High electron mobility transistor with GaN/Al.sub.x Ga.sub.1-x N heterojunctions

摘要

A high electron mobility transistor is disclosed, which takes advantage of the increased mobility due to a two dimensional electron gas occurring in GaN/Al.sub.x Ga.sub.1-x N heterojunctions. These structures are deposited on basal plane sapphire using low pressure metalorganic chemical vapor deposition. The electron mobility of the heterojunction is aproximately 620 cm.sup.2 per volt second at room temperature as compared to 56 cm.sup.2 per volt second at 180° K. and decreased to 19 cm. sup. 2 per volt second at 77° K. The mobility for the heterostructure, however, increased to a value of 1,600 cm.sup.2 per volt second at 77° K. and saturated at 4° K.