| 摘要 |
PURPOSE:To contrive to improve the frequency characteristic by shortening the clearance between an emitter layer and a base electrode lead-out layer by a method wherein the base electrode is led out on an insulation isolation film adjacent to a base layer by means of a double layer of poly Si and metallic silicide. CONSTITUTION:The p-base 61 is formed by opening windows through the oxide film on an isolatated n<-> collector layer 3 of a p<-> type Si substrate 1 and then superposing a p-type poly Si 601, the film 601 is selectively left, SiO2 105 and 106 are provided, and a Si3N4 202 is superposed. An emitter 7 and an n<+> collector lead-out layer 8 are formed by using resist masks 302 and 303. A Ti2Si 501 is formed by laminating a Ti 500 and a Pt 700. The Pt 700 and the Ti 500 are removed, covered with a PSG401, windows are opened by applying a resist mask 304, and then Al electrodes 9-11 are formed. Since the base electrode 9 is led out on an isolated oxide film adjacent to the base 62, the base resistance is reduced by making the base electrode lead-out region close to the emitter layer 71, and the capacity CBC can be reduced by the omission of an external base, accordingly a device of good frequency characteristic can be obtained. |
