In this work, the growth of high quality 3C-SiC films on Si substrates grown by a hot-wall chemical vapor deposition (CVD) reactor is presented. An increased crystal quality means a reduced crystallographic defect density affecting 3C-SiC films which can be achieved by reducing the growth rate during 3C-SiC heteroepitaxy. In particular, the micro-twin density was observed to decrease with decreasing growth rate allowing for the reduction of theboth the rocking curve and transverse optical Raman mode peak width. Si substrates, both of on-and off-axis orientation, are considered with improvement in crystal quality observed when off-axis substrates are used. Finally, stacking faults and microtwins at the SiC/SiO2 interface are seen to cause non-uniformity in the oxide layer due to the different oxidation rate observed.