JP2012044060A - Substrate processing device - Google Patents

Abstract

Provided is a substrate processing apparatus capable of detecting the arrangement state of a substrate even when a substrate having high light transmittance is used.
A reaction chamber for processing a substrate, a substrate holder for holding the substrate holder on which the substrate is placed and being disposed in the reaction chamber during substrate processing, and the substrate placed on the substrate holder. A substrate transfer device 11 that conveys the substrate holder in a state where the substrate holder is transferred. The substrate transfer device 11 includes an arm 13 that holds the substrate holder, a first light projecting unit that projects light, and the A first fiber sensor having a first light receiving portion for receiving light projected from the first light projecting portion, and the arm 13 normally holds the substrate holder in the first fiber sensor. The substrate holder is positioned between the first light projecting unit and the first light receiving unit.
[Selection] Figure 1

Description

  The present invention relates to a substrate processing apparatus having a step of processing a substrate, a semiconductor device manufacturing method, and a substrate manufacturing method.

  Silicon carbide (hereinafter referred to as SiC) has attracted attention as a power device element material because it has a larger energy band gap and higher insulating properties than silicon (hereinafter referred to as Si). On the other hand, it is known that SiC has a higher melting point than Si, does not have a liquid phase under normal pressure, and has a small impurity diffusion coefficient, so that it is difficult to produce a crystal substrate or a device.

  Conventional substrate processing apparatuses for forming an SiC epitaxial film are mainly substrate processing apparatuses called “pancake type” and “planetary type” as shown in FIG. 13 and FIG. As shown in FIG. 4, several to dozen or so SiC substrates (hereinafter referred to as wafers) 91 are arranged in a plane on a plate-like susceptor 92, or the SiC wafer 91 is held by the susceptor 92 and 1500 ° C. The raw material gas used for film formation is supplied into the reaction chamber 94 from one place through the gas supply port 93 by heating to ˜1800 ° C., and an SiC epitaxial film is grown on the upper surface of the wafer 91 (wafer main surface). .

  The source gas is generally supplied from the central portion of the reaction chamber 94 for processing the wafer 91 and is exhausted from the peripheral portion. The gas concentration distribution from the gas supply port 93 to the gas exhaust port 95 is as follows. Because of the large change, the wafer 91 and the susceptor 92 are generally rotated during film formation so as to avoid non-uniformity in film thickness.

  However, in the case of a conventional substrate processing apparatus, when processing a large number of wafers 91 or when increasing the diameter of the wafer 91, it is necessary to increase the diameter of the susceptor 92, so that the substrate processing apparatus becomes larger. Further, the floor area of the reaction chamber 94 is increased and the cost is increased. Further, when two or more wafers 91 are arranged in the radial direction from the gas supply port 93 of the source gas, a film thickness difference is generated between the processing wafers 91 due to the above-described gas concentration difference problem. There was a problem that the number of sheets was limited.

  On the other hand, although it is not a substrate processing apparatus for forming a SiC epitaxial film, it is a vertical substrate processing apparatus that can process a plurality of (for example, 25 to 100) wafers at a time with a footprint equivalent to one wafer. There is a device. The vertical substrate processing apparatus has a structure capable of automatically transporting a wafer as described in Patent Document 2, and transfers an unprocessed substrate to a substrate holder (boat) loaded in a reaction chamber. A substrate transfer machine for transferring processed wafers from a boat is provided with a fiber sensor that can detect the presence or absence of a wafer.

JP 2006-196807 A JP 2000-91255 A

  Here, considering that the SiC wafer is automatically transferred using a substrate transfer machine, the light transmittance of the SiC wafer becomes a problem as described in Patent Document 2. That is, the SiC wafer is highly transmissive to visible light and infrared light and may not respond to the sensor. In Patent Document 2, the SiC wafer is used as a dummy wafer. By using a SiC dummy wafer having a low transmittance with respect to the light source light of the photosensor installed in the transfer device, the wafer is removed from the wafer cassette. When transferring dummy wafers to a boat and transferring dummy wafers from a wafer boat to a wafer cassette, the number and arrangement of dummy wafers are detected and monitored.

  However, when the SiC wafer itself is the object to be processed, it is difficult to adopt it in order to maintain the quality if the light transmittance is intentionally reduced as shown in Patent Document 2. Therefore, there is a possibility that the fiber light of the fiber sensor passes through the SiC wafer and cannot be detected well, and it is difficult to detect the SiC wafer by the fiber sensor. In addition, the same problem arises when using a wafer with high light transmittance like a SiC wafer.

  In view of such circumstances, the present invention provides a substrate processing apparatus capable of detecting the arrangement state of a substrate even when a substrate having high light transmittance is used.

  The present invention relates to a reaction chamber for processing a substrate, a substrate holder on which the substrate is placed, a substrate holder that is disposed in the reaction chamber during substrate processing, and a state in which the substrate is placed on the substrate holder And a substrate transfer machine for carrying the substrate holder, the substrate transfer machine having an arm for holding the substrate holder, a first light projecting unit for projecting light, and the first light projecting unit. A first fiber sensor having a first light receiving unit that receives light projected from the unit, and the first fiber sensor is configured so that the arm normally holds the substrate holder. The present invention relates to a substrate processing apparatus arranged so that the substrate holder is positioned between the first light projecting unit and the first light receiving unit.

  According to the present invention, malfunction of the substrate processing apparatus can be prevented.

