Cathodoluminescence from Polytype Layers in Silicon Carbide
Historical Background
*Wide Indirect Bandgap SiC radiative recombination mechanisms are complex & phonon participation required
Edge Topograph Polytype Model J59 central 5270 reflection 15R+6H+LPP(146H/438R)+1DD(300?m) SEM micrograph Cathodoluminescence crystal morphology polytype/disorder interface
Experimental Techniques
XRDT & CL
Polytype Layers & SEM-CL
Polytype model J77 6H+4H+LPP/1DD+6H
J57 model 6H+15R+1DD(60?m)+4H
Locating CL
Long period polytypes (LPP’s)6
Summary SEM-CL, observed along silicon carbide crystal edges, is reported from regions containing defects & one-dimensionally (1DD) disordered layers. A qualitative description of the location of these features, the common 6H, 15R & 4H and long period polytypes (LPP’s) is possible using SRS XRDT as a comparative technique. Ordered 6H, 4H polytypes display CL. CL data is non quantitative.