ABSTRACT
This chapter discusses a high resolution scanning Kelvin probe to perform dark surface potential topographies of multicrystalline silicon solar cells having thin coatings of Si3N4 and SiO2. The development of multi crystalline silicon (mc-Si) with screen printed contacts is essential for mass production of inexpensive solar cells. Current mc-Si solar cell efficiencies are about 12-15% compared with up to 29% for sc-Si. Illumination of the substrate by photons of greater than band-gap light energy produces the surface photovoltage (SPY), A thorough review of the technique has been published by Kronik Land and Y. Shapira. The main reason for this difference relates to the defects introduced during the manufacturing process, including grrun boundaries, dislocations, interface trapped charge, metal impurities, resistance losses, and lattice strain. The chapter provides a procedure allowing unambiguous deconvolution of the SPY response into bulk effects occurring at the buried pn junction, such as the open circuit voltage, and interface charge trapping dynamics occurring in the passivation.
