A Study of CVD Growth Parameters to Fill 50-μm-Deep 4H-SiC Trenches

By inspecting the CVD growth parameters, such as the flow rates of HCl and H2 carrier gases, the pressure and the C/Si ratio, the trench filling in a high-rate mode with a high growth rate on the bottom and a relatively low growth rate on the mesa top was carried out. 4H-SiC trenches with the depths of 48 and 55 μm have been completely filled at the rates of 6.2 and 5.5 μm/h, respectively.