Patent attributes
A lateral heterojunction bipolar transistor is formed on a substrate including a top semiconductor layer of a first semiconductor material having a first band gap and of a first conductivity type. A stack of an extrinsic base and a base cap is formed over the top semiconductor layer. A dielectric spacer is formed around the stack. Ion implantation of dopants of a second conductivity type is performed to dope regions of the top semiconductor layer that are not masked by the stack and the dielectric spacer, thereby forming an emitter region and a collector region. A second semiconductor material having a second band gap greater than the first band gap, having a doping of the second conductivity type and being lattice matched to the first semiconductor material is selectively deposited to form an emitter contact region and a collector contact region, respectively.