The ability to cut, scribe, and drill holes and slots in silicon material is of great interest for many applications in the microelectronics and semiconductor industry. We investigated the use of a Q-switched frequency-tripled Nd:YAG laser for rapid micromachining of silicon and compared the results to results achieved with a pulsed fiber laser operating near 1060nm.

Multicrystalline Silicon was textured with picosecond laser. Different laser wavelengths (λ = 1064, 532, 355 nm) where compared regarding laser-induced damage. We found that λ = 355 nm picosecond radiation resulted in shallower defect-reach region.

Laser Edge Isolation is the main laser application in photovoltaic applications. This laser process is necessary to remove parasitic emitter diffusion wrapping around the wafer edge, in order to avoid very low fill factors. We have investigated in detail, and compared the results thus obtained, the cell surface scribing realized with State of the Art Pulsed Fiber Laser (emitting at about 1070 nm) and tripled ND:YAG (emitting at 355 nm).

Thanks to the rapid growth of the photovoltaic market the silicon demand is continuously increasing. The shortage of purified silicon between 2004 and 2008 induced a strong price increase and trigged a capacity expansion as well as the introduction in ingot production of the so called “upgraded metallurgic grade silicon” (UMG-Si) as feedstock. However, new solar grade silicon might contain significant higher fractions of impurities.

In this paper we report a novel laser shallow scribe approach where the material is not removed but a phase modification in the material is induced by pulsed IR Fiber Laser, a process named “extended P2”.