It is a perspective view of the substrate processing apparatus in the present invention. It is a general | schematic elevation sectional drawing which shows the processing furnace in this invention. It is a block diagram which shows the structure of the controller in this invention. It is a perspective view which shows the board | substrate transfer machine in the 1st Example of this invention. It is a schematic explanatory drawing which shows the structure of the wafer holder in the 1st Example of this invention. It is a schematic explanatory drawing which shows the detection method of the wafer holder in 1st Example of this invention. It is a schematic explanatory drawing which shows the modification of the 1st Example of this invention. It is a schematic explanatory drawing which shows the detection method of the wafer holder in the 2nd Example of this invention. The shape of the wafer holder in the 3rd example of the present invention is shown, (A) is a schematic diagram of an upper wafer holder and (B) is a schematic diagram of a lower wafer holder. It is a schematic explanatory drawing which shows the detection method of the wafer holder in the 3rd Example of this invention. The shape of the wafer holder in the modification of the 3rd Example of this invention is shown, (A) is the schematic of an upper wafer holder, (B) is the schematic of a lower wafer holder. It is a schematic explanatory drawing which shows the detection method of the wafer holder in the modification of the 3rd Example of this invention. It is a schematic sectional elevation showing a conventional pancake-type substrate processing apparatus. It is a schematic elevation sectional view showing a conventional planetary type substrate processing apparatus. It is a schematic plan sectional view showing a conventional substrate processing apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, referring to FIG. 1, an example of a substrate processing apparatus 1 for forming a SiC epitaxial film in the first embodiment of the present invention will be described.

  The substrate processing apparatus 1 is a batch type vertical heat treatment apparatus and has a housing 2 in which a main part is arranged. In the substrate processing apparatus 1, a hoop (hereinafter referred to as a pod) 4 is used as a wafer carrier as a hermetically sealed substrate container for accommodating a wafer 3 (see FIG. 2) as a substrate made of, for example, SiC. Is done. A pod stage 5 is disposed on the front side of the casing 2, and the pod 4 is conveyed to the pod stage 5. For example, 25 wafers 3 are stored in the pod 4 while being individually held by a wafer holder (not shown), and set on the pod stage 5 with the lid closed.

  A pod transfer device 6 is disposed at a position in front of the housing 2 and facing the pod stage 5. Further, a pod storage shelf 7, a pod opener 8, and a substrate number detector 9 are disposed in the vicinity of the pod transfer device 6. The pod storage shelf 7 is disposed above the pod opener 8 and is configured to hold a plurality of pods 4 mounted thereon. The substrate number detector 9 is disposed adjacent to the pod opener 8, and the pod transfer device 6 transfers the pod 4 among the pod stage 5, the pod storage shelf 7, and the pod opener 8. The pod opener 8 opens the lid of the pod 4, and the substrate number detector 9 detects the number of wafers 3 in the pod 4 with the lid opened.

  A substrate transfer machine 11 and a boat 12 as a substrate holder are arranged in the housing 2. The substrate transfer device 11 has an arm (tweezer) 13 and a fiber sensor (not shown) that can detect the presence or absence of the wafer 3, and has a structure that can be moved back and forth, raised and lowered by a driving means (not shown), and rotatable. ing. The arm 13 can take out, for example, five wafers 3 together with the wafer holder, and the pod 4 and the boat 12 placed at the position of the pod opener 8 by the cooperation of the advance / retreat, elevation, and rotation of the arm 13. The wafer 3 is transferred.

  The boat 12 is made of a heat-resistant material such as carbon graphite and SiC, for example, so that a plurality of wafers 3 are aligned in a horizontal posture and aligned with each other in the vertical direction, and stacked and held in the vertical direction. It is configured. In addition, a boat heat insulating portion 14 (see FIG. 2) is arranged as a cylindrical heat insulating member made of a heat resistant material such as quartz or SiC at the lower portion of the boat 12. It is configured such that heat from a certain susceptor 15 is difficult to be transmitted to the lower side of the processing furnace 16 (see FIG. 2).

  The processing furnace 16 is disposed in the upper part on the back side in the housing 2. The boat 12 loaded with a plurality of wafers 3 is loaded into the processing furnace 16 and a film forming process is performed.

  Next, the processing furnace 16 of the substrate processing apparatus 1 for forming a SiC epitaxial film will be described with reference to FIG. A first gas supply nozzle 18 having a first gas supply port 17 for supplying at least a Si (silicon) atom-containing gas, a Cl (chlorine) atom-containing gas, and a carrier gas, at least a C (carbon) atom-containing gas. A second gas supply nozzle 21 and a first gas exhaust nozzle 22 each having a second gas supply port 19 for supplying gas and a carrier gas are shown as representative examples. Further, a third gas supply nozzle 23 for supplying an inert gas and an exhaust duct 24 as a second gas exhaust pipe are shown.

  The processing furnace 16 includes a cylindrical reaction tube 25. The reaction tube 25 is made of a heat-resistant material such as quartz or SiC, and is formed in a cylindrical shape having a closed upper end and an opened lower end. A reaction chamber 26 is defined in a cylindrical hollow portion inside the reaction tube 25, and the wafers 3 as substrates made of Si or SiC or the like are placed in a horizontal posture by the boat 12 and aligned with each other in the center. They are arranged so that they can be stored in a state where they are aligned, stacked in the vertical direction, and held.

  Below the reaction tube 25, a manifold 27 is disposed concentrically with the reaction tube 25. The manifold 27 is made of, for example, stainless steel and is formed in a cylindrical shape having an upper end and a lower end opened. The manifold 27 is provided so as to support the reaction tube 25, and an O-ring (not shown) as a seal member is provided between the manifold 27 and the reaction tube 25. Since the manifold 27 is supported by a holding body (not shown), the reaction tube 25 is installed vertically. A reaction vessel is formed by the reaction tube 25 and the manifold 27.

  The processing furnace 16 includes the susceptor 15 to be heated and a dielectric coil 28 as a magnetic field generator. The susceptor 15 is disposed in the reaction chamber 26, and the dielectric coil 28 is supported by a support column 29 provided outside the reaction tube 25. The support column 29 is erected on the heater base 31 and is made of an insulating material such as alumina or ceramic. The susceptor 15 is heated by a magnetic field generated by the dielectric coil 28, and the reaction chamber 26 is heated when the susceptor 15 generates heat.

