CIGS thin-film solar module processing: case of high-speed laser scribing

Area of Science:

• Photovoltaics
• Materials Science
• Laser Processing

Background:

• Copper Indium Gallium Selenide (CIGS) thin-film solar cells are a key technology in renewable energy.
• High-speed manufacturing processes are essential for scaling up photovoltaic production.

Purpose of the Study:

• To investigate ultra-short pulsed laser scribing of CIGS solar cells at high speeds.
• To evaluate different P3 scribing approaches and their impact on device performance.
• To identify reliable methods for terawatt-scale CIGS solar cell manufacturing.

Main Methods:

• Utilized an ultra-short pulsed laser with a 1 MHz repetition rate.
• Investigated two P3 scribing methods: full layer ablation and front-contact removal.
• Evaluated scribe quality using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS).
• Performed electrical measurements and device electrical behavior modeling at the mini-module scale.

Main Results:

• High-speed laser processing at high pulse repetition rates induced thermal damage.
• Top-contact layer lift-off processing achieved 1.7 m/s scribing speed with minimal degradation.
• Ultra-high speed P3 processing reached scribing speeds of 50 m/s.
• Mini-module scribing tests confirmed the viability of selected laser processes.

Conclusions:

• Top-contact layer lift-off is the only reliable method for high-speed P3 laser scribing of CIGS solar cells.
• This technique is suitable for future terawatt-scale photovoltaic production.
• Optimized laser parameters are critical to minimize thermal damage during high-speed processing.