Analysis of efficiency limitations in high-low emitter back surface field silicon solar cells

Analytical and numerical models have been used to analyse the electrical behaviour of HLE-BSF n+-n-p-p+ silicon solar cells. It is shown that this structure should have lower open-circuit voltage values than the simple HLE solar cell due to the recombination current in the p+ region. Back surface passivation is proposed as a means to improve the Voc, that can be as high as 650 mV.