Evaluation of Unintentionally Doped Impurities in Silicon Carbide Substrates Using Neutron Activation Analysis
Impurity atoms in a high-purity semi-insulating 4H-SiC substrate fabricated by sublimation and an n-type 3C-SiC substrate fabricated by Chemical Vapor Deposition (CVD) were evaluated by neutron activation analysis. Cr, Fe, Zn, As, Br, Mo, Sb, Eu, Yb, Hf, Ta, W and Au atoms were detected in the 4H-SiC fabricated by sublimation. In the 3C-SiC fabricated by CVD, Cr, Zn, As, Br, Mo, Sb, La Sm and Hf atoms were found. The concentration of these atoms tends to decrease with increasing atomic number.
N. Wright, C.M. Johnson, K. Vassilevski, I. Nikitina and A. Horsfall
T. Ohshima et al., "Evaluation of Unintentionally Doped Impurities in Silicon Carbide Substrates Using Neutron Activation Analysis", Materials Science Forum, Vols. 556-557, pp. 457-460, 2007