Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Klahold, W. M.*; Devaty, R. P.*; Choyke, W. J.*; 河原 洸太朗*; 木本 恒暢*; 大島 武
Materials Science Forum, 778-780, p.273 - 276, 2014/02
Ultra-pure n-type (810 cm), 99 m thick epitaxial layers of hexagonal (4H) silicon carbide (SiC) were irradiated with electrons either at 170 keV with a fluence of 510 cm or at 1 MeV with a fluence of 110 cm in various geometries. Low temperature photoluminescence (LTPL) spectra and microwave photoconductance (PCD) lifetime measurements were carried out for all samples before and after annealing in argon in free standing mode or on a POCO carbon (Poco Graphite, Inc.) platform, every 50 C from 1100 C to 1500 C. However, no improvement in carrier lifetime was observed although previous studies reported that carbon diffused into SiC during high temperature treatment improves carrier lifetime. The result obtained in this study suggests that simple carbon diffusion model cannot be applied and more study is required to understand the injection of carbon interstitials into the SiC lattice.
Son, N. T.*; Trinh, X. T.*; Lvile, L. S.*; Svensson, B. G.*; 河原 洸太朗*; 須田 淳*; 木本 恒暢*; 梅田 享英*; 磯谷 順一*; 牧野 高紘; et al.
Physical Review Letters, 109(18), p.187603_1 - 187603_5, 2012/11
被引用回数:199 パーセンタイル:97.98(Physics, Multidisciplinary)Nitrogen-doped n-type 4H-Silicon carbide (SiC) epitaxial layers were irradiated with electrons at 250 keV. Carbon vacancy (V) signals at both the h and k sites were studied using photoexitation Electron Paramagnetic Resonance (photo-EPR) and Deep Level Transient Spectroscopy (DLTS). As a result, double negative charge states of V, showing its negative-U system were revealed. By the direct correlation between EPR and DLTS data, it was concluded that Z is V at h site and Z is V at k site. In addition, we concluded that EH is a single donor level of V.