Planar GaAs integrated circuits fabricated by ion implantation

A unique fabrication technology is described for planar ion implanted GaAs integrated circuits. The planar processing techniques presented are compatible with any GaAs IC logic approach and promise fabrication yields compatible with the long-term goals of LSI circuit complexities. Planar depletion-mode GaAs ICs have been fabricated using multiple localized implantations directly into semi-insulating GaAs substrates. Fabrication techniques for the fine-line circuit lithography include the utilization of a 4× projection mask aligner. Performance of planar GaAs NOR gates exhibit excellent switching characteristics and low power levels.