| 摘要 |
PURPOSE:To enhance breakdown strength between a gate and a drain by providing at least other Schottky gate electrode in a conductively active layer. CONSTITUTION:A source electrode 1, a first gate electrode 2 and a drain electrode 3 are provided on a conductively active layer 5 on a semi-insulating buffer layer 6, and a second gate electrode 2' is formed on the layer 5. Accordingly, a drain current flowing from the electrode 3 toward the electrode 1 in the layer 5 flows between depleted layers 4 and 4', and the drain current becomes the amplitude substantially proportional to the thickness of a channel region. When a second gate electrode 2' is further buried in the layer 5, the portion of the effective thickness of the active layer to be controlled by three Schottky junction surfaces of the electrodes 2, 2' are equally divided into three. Thus, a field-effect transistor having sufficiently high drain breakdown strength sufficiently large drain saturated current, high frequency and high output is obtained. |
