Method of making semiconductor device with passivated rectifying

Abstract

A device and method for forming the device formed of semiconductor material provides metallization for the circuit and passivation of a rectifying junction in but a single photolithographic etching step. The device may be formed of silicon, gallium arsenide or silicon-on-sapphire. The rectifying junctions may be formed of material of opposite conductivity types or may be of the Schottky barrier type in which metal in contact with a semiconductor material forms a rectifying junction. Metal is initially deposited at suitable temperatures over all the surface of a body of material having rectifying junctions. The metal over the junctions is removed by a photolithographic resist process leaving the rectifying junctions clear of metal. The metal or metals are then heat treated at high temperatures. The rectifying junction is passivated by amorphization and hydrogenation at relatively low temperatures to provide the device with a passivated junction of graded crystallinity. The formation of two-rectifying junction mesa-type transistor is described using only two photolithographic etching steps. A semiconductor device made by these processes are extremely stable.