum (Al), and has a closed upper end and an open lower end. It is formed into a shape.

  As shown in FIG. 2, at least one first gas supply port 68 provided in the first gas supply nozzle 60 and at least one second gas supply nozzle 70 are provided between the heating body 48 and the wafer 14. One second gas supply port 72 and a first gas exhaust port 90 are provided. The first gas supply port 68 supplies at least a silicon-containing gas and a chlorine-containing gas. The second gas supply port 72 supplies at least a carbon-containing gas and a reducing gas. Further, a third gas supply port 360 and a second gas exhaust port 390 are arranged between the reaction tube 42 and the heat insulating material 54. Each will be described in detail.

The first gas supply nozzle 60 is provided in the reaction chamber 44. The first gas supply nozzle 60 is made of, for example, carbon graphite, and is attached to the manifold 91 so as to penetrate the manifold 91. A plurality of first gas supply nozzles 60 may be provided. At least one first gas supply port 68 provided in the first gas supply nozzle 60 has, for example, silane (SiH ₄ ) gas as a silicon-containing gas, and hydrogen chloride (HCl) gas as a chlorine-containing gas, and the reaction chamber 44. Supply in.

The first gas supply nozzle 60 is connected to a first gas line (gas supply pipe) 222. In this example, the first gas line 222 is connected to a silane (SiH ₄ ) gas source 210a via a mass flow controller (hereinafter referred to as MFC) 211a as a flow rate controller (flow rate control means) and a valve 212a. It is connected. The first gas line 222 is connected to a hydrogen chloride (HCl) gas source 210b via an MFC 211b and a valve 212b.
With this configuration, the supply flow rate, concentration, and partial pressure of the silane (SiH ₄ ) gas and hydrogen chloride (HCl) gas supplied into the reaction chamber 44 can be controlled. The valves 212a and 212b and the MFCs 211a and 211b are electrically connected to the gas flow rate control unit 78, and are controlled so that the flow rate of the supplied gas becomes a predetermined flow rate at a predetermined timing (see FIG. 4). . In this example, a silane (SiH ₄ ) gas source 210a, a hydrogen chloride (HCl) gas source 210b, valves 212a and 212b, MFCs 211a and 211b, a first gas line 222, a first gas supply nozzle 60, and a first gas. The supply port 68 constitutes a first gas supply system.

In the above example, silane (SiH ₄ ) gas is exemplified as the silicon-containing gas. However, the present invention is not limited to this, and disilane (Si ₂ H ₆ ) gas, trisilane (Si ₃ H ₈ ) gas, or the like may be used. These gases may be used in combination.
In the above example, hydrogen chloride (HCl) gas is exemplified as the chlorine-containing gas. However, the present invention is not limited to this, and chlorine gas may be used, or these gases may be used in combination. Yes.
In the above-described example, the silicon-containing gas and the chlorine-containing gas are supplied. However, a gas containing silicon and chlorine, for example, tetrachlorosilane (SiCl ₄ ) gas, trichlorosilane (SiHCl ₃ ) gas, dichlorosilane (SiH) ₂ Cl ₂ ) gas may be supplied.

A second gas supply nozzle 70 that supplies at least a carbon-containing gas and a reducing gas is provided in the reaction chamber 44. The second gas supply nozzle 70 is made of carbon graphite, for example, and is attached to the manifold 91 so as to penetrate the manifold 91. A plurality of second gas supply nozzles 70 may be provided. The second gas supply port 72 provided in the second gas supply nozzle 70 has, for example, propane (C ₃ H ₈ ) gas as the carbon-containing gas and hydrogen (H ₂ ) gas as the reducing gas in the reaction chamber 44. Supply.

The second gas supply nozzle 70 is connected to a second gas line (gas supply pipe) 260. In this example, the second gas line 260 is connected to the propane (C ₃ H ₈ ) gas source 210c via the MFC 211c and the valve 212c, and is also connected to the hydrogen (H ₂ ) gas source via the MFC 211d and the valve 212d. 210d.
With this configuration, the supply flow rate, concentration, and partial pressure of propane (C ₃ H ₈ ) gas and hydrogen (H ₂ ) gas supplied into the reaction chamber 44 can be controlled. The valves 212c and 212d and the MFCs 211c and 211d are electrically connected to the gas flow rate control unit 78, and are controlled so that the flow rate of the supplied gas becomes a predetermined flow rate at a predetermined timing (see FIG. 4). In this example, a propane (C ₃ H ₈ ) gas source 210c, a hydrogen (H ₂ ) gas source 210d, valves 212c and 212d, MFCs 211c and 211d, a second gas line 260, a second gas supply nozzle 70, a second The gas supply port 72 constitutes a second gas supply system.

Although exemplified propane _(C 3 _{H 8)} gas as a carbon-containing gas is not limited thereto, ethylene _(C 2 _{H 4)} gas, acetylene _(C 2 _{H 2)} may be used gas or the like, and, These gases may be used in combination.
The first gas supply port 68 and the second gas supply port 72 are each a plurality of wafers that are stacked and held in the vertical direction while being aligned with the boat 30 in a horizontal posture and aligned with each other. 14 is preferably provided so as to supply gas for each wafer 14. This makes it easy to control the in-plane uniformity of the film thickness of each wafer 14.
However, the present invention is not limited to this, and at least one of the first gas supply port 68 and the second gas supply port 72 is provided in the array region of the wafers 14 stacked in the vertical direction (substrate array region). May be.
In the above-described embodiment, the silicon-containing gas, the chlorine-containing gas, and the carbon-containing gas and the reducing gas are supplied from the first gas supply nozzle 60 and the second gas supply nozzle 70. However, the present invention is not limited to this. A gas supply nozzle may be provided for each species.

Here, the reason why the first gas supply system and the second gas supply system are configured will be described in detail. In a conventional semiconductor manufacturing apparatus for forming a silicon carbide epitaxial film, a plurality of wafers 14 are arranged so as not to overlap each other on a susceptor, and a source gas composed of a silicon-containing gas, a carbon-containing gas, a reducing gas, etc. The silicon carbide epitaxial film was formed from one location of 44.
In the present invention, a plurality of wafers 14 made of silicon carbide (SiC) or the like are aligned and held in a horizontal posture with their centers aligned, and are stacked and held in the vertical direction. The gas is supplied from an extended gas supply nozzle. At this time, since the source gas is consumed in the gas supply nozzle, a source gas shortage occurs on the downstream side of the gas supply nozzle, and deposits such as a silicon carbide (SiC) film deposited by reaction in the gas supply nozzle However, problems such as blocking the gas supply nozzle, or unstable supply of raw material gas and generation of particles are likely to occur.

