4H-SiC PIN diodes for microwave applications

4H-SiC p-i-n diodes were designed, fabricated and characterized with the aim to be used for microwave applications. The best diodes with mesa structure diameters between 80 and 150 /spl mu/m, exhibited a blocking voltage of 1100 V, a 100 mA differential resistance of 1-2 /spl Omega/, a capacitance below 0.5 pF at punchthrough voltage of 100 V and carrier effective lifetime between 15-27 ns. X-band microwave switches based on 4H-SiC p-i-n diodes are demonstrated for the first time. The switches exhibited insertion losses as low as 0.7 dB, isolation up to 25 dB and operation in pulsed high microwave powers of 2.2 k W in isolation mode and 0.4 kW in insertion mode.