a-Si:H/TCO contact resistance measurement using a Kelvin cross bridge resistor

Abstract

Many have studied and reported properties of silicon heterojunctions solar cells in great detail, including open-circuit voltage and short-circuit current losses. However, little investigation has been dedicated to studying the series resistance contributions, especially at the maximum power point. Contact resistance between amorphous silicon and a transparent conductive oxide can have a significant contribution to series resistance, especially in silicon heterojunction solar cells. We propose the use of Kelvin cross bridge resistors to accurately measure the contact resistance between the doped amorphous silicon layer and the transparent conductive oxide layer typically found in a silicon heterojunction solar cell. This method allows an accurate measurement of the contact resistance without the interference of the sheet resistance of the highly resistive amorphous silicon layer.