Materials Science Forum, Vol.457-460, 521-524, 2004
Crystallographic defects under surface morphological defects of 4H-SiC homoepitaxial films
Transmission electron microscopy (TEM) was applied to characterize the crystallographic defects associated with "device-killing" surface morphological defects of 4H-SiC homoepitaxial films. Typical surface defects exhibit elongated shape along the off-cut direction [11-20] and are classified into "comet", "triangular defect" and "carrot" according to their morphological features. The "comet" is accompanied by 3C-SiC of zinc blende structure. The "triangular defect" and "carrot" are associated with stacking faults on the (0001) plane. From observations of the samples in which their homoepitaxial films had been partially or completely removed prior to the TEM sample preparation, it was suggested that the defects were not directly inherited from the substrate.
Keywords:4H-SiC;homoepitaxy;surface morphological defect;crystallographic defect;transmission electron microscopy (TEM)