| 摘要 |
<p>A heterojunction bipolar transistor includes a collector contact layer, a collector layer, a base layer, and an emitter layer laminated in this order on the front surface of a compound semiconductor substrate, a collector electrode disposed on the collector layer, a base electrode disposed on the base layer, an emitter electrode disposed on the emitter layer, and an insulating film produced on the collector electrode and the base electrode burying those electrodes with the front surface thereof being flat. The front surface of the emitter electrode positioned uppermost among surfaces of the three electrodes is on the same plane as the flattened front surface of the insulating film and a wiring is directly produced on the emitter electrode. Thus, this HBT has no step difference between etched surfaces, and the wiring is produced by repeating sputtering of Ti/Au and Ar<+> ion-milling. Therefore, the wiring for the emitter electrode can be formed easily and minutely at high preciseness. In addition, the collector electrode is produced by evaporation and lift-off after required portions of the base layer and the collector layer are removed by dry-etching and a little wet-etching, so that the collector electrode can be produced with generating no burr. <IMAGE></p> |
