Influence of microstructure on the Urbach edge of amorphous SiC:H and amorphous SiGe:H alloys

Journal Article · Mon Oct 12 04:00:00 EDT 1987 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.98721· OSTI ID:6124636

Mahan, A H; Menna, P; Tsu, R

Infrared measurements have been used as a means of quantifying the amount of hydrogenated amorphous silicon and amorphous silicon alloy microstructure. Using a parameter obtained from these infrared measurements, the Urbach edge of amorphous silicon (a-Si:H), amorphous silicon carbon (a-SiC:H), and amorphous silicon germanium (a-SiGe:H) obtained from photothermal deflection spectroscopy measurements fall on the same curve. This suggests that the decreasing steepness of the Urbach edge, observed to occur with increasing alloying, is due primarily to microstructural effects and not to increased structural or compositional disorder. Based upon this correlation, we suggest an explanation for the observed decrease in alloy material photoconductivity with increasing alloy content.

• Research Organization: Solar Energy Research Institute, Golden, Colorado 80401
• DOE Contract Number: AC02-83CH10093
• OSTI ID: 6124636
• Journal Information: Appl. Phys. Lett.; (United States), Journal Name: Appl. Phys. Lett.; (United States) Vol. 51:15; ISSN APPLA
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
36 MATERIALS SCIENCE
360603 -- Materials-- Properties
ALLOYS
AMORPHOUS STATE
CARBIDES
CARBON COMPOUNDS
CRYSTAL STRUCTURE
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
GERMANIUM ALLOYS
INFORMATION
INFRARED SPECTRA
MICROSTRUCTURE
NUMERICAL DATA
PHOTOCONDUCTIVITY
PHYSICAL PROPERTIES
SILICON ALLOYS
SILICON CARBIDES
SILICON COMPOUNDS
SPECTRA