Gold-compensated high resistivity silicon as low-loss microwave substrate

Deep level doping compensation concept using elemental gold is utilised to create effectively high resistivity silicon substrates for the use in GHz range. Bias-dependent substrate losses associated with parasitic surface conduction is fully suppressed, indicated by the constant attenuation loss of 0.19 dB/mm at 40 GHz for the coplanar waveguides fabricated on the substrates. In addition to that, the incorporation of slow-cooling treatment in the annealing procedure proves that further increase in substrate resistivity can be achieved for Czochralski-grown silicon substrates, rising up its potential as one of the alternative substrates for radio-frequency monolithic microwave integrated circuits applications.