The present invention relates to a treating apparatus for treating a to-be-treated substrate such as a glass substrate mounted on a mount disposed in a vacuum vessel while controlling the temperature of the to-be-treated substrate into a predetermined temperature, and particularly relates to a configuration of the substrate mount of the treating apparatus.
In a treating apparatus for performing plasma treatment or the like upon the surface of a to-be-treated substrate (hereinafter also referred to as “substrate” simply), a substrate mount having a function as an electrostatic chuck for mounting and fixing the substrate is used. In the substrate mount, a large number of narrow holes are opened in the substrate mounting area thereof, or processing such as grooving or dimpling is performed, so that various kinds of gases for surface treatment can be supplied to the whole area of the mounted substrate. JP-A-2002-222799 discloses a plasma treatment apparatus in which a corrosion resistant film is formed around a substrate mount made of a carbon substrate so as to prevent corrosion with oxygen gas. JP-A-6-216224 discloses a substrate mount with an electrostatic chuck in which a ceramic plate is brazed with a metal substrate. JP-A-5-152425 discloses a substrate mount in which an electrostatic adsorption electrode is buried in a heater block where a heater (heating elements) is planted. JP-A-6-279974 discloses a substrate mount in which a conductor portion exposed from a ceramic substrate is coated with an insulating spray deposit.
In the aforementioned background art, however, it is difficult to diffuse gas uniformly over the whole area of the to-be-treated substrate mounted on the substrate mount. In addition, there occurs a variation of heat transfer in the contact surface between the substrate mount and the to-be-treated substrate. It is therefore difficult to perform substrate treatment with high quality.
An object of the present invention is to provide a treating apparatus in which gas can be diffused uniformly over the whole area of a to-be-mounted substrate mounted on a substrate mount, and the whole area of the surface of the substrate can be treated uniformly.
Typical configurations of the present invention to attain the foregoing object will be described below. That is, according to the invention, a treating apparatus for performing various surface treatments upon a to-be-treated substrate mounted on a mount disposed in a vacuum vessel while controlling the temperature of the to-be-treated substrate into a predetermined temperature is designed as:
(1) the mount is made of a porous substrate having communicating pores; and
gas supplied to the communicating pores on the opposite side of the porous substrate to the to-be-treated substrate is spouted to a surface of the to-be-treated substrate facing the mount.
(2) A gas supply means is provided for supplying gas to the communicating pores from the opposite side of the porous substrate to the to-be-treated substrate;
a surface portion of the porous substrate facing the to-be-treated substrate is coated with a gas-permeable insulating film while the other surface portion of the porous substrate is coated with a non-gas-permeable insulating film;
an electrostatically chucking electrode is buried inside the gas-permeable insulating film in the surface portion of the porous substrate on the surface side where the to-be-treated substrate is mounted;
an electrostatically chucking DC power supply is provided for applying electrostatic potential to the electrostatically chucking electrode; and
the gas supplied to the communicating pores of the porous substrate from the opposite side to the to-be-treated substrate is spouted uniformly through the communicating pores of the porous substrate to the surface side where the to-be-treated substrate is mounted.
(3) An electrostatically chucking electrode is buried inside the surface portion of the porous substrate on the surface side where the to-be-treated substrate is mounted, in the state where the peripheral surface of the electrostatically chucking electrode is coated with an electrically insulating coating;
a gas supply means is provided for supplying gas to the communicating pores of the porous substrate, and an electrostatically chucking DC power supply is provided for applying electrostatic potential to the electrostatically chucking electrode;
a surface portion of the porous substrate except a surface portion facing the to-be-treated substrate is peripherally coated with a non-gas-permeable insulating film; and
the gas supplied to the communicating pores of the porous substrate from the opposite side to the to-be-treated substrate is spouted uniformly through the communicating pores of the porous substrate to the surface side where the to-be-treated substrate is mounted.
