Optimization Parameters of Femtosecond Laser Isolation Processing for a Microcrystalline Silicon Thin Film Solar Cell

Abstract

This study explored the isolation process of a laser used to scribe the thin film layers of a microcrystalline silicon thin film solar cell. Using the Taguchi quality design, this study employed an L ₁₈ orthogonal array to plan and implement an experiment for an isolation scribing process using a femtosecond laser. The isolation scribing materials included ZnO:Al, 500 nm–thick AZO transparent conductive thin film, 500 nm–thick microcrystalline silicon thin film with 38% crystallinity, and 300 nm–thick aluminum back-contact film. The results indicated that the fair processing quality characteristics included the minimum scribing line width, the flattest trough bottom, and the least number of surface bumps on the processing edge. The optimal single quality characteristic parameters of the Taguchi quality design were obtained using main effect analysis and the analysis of variance (ANOVA). The analytic hierarchy process (AHP) theory was applied to determine the optimal parameters for the multiple quality characteristics of the isolation scribing process. When the integrated isolation scribing line width of various layers was thinner, the area occupied on the solar cell was smaller, thus directly enhancing the photoelectric efficiency of the solar cell.

Keywords:

• Isolation
• Laser
• Optimization
• Solar

Notes

^*1CAPD: Cathodic arc plasma deposition.

^*2HDPCVD: High density plasma chemical vapor deposition.

*AZO (500 nm)/ µc-Si (38% crystallinity, 500 nm)/Al (300 nm).

Unit: micron.