Metal-Semiconductor-Junction is also called heterojunction since the
material on each side of the junction is not identical. The normal pn junction diode
concept can also be applied here. There are two probable types of metal semiconductor junctions: Schottky junction and ohmic junction. When the work function of metal is greater than the work function of a semiconductor, then this is
called Schottky junction. Ohmic junctions are the junctions in which the work
function of the metal is less than the work function of a semiconductor. Their band
engineering discussed in detail the essentials of junction physics.
Keywords: Band engineering, Heterojunction, Schottky contact, Ohmic contact.
