PULSED-JET EPITAXY - APPLICATION TO DEVICE PROCESSES

We report recent activities in the application of pulsed-jet epitaxy ( PJE), our new type of atomic layer epitaxy, to device processes. We di scuss three major factors of PJE; excellent uniformity of thickness an d interface controllability, low-temperature growth and heavy doping, and selective epitaxy. To study the degree of thickness control, we co mpare the thickness profile of the GaAs epitaxial layer between PJE an d MOVPE. The inherent ability of PJE to make a uniform layer is clarif ied. We find good thickness and interface control of PJE also in the s uccessful fabrication of InAs/InP and GaAs/GaP short-period strained-l ayer superlattices. Making use of the low-temperature growth and high- concentration Be doping into PJE-grown InGaAs, we fabricate the InGaAs /InP heterojunction bipolar transistor (HBT) structures using a novel PJE/MOVPE hybrid growth process. We show that PJE is a key technology used for making a high-performance HBT. The selective growth of PJE-Ga As shows ideal features in both morphology and thickness uniformity. A s an application, we report the formation of a nonalloyed contact laye r using selective regrowth of GaAs on a processed substrate.