>Effect of hydrogen flow on growth of 3C-SiC heteroepitaxial layers on Si(111) substrates
3C-SiC thin films of preferential orientation along with Si(111) substrates were obtained using home-made horizontal LPCVD with different H2 flow rate ranging from15 to 30 slm.
High H2 flow rate will inhibit the out-diffusion of silicon atoms from silicon substrates effectively. Transformation and the mechanism of void formation are discussed based on our model.
The variation of growth rate and n-type doping with increasing H2 flow rate is researched and the influencing mechanism is discussed.
3C-SiC thin films were grown on Si(111) substrates at 1250 °C by horizontal low pressure chemical vapor deposition (LPCVD). We performed an exhaustive study on the effect of H2flow rate on the crystalline quality, surface morphologies, growth rate, n-type doping of 3C-SiC thin films and the voids at the interface. The films show epitaxial nature with high crystal quality and surface morphology increase obviously with increasing H2 flow rate. The growth rate and n-type doping are also dependent on H2 flow rate. The properties of the voids at the interface are discussed based on the cross-sectional scanning electron microscope characterization. Transformation of voids with increasing H2 flow rate are attributed to higher 3C-SiC film growth rate and H2 etching rate. The mechanism of void formation is discussed based on our model, too. The results demonstrate that H2 flow rate plays a very important role in the heteroepitaxial growth of 3C-SiC films.