| 摘要 |
PURPOSE:To form selectively an external base layer and a semi-insulating region positioning directly thereunder, and moreover to form by selgalignment an emitter electrode by a method wherein the semi-insulating region and the external base layer are grown epitaxially in order, then mesa-etching is performed selectively, an inner base layer and an emitter layer are epitaxially grown selectively in order, and the emitter electrode is formed by selfalignment. CONSTITUTION:A subcollector layer 2, a collector layer 3, a semi-insulating region 8, and an external base layer 7 are grown epitaxially in order on a semi-insulating substrate 1. Then after the corresponding portion of a deposited insulating film 14 is opened 14a selectively, the external base layer 7 and the semi-insulating region 8 are removed according to mesa-etching up to reach the collector layer 3 using the insulating film pattern thereof as a mask. Then epitaxial growth is performed selectively only to the mesa-etched part to form an inner base layer 4, an emitter layer 5 and a cap layer 6 respectively. By utilizing the opening 14a of the insulating film 14 in succession, an emitter electrode 11 is formed by selfalignment to obtain the desired constitution.
|
