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

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.