| 摘要 |
PURPOSE:To reduce collector series resistance, and to enhance a gain-bandwidth product at a bipolar semiconductor device using an Si substrate by a method wherein a hole to reach a buried layer of reversely conductive type from the substrate is dug in a collector electrode lead out region, and an electrically low resistance material is filled up therein. CONSTITUTION:An N type buried layer 6 is formed by diffusion on the surface layer part of a P type Si substrate 11, an N type layer 4 is grown epitaxially on the whole surface containing the buried layer thereof, and the layer 4 is isolated containing the layer 6 into two regions according to SiO2 films 1. Then a P type base region 3 is formed by diffusion on the isolated region on one side, an N type emitter region 2 is provided therein, and a hole 7 to reach the buried layer 6 is formed in the region on another side according to reactive ion etching, etc. After then, the hole 7 thereof is buried with an Al electrode 8 to be connected to the buried layer 6, and at the same time, openings are dug in an insulating film covering the upper part of the regions 3, 2, and Al electrodes 8 are fixed respectively to the regions 3, 2. |
