Metal—Semiconductor Contacts

Abstract

In this chapter, we are concerned with the basic physical principles, electrical properties, and applications of the metal-semiconductor contacts and devices. It is well known that the quality of metal-semiconductor contacts plays an important role in the performance of various semiconductor devices and integrated circuits. For example, good ohmic contacts are essential for achieving excellent electrical characteristics of a semiconductor device, while Schottky (i.e., rectifying) contacts can be used for a wide variety of device applications. In addition to a wide variety of device and circuit applications, Schottky barrier contacts can also be used as test vehicles for investigating the physical and electrical properties of a semiconductor material and its surfaces. For example, a Schottky diode can be used to study bulk defects and interface properties of a metal-semiconductor system. Therefore, it is essential to obtain a better understanding of the fundamental physical and electrical properties of the metal-semiconductor interface so that technologies for preparing good ohmic and Schottky contacts can be developed for device applications.