Identifying Electronic Properties Relevant to Improving the Performance and Stability of Amorphous Silicon Based Photovoltaic Cells: Final Subcontract Report, 27 November 2002--31 March 2005

Technical Report · Tue Nov 01 00:00:00 EST 2005

DOI:https://doi.org/10.2172/860393· OSTI ID:860393

Cohen, J D

A major effort during this subcontract period has been to evaluate the microcrystalline Si material under development at United Solar Ovonics Corporation (USOC). This material is actually a hydrogenated nanocrystalline form of Si and it will be denoted in this report as nc-Si:H. Second, we continued our studies of the BP Solar high-growth samples. Third, we evaluated amorphous silicon-germanium alloys produced by the hot-wire chemical vapor deposition growth process. This method holds some potential for higher deposition rate Ge alloy materials with good electronic properties. In addition to these three major focus areas, we examined a couple of amorphous germanium (a-Ge:H) samples produced by the ECR method at Iowa State University. Our studies of the electron cyclotron resonance a-Ge:H indicated that the Iowa State a Ge:H material had quite superior electronic properties, both in terms of the drive-level capacitance profiling deduced defect densities, and the transient photocapacitance deduced Urbach energies. Also, we characterized several United Solar a Si:H samples deposited very close to the microcrystalline phase transition. These samples exhibited good electronic properties, with midgap defect densities slightly less than 1 x 1016 cm-3 in the fully light-degraded state.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC36-99-GO10337
• OSTI ID: 860393
• Report Number(s): NREL/SR-520-38676; ADJ-2-30630-17; TRN: US0504907
• Resource Relation: Related Information: Work performed by the University of Oregon, Eugene, Oregon
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
43 PARTICLE ACCELERATORS
ALLOYS
CAPACITANCE
CHEMICAL VAPOR DEPOSITION
DEFECTS
DEPOSITION
ELECTRON CYCLOTRON-RESONANCE
GERMANIUM
IOWA
PERFORMANCE
PHOTOVOLTAIC CELLS
SILICON
STABILITY
TRANSIENTS
PV
MODULE
SOLAR CELL
THIN FILM
AMORPHOUS SILICON
DRIVE-LEVEL CAPACITANCE PROFILING (DLCP)
MODULATED PHOTOCURRENT SPECTROSCOPY (MPS)
ELECTRONIC PROPERTIES
ELECTRON CYCLOTRON RESONANCE (ECR)
HOT-WIRE CHEMICAL VAPOR DEPOSITION
TRANSIENT PHOTOCAPACITANCE (TPC)
Solar Energy - Photovoltaics