  In the vicinity of the susceptor 15, a temperature sensor (not shown) is provided as a temperature detector for detecting the temperature in the reaction chamber 26. The dielectric coil 28 and the temperature sensor are electrically connected to a temperature control unit 32 (see FIG. 3), and the degree of energization to the dielectric coil 28 is adjusted based on temperature information detected by the temperature sensor. Thus, the temperature in the reaction chamber 26 is controlled at a predetermined timing so as to have a desired temperature distribution.

  In the reaction chamber 26, the first and second gas supply nozzles 18 and 21 and the first gas exhaust nozzle 22 are disposed between the susceptor 15 and the boat 12. By providing a structure (not shown) that fills the space between the susceptor 15 and the boat 12, the gas supplied from the first and second gas supply nozzles 18, 21 is supplied to the susceptor. It is possible to prevent the wafer 3 from bypassing along the inner wall 15. When the structure is preferably made of a heat insulating material or carbon felt, heat resistance and generation of particles can be suppressed.

  Between the reaction tube 25 and the susceptor 15, for example, a heat insulating material 33 made of carbon felt or the like that is difficult to be dielectric is provided. By providing the heat insulating material 33, heat of the susceptor 15 is transferred to the reaction tube. 25 or transmission to the outside of the reaction tube 25 can be suppressed.

  A quartz-made liner tube 34 is provided between the reaction tube 25 and the dielectric coil 28. A scavenger is provided below the heater base 31 so as to surround the manifold 27. 35, and the liner tube 34 and the scavenger 35 prevent carrier gas such as H2 from leaking out of the reaction chamber 26 to prevent explosion. The space between the reaction tube 25 and the liner tube 34 and the space between the scavenger 35 and the manifold 27 are made the same atmosphere with the heater base 31 as a boundary.

  In the space between the reaction tube 25 and the liner tube 34, the third gas supply nozzle 23 that penetrates the liner tube 34 and extends upward is provided. The exhaust duct 24 is connected to the heater base 31, and the space between the reaction tube 25 and the liner tube 34 and the inside of the scavenger 35 are passed through holes (not shown) formed in the heater base 31. The exhaust duct 24 communicates with the exhaust duct 24 and can be exhausted through the exhaust duct 24. The exhaust duct 24 is provided with a gas detector 36. The gas detector 36 detects leakage of O2 and H2, thereby preventing explosion due to air mixing.

  In addition, an outer heat insulating wall 37 having a water cooling structure, for example, is provided outside the dielectric coil 28 so as to prevent the heat in the reaction chamber 26 from being transmitted to the outside so as to surround the reaction chamber 26. ing. Further, a magnetic seal 38 is provided outside the outer heat insulating wall 37 to prevent the magnetic field generated by the dielectric coil 28 from leaking outside.

  As shown in FIG. 2, at least a Si (silicon) atom-containing gas, a Cl (chlorine) atom-containing gas, and a carrier gas such as H2 are supplied between the susceptor 15 and the wafer 3. At least one first gas supply port 17 provided in one gas supply nozzle 18 is installed, and in a place different from the first gas supply nozzle 18, a C (carbon) atom-containing gas, H2, etc. The second gas supply port 19 and the first gas exhaust nozzle 22 provided at least one for the second gas supply nozzle 21 are disposed, and the reaction tube 25 and the liner tube are provided. 34, the third gas supply nozzle 23 is arranged.

  The first gas supply port 17 is made of, for example, carbon graphite and is provided in the reaction chamber 26, and the first gas supply nozzle 18 is attached to the manifold 27 so as to penetrate the manifold 27. ing. The first gas supply port 17 includes, for example, tetrachlorosilane (hereinafter referred to as SiCl4) as a Si (silicon) atom-containing gas including at least a Cl (chlorine) atom-containing gas, and hydrogen (hereinafter referred to as H2) as a carrier gas. Gas) is circulated through the first gas supply nozzle 18 and supplied into the reaction chamber 26. A plurality of the first gas supply nozzles 18 may be provided, and the Si (silicon) atom-containing gas and the Cl (chlorine) atom-containing gas are separated from each other as propane (C3 H8) and hydrogen chloride (HCl). You may supply as this gas.

  The first gas supply nozzle 18 is connected to a first gas line 39. The first gas line 39 is connected to, for example, gas pipes 41a and 41b. The gas pipes 41a and 41b are mass flow controllers (hereinafter referred to as MFCs) as flow rate controllers (flow rate control means) for H2 gas and SiCl4 gas, respectively. ) 42a, 42b and valves 43a, 43b are connected to, for example, an H2 gas supply source 44a and an SiCl4 gas supply source 44b.

  With the above-described configuration, for example, the supply flow rate, concentration, and partial pressure of H2 gas and SiCl4 gas can be controlled in the reaction chamber 26. The valves 43a and 43b and the MFCs 42a and 42b are electrically connected to a gas flow rate control unit 45 (see FIG. 3), and at a predetermined timing so that the flow rate of the supplied gas becomes a predetermined flow rate. It is designed to be controlled. The gas supply sources 44a and 44b, the valves 43a and 43b, the MFCs 42a and 42b, the gas pipes 41a and 41b, the first gas line 39, and the first gas supply nozzle for the H2 gas and the SiCl4 gas, respectively. 18 and at least one first gas supply port 17 provided in the first gas supply nozzle 18 constitute a first gas supply system as a gas supply system.

  Although SiCl4 gas is supplied as Si (silicon) atom-containing gas including Cl (chlorine) atom-containing gas, for example, trichlorosilane (hereinafter referred to as SiHCl3) gas or dichlorosilane (hereinafter referred to as SiH2 Cl2) gas is supplied. May be.

