Epitaxial Growth of SiC Films on 4H-SiC Substrate by High-Frequency Induction-Heated Halide Chemical Vapor Deposition

Abstract

SiC epitaxial wafers offer enormous potential for a wide range of telecom technologies due to their excellent properties. The experimental process was simulated by software, and the contour of gas flow velocity and raw material mass fraction inside the chamber were obtained. SiC films were epitaxially grown on 4H-SiC single crystalline substrates at different temperatures for one batch, using SiCl4, CH4, and H2 as precursors. With increasing temperature, the crystal phase changed from 4H-SiC at 1773 K to a mixture of 4H- and 3C-SiC, and then a mixture of 3C-SiC and graphite at higher than 1923 K. The film was mainly (004)-oriented 4H-SiC and (111)-oriented 3C-SiC.

Silicon Carbide Thin Film Technologies: Recent Advances in Processing, Properties, and Applications - Part I Thermal and Plasma CVD

“…57 4. Hexagonal 4H-SiC: Few reports have been published recently on CVD of hexagonal (4H-SiC) polytype thin films, 36,37,40,51,57,58 a fact which could be attributed to their already well-established properties and widespread use in a variety of proven technological applications, as discussed above. The primary focus of ongoing research efforts into CVD 4H-SiC thin films is on enhancing epitaxy and reducing defects in well-established 4°off-axis 4H-SiC substrates.…”

“…• Alternatively, R. Tu et al 37 deposited SiC films on 4H-SiC single crystalline substrates at various temperatures using SiCl and CH 4 as Si and C precursors, respectively. They reported that the crystalline phase evolved with higher substrate temperature: from 4H-SiC at 1477 °C-1527 °C to a mixed 4H-and 3C-SiC phase at 1577 °C, and finally a blend of 3C-SiC and graphite above 1650 °C.…”

“…Single Source Precursors: In terms of source precursors, thermal and PE-CVD predominantly use either inorganic perhydridosilanes or halosilanes as Si sources and hydrocarbons as C sources for the formation of SiCx. Silane (SiH4), 9,18,31,36,38,40,42,44,45,51 trichlorosilane (SiHCl3 or TCS), 38,57,58,60,61 and tetrachlorosilane (SiCl4) 37,47,[53][54][55][56][57] continue to be the most preferred Si precursors, while methane, acetylene, ethylene, and propane are the hydrocarbons most employed as C sources. 9,18,31,[36][37][38]40,42,44,45,47,51,[53][54][55][57][58][59] However, the universally established use of perhydridosilanes or halosilanes presents significant challenges that limit applicability in many emerging SiC applications which employ thermally, chemically, and/or electrically fragile substrates.…”

“…Silane (SiH4), 9,18,31,36,38,40,42,44,45,51 trichlorosilane (SiHCl3 or TCS), 38,57,58,60,61 and tetrachlorosilane (SiCl4) 37,47,[53][54][55][56][57] continue to be the most preferred Si precursors, while methane, acetylene, ethylene, and propane are the hydrocarbons most employed as C sources. 9,18,31,[36][37][38]40,42,44,45,47,51,[53][54][55][57][58][59] However, the universally established use of perhydridosilanes or halosilanes presents significant challenges that limit applicability in many emerging SiC applications which employ thermally, chemically, and/or electrically fragile substrates. As mentioned above, CVD SiC from perhydridosilanes or halosilanes necessitates significantly higher decomposition temperatures to yield SiC films with the target properties.…”

The Optimizing Effect of Nitrogen Flow Ratio on the Homoepitaxial Growth of 4H-SiC Layers

“…Compared to other growth methods, the CVD method offers precise control over the thickness, impurity doping, and uniformity (note uniformity is defined by standard deviation/mean value) of the epitaxial layer. As a result, the 4H-SiC homoepitaxial layer obtained through this method has a higher quality and can be directly used to fabricate SiC devices [12]. In order to solve the polytype mixing problem, a proposed solution is epitaxial growth on the SiC substrate using step-flow growth at a specific angle [4].…”