High throughput P2 laser scribing of Cu(In,Ga)Se₂thin-film solar cells

Abstract

Laser scribing is an indispensable step in the industrial production of Cu(In,Ga)Se 2 thin film solar modules. While cell separation (P1 and P3) is usually achieved using high velocity, low overlap lift-off processes, removal of the absorber layer for generating an electrical back-to-front interconnect (P2) is typically a slow process. In the present study we present an approach for scaling the classical P2 process velocity to an industrially exploitable level. We demonstrated successful P2 scribing at up to 1.7 m/s in a single beam, single pass configuration using a linear focal spot. The presented process is robust against variations in the scribing velocity and focal position, a key point for successful machine integration.

High throughput laser-scribing processes for industrial production of flexible CIGS thin-film solar modules

“…The scribing velocity scales approximately proportional to the aspect ratio: length to width of the focal line. Based on this technique linear scalability with laser pulse energy was demonstrated and scribing velocities up to 1750 mm/s were realized [5].…”