Indium Phosphide for Microwave Gunn Devices.

One-micron-thick films of InP were epitaxially deposited onto single-crystal InP substrates at about 400 deg C by the planar reactive deposition technique. Scanning electron microscope measurements show that smooth surfaces are obtained on (100) substrates, and shingled surfaces are obtained on (III) substrates. Mass spectrographic analysis indicates that the purity of these films is about 10 parts per million atomic. Electrical evaluation of these films deposited on semi-insulating substrates shows that at room temperature the films are n-type with electron concentrations as low as 10 to the 16th power/cu cm and mobilities as high as 1350 sq cm/V sec. (Author)