| 摘要 |
PURPOSE:To reduce dispersion in a chip of threshold voltage, and to prepare an integrated circuit easily by using a field-effect transistor, in which the ions of an N type impurity are implanted to a GaAs semi-insulating semiconductor substrate containing a neutral impurity and the N type impurity is activated through heat treatment at a high temperature to form an operating layer, as a constitutional element. CONSTITUTION:The ions of <28>Si as an N type impurity are implanted to a surface section 11 in a GaAs semi-insulating semiconductor substrate 10 containing In as a neutral impurity. A striped pattern 12 coating the position of a gate electrode is formed, and the ions of <28>Si are implanted to sections 13, 14 while using the pattern 12 as a mask. The resist mask 12 is removed, an silicon nitride film is deposited on a crystal surface, and an ion implanted layer is activated through heat treatment in an N2 atmosphere while employing the silicon nitride film as a protective film. The silicon nitride film is removed, and a source electrode 16, a drain electrode 17 and a gate electrode 18 are formed. |
