Title :
Float-zone and Czochralski crystal growth and diagnostic solar cell evaluation of a new solar-grade feedstock source
Author :
Ciszek, T.F. ; Page, M.R. ; Wang, T.H. ; Casey, J.A.
Author_Institution :
Nat. Renewable Energy Lab., Golden, CO, USA
Abstract :
Czochralski (CZ) and float-zone (FZ) crystals were grown from experimental solar-grade silicon (SoG-Si) feedstock materials developed by Crystal Systems. The materials were metallurgical-grade Si and highly boron-doped p-type electronic-grade Si (EG-Si) reject material, both of which were gaseous melt-treated to remove boron. Crystal growth observations, lifetime and impurity characterization of the grown crystals, and device performance of wafers from them are presented. Devices made directly on treated high-B EG-Si feedstock have a little over half the efficiency of devices made from control CZ samples. However, devices on CZ and FZ crystals grown from the treated high-B EG-Si feedstock have comparable PV performance (14.0% and 13.8% efficiency, respectively) to that of CZ control samples (14.1%).
Keywords :
crystal growth from melt; elemental semiconductors; semiconductor device measurement; semiconductor growth; silicon; solar cells; zone melting; 13.8 percent; 14.0 percent; 14.1 percent; Czochralski crystal growth; PV performance; Si; diagnostic solar cell evaluation; efficiency; float-zone crystal growth; highly boron-doped p-type electronic-grade Si; metallurgical-grade Si; solar-grade feedstock source; Boron; Crystalline materials; Crystals; Etching; Feeds; Impurities; Inorganic materials; Photovoltaic cells; Renewable energy resources; Silicon;
Conference_Titel :
Photovoltaic Specialists Conference, 2002. Conference Record of the Twenty-Ninth IEEE
Print_ISBN :
0-7803-7471-1
DOI :
10.1109/PVSC.2002.1190493