(4) The gas supply means for supplying gas to the porous substrate includes:
a gas inlet for introducing the gas from the opposite side of the mount to the to-be-treated substrate;
a cylindrical gas filled portion extending from the gas inlet to a central portion of the porous substrate;
a gap portion formed into a sheet-like shape so as to extend broadly inside the porous substrate from one end of the gas filled portion; and
a large number of worked grooves provided at predetermined intervals or a large number of dimples provided independently of one another, in an inner wall surface of the porous substrate on the to-be-treated substrate side of the gap portion.
(5) Heating elements are planted in the porous substrate so as to be joined integrally therewith, and an AC power supply is provided for supplying power to the heating elements from the opposite side of the mount to the to-be-treated substrate.
(6) A surface portion of the porous substrate facing the to-be-treated substrate is coated with a gas-permeable insulating film while the other surface portion of the porous substrate is coated with a non-gas-permeable insulating film;
an AC power supply is provided for supplying power to the heating elements from the opposite side of the mount to the to-be-treated substrate, while a gas supply means is provided for supplying gas to the communicating pores of the porous substrate; and
the gas supply means includes a gas inlet for introducing the gas from the opposite side of the mount to the to-be-treated substrate, a cylindrical gas filled portion extending from the gas inlet to a central portion of the porous substrate, a gap portion formed into a sheet-like shape so as to extend broadly inside the porous substrate from one end of the gas filled portion, and a large number of worked grooves provided at predetermined intervals or a large number of dimples provided independently of one another, in an inner wall surface of the porous substrate on the to-be-treated substrate side of the gap portion.
As for the material to the porous substrate, carbon or corrosion-resistant metals may be provided. Several metals, e.g., nickel (Ni), copper (Cu), or those alloys may be useful.
According to the present invention, it is possible to obtain the following excellent effects. That is:
In a treating apparatus for treating a to-be-treated substrate mounted on amount in a vacuum vessel while controlling the temperature of the to-be-treated substrate into a predetermined temperature, gas is supplied uniformly to the back surface of the substrate through communicating pores of a porous substrate of the mount. It is therefore possible to control uniformly the temperature of the to-be-treated substrate over the whole area of the substrate surface.
The porous substrate of the mount is stable at high temperature and excellent in heat conductivity. Accordingly, the porous substrate is heated easily by various treatment gases (e.g. heat conductive gas) introduced through the communicating pores of the porous substrate. In addition, due to the heating elements such as sheath heaters planted inside the mount, the porous substrate can be heated easily in a short time. As a result, the temperature of the mount can be controlled accurately and rapidly.
Further, the peripheral surface of the porous substrate of the mount except the surface facing the to-be-treated substrate is coated with a non-gas-permeable insulating film. Accordingly, heat conductive gas is intensively hit against only the back surface (the side facing the mount) of the to-be-treated substrate. Thus, the efficiency in heating the to-be-treated substrate is excellent, and consumption of the porous substrate caused by oxidation is prevented. When inert gas is used as the heat conductive gas, consumption of the mount of the porous substrate caused by oxidation can be prevented perfectly. Thus, excellent durability can be obtained.
Preferred embodiments of the present invention will be described below in detail with reference to the drawings.
These embodiments are described in the case of the material of porous substrate to be carbon. With corrosion-resistant metals may be provided in the same way as in the case of carbon.
The treating apparatus according to the first embodiment treats the to-be-treated substrate (substrate) 12 mounted on the substrate mount (hereinafter also referred to as “mount” simply) disposed in the vacuum vessel 2 (only a part of the wall of the vacuum vessel is shown in
Further, a gas supply means is provided for supplying the gas 9 (e.g. He gas) to the porous carbon substrate 4. The electrostatically chucking DC power supply 11 is provided for applying electrostatic potential to the electrostatically chucking electrode 5 buried in an upper portion of the mount 1. The porous carbon substrate 4 is peripherally coated with the heat-resistant insulating film 8 of ceramics or the like.
