An indium phosphide diffused junction field effect transistor

A junction field effect transistor (JFET) that meets the numerical requirements of an electrooptic receiver sensitive to 1.3 and 1.55 mu m optical radiation is reported. It was made by diffusing zinc into an epitaxial channel of indium phosphide. Low-frequency characterization showed that it has a transconductance of 240 mS/mm, a capacitance of 3.25 pF/mm, a gate-to-source leakage current of 10 nA at a bias of -4 V, and a one week stability of 3 mA out of 145 mA under the application of constant bias. The calculated unity current gain frequency is 12 GHz. The device should be suitable for wideband DC coupled integrated circuits made with InP-based materials.<>