Development Status of the Electro-Thermal and Spatial Spectral Scanning System for Solar Cells

摘要

Electro-thermal infrared scanning is a new method for detecting local differences in diode parameters. This method uses an infrared scanner to map small increases in local surface temperatures of a diode after applying a bias voltage. The feasibility of this method has been demonstrated for diodes reverse biased beyond the breakdown voltage. An electro-thermal solar cell scanning system is being developed which should have high enough sensitivity to detect local differences within diodes biased at voltages more positive than the reverse breakdown. This system, applied to solar diodes over their entire range of operation, is expected to be a powerful tool for use in developing solar cells and possibly for correcting some types of production line difficulties. A second new method, the spatial spectral scanner, is also being incorporated in the electro-thermal system to give further information on spatial variations within solar cells. This method scans the solar cell with a minute spot of variable frequency light while the cell's output current is recorded, ad will augment information from the electro-thermal system. (ERA citation 06:010511)