Laser Sources For Next-Generation Solar Cells

By Finlay Colville, Coherent, Inc.

As solar cell and panel manufacturers emerge from the credit crisis, new process tools are set to enter production lines for increased module efficiency. This market-driven pull demands improved laser-based process tools and a broader range of laser types than used historically by the solar industry. Final laser source selection depends ultimately on a range of different factors being satisfied.

Introduction

Laser sources and laser-based process tools have been employed consistently during the past decade for a variety of production stages within the manufacturing of both crystalline silicon (c-Si) and thin-film solar cells and panels. Consequently, a diverse range of applications can be found within many of the review articles published recently covering lasers within the solar industry. However, some of the applications appear to have different sources recommended for the same basic process. In fact, as more laser source and tool manufacturers are attracted by the potential revenues associated with the high-growth status of the solar industry, the match between qualified laser process and tangible market-pull can often appear rather confusing.

This article explains the fundamental drivers that form the basis of laser source adoption within the solar industry. Where is the "pull"? What are the timescales involved? Why have certain laser sources been prioritized within production lines to date? And what are the trends that are most likely to change the equipment-type landscape during the next 10 years?