Title :
Laser-doped silicon solar cells by Laser Chemical Processing (LCP) exceeding 20% efficiency
Author :
Kray, D. ; Alemán, M. ; Fell, A. ; Hopman, S. ; Mayer, K. ; Mesec, M. ; Müller, R. ; Willeke, G.P. ; Glunz, S.W. ; Bitnar, B. ; Neuhaus, D.H. ; Ludemann, R. ; Schlenker, T. ; Manz, D. ; Bentzen, A. ; Sauar, E. ; Pauchard, A. ; Richerzhagen, B.
Author_Institution :
Fraunhofer Institute for Solar Energy Systems, Heidenhofstr. 2, 79110 Freiburg, Germany
Abstract :
The introduction of selective emitters underneath the front contacts of solar cells can considerably increase the cell efficiency. Thus, cost-effective fabrication methods for this process step would help to reduce the cost per Wp of silicon solar cells. Laser Chemical Processing (LCP) is based on the waterjet-guided laser (LaserMicroJet®) developed and commercialized by Synova S.A., but uses a chemical jet. This technology is able to perform local diffusions at high speed and accuracy without the need of masking or any high-temperature step of the entire wafer. We present experimental investigations on simple device structures to choose optimal laser parameters for selective emitter formation. These parameters are used to fabricate high-efficiency oxide-passivated LFC solar cells that exceed 20% efficiency.
Keywords :
Chemical lasers; Chemical processes; Contact resistance; Etching; Metallization; Optical device fabrication; Photovoltaic cells; Semiconductor device doping; Silicon compounds; Solar energy;
Conference_Titel :
Photovoltaic Specialists Conference, 2008. PVSC '08. 33rd IEEE
Conference_Location :
San Diego, CA, USA
Print_ISBN :
978-1-4244-1640-0
Electronic_ISBN :
0160-8371
DOI :
10.1109/PVSC.2008.4922848