This invention pertains to heterojunction bipolar transistors containing a semiconductor substrate, a buffer layer of an antimony-based material deposited on the substrate, a sub-collector layer of an antimony-based material deposited on the buffer layer, a collector layer of an antimony-based material deposited on the sub-collector layer, a base layer of an antimony-based material deposited on the collector layer, an emitter layer of an antimony-based material deposited on the base layer, and a cap layer of an antimony-based material deposited on the emitter layer.