Positive-working photoresist elements containing anti-reflective butadienyl dyes which are thermally stable at temperatures of at least 200.degree. C.

Granted: Jan 12, 1988 Filed: Jul 29, 1986

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.