| 摘要 |
<p>PROBLEM TO BE SOLVED: To lower capacitance and improve a high-frequency characteristic. SOLUTION: A gate electrode 16 is constituted by one or more bar gate electrodes 13, and it is supported by one or more supporting bars 14, then parts of the gate electrode 16 are arranged around the tips of emitter electrodes 12. Thus constitution of the gate electrode 16 lessens the area opposite to a substrate 11, to lower capacitance C. An gap is formed right under the gate electrode 16, thereby the dielectric constant is approximately 1, thus the capacitance C is also lowered. Consequently, transition frequency in inverse proportion to the capacitance C is heightened, to improve a high-frequency characteristic. Also, in the case of plural emitter electrodes 12, the bar gate electrodes 13 constituting the gate electrode 16 are coupled to each other. Thereby, a heavy current can be passed by one control signal. Thus, heavy current can be also realized in addition to the improvement of the high-frequency characteristic.</p> |
