| 摘要 |
PURPOSE:To obtain a field effect transistor, whose switching speed is very high, by forming a so-called heterojunction, wherein the width of the forbidden band of an n-layer is broader than the width of the forbidden band of a p-layer, in a p-n junction. CONSTITUTION:n-layers 200, 210 and 220 of an electrostatic induction transistor 10 are formed by Si. A p<+> layer 300 is formed by a mixed crystal of SixGe1-x (0<=x<1). The n<-> Si layer 210 and the p<+> SixGe1-x layer 300 form a heterojunction. In this constitution, electrons 40 are injected to the p<+> layer 300. The injection of holes 50 is blocked by an energy barrier, which is caused by the difference in widths of the forbidden bands of the Si and the SixGe1-x. Therefore, stored carriers in the n<-> layer 210 becomes extremely less. Thus the switching speed of BSIT is improved to a large extent. |
