SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

• Main Authors: MATSUDA SHIGENOBU, TORII KATSUYUKI
• Format: Patent
• Language: English; Japanese
• Published: 12.11.2015
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To achieve both a high-speed operation and improvement in withstanding voltage.SOLUTION: In a structure in Fig. 1, an oxide film 26 is formed to be uniformly thin on a lateral face where a gate electrode 27 is formed and to be thick at a bottom face center side of a groove 24. In this structure, the gate electrode 27 is not formed at the bottom face side of the groove 24, and is divided into both sides, and a bottom face electrode 28 is made to have the same potential as an emitter electrode 30. Thereby, a feedback capacity is reduced. In the above configuration, because a capacity between the emitter electrode 30 and a collector electrode 31 is also reduced, an output capacity Coes can be reduced. Further, the gate electrode 27 is formed to a position where the oxide film 26 is thinned at the bottom part. Therefore, the oxide film 26 between the gate electrode 27 and the bottom face of the groove 24 becomes thin, and thereby, a depletion layer immediately under the oxide film 26 becomes thick. 【課題】高速動作と耐圧の向上を両立する。【解決手段】図１の構造においては、酸化膜２６は、ゲート電極２７が形成された側面では一様に薄く、溝２４の底面中央側で厚く形成されている。この構造においては、ゲート電極２７が溝２４の底面側に形成されず、両側に分断され、底面電極２８がエミッタ電極３０と同電位とされるために、帰還容量が低減される。上記の構成においては、エミッタ電極３０・コレクタ電極３１間の容量も低減されるため、出力容量Ｃｏｅｓも低下させることができる。更に、ゲート電極２７は、この底部で酸化膜２６が薄くされた箇所まで形成されている。このため、ゲート電極２７と溝２４の底面との間の酸化膜２６は薄くなるために、この直下の空乏層は厚くなる。【選択図】図１