Abstract
Interdigitated Back Junction (IBJ) solar cells are suited to be realized on thin wafers, since they need a combination of high diffusion lengths and thin substrates. Here we present an industrial type passivation stack at the rear surface of an IBJ solar cell, consisting of a low quality SiO2 and a SINx layer, which has proven its value in the i-PERC concept developed at IMEC. Quasi-Steady-State Photo Conductance (QSSPC) lifetime measurements indicate an improvement of lifetime from 10 mu s to 180 mu s after application and rapid thermal processing (RIP) of the industrial passivation stack. For the IBJ solar cell concept without back surface field (BSF); this results in an absolute increase in energy conversion efficiency of 2% absolute, going from 14% to 16% and with a BSF up to 18%. Out of the presented cell data we can conclude the excellent passivation quality of the applied industrial passivation stack.