Novel Chrome Mask Manufacture Without an Etching Step
Original Publication Date: 1985-Jan-01
Included in the Prior Art Database: 2005-Feb-18
Chrome or other transition metal optical projection masks can be produced without the use of an etch step, thus eliminating etch bias considerations. The process flow of the mask manufacture would be as follows: 1. Coat mid UV (ultraviolet) or visible light sensitive photoresist on a quartz substrate (not coated with chrome). 2. Expose and develop the photoresist in a standard fashion. 3. Deposit chrome or other transition metal only in areas of open photoresist. 4. Strip off photoresist. Steps 1, 2 and 4 do not differ greatly from standard processing with the exception of the printing step during which slightly greater contrast could be achieved due to the non-reflecting target. The majority of this article deals with step number three.