Laser Cutting and Micromachining for Localized and Targeted Solar Cell Characterization
Steve Johnston1, Dana B. Sulas1, George F. Kroeger2
1National Renewable Energy Laboratory, Golden, CO, United States
/2Kroeger Inc., Phoenix, AZ, United States

Laser cutting and micromachining can be applied to solar cell materials for processing and characterization applications.  An ultrashort pulse (USP) laser with sub-picosecond pulse width can remove material with minimal thermal effects or damage, which is termed ‘cold ablation’.  Such USP laser cutting and scribing can be implemented for isolating areas within a larger cell while maintaining electrical performance and preventing laser-induced damage and shunting.  Laser micromachining has been used to isolate a shunt to improve cell performance and to isolate a small, selected area to define a sample suitable for deep level transient spectroscopy.