  The second gas supply port 19 is made of, for example, carbon graphite and is provided in the reaction chamber 26, and the second gas supply nozzle 21 is attached to the manifold 27 so as to penetrate the manifold 27. ing. The second gas supply port 19 is, for example, at least as a carrier gas, for example, hydrogen (single H atom or H2 molecule; hereinafter referred to as H2), and a C (carbon) atom-containing gas, for example, propane (hereinafter referred to as C3 H8). ) Gas is circulated through the second gas supply nozzle 21 and supplied into the reaction chamber 26. A plurality of the second gas supply nozzles 21 may be provided.

  The second gas supply nozzle 21 is connected to the second gas line 46. The second gas line 46 is connected to, for example, gas pipes 41c and 41d, and the gas pipes 41c and 41d are respectively connected to a carrier gas, for example, H2 gas through an MFC 42c and a valve 43c as flow rate control means. It is connected to an H2 gas supply source 44c and connected to a C3 H8 gas supply source 44d via a MFC 42d as a flow control means and a valve 43d for C3 H8 gas, for example, as a C (carbon) atom-containing gas.

  With the above configuration, for example, the supply flow rate, concentration, and partial pressure of H2 gas and C3 H8 gas can be controlled in the reaction chamber 26. The valves 43c and 43d and the MFCs 42c and 42d are electrically connected to the gas flow rate controller 45 (see FIG. 3), and are controlled at a predetermined timing so that the supplied gas flow rate becomes a predetermined flow rate. It has become like that. The gas supply sources 44c and 44d, the valves 43c and 43d, the MFCs 42c and 42d, the gas pipes 41c and 41d, the second gas line 46, and the second gas supply for the H2 gas and the C3 H8 gas, respectively. The nozzle 21 and the second gas supply port 19 constitute a second gas supply system as a gas supply system.

  The first gas exhaust nozzle 22 is disposed so as to face the positions of the first gas supply nozzle 18 and the second gas supply nozzle 21, and the manifold 27 includes the first gas exhaust nozzle 22. A gas exhaust pipe 47 connected to the gas exhaust nozzle 22 is provided so as to penetrate therethrough. A vacuum exhaust device 49 such as a vacuum pump is connected to the downstream side of the gas exhaust pipe 47 via a pressure sensor (not shown) as a pressure detector and an APC (Auto Pressure Controller) valve 48 as a pressure regulator. Yes. A pressure control unit 51 (see FIG. 3) is electrically connected to the pressure sensor and the APC valve 48. The pressure control unit 51 opens the APC valve 48 based on the pressure detected by the pressure sensor. The temperature is adjusted and controlled at a predetermined timing so that the pressure in the processing furnace 16 becomes a predetermined pressure.

  Below the processing furnace 16, a seal cap 52 is provided as a furnace port lid for hermetically closing the lower end opening of the processing furnace 16. The seal cap 52 is made of a metal such as stainless steel and is formed in a disk shape. An O-ring (not shown) is provided on the upper surface of the seal cap 52 as a seal material that contacts the lower end of the processing furnace 16. The seal cap 52 is provided with a rotation mechanism 53, and a rotation shaft 54 of the rotation mechanism 53 is connected to the boat 12 through the seal cap 52, and the wafer 12 is rotated by rotating the boat 12. It is configured to rotate.

  The seal cap 52 is configured as a lifting mechanism provided outside the processing furnace 16 so as to be vertically lifted by a lifting motor (not shown), and the boat 12 is driven by the lifting motor. It is possible to carry in / out the processing furnace 16. A drive control unit 55 (see FIG. 3) is electrically connected to the rotation mechanism 53 and the lifting motor, and is configured to control at a predetermined timing so as to perform a predetermined operation.

  In the above description, C3 H8 gas is exemplified as the C (carbon) atom-containing gas. However, ethylene (hereinafter referred to as C2 H4) gas or acetylene (hereinafter referred to as C2 H2) gas may be used.

  Moreover, although H2 gas was illustrated as carrier gas in the above, it is not restricted to this, H (hydrogen) atom containing gas, Ar (argon) gas, He (helium) gas, Ne (neon) gas, Kr (krypton) gas, At least one of rare gases such as Xe (xenon) gas may be used, or a mixed gas in which the above gases are combined may be used.

  Next, referring to FIG. 3, the control configuration of each part constituting the substrate processing apparatus 1 for forming a SiC epitaxial film will be described.

  The temperature control unit 32, the gas flow rate control unit 45, the pressure control unit 51, and the drive control unit 55 constitute an operation unit and an input / output unit, and serve as a main control unit 56 that controls the entire substrate processing apparatus 1. Electrically connected. The temperature control unit 32, the gas flow rate control unit 45, the pressure control unit 51, and the drive control unit 55 are configured as a controller 57.

  Next, a method of forming, for example, a SiC film on a substrate such as a wafer 3 made of SiC or the like as one step of a semiconductor device manufacturing process using the substrate processing apparatus 1 described above will be described. In the following description, the operation of each part constituting the substrate processing apparatus 1 is controlled by the controller 57.

  First, when the pod 4 storing a plurality of wafers 3 is set on the pod stage 5, the pod 4 is transferred from the pod stage 5 to the pod storage shelf 7 by the pod transfer device 6 and stocked. Next, the pod transport device 6 transports and sets the pod 4 stocked on the pod storage shelf 7 to the pod opener 8, opens the lid of the pod 4 by the pod opener 8, and sets the number of substrates. The number of wafers 3 stored in the pod 4 is detected by the detector 9.

