A novel high speed electron resist

The combination of a gel-free silver halide deposit with a chalcogenide glass layer is being investigated for its potential as an ultra high speed electron-sensitive resist. A vacuum evaporated silver halide layer which, in 200 to 300 nm thickness, is capable of photographic speeds exceeding 10^-10coulombs/cm²for 2 to 20 Kev electrons (or ions), is employed as the source of silver for photodoping into the chalcogenide. The optimum thickness of silver halide necessary to confer etch resistance to the thicker substratum of amorphous chalcogenide is determined from doping experiments with a pure silver/chalcogenide system and from SEM structural studies of silver halide films of diminishing thickness on various substrates. The system also possesses sensitivity to soft X-rays and ultraviolet light and can be made to operate in either a negative or positive resist mode with equal sensitivity to the exposing radiation.