Super Critical Fluid Technique to Enhance Current Output on Amorphous Silicon-Based Photovoltaic

Abstract

A low temperature, non-destructive treatment technique with supercritical carbon dioxide mixing water was demonstrated on thin film type photovoltaic devices to enhance current output. Assembled P-I-N amorphous Si-based devices were treated in a high pressure reaction chamber. Generation of light current under indoor illumination was improved by about 80% after treatment. To clarify the origin of improvement, the drive-level capacity profiling method with capacitance–voltage (C–V) measurement was used, as it shows the relationship between defect density and location. Such measurements reveal that the amount of interface defects was significantly reduced after treatment. A dynamic reaction model was also proposed to explain the defect passivation reaction. This technique can be effectively applied to amorphous silicon solar cell devices to enhance performance.