  Next, the wafer transfer device 11 takes out the wafer 3 while being held by a wafer holder (described later) from the pod 4 at the position of the pod opener 8 and transfers it to the boat 12. At this time, whether or not the wafer 3 is held on the arm 13 is confirmed by a fiber sensor (described later) provided in the substrate transfer device 11. The wafer 3 is transported and integrated with the wafer holder, but the wafer holder and the wafer holder are hereinafter referred to as a wafer.

  When a plurality of wafers 3 are loaded into the boat 12, the boat 12 holding the wafers 3 is loaded into the reaction chamber 26 (boat loading) by a lift motor (not shown). In this state, the seal cap 52 seals the lower end of the manifold 27 via an O-ring (not shown).

  After carrying in the boat 12, the reaction chamber 26 is evacuated by the evacuation device 49 so that the inside of the reaction chamber 26 has a predetermined pressure (degree of vacuum). At this time, the pressure in the reaction chamber 26 is measured by a pressure sensor (not shown), and the APC valve 48 communicating with the first gas exhaust nozzle 22 is feedback-controlled based on the measured pressure. Further, the susceptor 15 is heated so that the wafer 3 and the reaction chamber 26 have a predetermined temperature. At this time, the state of energization to the dielectric coil 28 is feedback-controlled based on temperature information detected by a temperature sensor (not shown) so that the reaction chamber 26 has a predetermined temperature distribution. Subsequently, the boat 3 is rotated by the rotating mechanism 53, whereby the wafer 3 is rotated in the circumferential direction.

  Subsequently, SiCl4 gas that contributes to the SiC epitaxial growth reaction is supplied from the SiCl4 gas supply source 44b and is ejected into the reaction chamber 26 from the first gas supply port 17. Further, after the opening degrees of the MFCs 42c and 42d are adjusted so that the H2 gas and the C3 H8 gas have a predetermined flow rate, the valves 43c and 43d are opened, and the respective gases are supplied to the second gas. The gas flows through the line 46, flows through the second gas supply nozzle 21, and is introduced into the reaction chamber 26 through the second gas supply port 19.

  The gas supplied from the first gas supply port 17 and the second gas supply port 19 passes through the inside of the susceptor 15 in the reaction chamber 26, and the gas exhaust from the first gas exhaust nozzle 22. Exhaust through tube 47. When the gas supplied from the first gas supply port 17 and the second gas supply port 19 passes through the reaction chamber 26, the gas contacts the wafer 3 made of SiC or the like, and the surface of the wafer 3. A SiC epitaxial film is grown thereon.

  When a preset time elapses, the gas supply described above is stopped, an inert gas is supplied from an inert gas supply source (not shown), and the space inside the susceptor 15 in the reaction chamber 26 is inert gas. And the pressure in the reaction chamber 26 is returned to normal pressure.

  Thereafter, the seal cap 52 is lowered by the lifting motor, the lower end of the manifold 27 is opened, and the processed wafer 3 is held by the boat 12 from the lower end of the manifold 27 to the reaction tube 25. The boat 12 is made to stand by at a predetermined position until it is unloaded (boat unloading) and the wafer 3 held on the boat 12 is cooled. When the waiting wafer 3 of the boat 12 is cooled to a predetermined temperature, the substrate transfer device 11 takes out the wafer 3 from the boat 12, and the presence or absence of the wafer is confirmed by a fiber sensor. It is transported to and stored in an empty pod 4 set to 8. Thereafter, the pod 4 in which the wafer 3 is stored by the pod transfer device 6 is transferred to the pod storage shelf 7 or the pod stage 5. In this way, a series of operations of the substrate processing apparatus 1 is completed.

  Next, in FIG. 4 to FIG. 6, the detection of the wafer 3 when the wafer 3 is transferred by the substrate transfer machine 11 will be described.

  The substrate transfer machine 11 has a plurality (five in the figure) of the arms 13, and the arms 13 can hold a wafer holder 58 that holds the wafer 3 at the tip. A first fiber sensor 59 is provided in the vicinity (the base side of the arm 13 in FIG. 4).

  As shown in FIG. 5, the wafer holder 58 includes a lower wafer holder 61 and an upper wafer holder 62, at least one of which has heat resistance such as carbon graphite, and is made of an opaque material or a low light transmittance. It is formed by the material. The lower wafer holder 61 has a ring shape, and an inner peripheral portion is notched so that a wafer holding portion 63 having substantially the same diameter as the wafer 3 is formed at the center. The upper wafer holder 62 is a disk-shaped member having the same diameter as that of the lower wafer holder 61, and is substantially the same diameter as the wafer holding portion 63 in the center and at least the depth of the wafer holding portion 63. A disk-shaped convex portion 64 having a height lower than the plate thickness is formed, the wafer 3 is placed on the wafer holding portion 63, and the convex portion 64 is fitted to the wafer holding portion 63 so that the upper wafer holder By combining 62 with the lower wafer holder 61, the wafer 3 is held by the wafer holder 58.

  Since the film formation process is performed while the wafer 3 is held by the wafer holder 58, a portion exposed from the lower surface of the lower wafer holder 61 becomes a film formation surface, and a predetermined film thickness is formed on the film formation surface. A SiC epitaxial film is formed. Further, since the upper wafer holder 62 covers the upper surface opening of the lower wafer holder 61, it is possible to prevent particles from falling on the surface opposite to the film formation surface of the wafer 3.

  The first fiber sensor 59 includes a first light projecting unit 65 and a first light receiving unit 66. When the wafer holder 58 is held on the arm 13, the first light projecting unit 65 is provided. And the first light receiving unit 66 are provided at positions where the wafer holder 58 is sandwiched up and down, and fiber light is projected from the first light projecting unit 65 to the first light receiving unit 66. . Therefore, the wafer holder 58 is arranged so as to block the optical path between the first light projecting unit 65 and the first light receiving unit 66.

