Bipolar transistor structure with reduced collector-to-substrate capacitance

摘要

A pre-processed substrate structure for a semiconductor device. A subcollector layer is spaced apart from a substrate by a dielectric. A relatively small, lightly-doped epitaxial feed-through layer extends through the dielectric between the substrate and the subcollector. A transistor constructed over the subcollector has very low collector-to-substrate capacitance. A plurality of devices on a common substrate are electrically isolated from each other by channel stops formed in the substrate around each device.