Laser assisted molecular beam epitaxy (LAMBE) of compound semiconductor buffer layers and AlN, GaN structures for high electron mobility transistor

Rapid thermal processing (RTP) in the compound semiconductor technology has had a significant impact in making such a technology reliable and manufacturable. Since 1980, RTP has been applied to achieving control of doping profiles, achieving implant activation and the application of advanced metallization systems. Since 1990, RTP in the form of pulsed excimer laser processing has been applied to molecular beam epitaxial growth (MBE) for the development of high resistivity buffer lasers and for achieving the heterostructures necessary for high electron mobility transistors (HEMTs). The emphasis in the present paper is to review the GaAs device technology, the material problems and device structures and to show that RTP has removed key material problems which were bottlenecks in achieving a fabrication process which is reliable and high yield. The technique has been extended to nitrides and through laser assisted MBE (LAMBE), state of the art GaN and AlN layers have been grown for GaAlN based HEMTs.