The characterization of aluminum nitride-silicon carbide alloy crystals on silicon carbide substrates
EMSL Project ID
9609
Abstract
AlN-SiC alloy crystals, with outstanding physical and electronic properties, are excellent for bandgap engineering and promising as substrates superior to either AlN or SiC. They are prepared on off-axis Si-face 6H-SiC (0001) substrate by sublimation-recondensation method from a mixture of AlN and SiC powders at 1860-1990 °C in a N2 atmosphere. The bonding configuration of each element in AlN-SiC is of great interest, since it affects the homogeneity and stoichiometry of the alloy crystals, which are determined by the growth temperature. X-ray photoelectron spectroscopy (XPS) is an ideal characterization method for analyzing the bonding of AlN-SiC alloys. In addition, the homogeneity of elemental distribution throughout the alloy crystals is essential. Secondary ion mass spectrometry (SIMS) can measure the lateral distribution of elements by depth profiling to confirm the uniformity of the alloy crystals. Transmission electron microscopy (TEM) is a powerful tool to study the alloy crystal structures and the crystal/substrate interface properties. The x-ray EDS microanalysis system can detect the elements involved and provide both qualitative and quantitative elemental analyses. We plan to grow AlN-SiC alloy crystals on off-axis 6H-SiC substrate at different temperatures and N2 pressures. Then SIMS is performed to determine the change of the composition and elemental distribution of the alloy crystals with the growth temperature. TEM can provide the basic crystallographic information and confirm the SIMS results. XPS is carried out to measure if the change is caused by the elemental bonding difference in the AlN-SiC alloys.
Project Details
Project type
Exploratory Research
Start Date
2004-08-02
End Date
2006-08-31
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Gu Z, JH Edgar, CM Wang, and D Coffey. 2006. "Thermal Oxidation of Aluminum Nitride Powder ." Journal of the American Ceramic Society 89(7):2167?2171.