Progress in Cold-Wall Epitaxy for 4H-SiC High-Power Devices
Cold-wall vapor phase epitaxy was utilized to grow uniform 4H-SiC layers with abrupt doping interfaces on 4o off-axis substrates. Concentrations of Al were reduced roughly 200x after 0.1 μm of epitaxy after trimethylaluminum flow was stopped. Thickness uniformity of cold-wall epitaxy across 3” wafers was as good as 3.2%. Minority carrier diffusion lengths of 27 μm-thick 4H-SiC epitaxy grown in a cold-wall design were as high as 58 μm.
N. Wright, C.M. Johnson, K. Vassilevski, I. Nikitina and A. Horsfall
L.B. Rowland et al., "Progress in Cold-Wall Epitaxy for 4H-SiC High-Power Devices", Materials Science Forum, Vols. 556-557, pp. 141-144, 2007