The inventor of the present invention performed calculations as shown in FIGS. 5 and 6 in order to solve these points. FIG. 5 is a reference example for comparison with the present invention. Tetrachlorosilane (SiCl ₄ ) gas as a gas containing silicon and chlorine, propane (C ₃ H ₈ ) gas as a carbon-containing gas, and the function of a carrier gas 2 shows the chemical equilibrium state at each temperature when argon (Ar) gas is supplied as a rare gas in a ratio of tetrachlorosilane gas: propane gas: argon gas = 8: 4: 571. At this time, the flow rate of each gas type is 8.0 sccm for tetrachlorosilane (SiCl ₄ ) gas, 4.0 sccm for propane (C ₃ H ₈ ) gas, and 571 sccm for argon (Ar) gas, and the pressure at this time is 100 Torr. It is said. This is to simulate the state in the gas supply nozzle when tetrachlorosilane (SiCl ₄ ) gas, propane (C ₃ H ₈ ) gas, and argon (Ar) gas are supplied using one gas supply nozzle. Yes. The chemical equilibrium state refers to the state of each gas that reaches when the molar fraction of the gas is given as an initial condition and maintained at that temperature for an infinite time. The horizontal axis indicates the temperature in the equilibrium state, and the vertical axis indicates the supplied raw material gas and the mole fraction generated by the decomposition or combination of the supplied raw material gases. Further, argon (Ar) gas is excluded from FIG.

In FIG. 5, a large amount of hydrogen chloride (HCl) gas, dichlorochlorosilane (SiCl ₂ ) gas, acetylene (C ₂ H ₂ ) gas, and hydrogen (H ₂ ) gas exists at least in the temperature range of 1000 ° C. to 1600 ° C. is doing. That is, in the above-described temperature range where silicon carbide (SiC) epitaxial growth is performed, one gas supply nozzle is installed in the reaction chamber 44, and tetrachlorosilane (SiCl ₄ ) gas, propane (C ₃ H ₈ ) gas, argon When the (Ar) gas is supplied, the hydrogen chloride (HCl) gas, dichlorochlorosilane (SiCl ₂ ), acetylene (C ₂ H ₂ ) gas, and hydrogen (H ₂ ) gas are generated in the gas supply nozzle. become. For example, when the equilibrium temperature is 1400 ° C., many gases are generated in the order of hydrogen chloride (HCl) gas, dichlorochlorosilane (SiCl ₂ ) gas, acetylene (C ₂ H ₂ ) gas, and hydrogen (H ₂ ) gas. Then, a dichlorochlorosilane (SiCl ₂ ) gas and an acetylene (C ₂ H ₂ ) gas react to form a silicon carbide (SiC) polycrystalline (SiC-Poly) film in the gas supply nozzle. is expected.

  At this time, hydrogen chloride (HCl) gas having an etching action also exists, but since the hydrogen chloride (HCl) gas has a small etching effect on silicon carbide (SiC) at 1500 ° C. or less, the polycrystalline film of silicon carbide (SiC) is The gas supply nozzle is clogged, and particles are generated when the deposited polycrystalline film of silicon carbide (SiC) is peeled off.

As a solution to this problem, the inventors of the present invention performed the calculation shown in FIG. FIG. 6 shows an equilibrium state at each temperature under the gas supply conditions of the embodiment of the present invention, and is a calculation result when the carbon-containing gas is removed from the conditions of FIG. At each temperature when tetrachlorosilane (SiCl ₄ ) gas as a gas containing silicon and chlorine, argon (Ar) gas as a rare gas as a carrier gas, and tetrachlorosilane gas: argon gas = 8: 571 are supplied. The equilibrium state is shown. At this time, the flow rate of each gas type is 8.0 sccm for tetrachlorosilane (SiCl ₄ ) gas and 570 sccm for argon (Ar) gas, and the pressure at this time is 100 Torr. This simulates the state in the gas supply nozzle when tetrachlorosilane (SiCl ₄ ) gas and argon (Ar) gas are supplied using the first gas supply nozzle in the present invention. Further, argon (Ar) gas is excluded from FIG.

As shown in FIG. 6, the tetrachlorosilane (SiCl ₄ ) gas hardly decomposes to around 1200 ° C. This is probably because the reduction reaction of tetrachlorosilane (SiCl ₄ ) gas by hydrogen contained in the propane (C ₃ H ₈ ) gas occurs in the case of FIG. 5, whereas in FIG. Since there is no C ₃ H ₈ ) gas, it is considered that the tetrachlorosilane (SiCl ₄ ) gas hardly decomposes to around 1200 ° C. Further, it is known that tetrachlorosilane (SiCl ₄ ) gas alone does not contribute to the formation of a silicon carbide film, and at least up to about 1200 ° C., a silicon carbide polycrystalline film or the like is placed in the gas supply nozzle. It is considered that deposits are not easily generated.

On the other hand, when the temperature is 1200 ° C. or higher, tetrachlorosilane (SiCl ₄ ) gas is decomposed to generate dichlorosilane (SiCl ₂ ) gas and chlorine (Cl) gas. A polycrystalline film of, for example, silicon carbide is expected to be formed by dichlorosilane (SiCl ₂ ) gas. In this case, since chlorine (Cl) gas having an etching effect is generated at the same time, the film in the gas supply nozzle is generated. It is believed that no deposition occurs. Further, since there is no hydrogen in the nozzle, a film formation reaction such as SiCl ₂ + H ₂ → Si (Solid) + 2HCl does not occur, so it is considered that the film is difficult to adhere inside the nozzle.

  That is, at least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply nozzle 60, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply nozzle 70. It is possible to suppress the consumption of the supply gas in the interior, suppress the blockage in the gas supply nozzle, and prevent the generation of particles.

Preferably, silicon-containing gas, chlorine-containing gas, and rare gas such as argon (Ar) gas is supplied as carrier gas from the first gas supply nozzle 60, and carbon-containing gas is supplied from the second gas supply nozzle 70. For example, hydrogen (H ₂ ) gas as a reducing gas may be supplied.

More preferably, for example, tetrachlorosilane (SiCl ₄ ) gas as a gas containing silicon and chlorine and a rare gas such as argon (Ar) gas as a carrier gas are supplied from the first gas supply nozzle 60. A carbon-containing gas and, for example, hydrogen (H ₂ ) gas as a reducing gas may be supplied from the second gas supply nozzle 70.
Note that a dopant gas further containing impurities may be supplied into the reaction chamber 44 from the first supply port 68 or the second gas supply port 72. However, the present invention is not limited thereto, and a gas supply nozzle may be further provided to supply the dopant gas, and the dopant gas may be supplied into the reaction chamber 44.

  In addition, as shown in FIG. 3, the first gas exhaust port 90 has a gas supply nozzle 60 connected to the first gas supply port 68 and a gas supply nozzle 70 connected to the second gas supply port 72. A gas exhaust pipe 230 connected to the first gas exhaust port 90 is provided in the manifold 91 so as to pass through the manifold 91. A vacuum exhaust device 220 such as a vacuum pump is connected to the downstream side of the gas exhaust pipe 230 via a pressure sensor 93 as a pressure detector and an APC (Auto Pressure Controller, hereinafter referred to as APC) valve 214 as a pressure regulator. Yes. A pressure control unit 98 is electrically connected to the pressure sensor 93 and the APC valve 214, and the pressure control unit 98 adjusts the opening degree of the APC valve 214 based on the pressure detected by the pressure sensor 93. Thus, the pressure in the processing furnace 40 is controlled to be a predetermined pressure at a predetermined timing (see FIG. 4).

