INDIUM ARSENIDE - A SEMICONDUCTOR FOR HIGH-SPEED AND ELECTROOPTICAL DEVICES

Indium arsenide is a direct gap semiconductor (0.36 eV at 300 K and 0.40 eV at 77 K) with high electron mobility (greater than 20 000 cm2 V-1 s-1 at 300 K and approximately 60 000 cm2 V-1 s-1 at 77 K). The hole mobilities are in the range 100-400 cm2 V-1 s-1. ItS electro-optical properties are of interest for the IR range out to about 3 mum and to 8 mum in conjunction with In(As,Sb) alloys. Lattice matched heterojunctions can be obtained with alloys such as AlxGa1-x- AsySb1-y. InAs has also been grown on a range of non-lattice-matched semiconductors such as GaSb, InP, GaAs and AlSb, and has exhibited interesting quantum well actions. The field effect transistor (FET) and modulated doped field effect transistor (MODFET) properties are promising but have not been fully developed. The low field for avalanche action (about 10(5) V-1 s-1) presents some device limitations.