Flow-rate modulation epitaxy of GaAs and AlGaAs

Flow-rate modulation epitaxy (FME) is a new epitaxial growth method which can produce a very flat heterointerface and a sharp doping profile. This paper describes FME growth conditions and electrical and optical properties of FME-grown GaAs, AlGaAs layers, and GaAs/AlGaAs single-quantum-well heterostructures. FME can reduce growth temperatures without deteriorating the crystalline quality and can produce flatter heterointerfaces than the metalorganic chemical vapor deposition method. The catalytic decomposition of silane on the Ga atomic surface efficiently dopes silicon into GaAs and AlGaAs with sharp profiles. For p-type doping, trimethyl metalorganic sources produce carbon atomic layer doping with no memory effect and a low diffusion coefficient of carbon. Experiments using FME to grow modulation doped heterostructures and heterostructure bipolar transistors prove FME to be a promising method of producing III-V semiconductor devices with thin-layered structures.