  As described above, at least the silicon-containing gas and the chlorine-containing gas are supplied from the first gas supply port 68, and at least the carbon-containing gas and the reducing gas are supplied from the second gas supply port 72. Since it flows parallel to the surface of the wafer 14 made of silicon or silicon carbide and flows toward the first exhaust port 90, the entire wafer 14 is efficiently and uniformly exposed to the gas.

  As shown in FIG. 3, the third gas supply port 360 is disposed between the reaction tube 42 and the heat insulating material 54 and is attached so as to penetrate the manifold 91. Further, the second gas exhaust port 390 is disposed between the reaction tube 42 and the heat insulating material 54 and is disposed so as to be opposed to the third gas supply port 360. A gas exhaust pipe 230 connected to the second gas exhaust port 390 is provided so as to penetrate therethrough. For example, a rare gas argon (hereinafter referred to as Ar) gas is supplied to the third gas supply port 360 as an inert gas. This prevents, for example, a silicon-containing gas, a carbon-containing gas, a chlorine-containing gas, or a mixed gas thereof from entering the gap between the reaction tube 42 and the heat insulating material 54 as a gas that contributes to the growth of the silicon carbide epitaxial film. It is possible to prevent the inner wall of the pipe 42 or the outer wall of the heat insulating material 54 from deteriorating and unnecessary products from adhering.

  The inert gas supplied between the reaction tube 42 and the heat insulating material 54 is connected to the downstream side of the gas exhaust pipe 230 from the second gas exhaust port 390 as a pressure sensor 93 and an APC as a pressure regulator. The air is exhausted from a vacuum exhaust device 220 such as a vacuum pump through a valve 214. A pressure control unit is electrically connected to the pressure sensor 93 and the APC valve 214, and the pressure control unit adjusts the opening degree of the APC valve 214 based on the pressure detected by the pressure sensor 93. Control is performed at a predetermined timing so that the pressure in the reaction chamber 44 becomes a predetermined pressure (see FIG. 4).

Although exemplified hydrogen (H ₂₎ gas as a reducing gas is not limited thereto, a gas containing hydrogen, then one of the rare gas exhibiting be supplied to at least one of a rare gas and combined gas good. Here, as the rare gas, a rare gas such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, krypton (Kr) gas, or xenon (Xe) gas can be used.

Next, the configuration around the processing furnace 40 will be described.
FIG. 7 shows a schematic diagram of the processing furnace 40 and its peripheral structure. Below the processing furnace 40, a seal cap 102 is provided as a furnace port lid for secretly closing the lower end opening of the processing furnace 40. The seal cap 102 is made of, for example, a metal such as stainless steel and has a disk shape. On the upper surface of the seal cap 102, an O-ring is provided as a seal material that comes into contact with the lower end of the processing furnace 40. A rotation mechanism 218 is provided on the seal cap 102. The rotation shaft 106 of the rotation mechanism 218 is connected to the boat 30 through the seal cap 102, and is configured to rotate the wafer 14 by rotating the boat 30. The seal cap 102 is configured to be moved up and down in the vertical direction by an elevating motor 122, which will be described later, as an elevating mechanism directed to the outside of the processing furnace 40, whereby the boat 30 is carried into and out of the processing furnace 40. It is possible to do. A drive control unit 108 is electrically connected to the rotation mechanism 218 and the lifting motor 122, and is configured to control to perform a predetermined operation at a predetermined timing (see FIG. 4).

  A lower substrate 112 is provided on the outer surface of the load lock chamber 110 as a spare chamber. The lower substrate 112 is provided with a guide shaft 116 that is fitted to the lifting platform 114 and a ball screw 118 that is screwed to the lifting platform 114. The upper substrate 120 is provided on the upper ends of the guide shaft 116 and the ball screw 118 erected on the lower substrate 112. The ball screw 118 is rotated by an elevating motor 122 provided on the upper substrate 120. When the ball screw 118 rotates, the lifting platform 114 is configured to move up and down.

  A hollow elevating shaft 124 is suspended from the elevating table 114, and the connection between the elevating table 114 and the elevating shaft 124 is airtight. The elevating shaft 124 moves up and down together with the elevating table 114. The lifting shaft 124 passes through the top plate 126 of the load lock chamber 110. The through hole of the top plate 126 through which the elevating shaft 124 passes has a sufficient margin so as not to contact the elevating shaft 124. Between the load lock chamber 110 and the lifting platform 114, a bellows 128 is provided as a hollow elastic body having elasticity so as to cover the periphery of the lifting shaft 124 in order to keep the load lock chamber 110 airtight. The bellows 128 has a sufficient expansion / contraction amount that can correspond to the amount of elevation of the lifting platform 114, and the inner diameter of the bellows 128 is sufficiently larger than the outer shape of the lifting shaft 124 so that it does not come into contact with the expansion / contraction of the bellows 128. It is configured.

  An elevating board 130 is fixed horizontally to the lower end of the elevating shaft 124. A drive unit cover 132 is airtightly attached to the lower surface of the elevating substrate 130 via a seal member such as an O-ring. The elevating board 130 and the drive unit cover 132 constitute a drive unit storage case 134. With this configuration, the inside of the drive unit storage case 134 is isolated from the atmosphere in the load lock chamber 110.

  Further, a rotation mechanism 218 of the boat 30 is provided inside the drive unit storage case 134, and the periphery of the rotation mechanism 218 is cooled by the cooling mechanism 136.

  The power cable 138 passes from the upper end of the elevating shaft 124 through the hollow portion of the elevating shaft 124 and is guided and connected to the rotating mechanism 218. A cooling water flow path 140 is formed in the cooling mechanism 136 and the seal cap 102. The cooling water pipe 142 passes from the upper end of the elevating shaft 124 through the hollow portion of the elevating shaft 124 and is guided and connected to the cooling flow path 140.

When the elevating motor 122 is driven and the ball screw 118 rotates, the drive unit storage case 134 is raised and lowered via the elevating table 114 and the elevating shaft 124.
As the drive unit storage case 134 is raised, the seal cap 102 provided in an airtight manner on the elevating substrate 130 closes the furnace port 144 that is an opening of the processing furnace 40, so that wafer processing is possible. When the drive unit storage case 134 is lowered, the boat 30 is lowered together with the seal cap 102, and the wafer 14 can be carried out to the outside.

