| 摘要 |
PROBLEM TO BE SOLVED: To improve some of requirements in design for impact ionization of a semiconductor device and a breakdown characteristic, incompatible with each other, by so forming a semiconductor structure that Brillouin zone average energy band gap is controlled based on an avalanche breakdown characteristic. SOLUTION: This structure consists of a substrate 1, a channel layer 2, a supply layer 3, n<+> source and drain contact areas 4, 5 and gate 6, source and drain electrodes 7 and 8. The channel layer 2 contains a low electric field 2a and a high electric field 2b formed by materials different from each other in Brillouin zone average energy band gap <Ec>. In the high electric field 2b, a value of <Ec> is so selected as to be relatively high, for avoiding risk of avalanche breakdown under an effect of the electric field generated under the gate 6. The material for the low electric area 2a is so selected as to contain a band gap of low value for maximizing effective carrier speed under the gate. |
