Polytype transformations in SiC‐epitaxial layers: The color cathodoluminescence‐sem studies

Abstract

Summary:The polytype transformation in SiC-epitaxial layers grown by the sublimation "sandwich method" have been studied by means of a real color SEM cathodoluminescence (CL) technique. The variation of polytypes grown on 6H-, 4H-, 15R-, and 21R-polytype substrates is demonstrated. Different spectral composition of local CL emission is observed on smooth and profiled substrate surfaces. The double polytype transformation effect was fixed. The nature of the polytype transformation in S i c epitaxial layers is discussed.

Color cathodoluminescence‐scanning electron microscopy study of the 4H‐SiC heteroepitaxial layers grown by sublimation “sandwich method”

“…Earlier, it was shown (Vodakov et al 1992) that the epitaxial growth on projected areas proceeds independently and the presence of specific structural defects on the growing surface influenced the growth rate. We used this method of artificial local surface singularization (ALSS) for an investigation of the SiC polytype transformation during growth process (Saparin et al 1994). Polytype identification of the epitaxial layers has been realized by means of luminescence spectra.…”

“…Earlier it was shown (Saparin et al 1994) that the transformation probability of polytypes is higher for projected areas in comparison with other parts of the substrate. We observed the same effect for grown heteroepitaxial 4H layers at very low growth rate or supersaturations.…”

Color cathodoluminescence display in the scanning electron microscope of deep relief surfaces

“…The polytype transformations of the SiC single crystal growth process are available at all times (Saparin et al 1994). There is also a tendency to alternate the sequences of different polytype layers (Saparin et al 1996).…”

“…Silicon carbide (SiC) has a lot of stoichiometric modifications and the polytypes which caused the CL emission to cover all visual intervals of light spectrum. The polytype trans-formations of the SiC single crystal growth process are available at all times (Saparin et al 1994). There is also a tendency to alternate the sequences of different polytype layers (Saparin et al 1996).…”

Computer modeling of three‐dimensional reconstruction algorithm of cathodoluminescence material properties, analysis of errors, and optimization of variable parameters

“…The investigation of different samples by color cathodoluminescence scanning electron microscopy (CCL-SEM) mode (Saparin and Obyden 1988;1993) frequently requires information from luminescent layers located under specimen surface for the detection of the volume defect distribution and its size and shape. As a rule, such studies are carried out by cutting slices or layer by layer etching, or by sample polishing (Marshallinger 1998, Saparin et al 1994. The three-dimensional (3-D) reconstruction technique of luminescence material properties (Saparin et al 1996) permits the reconstruction of luminescence properties of subsurface layers without their destruction.…”