A selective as well as full wafer size graphene sheets layer (GSL) growth on either face of a silicon carbide (4H-SiC and 6H-SiC) semiconductor wafers by its heating in a range of 1500-2000oC in vacuum has been demonstrated by using a pyrolytic graphite case (PGC) as well as a mask (PGM). A uniform GSL and carbon nano walls (CNW) have been confirmed with cross-sectional view the scanning electron microscopy (SEM) and the transmission electron microscopy (TEM) images with and without using a PGC. Raman spectroscopic analytic results are used to distinguise among crystal quality of CNS layers, e.g., CNT, GSL and CNW. Raman spectroscopy results show high quality GSL grown with a negligible minimum disorder-induced phonon mode at 1362 cm-1 (D-band) and a promenantly strong peak for graphite structure-induced photon mode at 1604 cm-1 (G band). The high quality GSL grown by SiC heating technique in vacuum chamber using a PGC with a PGM was realized by creating a second turbulence disturbance free environment aound a heating SiC wafer in the vacuum chamber due to a turbo vacuum pump. A secondary ion mass spectroscopy (SIMS) study confirmed that an oxygen rich layer of about 25 nm thickness remains trapped at the interface CNS layer and SiC wafer to support a proposed CNS layer growth mechanism.