Papers by Author: L.P. Romanov

Abstract: 4H-SiC p-i-n diodes were designed, fabricated and characterized for use in microwave applications. The diodes exhibited a blocking voltage of 1100 V, a 100 mA differential resistance of 1-3 &, a capacitance below 0.5 pF at a punchthrough voltage of 100 V and a carrier effective lifetime between 15-27 ns. Single 4H-SiC p-i-n diode switches, operating in X-band, exhibited insertion loss 0.7 dB, isolation up to 25 dB and were able to handle microwave power up to 2.2 kW in pulsed mode of operation. The switching speed of the switches has not exceeded 20 ns.

Abstract: 4H-SiC p-i-n diodes were fabricated on epitaxial layers grown by Sublimation Epitaxy in Vacuum (SEV) and were evaluated for microwave power switching applications. Full electrical characterization (C-V, DC I-Vs, reverse recovery characteristics, low and high power microwave testing) has been performed. The results showed that SEV-grown SiC material is suitable for bipolar device fabrication. A doping higher than 1019 cm-3 for the p-type contact layer and lower than 1016 cm-3 for the n-type base layer is necessary to demonstrate microwave p-i-n diodes with similar performance as the ones fabricated on commercially available CVD-grown material.