AFM investigation of interface step structures on PVT-grown (0 0 0 1)Si 6H–SiC crystals

Growth of 6H–SIC crystals along the [011¯5<

“…To solve this problem, SiC crystals should be grown without a neighboring polycrystalline rim [20]. In principle polytype information is transmitted perpendicular to the c-axis, parallel to the direction of steps propagation [13]. We believe that this is also true in our case.…”

“…For further details about this topic it is referred to Ref. [13]. More interestingly, the ð0 11 5Þ facet was obtained on the cylinder as determined by back scattering Laue measurements (Fig.…”

“…This pattern could be used as reference for identification of the ð0 11 5Þ face. ð0 11 5Þ is less stable as the former was found to be stable in a high range of thermal profiles [13,15]. It was shown that when applying a convex thermal field, the size of the (0 0 0 1) facet was reduced in respect to the non-faceted area of the monocrystalline area but this facet was almost always present.…”

“…For further details about the stability of a facet in respect to the thermal field it is referred to Ref. [13]. In addition, it was shown that the ð0 11 1Þ and the ð0 11 2Þ facets are formed by a superposition of different small facets having the type ð0 11nÞ; n is an integer [6,14].…”

“…The terrace width L is about 5 mmoLo20 mm and the step height h415 nm: During growth of undoped 6H-SiC crystals along the [0 0 0 1] direction, step bunching occurs if the surface is inclined in reference to the (0 0 0 1) plane [13] whereas step bunching occurs within the flat faceted area during growth along the ½0 11 5 direction. This is another indication that the ð0 11 5Þ facet is the second stable after the conventional (0 0 0 1).…”