Title :
Assessment of MOCVD- and MBE-growth GaAs for high-efficiency solar cell applications
Author :
Tobin, Stephen P. ; Vernon, S.M. ; Bajgar, C. ; Wojtczuk, Steven J. ; Melloch, Michael R. ; Keshavarzi, A. ; Stellwag, T.B. ; Venkatensan, S. ; Lundstrom, Mark S. ; Emery, Keith A.
Author_Institution :
Spire Corp., Bedford, MA, USA
fDate :
2/1/1990 12:00:00 AM
Abstract :
A critical assessment of the photovoltaic quality of epitaxial GaAs grown by metal-organic chemical vapor deposition (MOCVD) and by molecular-beam epitaxy (MBE) is reported. Epitaxial films of nominally identical structure were grown by the two techniques and were fabricated into p-n heteroface solar cells. The 0.5-cm by 0.5-cm cells were then characterized and compared. The MOCVD-grown films produced independently verified record efficiency cells of 24.8% under 1-sun AM1.5 global conditions while the MB-grown films produced similarly high efficiencies of 23.8%. The material qualities of the two films in terms of minority-carrier diffusion lengths and surface recombination velocities were quite comparable. These results demonstrate that the quality of MBE-grown films can be quite comparable to the best MOCVD-grown films and that they are suitable for high-efficiency solar cells
Keywords :
III-V semiconductors; carrier lifetime; electron-hole recombination; gallium arsenide; molecular beam epitaxial growth; semiconductor epitaxial layers; semiconductor growth; solar cells; vapour phase epitaxial growth; 0.5 cm; 23.8 to 24.8 percent; III-V semiconductor; MB-grown films; MOCVD-grown films; VPE; epitaxial GaAs; high-efficiency solar cell applications; metal-organic chemical vapor deposition; minority-carrier diffusion lengths; molecular-beam epitaxy; p-n heteroface solar cells; photovoltaic quality; quality assessment; surface recombination velocities; Chemical vapor deposition; Crystalline materials; Furnaces; Gallium arsenide; MOCVD; Molecular beam epitaxial growth; Photovoltaic cells; Photovoltaic systems; Solar energy; Solar power generation;
Journal_Title :
Electron Devices, IEEE Transactions on
