Gas-source molecular beam epitaxy (GSMBE) has been developed into a useful tool for the growth of both optical and electronic device structures. In this paper, we report on the use of tertiarybutylarsine (TBA) and tertiarybutylphosphine (TBP) in GSMBE for the growth of electronic device structures with state-of-the-art performance. Device structures based on both the In0.48Ga0.52P/GaAs and In0.53Ga 0.47As/InP lattice matched materials systems are described. The GSMBE system is based on the use of elemental Group-rn sources and employs thermal crackers for precracking TBA and TBP. Dopant sources include both elemental (Sn and Be) and vapor (CBr4 and SiBr4) sources. Device structures fabricated in the In0.48Ga0.52P/GaAs materials system include single- and double- heterojunction bipolar transistors (SHBTs and DHBTs). Device structures fabricated in the In0.53Ga0.47As/InP materials system include SHBTs, DHBTs, heterojunction field effect transistors (HFETs), and both planar and lateral resonant tunneling diodes (RTDs.) Vertically integrated HFET and multi-RTD heterostructures for high speed logic/memory are also described.