As the gas supply means for supplying the gas 9 to the porous carbon substrate 4, the gas inlet 13 and the cylindrical gas filled portion 14 are disposed. The gas inlet 13 penetrates the bottom of the heater base 3 disposed inside the bottom of the vacuum vessel 2 in a lower portion of the mount 1. The gas filled portion 14 extends from the gas inlet 13 to a central portion of the porous carbon substrate 4. The gap portion 15 is formed into a sheet-like shape extending broadly inside the porous carbon substrate 4 from the center top of the gas filled portion 14. Further, the porous carbon substrate bonding portions 6 on the top of the gap portion 15 are provided to sink at the predetermined intervals 7′. Thus, the porous carbon substrate 4 to be bonded is grooved to form the grooved portions 7. A large number of dimpled concave holes (not shown) may be provided independently of one another instead of the grooved portions.
The lead wire 17 provided to extend from the central portion of the electrostatically chucking electrode 5 toward the illustrated bottom (opposite to the side where the substrate should be mounted) is connected to the external DC power supply 11 through the gas inlet 13.
As shown in the enlarged view of
The mount 1 shown in
Further, the peripheral surface of the porous carbon substrate 4 except the surface facing the to-be-treated substrate 12 is coated with a non-permeable insulating film 8. Thus, gas 9 supplied from below to the communicating pores of the porous carbon substrate 4 is transmitted through the communicating pores of the porous carbon substrate 4 and spouted uniformly to the back surface of the substrate 12.
As shown in
This treating apparatus treats a to-be-treated substrate 12 mounted on a mount 1 disposed in a vacuum vessel 2 illustrated by its wall surface, while controlling the temperature of the to-be-treated substrate 12 into a predetermined temperature. The treating apparatus is configured as follows. That is, after the heating elements 21 (sheath heater) are planted between two upper and lower split pieces of the porous carbon substrate 25, the two pieces of the porous carbon substrate are bonded integrally with each other with the gap 22 being set therebetween. The porous carbon substrate 25 integrated thus serves as a carbon heater substrate forming the substrate mount 1. Of the carbon heater substrate forming the substrate mount 1, the surface facing the to-be-treated substrate 12 is coated with a gas-permeable insulating film 20′, and the other peripheral surface thereof is coated with the non-gas-permeable insulating film 20. This insulating film may be, for example, a heat resistant ceramic spray deposit.
Further, the heater power supply 23 is provided for supplying power to the heating elements 21 from the bottom of the vacuum vessel 2. A pair of heater cords 24 are disposed to extend from the heater power supply 23 through cord insertion holes 28 to the central portion of the porous carbon substrate 25 forming the carbon heater substrate and further supply power to the heating elements 21 disposed at predetermined intervals around the center with respect to the thickness of the carbon heater substrate. The heating elements 21 are fixedly retained in the bonding portion 22 between the two pieces of the porous carbon substrate 25 forming the carbon heater substrate.
A cylindrical gas filled portion 14 is disposed as a gas supply means for supplying the inert gas 26 toward the carbon heater substrate formed out of the porous carbon substrate 25. The gas filled portion 14 extends to the central portion of the carbon heater substrate from an inert gas inlet 13 penetrating the bottom of a heater base 3 disposed inside the bottom of the vacuum vessel 2 in a lower portion of the mount 1. A gap 15 is formed into a sheet-like shape extending broadly inside the carbon heater substrate from the center top of the filled portion 14. Therefore, an inert gas atmosphere 27 filled with the inert gas is formed. Further, in the upper surface of the gap 15, the heating elements 21 are planted at predetermined intervals in the porous carbon substrate 25 forming the carbon heater substrate.
According to the second embodiment described above, there is no fear that oxidizing gas touches the carbon heater substrate formed out of the porous carbon substrate 25. In addition, inert gas is introduced into the inside of the porous carbon substrate 25. Thus, consumption of the porous carbon substrate caused by oxidation can be suppressed. Further, the inert gas is charged into the gas between the porous carbon substrate and each heating element. Thus, the heat transfer efficiency is improved.
Also according to the third embodiment described above, gas is supplied uniformly to the back surface of the to-be-treated substrate through the communicating pores of the porous carbon substrate of the mount in the same manner as in the first embodiment. Accordingly, the temperature of the to-be-treated substrate can be controlled uniformly all over the substrate.
Number | Date | Country | Kind |
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2004-348916 | Dec 2004 | JP | national |
2005-301722 | Oct 2005 | JP | national |