Methods for investigation of electrical contact resistance in a metal film--semiconductor structure

Abstract

The electrical contact resistance significantly affects the efficiency of thermoelements. In the case of high doped thermoelectric materials, the tunneling mechanism of conductivity prevails at metal-semiconductor interface, which makes it possible to obtain a contact resistance of less than 10-8 Ohm·m2. Low resistance values significantly complicate its experimental determination. Work present three techniques and a measuring stand for the investigation of contact resistance. The techniques are based on the measurement of the total electrical resistance, which consists of transient contact resistance and the resistance of the thermoelectric material with its subsequent exclusion. The developed techniques differ in the arrangement of the investigated contacts on the samples, in the methods of measurement and processing of the obtained results, and make it possible to determine the specific contact resistance of the order of 10-10 Ohm·m2. Keywords: thermoelements, film contacts, contact resistance, measurement techniques.