Process For Cleaning Shield Surfaces In Deposition Systems

Abstract

A process for cleaning and restoring deposition shield surfaces which results in a cleaned shield having a surface roughness of between about 200 microinches and about 500 microinches and a particle surface density of less than about 0.1 particles/mm 2 of particles between about 1 micron and about 5 microns in size and no particles less than about 1 micron in size and method for use thereof is disclosed.

What is claimed is: 
     
         1 . A deposition shield, comprising:
 a shield having a surface roughness of between about 200 microinches and about 500 microinches and a surface particle density of less than about 0.1 particles/mm 2  of particles between about 1 micron and about 5 microns in size and no particles below about 1 micron in size, said shield being fabricated by:   roughening the surface of a stainless steel shield by grit blasting the shield with fresh grit material;   loosening particles embedded in the roughened surface by etching the surface with a chemical etch solution; and   removing loosened particles from the roughened surface by at least one of a high pressure rinse and ultrasonication, to provide the shield with a surface roughness of between about 200 microinches and about 500 microinches and a surface particle density of less than about 0.1 particles/mm 2  of particles between about 1 micron and about 5 microns in size and no particles below about 1 micron in size.   
     
     
         2 . An EUVL mask blank comprising:
 a layer deposited in a deposition chamber having a shield with a surface roughness of between about 200 microinches and about 500 microinches and a surface particle density of less than about 0.1 particles/mm 2  of particles between about 1 micron and about 5 microns in size and no particles below about 1 micron in size, said shield being fabricated by:   roughening the surface of a stainless steel shield by grit blasting the shield with fresh grit material;   loosening particles embedded in the roughened surface by etching the surface with a chemical etch solution; and   removing loosened particles from the roughened surface by at least one of a high pressure rinse and ultrasonication, to provide the shield with a surface roughness of between about 200 microinches and about 500 microinches and a surface particle density of less than about 0.1 particles/mm 2  of particles between about 1 micron and about 5 microns in size and no particles below about 1 micron in size.