Problems related to the formation of lateral p–n junctions on channeled substrate (100) GaAs for lasers

We shall describe the main steps required for molecular-beam epitaxial (MBE) growth on structured GaAs substrates for lasers, in particular, a reproducible etching process develolped for GaAs which yields well-defined and controllable tilt angles. The main parameters determining morphology and doping behavior on a facet are tilt angle Θ, substrate temperature, and the V:III ratio. The limiting values of these three parameters for obtaining good quality n- and p-type films, using Si as a dopant, will be determined. We conclude that a (311A) facet is best suited to obtain plane selective doping without generating a detrimental (111A) plane. As a result of this study, lateral p–n junctions with light emission will be demonstrated showing promise for new device structures such as lasers.