| 摘要 |
PROBLEM TO BE SOLVED: To provide a field effect transistor with high cut-off frequency. SOLUTION: The field effect transistor includes a semiconductor layer 13 containing an oxide, and a protective layer 16 of the semiconductor layer. An etching rate of the semiconductor layer to the following A or B is 1/2 of an etching rate of a silicon dioxide or below. A is a wet etching liquid containing a hydrofluoric acid of 10 mass%, and B is a wet etching liquid containing an ammonium fluoride of 15 mass%. COPYRIGHT: (C)2010,JPO&INPIT |
