Selectively-doped Al0.48In0.52As/Ga0.47In0.53As heterostructure field effect transistor

Selectively-doped depletion-mode FET's which show full pinch-off at 295 K with transconductance in excess of 90 mS/mm and contact resistance less than 0.4 Ω-mm have been fabricated. The device properties reported represent a significant improvement over previously published work on an equivalent structure, because of improvements in growth technique and modifications in the device structure. Analysis of our measurement at room temperature suggests that the two-dimensional electron gas at the hetero-interface is not the dominant contributor to the total device current.