Fine-line circuit fabrication and photoresist application therefor

摘要

A method is disclosed for the production of thick and smooth layers of photoresist on the order of 2-15 microns thick. The substrate is flooded with resist as in the standard spin resist method, but instead of following the flooding step with spinning as usual, the second step is to provide a drying time for the flooded resist. Then at the end of the measured drying time, the resist is spun as usual. This can be used to produce fine line closely spaced circuitry in which the thickness of the lines in proportion to their width, or their aspect ratio, is large. Aspect ratios greater than 0.4 and as high as 1.5 are contemplated by the invention.