New aspects in elaboration of microwave diodes based on A3B5 compounds

Development of solid-state electronics for millimeter and sub-millimeter wavelength range directly connected with solution of two physico-technological problems: manufacturing highly reliable, thermo- and radiation-resistant ohmic and Schottky contacts to submicrometer layers of A₃B₅ based semiconductors; growth of perfect sub-micrometer homo- and hetero-epitaxial films based on A₃B₅ semiconductors. In this communication we present our approach to solution of these problems. First, high quality ohmic and Schottky contacts to IMPATT and Gunn diodes have been fabricated using amorphous alloys of nitrides and borides of the refractory metals. Second, we have developed method for obtaining epitaxial structures and microwave devices based on them with low level of internal mechanical strains The main idea consists in using of so called "porous" substrates, i.e., substrates containing porous layer on the surface. Diode structures with Schottky barrier as well as Gunn diodes grown on GaAs and InP "porous" substrates have been fabricated and studied. Microwave generation has been obtained in frequency range of 120-150 GHz in pulse regime.