Double heterojunction GaInAs devices by MBE

MESFETs with Ga0.47In0.53As active channel grown by MBE on InP substrates were successfully fabricated Thin layers of MBE grown Al0.48In0.52As separated both the single crystal aluminum gate from the active channel and the active channel from the semi-insulating InP substrate so raising the Schottky barrier height and confining the electrons to the channel. The MESFETs with 0.6 µm long gates and gate-to-source separations of 0.8 µm exhibited an average gmof 135 mS mm^-1of gate width for Vds= 2V and Vg= 0V. An integrated photoreceiver comprising a dual gate DH GaInAs MESFET and two notch-type photoconductive detectors in series has been fabricated and shows potential for high speed operation.