| 摘要 |
PURPOSE:To obtain the titled FET, the electric resistance of a light-receiving section layer and source-drain thereof is lowered and which can be operated at high speed, by selectively forming a large number of irregular shapes to the interface between a semiconductor substrate and a low concentration layer. CONSTITUTION:Grooves 9 are dug selectively to an InP substrate under a light- receiving section 10, a source 11 and a drain 13 through etching, and the thickness of an N layer under the light-receiving section 10 and the layers of the source 11 and the drain 13 is made effectively thicker than that of conventional elements. The grooves 9 are formed in such a manner that resists 14 are shaped to the InP substrate 7 in an orientation such as a (10, 0) orientation to a striped form in the direction such as the (0, 1, -1) direction and the substrate is etched by using CH3OH. Accordingly, the resistance of a low concentration layer can be lowered effectively, and operation at high speed is enabled. |
