Microlithography Resists Containing Poly(1,1-dimethylsilazane)

Poly(1,1-dimethylsilazane), PDMZ, mixes well with most of resist materials, cresol-formaldehyde novolak resins, poly(hydroxystyrene), chlorinated poly(1,1-methyistyrene) and others. The mixed resist solution provides uniform films when it is spin-coated on a substrate like a silicon wafer. Although it may form a C-T complex with diazonaphtho-quinone photosensitizers, the mixed photoresist keeps its photosensitivity for several weeks. Resist with PDMZ can be used as an imaging layer in RIE bilayer resist systems. Its silicon content is enriched in resist surface layers. After oxygen reactive ion etching, resist surfaces were covered with silicon oxide layers.