High-Quality 4H-SiC Homogeneous Epitaxy via Homemade Horizontal Hot-Wall Reactor

Abstract

In this paper, using a self-developed silicon carbide epitaxial reactor, we obtained high-quality 6-inch epitaxial wafers with doping concentration uniformity less than 2%, thickness uniformity less than 1% and roughness less than 0.2 nm on domestic substrates, which meets the application requirements of high-quality Schottky Barrier Diode (SBD) and Metal–Oxide–Semiconductor Field-Effect Transistor (MOSFET) devices. We found that increasing the carrier gas flow rate can minimize source gas depletion and optimize the doping uniformity of the 6-inch epitaxial wafer from over 5% to less than 2%. Moreover, reducing the C/Si ratio significantly can suppress the “two-dimensional nucleation growth mode” and improve the wafer surface roughness Ra from 1.82 nm to 0.16 nm.