Latest Trends in Development and Manufacturing of Industrial, Crystalline Silicon Solar-Cells

Abstract

Abstract Reliability, performance and cost are the key parameters for all PV products. The technology dominating the PV market until today with a market share of ∼80% is the very robust and versatile double-side contacted silicon solar-cell. During previous years the development and manufacturing of this standard cell architecture has been very successful with respect to the continuous reduction of unit-cost and improvement in efficiency, maintaining its dominance in the PV arena despite a huge number of competing thick- and thin-film concepts and technologies. In this paper we present an overview about the ongoing development and manufacturing activities at Q-Cells, which show, that also for the next years to come, the continuous improvement of the standard cell architecture still has an enormous potential with respect to cost and efficiency and hence to €/Wp and finally €/kWh reduction. The main levers are the optimization of optical and electrical front side properties and the successful transfer of low cost backside passivation and metallization concepts from the R&D lab into pilot- and finally high volume production. We applied these well known concepts to our 6” p-type standard monoand multi-crystalline wafers including umg-Si. The results, achieved in our R&D Pilot Production facility at Thalheim, show stable median efficiencies exceeding 19% for our mono- and 18% for our multi-crystalline solar cells including umg-Si. These cells feature a lowly doped emitter, a fineline-printed Ag grid and a dielectric passivated rear with point contacts. Narrow efficiency distributions are achieved with help of laser marked single wafer tracking, enabling sophisticated equipment and process control. By applying advanced module manufacturing technologies to these high-efficient multi-crystalline cells we achieve module power output of > 260 Wp for a standard 60 cell module.