CWLS – Crystalline Wafer Laser Scriber System

The Crystalline Wafer Laser Scriber System (CWLS) is a picosecond laser-based ultrafast crystalline silicon solar cell processing system. It was designed for passivation layer patterning on passivated emitter rear contact (PERC) crystalline solar cells. Due to the short laser pulses (picoseconds range) the laser scribed back contacts have an excellent quality. The system was developed for fully automated process to be integrated in the crystalline solar cell manufacturing process.

The basic system is an off-line, semi-automated version (depicted above), requiring minor additional modifications to be able to be integrated to an automated PERC production line. Operation parameters, as well as the configuration of the desired ablation pattern are adjustable on a user-friendly GUI. Precise positioning of the ablation pattern is ensured by the automated alignment carried out the tools’ camera system.



Laser power: 15 W
Laser wave-length: 532nm (Green laser)
Pulse frequency: Single pulse up to 20 MHz
Electric power requirement: 26 kW
Voltage: 400V/230V / 50Hz/3 phases
Machine size (L × W x H): 2560 mm x 1000 mm x 2490 mm
Layout area (L × W x H): 3240 mm × 1930 mm × 2490 mm
Mass: 1400 kg
Wafer type: Multilayer wafers
Wafer size: 6”; 156 mm x 156 mm
Throughput in fully automated mode: 1600 pcs / hours
Pico-laser unit for thin-layer ablation
High-precision positioning system
Camera system for surface and position inspection
High-speed rotary-table unit
Exhaust system with air-knife and filter for removing the ablated particles
Viewport for process control
Touch-screen monitor
Automatic door unit with safety system
Granite baseplate for stability
Vacuum system for wafer fixing
Laser protection: Class 4
User-friendly GUI