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Title: Effects of varying oxygen partial pressre on molten silicon: ceramic substrate interactions, final report

Abstract

The objective of the contract is to investigate the interaction of molten silicon with various die and container candidate materials under varying oxygen partial pressures. This has been done by making silicon sessile drop contact angle measurements on the candidate materials to determine the degree to which silicon wets these substances, and subsequently sectioning the post-sessile drop experiment samples and taking photomicrographs of the silicon-substrate interface to observe the degree of surface dissolution and degradation. Several different materials supplied by JPL have been investigated in this manner, i.e., hot pressed silicon nitride (from both Kawecki Berylco, Inc. (KBI) and AVCO), CNTD silicon nitride coated on hot pressed silicon nitride (Chemetal-Eagle Picher), CVD silicon carbide coated on graphite (Ultracarbon), and ..cap omega.. Sialon (Battelle). Results are described. The oxygen concentrations in the EFG silicon ribbon furnace at Mobil Tyco Solar Energy Corp., Waltham, Massachusetts, and in the JPL silicon sessile drop furnace at Pasadena, California, were measured using the portable thoria-yttria solid solution electrolyte oxygen sensor constructed at UMR for this purpose. Oxygen partial pressures of 10/sup -7/ and 10/sup -8/ atm. were obtained for the Mobil Tyco and JPL facilities, respectively.

Authors:
; ;
Publication Date:
Research Org.:
Missouri Univ., Rolla (USA). Dept. of Ceramic Engineering
OSTI Identifier:
5085141
Report Number(s):
DOE/JPL/955415-2
DOE Contract Number:
NAS-7-100-955415
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; CERAMICS; COMPATIBILITY; SILICON; CRYSTAL GROWTH; CONTAINERS; CONTROLLED ATMOSPHERES; DIES; ELECTRON MICROSCOPY; MATERIALS; MATERIALS TESTING; OXYGEN; SILICON CARBIDES; SILICON NITRIDES; SUBSTRATES; VAPOR PRESSURE; WETTABILITY; ATMOSPHERES; CARBIDES; CARBON COMPOUNDS; ELEMENTS; MICROSCOPY; NITRIDES; NITROGEN COMPOUNDS; NONMETALS; PHYSICAL PROPERTIES; PNICTIDES; SEMIMETALS; SILICON COMPOUNDS; TESTING; THERMODYNAMIC PROPERTIES; 140501* - Solar Energy Conversion- Photovoltaic Conversion; 360601 - Other Materials- Preparation & Manufacture

Citation Formats

Ownby, P.D., Romero, H.V., and Barsoum, M.W. Effects of varying oxygen partial pressre on molten silicon: ceramic substrate interactions, final report. United States: N. p., 1980. Web. doi:10.2172/5085141.
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Ownby, P.D., Romero, H.V., & Barsoum, M.W. Effects of varying oxygen partial pressre on molten silicon: ceramic substrate interactions, final report. United States. doi:10.2172/5085141.
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Ownby, P.D., Romero, H.V., and Barsoum, M.W. Tue . "Effects of varying oxygen partial pressre on molten silicon: ceramic substrate interactions, final report". United States. doi:10.2172/5085141. https://www.osti.gov/servlets/purl/5085141.
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@article{osti_5085141,
title = {Effects of varying oxygen partial pressre on molten silicon: ceramic substrate interactions, final report},
author = {Ownby, P.D. and Romero, H.V. and Barsoum, M.W.},
abstractNote = {The objective of the contract is to investigate the interaction of molten silicon with various die and container candidate materials under varying oxygen partial pressures. This has been done by making silicon sessile drop contact angle measurements on the candidate materials to determine the degree to which silicon wets these substances, and subsequently sectioning the post-sessile drop experiment samples and taking photomicrographs of the silicon-substrate interface to observe the degree of surface dissolution and degradation. Several different materials supplied by JPL have been investigated in this manner, i.e., hot pressed silicon nitride (from both Kawecki Berylco, Inc. (KBI) and AVCO), CNTD silicon nitride coated on hot pressed silicon nitride (Chemetal-Eagle Picher), CVD silicon carbide coated on graphite (Ultracarbon), and ..cap omega.. Sialon (Battelle). Results are described. The oxygen concentrations in the EFG silicon ribbon furnace at Mobil Tyco Solar Energy Corp., Waltham, Massachusetts, and in the JPL silicon sessile drop furnace at Pasadena, California, were measured using the portable thoria-yttria solid solution electrolyte oxygen sensor constructed at UMR for this purpose. Oxygen partial pressures of 10/sup -7/ and 10/sup -8/ atm. were obtained for the Mobil Tyco and JPL facilities, respectively.},
doi = {10.2172/5085141},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Apr 01 00:00:00 EST 1980},
month = {Tue Apr 01 00:00:00 EST 1980}
}
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Technical Report:
View Technical Report (6.01 MB)
DOI:  10.2172/5085141
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