  FIG. 4 shows a control configuration of each part constituting semiconductor manufacturing apparatus 10 for forming a silicon carbide epitaxial film. The temperature control unit 52, the gas flow rate control unit 78, the pressure control unit 98, and the drive control unit 108 are electrically connected to a main control unit 150 that controls the entire semiconductor manufacturing apparatus 10. The main control unit 150 includes an operation unit and an input / output unit (not shown). These temperature control unit 52, gas flow rate control unit 78, pressure control unit 98, and drive control unit 108 are configured as a controller 152.

  Next, using the heat treatment apparatus 10 configured as described above, for example, a silicon carbide film is formed on a substrate such as a wafer 14 made of silicon carbide (SiC) or the like as one step of a semiconductor device manufacturing process. How to do will be described. In the following description, the operation of each part constituting the heat treatment apparatus 10 is controlled by the controller 152.

  First, when the pod 16 containing a plurality of wafers 14 is set on the pod stage 18, the pod 16 is transferred from the pod stage 18 to the pod storage shelf 22 by the pod transfer device 20, and the pod 16 is stored in the pod storage shelf 22. To do. Next, the pod 16 stocked on the pod storage shelf 22 is transported and set to the pod opener 24 by the pod transport device 20, the lid of the pod 16 is opened by the pod opener 24, and the pod 16 is detected by the substrate number detector 26. The number of wafers 14 accommodated in is detected.

Next, the wafer 14 is taken out from the pod 16 at the position of the pod opener 24 by the substrate transfer device 28 and transferred to the boat 30.
When a plurality of wafers 14 are loaded on the boat 30, the boat 30 holding the plurality of wafers 14 is loaded into the reaction chamber 44 by the lifting / lowering operation of the lifting / lowering table 114 and the lifting / lowering shaft 124 by the lifting / lowering motor 122 (boat loading). ) In this state, the seal cap 102 seals the lower end of the manifold 91 via the O-ring.

  The reaction chamber 44 is evacuated by the evacuation device 220 so that the pressure in the reaction chamber 44 becomes a predetermined pressure (degree of vacuum). At this time, the pressure in the reaction chamber 44 is measured by the pressure sensor 93, and the APC valve 214 communicating with the first gas exhaust port 90 and the second gas exhaust port 390 is feedback-controlled based on the measured pressure. The Further, the object to be heated 48 is heated so that the inside of the wafer 14 and the reaction chamber 44 has a predetermined temperature. At this time, the energization amount to the induction coil 50 is feedback-controlled based on the temperature information detected by the temperature sensor so that the reaction chamber 44 has a predetermined temperature distribution. Subsequently, the wafer 30 is rotated in the circumferential direction by rotating the boat 30 by the rotation mechanism 218.

Subsequently, the silicon-containing gas and the chlorine-containing gas contributing to the silicon carbide epitaxial growth reaction are respectively supplied from the gas sources 210a and 210b, and are ejected from the gas supply port 68 into the reaction chamber 44, and the carbon-containing gas and the reducing gas are also supplied. The hydrogen (H ₂ ) gas is supplied from the gas sources 210c and 210d, and is ejected into the reaction chamber 44 from the gas supply port 72 to undergo a silicon carbide epitaxial growth reaction.

At this time, the openings of the corresponding MFCs 211a and 211b are adjusted so that the silicon-containing gas and the chlorine-containing gas have predetermined flow rates, and then the valves 212a and 212b are opened, and the respective gases are the first gas. After flowing through the supply pipe 222, it flows through the first gas supply nozzle 60 and is supplied from the first gas supply port 68 into the reaction chamber 44. In addition, the opening of the corresponding MFCs 211c and 211d is adjusted so that the carbon-containing gas and the hydrogen (H ₂ ) gas as the reducing gas have predetermined flow rates, and then the valves 212c and 212d are opened. After the gas flows through the second gas supply pipe 260, the gas flows through the second gas supply nozzle 70 and is introduced into the reaction chamber 44 through the second gas supply port 72.

  The gas supplied from the first gas supply port 68 and the second gas supply port 72 passes through the reaction space inside the heated body 48 in the reaction chamber 44 and is exhausted from the first gas exhaust port 90. Exhaust through tube 230. The gas supplied from the first gas supply port 68 and the second gas supply port 72 comes into contact with the wafer 14 made of SiC or the like when passing through the reaction chamber 44, and on the surface of the wafer 14. A silicon carbide epitaxial film is grown.

  Further, after the opening degree of the corresponding MFC 211e is adjusted by the gas supply source 210e so that argon (Ar) gas, which is a rare gas as an inert gas, has a predetermined flow rate, the valve 212e is opened, Then, the gas is supplied through the third gas supply port 360 into the reaction chamber 44. The argon (Ar) gas supplied from the third gas supply port 360 passes between the heat insulating material 54 in the reaction chamber 44 and the reaction tube 42 and is exhausted from the second gas exhaust port 390.

  When the preset time elapses, the supply of the gas is stopped and the silicon carbide epitaxial film growth is stopped. In addition, an inert gas is supplied into the reaction chamber 44 from an inert gas supply source (not shown), the inside of the reaction chamber 44 is replaced with the inert gas, and the pressure in the reaction chamber 44 is returned to normal pressure.

  Thereafter, the seal cap 102 is lowered by the elevating motor 122 so that the lower end of the manifold 91 is opened, and the processed wafer 14 is carried out from the lower end of the manifold 91 to the outside of the reaction tube 42 while being held in the boat 30 ( The boat 30 waits at a predetermined position until all wafers 14 supported by the boat 30 are cooled. Next, when the wafer 14 of the boat 30 that has been waiting is cooled to a predetermined temperature, the substrate transfer device 28 takes out the wafer 14 from the boat 30 and transfers it to the empty pod 16 set in the pod opener 24. And accommodate. Thereafter, the pod 16 in which the wafers 14 are stored is transferred to the pod storage shelf 22 or the pod stage 18 by the pod transfer device 20. In this way, a series of operations of the semiconductor manufacturing apparatus 10 is completed.

As described above, the growth of the deposited film in the gas supply nozzle is suppressed, and in the reaction chamber 44, the silicon-containing gas, the carbon-containing gas, the chlorine-containing gas, and hydrogen (H ₂ ), which is the reducing gas, are supplied from the gas supply nozzle. In a state where a plurality of wafers 14 composed of silicon carbide (SiC) and the like are aligned in a horizontal posture and aligned in the center and stacked and held vertically by the reaction of the gas. In addition, silicon carbide epitaxial growth can be performed.

