| 摘要 |
PURPOSE:To obtain an element having stable characteristics by providing a base electrode directly above a true base region, thereby minimizing the irregularity of a voltage between the base and the emitter. CONSTITUTION:Photoresist films 17, 18 are etched, a polycrystalline silicon film 7 is then anisotropically etched when the film 7 of a raised region is exposed, the film 7 is removed only on the upper surface of the raised region, and a silicon oxide film 14 is exposed. Then, the film 14 is removed, the film 7 is patterned to include a lateral transistor, and a pickup electrode is formed. Subsequently, boron is diffused from the layer 7 to the raised region to form P<+> type regions 41, 42. The remaining portion 111 of an Si-epitaxial layer 11 becomes an active region. Then, an insulating film 8 is formed by oxidizing, and a nitride film 13 is removed. Thereafter, a high density N<+> type base region 5 is formed by ion implanting. Subsequently, a nitride film 19 is accumulated, a hole for a base pickup electrode is opened, N type impurity is added to form a base pickup region 5. Further, the film 19 and an insulating film 8 are etched to form electrodes 91, 92. |
