SOLASYS · Next generation solar cell and module laser processing systems

Laser processes provide manufacturing solutions with minimum mechanical and thermal influence on the processed product due to their selective energy control and deposition and generally high processing speed. With this advantages they are already well established for some processing steps in the current production of solar cells. High speed laser ablation is used for the isolation of the emitter front side from the backside of a solar cell, Laser melting is used to form backside contacts and laser drilling has been proven as a versatile tool for drilling silicon wafers for metal wrap through backside contacts. All these processes are currently performed with standard Q-switch-Nd:YAG-Lasers with pulse durations of up to 100 ns which provide process characteristics and results being far away from the technical and physical limits of possible laser processes. New laser sources such as ultra short pulsed lasers, time domain optimized lasers, wavelength adapted lasers and ultra compact modular laser sources have been recently developed and provide a much better matching of laser parameters to the required processing characteristics. With these new laser sources flexible manufacturing steps can be realized leading to higher productivity and production costs as well as to higher efficiency of solar cells and modules and even new cell concepts. Within a consortium from laser manufacturers, system suppliers, research institutes and end users the technical and physical potential of high quality and process tailored laser sources will be demonstrated throughout the project and evaluated for current and future photovoltaic manufacturing processes.