Type
Text
Type
Thesis
Advisor
Dudley, Michael | Venkatesh, T.A.. | Raghothamachar, Balaji
Date
2014-12-01
Keywords
Materials Science
Department
Department of Materials Science and Engineering.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76289
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Boron phosphide (BP) with its high capture cross section for thermal neutrons is potentially a great candidate material for neutron detectors. Bulk BP substrates are not readily available for developing detector devices therefor heteroepitaxial growth by CVD on commercially available substrates are currently being explored. The quality of BP films growth on commercial Si substrates is too poor for use in detector applications. In this thesis, we explore various substrates for suitability for BP heteroepitaxy by characterizing the crystalline quality of the epilayers grown under various growth conditions. Substrate materials used in this study include on-axis c-plane 6H-SiC, off-axis c-plane 4H-SiC with vicinal steps, Si substrates with 3C-SiC buffer layer and sapphire substrates with AlN buffer layers. Using SWBXT in combination with SEM and optical microscopy, we have compared the quality of BP grown on different substrates and the optimum growth condition and suitable substrates have been proposed. Also, the BP film growth mechanism and twin defect origination mechanism are explained based on experimental and theoretical studies. Based on experimental results, off-axis substrates could reduce the possibility of the presence of BP twin structure, but not sufficiently; the growth of BP film on Si substrates by using 3C-SiC as a buffer layer has been exhibited as a preferable substrate, where no BP twin is revealed; for the growth of BP films on AlN/Sapphire substrates, poor quality of BP films and unknown materials are observed. Sapphire is widely used as substrates for GaN-based LEDs for solid state applications and other related industries. High transparency and low defect density are desirable properties of sapphire wafers for these applications. However, undesirable defects in sapphire wafers hamper their development. Various characterization techniques are used to examine the quality of sapphire. In this study, by comparing conoscopic patterns with X-ray Topographs, actual defect distributions have been correlated with conoscopic patterns and the reliability of conoscopic results for evaluating the quality of sapphire wafers has been studied,48 pages
Recommended Citation
Chen, Ruifen, "Properties of Boron Phosphide Films Grown on Different Substrates and Conoscopic Study of Sapphire" (2014). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2215.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2215