  When the unprocessed wafer 3 is transferred from the pod 4 to the boat 12 and the processed wafer 3 is transferred from the boat 12 to the pod 4 by the substrate transfer device 11, the first light projecting unit 65. Whether or not the wafer 3 is present is determined based on whether or not the first light receiving unit 66 can receive the fiber light emitted from the optical fiber.

  When the first light receiving unit 66 cannot receive the fiber light, that is, when the fiber light projected from the first light projecting unit 65 is blocked by the wafer holder 58, the wafer 3 is moved to the arm 13. It is determined that the data is normally held and the processing is continued.

  Further, when the first light receiving unit 66 receives the fiber light, that is, when the fiber light projected from the first light projecting unit 65 is not blocked by the wafer holder 58, the wafer 3 is It is determined that it is not held by the arm 13, the processing is interrupted, and the substrate processing apparatus 1 is stopped.

  As described above, in the step of transferring the wafer 3 by the substrate transfer machine 11, the presence or absence of the wafer holder 58 made of an opaque material that holds the wafer 3 instead of the wafer 3 by the first fiber sensor 59. Therefore, even if a material having high light transmittance such as SiC is used for the wafer 3, fiber light does not pass through the wafer holder 58 and the presence / absence of the wafer 3 is erroneously detected. There is nothing.

  Accordingly, although the wafer holder 58 is normally held by the arm 13, it is erroneously detected that the wafer holder 58 is not held, and the processing is interrupted due to a malfunction and the arm 13 is checked. A decrease can be prevented.

  In the first embodiment, the wafer holder 58 is made of carbon graphite. However, the material of the wafer holder 58 may be made of other materials as long as it has a light transmittance lower than that of the wafer 3. The effect of can be obtained.

  In addition, since the epitaxial film is formed on the SiC wafer 3 by the batch type substrate processing apparatus, the floor area of the reaction chamber 26 can be reduced as compared with the conventional pancake type or planetary type substrate processing apparatus. Can do.

  FIG. 7 shows a modification of the first embodiment. The first light projecting portion 65 and the first light receiving portion 66 of the first fiber sensor 59 in the first embodiment are shown in FIG. Either one (the first light projecting unit 65 in FIG. 7) is disposed on the side surface side of the wafer holder 58.

  In the above modification, the pitch between the arms 13 needs only to have a space for providing either one of the first light projecting unit 65 and the first light receiving unit 66. Therefore, the first fiber sensor 59 occupying space can be reduced, and the pitch between the arms 13 can be reduced.

  Furthermore, since the distance between the first light receiving portion 66 of the upper arm 13 and the first light projecting portion 65 of the lower arm 13 can be increased, malfunction of the first fiber sensors 59 can be prevented. Can do. In the first embodiment described above, if either one of the lower wafer holder 61 and the upper wafer holder 62 is opaque, the wafer holder 58 can be detected. If the lower wafer holder 61 is opaque, the wafer holder 58 can be detected.

  Next, a second embodiment of the present invention will be described with reference to FIG. 8 that are the same as those in FIG. 6 are given the same reference numerals, and descriptions thereof are omitted.

  In the second embodiment, a second fiber sensor 73 is further provided with respect to the first embodiment. Further, a lower through hole 67 which is a second through hole penetrating up and down outside the portion of the wafer holder 58 not holding the wafer 3, that is, outside the wafer holding portion 63 (see FIG. 5) of the lower wafer holder 61. And an upper through-hole 68 that is a third through-hole penetrating vertically is formed at a position that matches the lower through-hole 67 outside the convex portion 64 (see FIG. 5) of the upper wafer holder 62. The lower through hole 67 and the upper through hole 68 constitute a through hole 69 that is a first through hole that vertically penetrates the wafer holder 58.

  In the vicinity of the through hole 69, a second fiber sensor 73 including a second light projecting unit 71 and a second light receiving unit 72 is provided, and the second light projecting unit 71 and the second light receiving unit 72 are provided. Thus, the through hole 69 is sandwiched vertically, and the fiber light projected from the second light projecting unit 71 through the through hole 69 is received by the second light receiving unit 72. Yes.

  Since the wafer holder 58 has a two-part configuration of the lower wafer holder 61 and the upper wafer holder 62, the upper wafer holder 62 is displaced during the transfer by the substrate transfer machine 11 (see FIG. 1). There is.

  When the upper wafer holder 62 is displaced, the positions of the lower through hole 67 and the upper through hole 68 are displaced, so that the fiber light received by the second light receiving portion 72 is blocked, and the wafer holder 58 is displaced. Can be detected, and problems caused by film formation on the wafer 3 that is not normally held can be prevented.

  Further, even when not the upper wafer holder 62 but the entire wafer holder 58 is displaced, the fiber light received by the second light receiving unit 72 is blocked and an abnormality is detected.

  It should be noted that a member having high light transmittance such as quartz may be embedded in the lower through hole 67 and the upper through hole 68, respectively. In that case, since the lower through hole 67 and the upper through hole 68 can be closed, the gas flow condition and the heat conduction condition are determined according to the location where the lower through hole 67 of the lower wafer holder 61 is not formed. The uniformity in the processing of the wafer 3, particularly the in-plane film thickness uniformity of the wafer 3 can be improved.

  Further, since the second fiber sensor 73 can detect the displacement of the entire wafer holder 58, it is also applicable to a wafer holder that is not a two-part structure of the lower wafer holder 61 and the upper wafer holder 62. Is possible.

  If it is desired to detect not only the presence or absence of the wafer 3 but only the displacement of the upper wafer holder 62, the first fiber sensor 59 may be omitted and only the second fiber sensor 73 may be provided.

  Next, a third embodiment of the present invention will be described with reference to FIGS. 9 and 10, the same components as those in FIGS. 5 and 6 are denoted by the same reference numerals, and the description thereof is omitted.

