RECENT IMPROVEMENTS IN THE SCREENPRINTING TECHNOLOGY AND COMPARISON WITH THE BURIED CONTACT TECHNOLOGY BY 2D-SIMULATION

Recently, a lot of progress has been made in the pilot-production of m ono- and multicrystalline silicon solar cells by the screenprinting te chnology. For example, a process based on screenprinting combined with oxide passivation and a plasma-nitride ARC yields cell efficiencies a pproaching 17% on 100 cm(2) Cz-Si material. These results ask for a de tailed comparison concerning the relative performance of state-of-the- art screenprinted cells compared to the state-of-the-art buried contac t structure. This is done by means of 2D-simulations using the simulat ion program SIMUL. It comes out that the efficiency difference between a buried contact technology and a screenprinting technology, both wit h selective emitter and good surface passivation, is only 0.5% absolut e. The efficiency difference between screenprinted cells with a homoge neous emitter and buried contact cells with a selective emitter turns out to be between 1 and 1.5% absolute, depending on the surface passiv ation quality. Looking at the above-mentioned difference in efficiency , only detailed cost calculations for an industrial production scenari o can reveal which process leads to the lowest cost per Wp.