Soi bipolar transistors with reduced self heating

Abstract

A bipolar transistor includes a collector located over a substrate; and a heat conductive path connecting the substrate to the collector. The heat conductive path is filled with a heat conductive material such as metal or polysilicon. In one embodiment the heat conductive path runs through the collector to extract heat from the collector and drain it to the substrate. In alternate embodiments, the transistor can be a vertical or a lateral device. According to another embodiment, an integrated circuit using BiCMOS technology comprises pnp and npn bipolar transistors with heat conduction from collector to substrate and possibly p-channel and n-channel MOSFETS. According to yet another embodiment, a method for making a transistor in an integrated network comprises steps of etching the heat conducting path through the collector and to the substrate and fill with heat conductive material to provide a heat drain for the transistor comprising the collector.