Archive for the ‘Uncategorized’ Category

Bulk growth of single crystal silicon carbide

Friday, October 16th, 2009

06_09Silicon carbide (SiC) is a promising wide bandgap semiconductor material particularly suitable for future high power devices operable at high temperatures (>200 °C), at high frequencies, and in harsh environments (chemical and radiation) due to its unique physical and crystallographic properties. The absence of SiC liquid phase, under easily achievable growth conditions of pressure and temperature has created unique challenges for crystal growers.

This paper reviews the basics of bulk growth processes, including source sublimation, mass transport of the Si and C species to the growing seed and crystallization. The growth process is shown to be a self-congruent phenomenon where the mass transport of the vapor species and the heat dissipation at the surface of phase transformation are interrelated. This process results in reduction of the growth velocity as a function of crystal thickness. Major mechanisms of defect generation in the grown crystal are discussed.

Silicon carbide transport during carbothermic reduction of SiO2

Wednesday, October 7th, 2009

Mass-transfer processes during the high-temperature carbothermic reduction of silicon dioxide have been studied using thermodynamic modeling. The chemical vapor transport of silicon carbide has been investigated using SiO2 + xSiC mixtures—major reaction products in the SiO2-C system—as examples. Thermodynamic modeling results indicate that the vapor transport of silicon carbide is possible at temperatures from 1300 to 1500°C, and that the major gaseous species involved are Si and CO. Vapor transport processes have been studied experimentally. It is shown that the thermal reaction between carbon monoxide and silicon leads not only to direct conversion of silicon particles to silicon carbide but also to the growth of silicon oxycarbide fibers. The synthesized material has been characterized by x-ray diffraction and high-resolution optical microscopy.

http://www.springerlink.com/content/c1750pk110330460/

New Web Site Design

Thursday, September 24th, 2009

Please pardon the current site’s appearance.  We are extremely busy at the moment and will have more information up as we have the time to post it.  Thank you very much.

S.M.