Internal member for plasma-treating vessel and method of producing the same

Abstract

It is to propose an internal member for a plasma treating vessel having excellent resistances to chemical corrosion and plasma erosion under an environment containing a halogen gas and an advantageous method of producing the same, which is a member formed by covering a surface of a substrate with a multilayer composite layer consisting of a metal coating formed as an undercoat, Al 2 O 3 film formed on the undercoat as a middle layer and Y 2 O 3 sprayed coating formed on the middle layer as a top coat.

1 . An internal member for a plasma-treating vessel comprising a substrate and a high purity Y 2 O 3  plasma sprayed coating having a purity of not less than 95 mass % covered on a surface thereof.  
     
     
         2 . An internal member for a plasma-treating vessel according to  claim 1 , wherein the plasma sprayed coating is formed through a plasma spraying process under an atmosphere containing substantially no oxygen.  
     
     
         3 . An internal member for a plasma-treating vessel according to  claim 2 , wherein the atmosphere containing substantially no oxygen is an Ar gas.  
     
     
         4 . An internal member for a plasma-treating vessel according to  claim 1 , wherein the substrate is an internal part for a plasma-treating vessel.  
     
     
         5 . An internal member for a plasma-treating vessel according to  claim 4 , wherein the part is required to have strong resistances to damages caused by a chemical corrosion and a plasma erosion in an atmosphere containing halogen gas under an environment of using plasma.  
     
     
         6 . An internal member for a plasma-treating vessel according to  claim 5 , wherein the atmosphere containing halogen gas under an environment of using plasma includes one or more in atomic material such as F, Cl, Br or I dissociated from a halogen compound.  
     
     
         7 . An internal member for a plasma-treating vessel according to  claim 5 , wherein the atmosphere containing halogen gas under an environment of using plasma includes one or more in atomic material such as F, Cl Br or I dissociated from a halogen compound and one or more in a finely divided solid of SiO 2 , Si 3 N 4 , Si or W exist together.  
     
     
         8 . An internal member for a plasma-treating vessel according to  claim 1 , wherein the Y 2 O 3  of the sprayed coating has a purity of not less than 98 mass %.  
     
     
         9 . An internal member for a plasma-treating vessel according to  claim 1 , wherein Y 2 O 3  of the sprayed coating has a purity of not less than 99.5 mass %.  
     
     
         10 . An internal member for a plasma-treating vessel according to  claim 1 , wherein Y 2 O 3  of the sprayed coating has a purity of not less than 99.8 mass %.