Effect of carbon containing SiN x antireflection coating on the screen‐printed contact and low illumination performance of silicon solar cell

Screen‐printed metal contact formation through a carbon containing antireflection coating was investigated for silicon solar cells by fabricating conventional carbon‐free SiN x and carbon‐rich SiC x N y film. An appreciable difference was found in the average shunt resistance ( R sh ), which was about an order of magnitude higher for SiC x N y ‐coated solar cells relative to the counterpart SiN x ‐coated solar cells. Series resistance ( R s ) and fill factor ( FF ) were comparable for both antireflection coatings but the starting efficiency of SiC x N y ‐coated cell was ~0·2% lower because of slightly inferior surface passivation. However, SiC x N y ‐coated solar cells showed less degradation under lower illumination (<1000 W/m 2 ) compared with the SiN x ‐coated cells due to reduced FF degradation under low illumination. Theoretical calculations in this paper support that this is a direct result of high R sh . Detailed photovoltaic system and cost modeling is performed to quantify the enhanced energy production and the reduced levelized cost of electricity due to higher shunt resistance of the SiC x N y ‐coated cells. It is shown that R sh value below 30 Ω (7000 Ω cm 2 for 239 cm 2 cell) can lead to appreciable loss in energy production in regions of low solar insolation. Copyright © 2011 John Wiley & Sons, Ltd.