Influence of C/Si ratio on the 4H-SiC (0001) epitaxial growth and a keynote for high-rate growth

We have carried out the epitaxial growth of 4H-SiC with the various flow rates of SiH4 and C3H8, and have achieved the growth rates as high as 100 mum/h with good crystalline quality even at the usual CVD growth temperatures around 1600 degreesC. We found that the C/Si ratio influences strongly on the surface morphology of epilayers, and that the window of the C/Si ratio bringing about mirror-like surfaces becomes narrow with the increase of growth rate. We a] so found that the rough surfaces can be classified into four types and that the change from mirror to rough with the growth conditions is drastic like a phase change. We will give the keynote to achieve the high-rate growth of over 100 mum/h without the degradation of surface morphologies.