Amorphous-silicon thin-film heterojunction solar cells

Technical Report · Thu Jan 01 04:00:00 EST 1981

DOI:https://doi.org/10.2172/6660788· OSTI ID:6660788

Cretella, M. C.; Gregory, J. A.; Sandstrom, D. B.; Paul, W.

The investigation of amorphous silicon materials at MTSEC has had two major thrusts: (1) to improve the amorphous material, i.e., obtain a low state density in the gap, improve the carrier collection depth and diminish non-radiative recombinations; and (2) to attempt to understand and improve on the limitations of the junction devices while evaluating the amorphous silicon materials. In the first of these efforts, the investigation has continued to examine the modifications to the a-Si(H) network by alloying silicon with other group IVA elements, either in binary or ternary compositions, and/or by replacing the hydrogenation for defect compensation with a combination of hydrogenation and alkylation or hydrogenation and halogenation. The doped junction layers are being examined in an attempt to determine the limiting characteristics of the junctions in solar cell devices of these amorphous materials. Amorphous alloys of Si-Ge, Si-C, Si-Sn were prepared as well as ternary compositions of Si-Ge-C and Si-Sn-C. In addition, Na vapor was added to the gas feed to deposit a-Si(Na, H) films, and to prepare Si-Sn, fluoride was added along with the tin by vapor additions of SnF/sub 4/ to the gas feed. The optical properties of these materials were measured, and structural and compositional information was obtained from the IR vibrational spectra using the scanning electron microscope and from analyses using scanning Auger microscopy. Electrical measurements have included the dark conductivity and the photo conductivity under room fluorescent light and at AM1 conditions. With alloys that displayed promising photoconductive properties n-i-p devices were prepared to assess the solar cell properties. Details are presented. (WHK)

• Research Organization: Mobil Tyco Solar Energy Corp., Waltham, MA (USA)
• DOE Contract Number: AC02-77CH00178
• OSTI ID: 6660788
• Report Number(s): SERI/PR-9056-1-T1
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
360603 -- Materials-- Properties
ABSORPTIVITY
ALLOYS
AMORPHOUS STATE
CARBON COMPOUNDS
DEPOSITION
DIRECT ENERGY CONVERTERS
ELECTRIC CONDUCTIVITY
ELECTRIC DISCHARGES
ELECTRICAL PROPERTIES
ELEMENTS
ENERGY GAP
EQUIPMENT
FABRICATION
FILMS
GERMANIUM ALLOYS
GLOW DISCHARGES
OPTICAL PROPERTIES
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PLATING
RECOMBINATION
SEMIMETALS
SILICON
SILICON ALLOYS
SILICON SOLAR CELLS
SODIUM ADDITIONS
SODIUM ALLOYS
SOLAR CELLS
SOLAR EQUIPMENT
SPECTRAL RESPONSE
SURFACE COATING
TIN ALLOYS
VAPOR PLATING