FIG. 8 shows an example of the first embodiment. FIG. 8A shows a horizontal cross-sectional view of the semiconductor manufacturing apparatus 10 according to the first embodiment as viewed from above. FIG. 8B is a perspective view showing an example of a gas supply nozzle shape in the first embodiment. FIG. 8C shows a cross-sectional view taken along AA ′ in FIG.
As shown in FIGS. 8A and 8B, a pair (two) of the first gas supply nozzles 60 are provided, and the gas supply ports 68 of the pair of nozzles are disposed so as to face each other. Also, a pair of second gas supply nozzles 70 are provided, and the gas supply ports 72 of the pair of nozzles are disposed so as to face each other. The second gas supply nozzle 70 is disposed in the space between the first gas supply nozzle 60 and the wafer 14.
Thus, in the reaction space between the outer periphery of the wafer 14 and the object to be heated 48, a pair of first gas supply nozzles 60 is provided along the object to be heated 48 that is the side wall of the reaction space. It is preferable to install the gas supply ports 68 of the nozzles so as to face each other. Further, in the space between the outer periphery of the wafer 14 and the first gas supply nozzle 60, a pair of second gas supply nozzles 70 are installed so that the gas supply ports 72 of the pair of nozzles face each other. It is preferable (hereinafter sometimes referred to as a double counter nozzle).

  According to this configuration, the reaction gas is mixed in a space closer to the wafer 14 and can be supplied to the entire wafer 14, whereby a silicon carbide film can be uniformly formed on the wafer 14. Moreover, it is preferable that the supply amount of the reducing gas, for example, hydrogen gas, supplied from the second gas supply port 72 is very large as compared with the silicon-containing gas, the chlorine-containing gas, and the carbon-containing gas. In this way, the reaction gas can be more easily mixed, and the reaction gas can flow more uniformly with respect to the wafer 14, so that the silicon carbide film can be uniformly formed on the wafer 14.

In addition, the first gas supply nozzle 60 has a first direction parallel to the substrate surface in the direction of the gas supply nozzle 60 facing the first gas supply nozzle 60 (the x direction in FIG. 8A). 1) one or more first gas supply ports 68 through which gas flows out are provided, and the second gas supply nozzle 70 has a second gas outflow in a second direction opposite to the first direction. One or more gas supply ports 72 are provided.
More specifically, at least one pair of first electrodes arranged in a direction perpendicular to the radial direction of the substrate (y direction in FIG. 8A) and parallel to the substrate surface (the same x direction) and facing each other. The gas supply nozzle 60 and a position between the first gas supply nozzle 60 and the outer periphery of the substrate are perpendicular to the radial direction of the substrate (the same y direction) and parallel to the substrate surface (the same x direction). And at least one pair of second gas supply nozzles 70 provided to face each other, and at least one of the pair of first gas supply nozzles 60 includes the one nozzle and There are provided one or more first gas supply ports 68 through which gas flows out in the direction of the gas supply nozzles 60 facing each other and in a first direction (the same x direction) parallel to the substrate surface. Of the other gas supply nozzles 60, One or more first gas supply ports 68 through which gas flows out in a second direction opposite to the first direction are provided in the sull, and at least one of the pair of second gas supply nozzles 70 is provided. One nozzle is provided with one or more second gas supply ports 72 through which gas flows out in the first direction, and at least one of the pair of second gas supply nozzles 70 includes the second gas supply port 72. One or more second gas supply ports 72 through which gas flows out in the direction of 2 are provided.

  Further, as shown in FIG. 8C, the gas supply ports 68 of the two nozzles 60 are installed by shifting the positions of the opposing gas supply ports 68 in the vertical direction by a fixed distance a in the wafer mounting region. To do. Similarly, the gas supply ports 72 of the two nozzles 70 are installed by shifting the position of the gas supply ports 72 facing each other in the vertical direction by a certain distance a in the wafer placement region. As a result, the gas exiting from the gas supply ports 68 and 72 facing each other does not collide and mix at one point in the space between the two nozzles, but collides with the wall surfaces of the nozzles facing each other and vortexes to mix. . Since there is no need to mix for a single point in the space, even if the positioning accuracy when creating the gas supply port and the positioning accuracy when assembling the nozzle are low, a uniform gas flow between the wafer surfaces should be realized. Is possible.

With the above configuration, in the region around the gas supply port 68 and the region around the object to be heated 48, only a rare gas such as Ar gas exists as the silicon-containing gas, the chlorine-containing gas, and the carrier gas, and the carbon-containing gas and silicon Since there is no reducing gas for reducing the contained gas, silicon carbide film formation can be suppressed, and the possibility of particle generation associated therewith can be suppressed. In addition, since this region is silicon-rich, it is possible to form a film of Si alone, that is, to form a silicon film. However, since the reaction chamber is heated to a melting point of silicon (about 1400 ° C.) or more, silicon It is considered that film formation is difficult to form.
In the example of FIG. 8, a pair of first gas supply nozzles 60 and a pair of second gas supply nozzles 70 are arranged in the x direction of FIG. 60 is disposed outside the second gas supply nozzle 70, that is, on the heated object 48 side, and the first gas supply nozzles 60 and the second gas supply nozzles 70 are opposed to each other. It is not limited to this. That is, the pair of second gas supply nozzles 70 may be disposed outside the pair of first gas supply nozzles 60, that is, on the heated object 48 side. Even in this case, silicon (Si) and carbon (C) are efficiently mixed.
In addition, one first gas supply nozzle 60 and one second gas supply nozzle 70 are arranged so as to face each other in the x direction in FIG. The gas supply nozzle 60 and one second gas supply nozzle 70 can also be arranged so as to be opposite to the arrangement of the outer gas supply nozzles. In this case, since the arrangement order of the inner gas supply nozzle and the outer gas supply nozzle is reversed, silicon (Si) and carbon (C) are efficiently mixed.

FIG. 9 shows the result of calculating the degree of mixing of the supplied silicon-containing gas and carbon-containing gas when using the double opposed nozzle of the first embodiment of the present invention.
FIG. 9 shows a silicon-containing gas and a carbon-containing gas supplied from the first gas supply port 68 and the second gas supply port 72 to the reaction chamber in the double-facing nozzle of the first embodiment, respectively. It is the result of carrying out the flow analysis about the mixing degree of gas and carbon containing gas.
In FIG. 9, the value indicating the degree of mixing of silicon and carbon is the product of the concentration of the silicon-containing gas and the concentration of the carbon-containing gas ([Si] × [C]), and [Si] × [C] is The closer the value is to zero, that is, the region containing only a silicon-containing gas or a carbon-containing gas is shown in darker color, and the closer [Si] × [C] is to the value of 1, that is, silicon. A region where the contained gas and the carbon-containing gas are sufficiently mixed and present is shown in a lighter color.
The silicon carbide film is preferably formed by consuming a silicon-containing gas and a carbon-containing gas at a ratio of 1: 1. That is, by sufficiently mixing the silicon-containing gas and the carbon-containing gas so that they are consumed at a ratio of 1: 1, a silicon carbide epitaxial film can be uniformly formed on the wafer 14 as a substrate. The film formation rate can also be increased.
In FIG. 9, the silicon-containing gas supplied from the first gas supply port 68 and the carbon-containing gas supplied from the second gas supply port 72 are mixed after being supplied to the reaction region, respectively. It can be seen that the mixture is uniformly mixed before reaching a certain wafer 14. Thereby, the reaction contributing gas efficiently mixed into the wafer 14 can be supplied, and the silicon carbide epitaxial film can be uniformly formed on the wafer 14.
Further, it can be seen that the silicon-containing gas and the carbon-containing gas have a low degree of mixing immediately after being ejected, and are mixed as they approach the wafer 14 that is the substrate. Accordingly, the formation of a silicon carbide film is suppressed in the vicinity of the first gas supply port 68 or the second gas supply port 72, and the accompanying deposition of the silicon carbide film and the deposited silicon carbide film are prevented. Generation of particles due to peeling can also be suppressed.

