CHARACTERISTICS OF DELTA-DOPED FETS IN GAAS

Experimental data is presented on several batches of delta-doped field effect transistors grown by molecular beam epitaxy in GaAs. The expected linear transfer characteristics were observed and values of extrinsic transconductance comparable with the best values reported elsewhere were obtained. Excellent consistency was obtained between devices fabricated on the same layer, and between batches grown on different layers. Depletion and enhancement characteristics are shown. Reasonable agreement was obtained between the measured characteristics and a simple theory based on a piecewise linear approximation to the velocity-field curve.