Patent ID: 11901414
Assignee: NXP B.V.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A bipolar transistor device comprising:
a semiconductor substrate that includes silicon;
a collector region, formed within the semiconductor substrate, wherein the collector region includes a first doped region formed in a lower portion of the collector region, a second doped region formed over the first doped region in an upper portion of the collector region, and a defect layer having an upper surface formed in an upper portion of the first doped region wherein the first doped region has a dopant concentration higher than a dopant concentration of the second doped region;
a base region formed over the collector region, wherein the base region includes single crystal silicon and germanium;
an emitter region formed over the base region, wherein the emitter region includes silicon; and
a spacer region formed below the base region and between the first doped region, the second doped region, and a collector region sidewall formed laterally adjacent the first doped region and the second doped region, wherein the spacer region includes a doping level below a doping level of the second doped region.