FIG. 10A shows an example of a horizontal sectional view of the semiconductor manufacturing apparatus 10 according to the first embodiment of the present invention as viewed from above. In the case of the double opposed nozzle shown in FIG. 10A, the gas supply ports 68 of the silicon-containing gas or the gas supply ports 72 of the carbon-containing gas are opposed to each other. In other words, the reaction contributing gas reaches the wafer surface without having a concentration deviation in the x direction in the figure, and the deviation between the silicon-containing gas concentration and the carbon-containing gas concentration in the wafer 14 can be reduced. I can do it.
FIG. 10B shows the concentration of the carbon-containing gas and the silicon-containing gas at each position on the monitor line from the result of the flow analysis along the monitor line indicated by the broken line of the wafer 14 in FIG. The ratio (C / Si) and the growth rate of the formed silicon carbide film are shown respectively.
In FIG. 10B, C / Si, which is the concentration ratio between the carbon-containing gas and the silicon-containing gas at each position on the monitor line in FIG. The deposition rate of the silicon epitaxial film is indicated by a triangle mark (▲). The vertical axis on the left is the deposition rate (relative unit), the vertical axis on the right is C / Si (relative unit) which is the concentration ratio of carbon and silicon, and the horizontal axis is the position on the monitor line in FIG.
In FIG. 10B, the value of the film formation rate and the value of C / Si at each position on the monitor line are almost constant regardless of the position. It can be seen that the concentration of silicon and carbon in the film is not biased and can be uniformly formed on the wafer 14 without being biased.

As for the arrangement of the gas supply nozzles, it has already been mentioned that silicon and carbon are well mixed regardless of whether the first gas supply nozzle 60 is arranged outside or inside the second gas supply nozzle 70. It is more desirable to dispose the first gas supply nozzle 60 outside the second gas supply nozzle 70. In this respect, when the first gas supply nozzle 60 is arranged outside the second gas supply nozzle 70 (first embodiment), the first gas supply nozzle 60 is arranged inside the second gas supply nozzle 70. The case will be described using the concentration ratio (C / Si) between the carbon-containing gas and the silicon-containing gas in the case of (1) (modified example A of the first embodiment). In the modified example A, as in the first embodiment, the first gas supply nozzles 60 face each other, the second gas supply nozzles 70 face each other, and the gas supply ports 68 of the silicon-containing gas also face each other. Are opposed to each other, and the gas supply ports 72 of the carbon-containing gas are opposed to each other.
FIG. 10C shows the concentration ratio between the carbon-containing gas and the silicon-containing gas in the first embodiment and modification A at each position on the monitor line indicated by the broken line of the wafer 14 in FIG. C / Si). FIG. 10C shows the result of flow analysis. In FIG. 10C, the concentration ratio (C / Si) of the first embodiment is indicated by a circle (●), and the concentration ratio (C / Si) of Modification A is indicated by a triangle (▲). . The vertical axis is C / Si (relative unit) which is the concentration ratio of carbon and silicon, and the horizontal axis is the position on the monitor line in FIG.
In FIG. 10C, the concentration ratio (C / Si) of the first embodiment is substantially constant at each position on the monitor line, and the concentration ratio (C / Si) of Modification A is on the monitor line. Slightly lower at both ends. Therefore, it can be said that the first embodiment has better uniformity of the concentration ratio (C / Si) than the modification A.

The reason why the uniformity of the concentration ratio (C / Si) in the first embodiment is better than that of Modification A is considered as follows.
As described above, the supply amount of the reducing gas, for example, hydrogen gas, supplied from the second gas supply port 72 together with the carbon-containing gas is preferably very large compared to the silicon-containing gas and the chlorine-containing gas. . Therefore, when the first gas supply nozzle 60 (silicon-containing gas) is arranged inside the second gas supply nozzle 70 (hydrogen gas) as in Modification A, the silicon-containing gas and the carbon-containing gas are flow rates. It is pushed by the flow of hydrogen gas having a large amount and is carried onto the wafer without being sufficiently mixed as in the first embodiment. Conversely, when the first gas supply nozzle 60 (silicon-containing gas) is arranged outside the second gas supply nozzle 70 (hydrogen gas) as in the first embodiment, the silicon-containing gas swirls. Gradually toward the second gas supply nozzle 70 side, the silicon-containing gas and the carbon-containing gas are sufficiently mixed and carried onto the wafer by the flow of hydrogen gas. In this way, in the first embodiment, the uniformity of the concentration ratio (C / Si) is better than that of Modification A.

According to the first embodiment, at least one of the following effects is achieved. By providing the double opposed nozzle of the first embodiment,
(1) By supplying at least a silicon-containing gas and a chlorine-containing gas from the first gas supply port 68 and supplying at least a carbon-containing gas and a reducing gas from the second gas supply port 72, the inside of the gas supply nozzle It is possible to suppress the formation of a deposited film at the same time.
(2) According to the above (1), consumption of gas as a raw material in the gas supply nozzle can be suppressed, and silicon carbide epitaxial films upstream and downstream of the first and second gas supply nozzles in the reaction chamber 44 The film can be grown uniformly.
(3) According to the above (1), the clogging in the nozzle due to the growth of the deposited film in the nozzle can be suppressed.
(4) Further, it is possible to suppress the occurrence of a problem of particle increase in the reaction chamber 44 or particle adhesion to the wafer 14 due to separation or desorption of deposits in the nozzle.
(5) The formation of a silicon carbide film on the wall surface in the processing region can be suppressed, and the generation of particles associated therewith can be suppressed.
(6) The deviation of the concentration of the carbon-containing gas and the concentration of the silicon-containing gas in the plane of the wafer can be reduced, thereby improving the in-plane uniformity of the film thickness of the silicon carbide epitaxial film.
(7) Due to the above effects, a silicon carbide epitaxial film can be grown on a large number of substrates in a single process.

[Second Embodiment]
Next, a second embodiment will be described.
The second embodiment is a modification of the first embodiment, and includes a first gas supply nozzle 60 and a second gas supply nozzle 70, respectively, and a first gas supply port 68 and a second gas supply port 72. Then, the silicon-containing gas and the carbon-containing gas were efficiently mixed and then supplied to the wafer 14 as the substrate, and the shape of the gas supply nozzle for forming the silicon carbide epitaxial film was examined.

