| 摘要 |
PURPOSE:To enable to form a longitudinal PNPTr which is not substantially different from a longitudinal NPNTr in an area manner in the same degree as the longitudinal NPNTr in high frequency characteristic by forming the longitudinal NPNTr and the longitudinal PNPTr on an insular region isolated between elements by the first insulating film in the same step. CONSTITUTION:A portion that an N<+> type buried layer 22 becomes an insular region is formed on a P type semiconductor substrate 21, and a high density P type region 23 is formed in a longitudinal NPNTr only on an interelement isolating region, and in a longitudinal PNPTr on an interelement isolating region and an insular region. An interelement isolating oxidized film 28 and an oxidized film 28' for isolating between the collector contact and the base regions of the NPNTr are formed, an isolating oxidized film 34 between the emitter and the base is formed in the NPNTr and an oxidized film 35 is formed in the PNPTr on the periphery of the emitter by selective oxidation. At this time, the former is shallow, and the latter is deep. High density P<+> type regions 37a, 37b, 37c are formed, an inert base is formed in a self-aligning manner from the end of the emitter in the NPNTr, and the emitter, collector contact are formed in the PNPTr. |
