Observations and analyses of microstructural defects for chemical vapour deposited ?-SiC by transmission electron microscopy

Abstract

A transparent silicon carbide was grown by a cold-wall chemical vapour deposition (CVD) system using CH3SiCl3 and hydrogen gas mixtures on to a graphite substrate. Transmission electron microscopy was used to observe microstructural defects of CVD Β-SiC, usingg.b = 0,±1/3 and theg.R F = integer criterion, quantitative information on defects can be obtained. Theb was identified as 1/6 [11¯2] for Shockley partial dislocations andR F as 1/3[¯111], 1/3 [1¯11], 1/3 [11¯1] for stacking faults. Twin planes were identified as (11¯1), (¯11¯1) in this study. Stacking faults and twins always existed on {111}. Subgrains were surrounded by dislocation networks and full of microtwins. Other defects, such as dislocation loops and dislocation dipoles, were also observed.