FIG. 11 shows an example thereof. As shown in FIG. 11, for example, a cylindrical first gas supply nozzle 60 is provided in parallel (illustrated as two in FIG. 11), and one first gas supply is provided. A first gas supply port 68 provided in one or more nozzles 60 and a first gas supply port 68 provided in one or more other gas supply nozzles 60 are opposed to each other; and For example, a second gas supply nozzle 70 having a cylindrical shape is provided in parallel (illustrated as two in FIG. 11), and one or more second gas supply ports 72 provided in one second gas supply nozzle 70 and The other second gas supply nozzle 70 is provided so as to face one or more second gas supply ports 72.
Accordingly, the silicon-containing gas and the carbon-containing gas can be sufficiently mixed before reaching the substrate, and a uniform silicon carbide epitaxial film can be formed on the wafer 14 that is the substrate.
In addition, the gas supply nozzle can be easily manufactured as compared with the shape of the gas supply nozzle of the first embodiment.

  At this time, as shown in FIG. 11, the second gas supply nozzle 70 is preferably provided between the wafer 14 and the first gas supply nozzle 60, so that the silicon-containing gas and the chlorine-containing gas The carbon-containing gas can be mixed efficiently. In addition, it is possible to suppress the formation of a film near the first gas supply port in the reaction chamber.

Preferably, the first gas supply nozzle 60 and the second gas supply nozzle 70 are formed between the first gas supply nozzle 60 and the inner wall of the heated body 48 or the first gas supply nozzle. 60 and the second gas supply nozzle 70 preferably have a shape that does not cause a gap. For example, the first gas supply nozzle 60 and the second gas supply nozzle 70 are polygonal or arcuate. It may be a shape.
Thereby, since it is possible to suppress the reaction contributing gas from entering the gap, the reaction contributing gas can be efficiently supplied to the wafer 14, and the formation of the silicon carbide film in the gap can be suppressed, and the The possibility that the silicon carbide film is peeled off to generate particles can be suppressed.

According to the second embodiment, in addition to the effects in the first embodiment, at least one or more of the following effects can be achieved.
(1) The gas supply nozzle can be easily manufactured.
(2) By (1), the running cost at the time of gas supply nozzle replacement | exchange can be reduced.

[Third embodiment]
Next, a third embodiment will be described.
The third embodiment is a modification of the first embodiment, in which a first gas supply nozzle 60 and a second gas supply nozzle 70 are provided, and a first gas supply port 68 is provided in the direction of the wafer 14. By making the second gas supply port 72 face each other, the silicon-containing gas and the carbon-containing gas are efficiently mixed and then supplied to the wafer 14 as a substrate to form a silicon carbide epitaxial film. The shape was examined.

  FIG. 12 shows an example. As shown in FIG. 12, for example, a first gas supply nozzle 60 having a cylindrical shape is provided (illustrated as one in FIG. 12). The first gas supply port 68 provided as described above is provided in the direction of the wafer 14, and the cylindrical second gas supply nozzle 70 is provided in parallel (illustrated as two in FIG. 11), and one second gas supply is provided. One or more second gas supply ports 72 provided in the nozzle 70 and the second gas supply port 72 provided in the other second gas supply nozzle 70 are provided so as to face each other.

  Thus, the silicon-containing gas and the carbon-containing gas can be sufficiently mixed before reaching the substrate, and a uniform silicon carbide epitaxial film can be formed on the wafer 14 that is the substrate. Further, since the first gas supply port 68 is provided in the direction of the wafer 14, the mixed gas of the mixed silicon-containing gas and carbon-containing gas is easily supplied in the direction of the wafer 14. Moreover, since the number of gas supply nozzles can be reduced, the number of parts can be reduced and the running cost can be reduced.

  At this time, as shown in FIG. 12, the second gas supply nozzle 70 is preferably provided between the wafer 14 and the first gas supply nozzle 60, whereby the silicon-containing gas, the chlorine-containing gas, and the carbon are added. The contained gas can be mixed efficiently. In addition, it is possible to suppress the formation of a film near the first gas supply port in the reaction chamber.

Preferably, the first gas supply nozzle 60 and the second gas supply nozzle 70 are formed between the first gas supply nozzle 60 and the inner wall of the heated body 48 or the first gas supply nozzle. 60 and the second gas supply nozzle 70 preferably have a shape that does not cause a gap. For example, the first gas supply nozzle 60 and the second gas supply nozzle 70 have a polygonal shape. Also good.
Thereby, since it is possible to suppress the reaction contributing gas from entering the gap, the reaction contributing gas can be efficiently supplied to the wafer 14, and the formation of a silicon carbide film in the gap can be suppressed. The possibility that the silicon carbide film is peeled off to generate particles can be suppressed.

According to 3rd Embodiment, in addition to the effect in 1st Embodiment and 2nd Embodiment, there exists at least 1 or more effect among the effects shown below.
(1) A mixed gas of silicon-containing gas and carbon-containing gas mixed can be efficiently supplied to the wafer 14 (2) Also, the number of gas supply nozzles can be reduced to constitute a substrate processing apparatus. The number of parts to be reduced can be reduced.

In addition, this invention is not limited to the said Example, It cannot be overemphasized that it can change variously in the range which does not deviate from the summary.
The description of this specification includes the following inventions.
That is, the first invention is
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrates in the reaction chamber and that is provided at least one at a position different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a semiconductor device in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
A step of carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. And a process of
Unloading the substrate from the reaction chamber;
A method for manufacturing a semiconductor device comprising:
With this configuration, compared with the case where the gas outflow direction of the first gas supply port and the gas outflow direction of the second gas supply port are not opposite to each other, the silicon-containing material supplied from the first gas supply port in the reaction chamber is contained. Since the gas and the carbon-containing gas supplied from the second gas supply port can be mixed before reaching the substrate, the carbon-containing gas and the silicon-containing gas in the wafer surface of the silicon carbide epitaxial film to be formed The semiconductor device having a better concentration ratio and C / Si ratio distribution (small Si / C ratio uneven distribution) can be manufactured. In addition, it is possible to suppress the formation of a film near the first gas supply port in the reaction chamber.
Note that the first gas supply nozzle and the second gas supply nozzle are preferably provided in a space between a heated body provided in the reaction chamber and a plurality of stacked substrates.

