Product Code: ICAL06_M704

Laser Technology for Cost Reduction in Silicon Solar Cell Production
Authors:
Aart Schoonderbeek, Laser Zentrum Hannover (LZH); Hannover Germany
Uwe Stute, Laser Zentrum Hannover (LZH); Hannover Germany
Andreas Ostendorf, Laser Zentrum Hannover (LZH); Hannover Germany
Rainer Grischke, Institut für Solarenergieforschung Hameln /Emmerthal (ISFH); Emmerthal Germany
Peter Engelhart, Institut für Solarenergieforschung in Hameln/Emmerthal (ISFH); Emmerthal Germany
Rüdiger Meyer, Institut für Solarenergieforschung Hameln/Emmerthal (ISFH); Emmerthal Germany
Rolf Brendel, Institut für Solarenergieforschung in Hameln/Emmerthal (ISFH) ; Hannover Germany
Presented at ICALEO 2006

During the last years, the photovoltaic solar cell industry has experienced enormous growth. However, for solar cells to be competitive on the longer term, both an increase in their efficiency as well as a reduction in their cost is necessary. Laser technology offers many opportunities to realize these improvements. Some of these will be discussed in this paper. Most solar cells are produced from silicon wafers, and the preferred method to reduce costs has been to reduce the thickness of the wafers involved. Consequently, contact and pressure-free laser processing has large advantages. In this paper, experimental investigations are discussed for producing grooves and holes in silicon wafers for a recently at ISFH developed solar cell concept. Damage of the silicon in the surrounding of the processing area should be avoided. Laser processing is studied with a variety of pulsed lasers like an excimer laser, a Nd:YAG laser and frequency converted solid state lasers with a variety of wavelengths. Also, for drilling holes, a CO2 laser is tested. Furthermore, the different types of lasers are not only compared regarding their processing quality, but also regarding speed and costs.