Electron beam masking method
Abstract
Abstract A METHOD OF MASKING A SUBSTRATE BY COATING THE SUBSTRATE WITH A DIENE-DERIVED LINEAR POLYMER HAVING AT LEAST ONE ACTIVE HYDROGEN FOR EVERY TEN REPEATING UNITS, INSOLUBILIZING THE POLYMER BY EXPOSING IT TO AN ELECTRON BEAM, AND REMOVING THE UNEXPOSED PORTIONS OF THE POLYMER COATING. SPECIFICALLY, A SUBSTRATE OF SIO2 ON A SILICON CHIP MAY BE MASKED FROM AN HF ETCHANT BY APPLYING BENZENE SOLUTION OF 1,2-SYNDIOTACTIC POLYBUTADIENE OR, A RANDOM COPOLYMER OF STYRENE AND BUTADIENE TO THE SUBSTRATE. THE SOLUTION IS SPUN TO DRYNESS AND THE RESULTING POLYMERIC LAYER IS EXPOSED TO AN ELECTRON BEAM WHICH TRACES DESIRED PATTERNS ON THE POLYMERIC LAYER. THE CHIP IS THEN WASHED IN BENZENE AND ETCHED IN HF.
Inventors
- 👤 L Scala
- 👤 D Ciliberti
Bibliographic Details
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