| 摘要 |
PURPOSE:To obtain an FET which has preferable characteristics by employing an InP substrate of planar azimuth (111)A and (111)B, thereby reducing the level density of the boundary from an insulating film. CONSTITUTION:The level density of a boundary between the (111)A and (111)B of an InP substrate and an insulating film is less than that of the other plane azimuth (110), (100). Accordingly, when an FET is formed of an Si3N4 film 3 on the InP substrate 1 of this planar azimuth as prescribed, leakage current is reduced, and switching characteristics can be improved. Even when an InGaAs film 12 or further an InP film 13 is epitaxially grown on the InP film 11 of this planar azimuth, the planar azimuth of the grown layer becomes (111)A or (111)B, thereby obtaining preferable characteristics of the element. |
