| 摘要 |
PURPOSE:To form a semiconductor thin film selectively only in recess parts described below by forming an irregular part on a semiconductor substrate, and intermittently projecting the constituent elements of the semiconductor thin film to be formed by a molecular-beam epitaxy(MBE) in an atom state to the irregular part. CONSTITUTION:A confining layer 2 comprising P-type Al0.65Ga0.35As having the high resistance is formed on an N-type GaAs substrate 1 by, e.g. the MBE. Thereafter, an irregular part whose interval period is T and depth reaches the surface of the substrate 1 is formed by etching. Then, an MBE device is used, and the raw materials of Ga and As for an N-type GaAs buffer layer 3 to be formed and N-type impurities in atomic states are projected to the irregular part. When the surface is covered by about 50%, the projection is once stopped. The projection is performed intermittently. Then, a layer is not grown on the confining layer 2, but the N-type GaAs buffer layer 3 can be selectively formed only in the recess parts. By the same way, an N-type GaAs active layer 3 and a P-type Al0.3Ga0.7As contact layer 5 can be formed only in the recess parts. It is preferable that the interrupting time of the projection is in the range of 0.1-5 seconds depending on the temperature of the substrate. |
