Nondestructive testing of semiconductor materials

摘要

An n-type region of a semiconductor body, such as a surface region of a bulk wafer or an epitaxial layer region grown on a wafer (12), is successfully submitted to a capacitance-voltage test using a mercury probe (11) after being subjected to a pretreatment. The pretreatment includes forming a thin oxide layer, preferably in the order of 10 to 20 Angstrom units thick, on the surface of the wafer (12), and pulsing the mercury into contact with the pretreated surface while a reverse bias voltage is applied between the mercury and the region. If a resulting reverse leakage current exceeds a desired current threshold value, the pulsing of the mercury into contact with the surface of the water (12) is repeated until a rectifying contact having a sufficiently low reverse leakage current through the mercury-to-semiconductor interface has been established.