Strained layer device epitaxy on patterned substrates [MODFETs]

The growth of pseudomorphic MODFET structures on a patterned substrate was investigated as a means of increasing the critical layer thickness of strained layers. Prior to growth, semi-insulating GaAs substrates were patterned and etched using chemically assisted ion beam etching to define a series of mesas. Double-doped pseudomorphic MODFET layers were then grown on the substrates by molecular beam epitaxy. To fabricate MODFETs on the resulting non-planar wafer, a new fabrication technique has been developed.<>