Patent ID: 6977426

Claim:
A semiconductor device having a first vertical type bipolar transistor and a second vertical type bipolar transistor each transistor having an emitter, a base, and a collector, the semiconductor device comprising: a P-type substrate; an N-type epitaxial layer formed on the substrate; a first embedded diffusion layer formed as a part of the collector of the first vertical type bipolar transistor in a first upper part of the substrate and in the epitaxial layer; and a second embedded diffusion layer formed as a part of the collector of the second vertical type bipolar transistor directly on the substrate, in a second upper part of the substrate, wherein a top of the second embedded diffusion layer is formed at a distance from a surface of the emitter of the second vertical type bipolar transistor greater than a distance between a top of the first embedded diffusion layer and a surface of the emitter of the first vertical type bipolar transistor, and a bottom of the second embedded diffusion layer is formed at a distance from the surface of the emitter of the second vertical type bipolar transistor greater than a distance between a bottom of the first embedded diffusion layer and the surface of the emitter of the first vertical type bipolar transistor; wherein the collector of the first vertical type bipolar transistor has a thickness that is less than a thickness of the collector of the second vertical type bipolar transistor, which results in the second vertical type bipolar transistor having a breakdown voltage that is higher than a breakdown voltage of the first vertical type bipolar transistor.