  In the third embodiment, a notch 74 is formed at the peripheral edge of the lower wafer holder 61, and a protrusion 75 that can be engaged with the notch 74 is formed at the peripheral edge of the upper wafer holder 62.

  When holding the wafer 3 on the wafer holder 58, the wafer 3 is placed on the wafer holding part 63 of the lower wafer holder 61, and the convex part 64 of the upper wafer holder 62 is engaged with the wafer holding part 63. When the protruding portion 75 is engaged with the notched portion 74, the upper wafer holder 62 is united with the lower wafer holder 61.

  Further, a third fiber sensor 78 including a third light projecting unit 76 and a third light receiving unit 77 is provided in the vicinity of the cutout portion 74 and the protruding portion 75. One of the third light projecting unit 76 and the third light receiving unit 77 (the third light projecting unit 76 in FIG. 10) is arranged on the side surface side of the wafer holder 58, and the third light projecting unit 76 The fiber light projected from the light projecting unit 76 passes through the notch 74 and is received by the third light receiving unit 77, and the upper wafer holder 62 is mounted on the lower wafer holder 61. In this case, the fiber light projected from the third light projecting portion 76 is blocked by the projecting portion 75.

  When the wafer 3 is transferred by the substrate transfer device 11 (see FIG. 1), if a displacement such as the protrusion 75 climbs on the lower wafer holder 61 occurs, the third projection is performed. Since the fiber light projected from the light section 76 passes through the cutout section 74 and is received by the third light receiving section 77, the positional deviation of the upper wafer holder 62 can be detected.

  Further, the third fiber sensor 78 of the third embodiment blocks the fiber light projected from the third light projecting unit 76 in the normal state, and projects the light from the third light projecting unit 76 in the abnormal state. Since the optical fiber light is configured to be received by the third light receiving unit 77, the third fiber sensor 78 can detect the presence or absence of the wafer 3, and the first fiber sensor 59 can be omitted. .

  Further, since the lower wafer holder 61 and the upper wafer holder 62 are engaged with the cutout portion 74 and the protruding portion 75, unintentional rotational deviation can be prevented, and the upper wafer holder 61 and the upper wafer holder 62 can be prevented from being moved when engaged. By positioning the wafer holder 62, a highly reproducible film forming process can be performed.

  Further, when the notched portion 74 and the projecting portion 75 are engaged, the lower end of the projecting portion 75 and the lower surface of the lower wafer holder 61 are flush with each other, thereby allowing the gas flow. The condition of heat and the condition of heat conduction can be made the same as the part of the lower wafer holder 61 where the notched portion 74 is not formed, and the processing uniformity of the wafer 3, particularly the in-plane film thickness uniformity of the wafer 3. Can be improved.

  Further, in the third embodiment, since one of the third light projecting unit 76 and the third light receiving unit 77 is arranged on the side surface of the wafer holder 58, the first fiber sensor 59 is arranged on the side surface of the wafer holder 58 by placing either one of the first light projecting unit 65 and the first light receiving unit 66 in the same manner as the modification of the first embodiment. The space occupied by 59 can be reduced, and the pitch between the arms 13 (see FIG. 4) can be reduced.

  FIGS. 11 and 12 show a modification of the third embodiment. In this modification, the lower wafer holder 61 is vertically penetrated in the peripheral portion of the lower wafer holder 61 instead of the notch 74. A through hole 79 is formed, and a rod-like protrusion 81 that can be fitted into the through hole 79 is formed on the peripheral edge of the upper wafer holder 62 instead of the protrusion 75, and around the protrusion 81. A notch 82 is formed, and the protrusion 81 is inserted into the through hole 79 when the wafer 3 is held.

  The third fiber sensor 78 is provided such that the third light projecting portion 76 and the third light receiving portion 77 sandwich the through-hole 79 vertically, and the third light projecting portion 76 is provided. The fiber light projected from the light passes through the through hole 79 and is received by the third light receiving portion 77. When the upper wafer holder 62 is normally combined with the lower wafer holder 61, the fiber light projected from the third light projecting unit 76 is blocked by the upper wafer holder 62, and the upper wafer When the holder 62 is displaced, the fiber light projected from the third light projecting unit 76 is received by the third light receiving unit 77 through the notch 82.

  In the modified example, as in the third embodiment, the third light receiving unit 77 receives the fiber light projected from the third light projecting unit 76, so that the upper wafer holder 62 is displaced. Therefore, the presence / absence of the wafer holder 58 held by the arm 13 can also be detected, and the first fiber sensor 59 can be omitted.

  In addition, since the protrusion 81 is inserted into the through hole 79, the combined position of the lower wafer holder 61 and the upper wafer holder 62 is determined, and unintentional rotational deviation is prevented, so that reproducibility is high. Processing is possible.

  Furthermore, by replacing the notch 74 with the through-hole 79, the area of the lower surface opening of the lower wafer holder 61 can be reduced, so that the gas flow and the like can be made more uniform.

  In the first to third embodiments, the wafer holder 58 is made of carbon graphite. However, as long as the light transmittance is lower than that of the wafer 3, carbon graphite can be used. The same effect as that of the wafer holder 58 can be obtained. The wafer holder 58 is composed of two upper and lower members, but the upper and lower wafer holders may be integrally formed.

  Further, in the first to third embodiments, the processing using the SiC wafer 3 is described, but the wafer 3 may be made of other materials such as Si.

  Furthermore, in the first to third embodiments, the batch type vertical substrate processing apparatus is described. However, for example, a process of automatically transferring the wafer 3 such as a single wafer type substrate processing apparatus is performed. Needless to say, the present invention is applicable to any substrate processing apparatus.

(Appendix)
The present invention includes the following embodiments.

