Multifunction metrology platform for photovoltaics

Advanced characterization for PV is a complex process that must address bulk defects, interfaces, passivation, and degradation phenomena. It requires not only appropriate measurement techniques, but also a coupling of measurements with treatments altering defect/interface activity. Preferably, the metrology should be noncontact and cost effective. The purpose of this work was to provide such multifunction wafer scale characterization capability for silicon PV. In this paper we describe a multifunction metrology platform. Example applications are given that illustrate the importance of sequenced measurements for 1 - monitoring of the light induced degradation in PV wafers and solar cells; 2 - correlation between interface trap density and surface recombination and the role of surface barrier, and 3 - monitoring of the field-effect potential emitter passivation.