ABSTRACT
Silicon molecular beam epitaxy (Si-MBE), that is, the epitaxy of silicon under ultrahigh vacuum conditions, may be considered to have started in the mid 1970s. However, this technique has not get gained as much popularity as III-V-MBE also initiated in the early 1970s. The reason for this difference is probably the existence of high performance alternatives to Si-MBE. This chapter describes some applications of the MBE specificity and advantage to devices otherwise obtainable by conventional techniques. The ability to form hyperabrupt impurity profiles during epitaxial layer growth eliminates the need of extensive heat treatment required in conventional processes. The main novel devices based on Si-MBE homoepitaxy are clearly the Si hot electron transistor and the nipi structures, though the potentiality of the latter is still controversial. In order to take full advantage of this opportunity, a low-temperature technology must be developed so that no doping smear-out occurs during processes.
