TABLE OF CONTENTS Although the basic process of MBE, ultrahigh vacuum evaporation, had been in practice long before, it was not until the works of Arthur[1] and Cho[2] that a fundamental understanding of the process as applied to compound semiconductor growth evolved. Using mass spectrometric and surface analytical techniques, they studied the film growth process of gallium arsenide at the atomic layer level. Their work set the stage for equipment design specific to UHV epitaxial film growth. Subsequently, Chang et al.,[3] and others further advanced the process toward what we recognize today as MBE. The foundation of MBE is rooted in surface analysis and in understanding on an atomic level the nature of epitaxial film growth. Several reviews are of historical and technical significance; for instance, see Cho and Arthur,[4] Chang and Ludeke,[5] Foxon and Joyce,[6] Wood,[7] and Kunzel.[8] MBE equipment development still reflects the strong influence of its surface analytical beginnings. Subsequent advances in equipment design were made by Luscher and Collins[9] and others. The development of new and higher performance devices using MBE has advanced its commercial value. Present trends, reflecting the evolution of MBE from basic research to device production, are redefining and refining the equipment for specific material and device requirements.
A functional schematic of a MBE system is shown in Fig. 1. It consists of a growth chamber and auxiliary chamber (not present with first generation systems) and a load-lock. Each chamber has an associated pumping system. The load-lock facilitates the introduction and...
