GOAL1
German Federal Ministry for Environment, Nature Conservation and Nuclear Safety
- GOAL1 - New innovative approaches for laser-based edge isolation, aiming at efficiency increase and cost decrease
- reduce cycling times from currently 2 seconds to 1 second
- reduce manufacturing costs
- minimize cracking rates
- increase the solar cell efficiency by at least 0,1 %
These aims of the project will each be realized by finding a “global solution”, consisting of a system for quick data preparation, a new adapted laser source, adapted laser beam guidance, as well as two laser edge isolation processes. A reduction of cycling times is accompanied by a reduction of manufacturing costs. Due to the minimized thermal damage of the solar cell, the cracking rate can also be minimized. Efficiency increase is mainly due to precise, edge-near and process safe isolation processes as the active surface of the solar cell can be used optimally. Realization is achieved by using shorter pulse durations so that the crystal structure is not damaged. For this purpose, laser beam sources with pulse lengths in the picosecond scale as well as with high pulse peak performance and high repetition rates are used.
The ability to focus precisely leads to a minimization of the edge gaps and dike widths. The simultaneously developed process allows cutting through the material entirely without any thermal damage and material removal. Thermally induced mechanic tension caused by laser radiation lead to a controllable crack progress along the solar cell edge, and guarantee a 100 per cent electrical isolation.
Project duration: 30 months (September 1, 2008 to February 28, 2011)
Project partners
- Schott Solar GmbH
- Manz Automation AG
- Trumpf Laser GmbH + Co.KG
- Laser Zentrum Hannover e.V. (Coordinator)