The second invention is
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply system for supplying at least a silicon-containing gas and a chlorine-containing gas into the reaction chamber;
A second gas supply system for supplying at least a carbon-containing gas and a reducing gas into the reaction chamber;
A first gas supply nozzle provided to extend to the array region of the substrates in the reaction chamber;
A second gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided at a position different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
The first gas supply system supplies at least silicon-containing gas and chlorine-containing gas from the first gas supply port into the reaction chamber, and the second gas supply system supplies the second gas supply port. A controller for supplying at least a carbon-containing gas and a reducing gas into the reaction chamber to control the formation of a silicon carbide film on the substrate;
With
The substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle.
With this configuration, compared with the case where the gas outflow direction of the first gas supply port and the gas outflow direction of the second gas supply port are not opposite to each other, the silicon-containing material supplied from the first gas supply port in the reaction chamber is contained. Since the gas and the carbon-containing gas supplied from the second gas supply port can be mixed before reaching the substrate, the carbon-containing gas and the silicon-containing gas in the wafer surface of the silicon carbide epitaxial film to be formed The semiconductor device having a better concentration ratio and C / Si ratio distribution (small Si / C ratio uneven distribution) can be manufactured. In addition, it is possible to suppress the formation of a film near the first gas supply port in the reaction chamber.
The first gas supply nozzle and the second gas supply nozzle are arranged in a direction perpendicular to the radial direction of the substrate and parallel to the substrate surface, and in a space until the outflowed gas reaches the wafer, It is preferable that the direction of the first gas supply port and the direction of the second gas supply port intersect.

The third invention is
A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrates in the reaction chamber and that is provided at least one at a position different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a substrate in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
A step of carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. And a process of
Unloading the substrate from the reaction chamber;
A method for manufacturing a substrate comprising:
With this configuration, compared with the case where the gas outflow direction of the first gas supply port and the gas outflow direction of the second gas supply port are not opposite to each other, the silicon-containing material supplied from the first gas supply port in the reaction chamber is contained. Since the gas and the carbon-containing gas supplied from the second gas supply port can be mixed before reaching the substrate, the carbon-containing gas and the silicon-containing gas in the wafer surface of the silicon carbide epitaxial film to be formed A substrate with a better concentration ratio and C / Si ratio distribution (small Si / C ratio uneven distribution) can be manufactured. In addition, it is possible to suppress the formation of a film near the first gas supply port in the reaction chamber.

According to a fourth invention, in the second invention,
The substrate processing apparatus, wherein the first gas supply port is provided with a height different from that of the second gas supply port.
With this configuration, the mixing efficiency of the gas ejected from the gas supply port can be improved.

According to a fifth invention, in the second invention,
The direction of the first gas supply port and the direction of the second gas supply port intersect in a space before the gas flowing out from the first gas supply port and the second gas supply port reaches the substrate. A substrate processing apparatus provided to perform.
With this configuration, after the gas contributing to the reaction supplied from the first gas supply port and the second gas supply port is sufficiently mixed, it can be efficiently supplied to the substrate.

A sixth invention is the second invention, wherein:
A substrate processing apparatus, wherein a direction in which the first gas supply port is provided and a direction in which the second gas supply port is provided are provided in parallel with the surface of the substrate.
With this configuration, the gas contributing to the reaction supplied from the first gas supply port and the second gas supply port can be efficiently supplied to the substrate.

Further, in the fourth invention, when two or more first gas supply nozzles or two or more second gas supply nozzles are provided in the reaction chamber, the height position of the first gas supply port provided in each of them. May be made different.
Also with this configuration, it is possible to improve the mixing efficiency of the gas ejected from the gas supply port.

  In the first to sixth inventions, at least the silicon-containing gas and the chlorine-containing gas are supplied from the first gas supply port provided in the first gas supply nozzle, and the second gas supply nozzle Although at least the carbon-containing gas and the reducing gas are supplied from the second gas supply port provided in the first gas supply port, at least the silicon-containing gas is supplied from the first gas supply port provided in the first gas supply nozzle. And at least a carbon-containing gas from a second gas supply port provided in the second gas supply nozzle.

  In the first to sixth inventions, the dopant gas for controlling the impurity concentration of the substrate is supplied from at least one of the first gas supply nozzle and the second gas supply nozzle, or You may make it supply from gas supply nozzles other than a said 1st gas supply nozzle and a said 2nd gas supply nozzle.

  DESCRIPTION OF SYMBOLS 10 ... Substrate processing apparatus, 14 ... Wafer, 12 ... Housing | casing, 16 ... Pod, 18 ... Pod stage, 22 ... Pod accommodation shelf, 28 ... Substrate transfer machine, 30 ... Boat, 40 ... Processing furnace, 42 ... Reaction tube 44 ... reaction chamber, 48 ... heated object, 50 ... induction coil, 54 ... heat insulating material, 60 ... first gas supply nozzle, 68 ... first gas supply port, 70 ... second gas supply nozzle, 72 2nd gas supply port, 90 ... 1st gas exhaust port, 91 ... Manifold, 93 ... Pressure sensor, 102 ... Seal cap, 152 ... Controller, 210a ... Silicon-containing gas supply source, 210b ... Chlorine-containing gas supply source 210c ... a carbon-containing gas supply source, 210d ... a reducing gas supply source, 210e ... an inert gas supply source, 211a, 211b, 211c, 211d, 211e ... MFC, 212a, 212b, 21 c, 212d, 212e ... open / close valve, 214 ... APC valve, 218 ... boat rotation mechanism, 220 ... vacuum pump, 222 ... first gas supply pipe, 260 ... second gas supply pipe, 240 ... third gas supply Pipe, 230 ... gas exhaust pipe, 360 ... third gas supply port, 390 ... second gas exhaust port.

Claims (4)

A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at one or more positions different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a semiconductor device in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
Carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. Forming, and
Unloading the substrate from the reaction chamber;
A method for manufacturing a semiconductor device comprising: A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply system for supplying at least a silicon-containing gas and a chlorine-containing gas into the reaction chamber;
A second gas supply system for supplying at least a carbon-containing gas and a reducing gas into the reaction chamber;
A first gas supply nozzle provided to extend to the array region of the substrate in the reaction chamber;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at a position different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
The first gas supply system supplies at least a silicon-containing gas and a chlorine-containing gas from the first gas supply port into the reaction chamber, and the second gas supply system supplies the second gas supply. A controller for controlling at least a carbon-containing gas and a reducing gas to be formed from the mouth into the reaction chamber so that a silicon carbide film is formed on the substrate;
With
The substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle. A reaction chamber in which substrates are stacked in a vertical direction at a predetermined interval; and
A first gas supply nozzle that extends to the array region of the substrates in the reaction chamber and is provided with one or more;
A second gas supply nozzle that extends to the array region of the substrate in the reaction chamber and is provided at one or more positions different from the first gas supply nozzle;
A first gas supply port provided at least one in the first gas supply nozzle;
A second gas supply port provided at least one in the second gas supply nozzle;
With
A method of manufacturing a substrate in a substrate processing apparatus, wherein the second gas supply nozzle is provided between the substrate and the first gas supply nozzle,
Carrying the substrates arranged in a vertical direction at predetermined intervals into the reaction chamber;
At least a silicon-containing gas and a chlorine-containing gas are supplied from the first gas supply port, and at least a carbon-containing gas and a reducing gas are supplied from the second gas supply port to form a silicon carbide film on the substrate. Forming, and
Unloading the substrate from the reaction chamber;
A method for manufacturing a substrate comprising:   The substrate processing apparatus according to claim 2, wherein the first gas supply port is provided with a height different from that of the second gas supply port.

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