| 摘要 |
PURPOSE:To take out a current at a high speed, when a high impurity concentration thin film is formed in the vicinity of an interface between a spacer layer and an electron supplying layer on an active layer, by increasing the electron concentration of a two-dimensional gas layer formed in the active layer. CONSTITUTION:A high-purity, I-type AlxGa1-xAs spacer layer 4 is grown. Thereafter, shutters for Al and Ga molecular beam cells are closed, and only shutters for Si and As molecular beam cells are opened. Then, high-concentration Si doping is performed. Thereafter, the shutters for the Si molecular beam cell is closed, and the shutter for the Al molecular beam cell and the shutter for the Ga molecular cell are opened again, and an N-type AlxGa1-xAs electron supplying device 5 is grown. Thus the electron concentration in a two-dimensional electron gas layer formed in an active layer becomes higher than the conventional device. As a result, transfer conductance becomes high, and a large current can be taken out. |
