Substrate fed logic - An improved form of injection logic

A novel form of integrated injection logic is described which has significant advantages over its conventional counterpart in packing density and power-delay product. The structure is formed from two epitaxial layers on a heavily doped p type substrate. The p type epitaxial layer, which forms the base of the npn transistor, is lightly doped, allowing the fabrication of Schottky contacts. This gives rise to an extremely powerful multi-input, multi-output logic element on a single base land. The fundamental SFL structure has been successfully demonstrated. Gates and a ring oscillator have been operated and a reduction in power-delay product has been shown. A viable technology for Schottky Barrier Diodes has been demonstrated and an optimised structure has been designed.