Photoelectrochemical capacitance-voltage measurements of wide bandgap semiconductors

摘要

A method of determining the carrier concentration depth profile in n- type wide bandgap semiconductor wafers is disclosed. The method includes placing a semiconductor wafer within a photoelectrochemical capacitance- voltage measurement system, in contact with a Schottky electrolyte solution. A high energy ultraviolet light is directed through the electrolyte solution to impinge upon the surface of the semiconductor wafer. The ultraviolet light has an energy greater than the energy bandgap of the semiconductor material and thus facilitates reliable etching thereof. The etch is allowed to continue until a desired depth in the sample is obtained. Upon cessation of the etch, the carrier concentration is determined. The steps of determining the carrier concentration and etching are repeated until the desired carrier concentration depth profile has been obtained.