High-breakdown-voltage Ga/sub 0.51/In/sub 0.49/P channel MESFET's grown by GSMBE

The first Ga/sub 0.51/In/sub 0.49/P channel MESFETs grown on a (100) GaAs substrate by GSMBE have been fabricated. A high gate-to-drain breakdown voltage of 42 V with a high maximum current density (320 mA/mm) was achieved. This result demonstrates that high-breakdown voltage could be attained by using Ga/sub 0.51/In/sub 0.49/P as the channel material. We also measured a high-maximum oscillation frequency (f
_max
) of 30 GHz for a 1.5 μm gate-length device. This value is quite high compared with other high-breakdown-voltage GaAs MESFET's or MISFET's with the same gate length.