Molecular Beam Epitaxy of III-V Compounds: Application of MBE-Grown Films

The performance of devices fabricated from materials grown by molecular beam epitaxy (MBE) can ideally be used to judge this new film growth technique. From the beginning, microwave and optoelectronic devices have been fabricated from MBE-grown GaAs and AlxGa1_xAs. Initially this work was done mainly at Bell Telephone Laboratories. Fabrication and performance of various devices obtained from MBE material were summarized in excellent reviews by Cho & Arthur (1) and by Cho (2). In the first decade, emphasis was on the MBE production of standard device structures exhibiting characteristics comparable with or even superior to those fabricated by the more conventional growth and processing techniques. Excellent results were obtained for MBE-grown GaAs devices including varactor diodes (3-5), mixer diodes (5, 6-9), IMPATT diodes (10), Gunn diodes (11), MESFETs (12-17), optical waveguides (18-23), and DH injection lasers (24-46). The unique features of MBE have been further applied to more complex device structures involving novel processing steps such as lateral dimensional control as well as metal-semiconductor and oxide-semiconductor heterojunction formation in a single growth cycle. The limits of the MBE technique for the production of novel device structures have not yet been reached.