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Periodic patterns of silicon carbide (SiC) micropillars of 18 μm in length and 2 μm in diameter with a hexagonal morphology and an areal number density of micropillars of 6 × 104 mm−2 were fabricated from a mixture of two different polycarbosilane ceramic precursors. The polycarbosilanes (PCS) were molded into polydimethylsiloxane (PDMS) micromolds processed from a silicon wafer master. After cross‐linking between 200° and 400°C, debonding from the elastomeric PDMS mold yielded freestanding structures of PCS micropillars. Due to the low stiffness of cross‐linked PCS (E∼2.5 GPa), surface adhesion forces might result in the deformation of the micropillars into ordered domains. The PCS micropillar arrays were pyrolyzed in inert atmosphere at 900° and 1500°C to yield amorphous and nanocrystalline SiC (β‐SiC) with crystallite sizes in the range of tenths of micrometers, respectively. The formation of domains due to instability of micropillars with a high aspect ratio might be of specific interest for electrical engineering and catalytic applications.

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The method to attach seed to crucible lid as well as seed quality is very important for obtaining high quality crystals. Therefore, modified seeding method was developed for improving adhesive layer between seed and graphite crucible lid. SiC single crystal grown with modified seeding method definitely exhibited lower micropipe density (MPD) and lower full width at half maximum (FWHM) values comparing with values from conventional seeding method. Etch pit density of SiC crystal was successfully decreased with using the modified seeding method.

Vanadium-doped SiC crystals have been grown by using a porous graphite inner crucible filled with vanadium carbide (VC) and by using a porous graphite plate and SiC + VC powders, respectively. Semi-insulating SiC crystals were grown onto the 6H-SiC seed crystals by PVT (Physical Vapor Transport) method. The grown crystals were indicated to be 6H-SiC polytype by XRD. As result of SIMS analysis, vanadium-rich precipitates were observed when the vanadium concentration was relatively higher than the maximum solubility of vanadium (3-5 × 10) in vanadium-doped SiC crystals, which resulted in degradation of crystal quality. Key words