Studies of hydrogenated amorphous silicon
Abstract
This report discusses the results of probing the defect structure and bonding of hydrogenated amorphous silicon films using both nuclear magnetic resonance (NMR) and electron spin resonance (ESR). The doping efficiency of boron in a-Si:H was found to be less than 1%, with 90% of the boron in a threefold coordinated state. On the other hand, phosphorus NMR chemical shift measurements yielded a ration of threefold to fourfold P sites of roughly 4 to 1. Various resonance lines were observed in heavily boron- and phosphorus-doped films and a-SiC:H alloys. These lines were attributed to band tail states on twofold coordinated silicon. In a-SiC:H films, a strong resonance was attributed to dangling bonds on carbon atoms. ESR measurements on low-pressure chemical-vapor-deposited (LPCVD) a-Si:H were performed on samples. The defect density in the bulk of the films was 10/sup 17//cc with a factor of 3 increase at the surface of the sample. The ESR spectrum of LPCVD-prepared films was not affected by prolonged exposure to strong light. Microcrystalline silicon samples were also examined. The phosphorus-doped films showed a strong signal from the crystalline material and no resonance from the amorphous matrix. This shows that phosphorus is incorporated in the crystals and ismore »
- Authors:
- Publication Date:
- Research Org.:
- Naval Research Lab. (NRL), Washington, DC (United States)
- OSTI Identifier:
- 6781663
- Report Number(s):
- SERI/STR-211-2393
ON: DE84013038
- DOE Contract Number:
- AC02-83CH10093
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: Portions are illegible in microfiche products. Original copy available until stock is exhausted
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; SILICON; CRYSTAL DEFECTS; ELECTRON SPIN RESONANCE; NUCLEAR MAGNETIC RESONANCE; AMORPHOUS STATE; BORON; CHEMICAL VAPOR DEPOSITION; CRYSTAL DOPING; HYDROGEN ADDITIONS; PHOSPHORUS; CHEMICAL COATING; CRYSTAL STRUCTURE; DEPOSITION; ELEMENTS; MAGNETIC RESONANCE; NONMETALS; RESONANCE; SEMIMETALS; SURFACE COATING; SOLAR ENERGY; PHOTOVOLTAIC; 140501* - Solar Energy Conversion- Photovoltaic Conversion; 360603 - Materials- Properties
Citation Formats
Bishop, S G, and Carlos, W E. Studies of hydrogenated amorphous silicon. United States: N. p., 1984.
Web. doi:10.2172/6781663.
Bishop, S G, & Carlos, W E. Studies of hydrogenated amorphous silicon. United States. https://doi.org/10.2172/6781663
Bishop, S G, and Carlos, W E. 1984.
"Studies of hydrogenated amorphous silicon". United States. https://doi.org/10.2172/6781663. https://www.osti.gov/servlets/purl/6781663.
@article{osti_6781663,
title = {Studies of hydrogenated amorphous silicon},
author = {Bishop, S G and Carlos, W E},
abstractNote = {This report discusses the results of probing the defect structure and bonding of hydrogenated amorphous silicon films using both nuclear magnetic resonance (NMR) and electron spin resonance (ESR). The doping efficiency of boron in a-Si:H was found to be less than 1%, with 90% of the boron in a threefold coordinated state. On the other hand, phosphorus NMR chemical shift measurements yielded a ration of threefold to fourfold P sites of roughly 4 to 1. Various resonance lines were observed in heavily boron- and phosphorus-doped films and a-SiC:H alloys. These lines were attributed to band tail states on twofold coordinated silicon. In a-SiC:H films, a strong resonance was attributed to dangling bonds on carbon atoms. ESR measurements on low-pressure chemical-vapor-deposited (LPCVD) a-Si:H were performed on samples. The defect density in the bulk of the films was 10/sup 17//cc with a factor of 3 increase at the surface of the sample. The ESR spectrum of LPCVD-prepared films was not affected by prolonged exposure to strong light. Microcrystalline silicon samples were also examined. The phosphorus-doped films showed a strong signal from the crystalline material and no resonance from the amorphous matrix. This shows that phosphorus is incorporated in the crystals and is active as a dopant. No signal was recorded from the boron-doped films.},
doi = {10.2172/6781663},
url = {https://www.osti.gov/biblio/6781663},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jul 01 00:00:00 EDT 1984},
month = {Sun Jul 01 00:00:00 EDT 1984}
}