| 摘要 |
PURPOSE:To obtain a semiconductor switching device, wherein large current can be flowed, by a method wherein the p-n junction consisting of the p type layer and the n<+> type layer is formed into a so-called heterojunction having the n<+> type layer with the forbidden band width smaller than that of the p type layer or is formed into a Schottky junction using the Schottky metal layer instead of the n<+> type layer. CONSTITUTION:An n<+> type layer 50 having the forbidden band width smaller than that of the p<+> type layer or a Schottky metal layer 50 is used instead of the n<+> type layer. As a result, the heterojunction or the Schottky junction is formed on the interface between the n<+> type layer 50 or the Schottky metal layer 50 ad the p type layer. When current is in a turn-ON state, an n<+> type layer, which is an inversion layer, is formed in the p type layer at a point A, which is the heterojunction, under an insulating film 30 and electrons flow to the semiconductor having the larger forbidden band width from the semiconductor having the smaller forbidden band width. These electrons urge positive holes being injected from the p<+> type layer. As a result, the positive holes are injected in the n<+> type layer at a point B. As DELTAEc exists between the n<+> type layer and the p type layer, the electrons injected in the p<+> type layer become hard to being injected in the p type layer. As a result, the semiconductor switching device ceases to latch-up and can fulfill a large-current operation. |
