Graft polymerized sio.sub.2 lithographic masks

Abstract

This invention provides a process, and delineates typical materials to be used in that process, which enables the use of a precision radiation source to produce a microcircuit resist image accurate to a few micrometers or even fractions of a micrometer. In addition, the process of the invention provides for the dry development of this image, thus insuring the ability to create a finished resist structure exhibiting the same accuracy in dimensions. Specifically, the invention provides a process in which a positive or negative resist polymer is irradiated under low pressure using a precision radiation source such as an electron beam, masked ion beam, or focused ion beam to generate organic free radicals. After irradiation, the reactive resist polymer is exposed to oxygen or air to create peroxides or hydroperoxides. The peroxides or hydroperoxides are later thermally decomposed to generate organic free radicals which can be reacted with a silicon-containing organic molecule which contains at least one vinyl or other functional group capable of reacting with the organic free radical. The resulting copolymer resist then includes a latent image containing silicon, which can be dry developed using plasma or reactive ion etching techniques. In another embodiment of this invention, an intermediary non-silicon-containing organic molecule is grafted to the active sites on the resist polymer. The organic molecule is then reacted with a silicon-containing compound, so that it becomes a grafting intermediary between the initial polymeric resist and the silicon-containing compound.