Heteroepitaxial growth of 3C-SiC on patterned Si substrates by low pressure chemical vapor deposition （LPCVD） has been investigated to improve the crystal quality of 3C-SiC films. Si substrates were patterned with parallel lines,1 to 10μm wide and spaced 1 to 10μm apart,which was carried out by photolithography and reactive ion etching. Growth behavior on the patterned substrates was systematically studied by scanning electron microscopy （SEM）. An airgap structure and a spherical shape were formed on the patterned Si substrates with different dimensions. The air gap formed after coalescence reduced the stress in the 3C-SiC films, solving the wafer warp and making it possible to grow thicker films. XRD patterns indicated that the films grown on the maskless patterned Si substrates were mainly composed of crystal planes with （111） orientation.
