Member for plasma etching device and method for manufacture thereof

Abstract

A member for a plasma etching device, which comprises a device substrate comprising quartz glass, aluminum, alumite or a combination thereof and, formed on the surface thereof, a coating film of yttrium oxide or YAG having a film thickness of 10 μm or more and a variation in the thickness of 10% or less, and preferably a surface roughness (Ra) of 1 μm or less; and a method for manufacturing the member for a plasma etching device, which comprises a step of plasma-spraying yttrium oxide or YAG to the surface of said device substrate or a step of fusing yttrium oxide or YAG with an oxyhydrogen flame, followed by coating the surface with the fused product, or a step of applying a solution containing yttrium, a yttrium compound or YAG on the above surface, followed by heating to fuse the resultant coating, or a combination of the above steps, thereby forming a coating film of yttrium oxide or YAG having a film thickness 10 μm or more and a variation in the thickness of 10% or less, and preferably a surface roughness (Ra) of 1 μm or less. The member for a plasma etching device is capable of retaining high plasma resistance for a long period of time, is free from the occurrence of the abnormal etching owing to partial change of electric characteristics, and thus can be used for a long time, in particular, even in the treatment of a large semiconductor device of a 12 inch silicon wafer.

1 .- 4 . (canceled) 
     
     
         5 . A method for producing a member for a plasma etching apparatus, comprising forming a coating film of yttrium oxide or YAG having a film thickness of 10 μm or more and a thickness variance of 15% or less formed on a surface of a member for a plasma etching apparatus comprising quartz glass, aluminum, alumite or a combination thereof by any one of the following methods: a method of plasma-spraying yttrium oxide or YAG, a method of fusing yttrium oxide or YAG powder by an oxyhydrogen flame and, then, performing coating, a method or applying a solution in which yttrium, a yttrium compound or YAG is dissolved and, then, performing heat-fusing, and a combination thereof. 
     
     
         6 . The method for producing the member for the plasma etching apparatus according to  claim 5 , wherein a solution in which yttrium, a yttrium compound or YAG is dissolved is applied on a surface of a member for a plasma etching apparatus comprising quartz glass, aluminum, alumite or a combination thereof and, then, heat-fused to form a coating film of yttrium oxide or YAG and, thereafter, further, yttrium oxide or YAG is plasma-sprayed. 
     
     
         7 . The method for producing the member for the plasma etching apparatus according to  claims 5  or  6 , wherein a ridge portion of the member is subjected to rounding machining so as to have a size or R 0.5 mm or more and, then, a coating film of yttrium oxide or YAG is formed. 
     
     
         8 . The method for producing the member for the plasma etching apparatus according to  claims 5  or  6 , wherein a surface roughness Ra of the coating Film of yttrium oxide or YAG is allowed to be 1 μm or less. 
     
     
         9 . The method for producing the member for the plasma etching apparatus according to  claims 5  or  6 , wherein the member for the plasma etching apparatus comprises quartz glass. 
     
     
         10 . The method for producing the member for the plasma etching apparatus according to  claim 9 , wherein after the surface is subjected to a frost treatment, a coating film of yttrium oxide or YAG is formed. 
     
     
         11 . The method for producing the member for the plasma etching apparatus according to  claim 10 , wherein the frost treatment is a surface treatment using a chemical solution. 
     
     
         12 . The method for producing the member for the plasma etching apparatus according to  claim 9 , wherein a coating film of yttrium oxide or YAG is formed on a surface of a quartz glass member in which 1 to 10% by weight of yttrium oxide or YAG is previously contained.