  (Supplementary Note 1) A reaction chamber for processing a substrate, a substrate holder on which the substrate is placed and a substrate holder disposed in the reaction chamber during substrate processing, and a state in which the substrate is placed on the substrate holder And a substrate transfer machine for carrying the substrate holder, the substrate transfer machine having an arm for holding the substrate holder, a first light projecting unit for projecting light, and the first light projecting unit. A first fiber sensor having a first light receiving unit that receives light projected from the unit, and the first fiber sensor is configured so that the arm normally holds the substrate holder. A substrate processing apparatus, wherein the substrate holder is disposed between the first light projecting unit and the first light receiving unit.

  (Additional remark 2) The said substrate holder is a substrate processing apparatus of Additional remark 1 whose transmittance | permeability of the light projected from the said 1st light projection part is lower than a board | substrate.

  (Additional remark 3) The said board | substrate transfer machine has several arms arranged in the up-down direction, The said 1st fiber sensor is provided with two or more corresponding to each of these arms, The said 1st light projection The substrate processing apparatus according to appendix 2, wherein either one of the first light receiving unit and the first light receiving unit is disposed so as to be positioned on a side surface of the corresponding substrate holder, and the other is disposed below the substrate holder.

  (Supplementary Note 4) A second fiber sensor further including a second light projecting unit and a second light receiving unit configured to receive light projected from the second light projecting unit, the second fiber The sensor includes a first through-hole formed in the substrate holder between the second light projecting unit and the second light receiving unit when the arm normally holds the substrate holder. The substrate processing apparatus according to appendix 1, wherein the substrate processing apparatus is disposed so as to be positioned.

  (Additional remark 5) The said substrate holder hold | maintains a board | substrate, and the 2nd through-hole was pierced, and the 3rd through-hole was drilled while covering the back surface of a board | substrate supported by this lower board | substrate holder When the lower substrate holder and the upper substrate holder are combined, the second through hole and the third through hole constitute the first through hole. The substrate processing apparatus of appendix 4.

  (Supplementary note 6) The substrate processing apparatus according to supplementary note 4 or supplementary note 5, wherein the first through-hole is filled with a member having a higher transmittance of light projected from the second light projecting unit than the substrate holder. .

  (Supplementary note 7) A third fiber sensor further including a third light projecting unit and a third light receiving unit configured to receive light projected from the third light projecting unit, wherein the substrate holder is a substrate A lower substrate holder, and an upper substrate holder supported by the lower substrate holder and covering the back surface of the substrate, wherein the lower substrate holder has a notch, and the third fiber sensor includes the arm Is arranged so that the notch and the upper substrate holder are positioned between the third light projecting unit and the third light receiving unit when the substrate holder is normally held. 1. A substrate processing apparatus.

  (Additional remark 8) The said upper substrate holder is a substrate processing apparatus of Additional remark 7 in which the protrusion part engaged with the said notch part was formed.

  (Additional remark 9) The said notch part is formed in the peripheral part of the said lower substrate holder, the said protrusion part is formed in the peripheral part of the said upper substrate holder, and the said 3rd light projection part and the said 3rd light-receiving part The substrate processing apparatus according to appendix 8, wherein one of the two is disposed on a side surface of the protruding portion, and the other is disposed below the lower substrate holder.

  (Supplementary note 10) The substrate processing apparatus according to supplementary note 7, wherein the notched portion is a through hole formed in the lower substrate holder, and the protruding portion is a rod-like protrusion that can be fitted into the through hole.

  (Additional remark 11) In order to convey the board | substrate holder with which the board | substrate to be processed was hold | maintained, it light-projects from the 1st light projection part which projects this light, the 1st light projection part which projects light, and this 1st light projection part A first fiber sensor having a first light-receiving unit that receives the received light, and the first fiber sensor has the first fiber sensor when the arm has successfully taken out the substrate holder. A substrate transfer machine, wherein the substrate holder is disposed between a light projecting unit and the first light receiving unit.

  (Additional remark 12) The conveyance process which hold | maintains the board | substrate holder with which the board | substrate to be processed was hold | maintained with the arm of a board | substrate transfer machine, and conveys, The process process which processes a board | substrate in the state hold | maintained at the said substrate holder, And a step of determining whether or not the substrate holder is normally held by the arm in accordance with whether or not the light passing through the substrate holder can be received during the transporting step.

  (Additional remark 13) The conveyance process which hold | maintains and conveys the substrate holder with which the board | substrate to be processed was hold | maintained with the arm of a substrate transfer machine, The process process which processes a board | substrate in the state hold | maintained at the said substrate holder, And a step of determining whether or not the substrate holder is normally held by the arm based on whether or not light passing through the substrate holder can be received during the transporting step.

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 3 Wafer 11 Substrate transfer machine 13 Arm 26 Reaction chamber 58 Wafer holder 59 First fiber sensor 61 Lower wafer holder 62 Upper wafer holder 65 First light projecting part 66 First light receiving part 67 Lower through-hole 68 Upper through-hole 69 Through-hole 71 2nd light projection part 72 2nd light-receiving part 73 2nd fiber sensor 74 Notch part 75 Projecting part 76 3rd light projection part 77 3rd light-receiving part 78 3rd Fiber sensor 79 Through hole 81 Projection

Claims (1)

  A reaction chamber for processing a substrate; a substrate holder for holding a substrate holder on which the substrate is placed; and a substrate holder disposed in the reaction chamber during substrate processing; and the substrate holder in a state where the substrate is placed on the substrate holder. A substrate transfer machine that transports the substrate, and the substrate transfer machine projects an arm that holds the substrate holder, a first light projecting unit that projects light, and a light projecting from the first light projecting unit. A first fiber sensor having a first light receiving portion for receiving the received light, and the first fiber sensor has the first fiber sensor when the arm normally holds the substrate holder. A substrate processing apparatus, wherein the substrate holder is disposed between a light projecting unit and the first light receiving unit.

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