By Monica Aleman, IMEC; Angel Uruena, Silicon PV Research Scientist, IMEC; Emanuele Cornagliotti, Researcher, IMEC; Aashish Sharma, IMEC; Richard Russell, IMEC; Filip Duerinckx, IMEC; Jozef Szlufcik, Director of the Photovoltaics Department, IMEC
This paper presents the main features of imec’s n-PERT (passivated emitter rear totally diffused) cells, which have achieved independently confirmed efficiencies of 22%. A special focus is given to the selective front-surface field formation by laser doping, which – combined with imec’s front-plating sequence and the excellent rear-surface passivation by Al2O3 on the boron-diffused emitters – has enabled very high voltages (close to 685mV) to be realized on large-area n-type Cz material.