Thin crystalline 3C-SiC layer growth through carbonization of differently oriented Si substrates

Abstract

The growth of thin cubic silicon carbide (3C-SiC) buffer layers in an horizontal hot-wall chemical vapor deposition reactor, through the carbonization of differently oriented Si surfaces, is presented. A qualitative and quantitative study has been performed on statistical parameters related to voids due to the buffer layer growth on the different substrate orientations emphasizing shape, size, and density as a function of the substrate orientation. Variation in the void parameters can be attributed to the atomic packing density related to the substrate orientations, which were (100) Si, (111) Si, and (110) Si in this study. Scanning electron microscopy and transmission electron microscopy were performed to analyze the surface and the crystalline quality of the 3C-SiC films grown and, eventually, an empirical model for the carbonization of Si surfaces formulated. Large platens characterize the 3C-SiC films with shapes related to the orientations of the substrate. These platens derive from the two-dimensional growth of different SiC islands which enlarge during the process due to the continuous reaction between Si and C atoms. The interior part of platens was characterized by the presence of a pure crystalline material with the presence of small tilts affecting some grains in the 3C-SiC layer in order to relief the stress generated with the substrate.

Diamond as substrate for 3C‐SiC growth: A TEM study

“…Tentatively, the carbon probably out-diffuses, from the diamond substrate to the SiC buffer layer, to the first nucleated crystals at the expense of the nucleation of new ones. To make a comparison with other systems, other authors evidenced the formation of etch pits growing SiC on Si and these etch pits increase the dimensions at longer growth times [12]. As C-atoms are smaller than Si ones, similar behavior can be expected in the present case and faster process could avoid the creation of the etch pits as well as lower V-L-S growth temperatures.…”

“…2 at the <110> zone axis, containing a cross-sectional view of the SiC/diamond interface and revealing a strong roughness in addition to defects. Since such rough interface is not characteristic of the used diamond substrate (R a < 30 nm), it is presumably due to the growth process, as it looks like the Si out-diffusion induced etch pits often observed in the Si substrate after a carbonization step before 3C-SiC heteroepitaxy [11,12]. The triangular shape of the steps are facetted in the ½11 1 and ½1 11 directions and they are filled with SiC, but this does not exclude the fact that some C out-diffusion occured.…”

A Facile Method for Heteroepitaxial Growth of Homogeneous 3C-SiC Thin Films on Both Surfaces of Suspended Si Wafer by Conventional Chemical Vapor Deposition

“…Interface voids often emerge in the growth of 3C-SiC on Si substrate. 17 This phenomenon is associated with growth process; process temperature, 18 carbonization ramp 19 and experimental parameters 20 are factors to influence the interface void inhibition. When growth is performed at low pressure and high temperature, surface atoms tend to evaporate due to high vapor pressure of silicon.…”

Nanoscale transport properties at silicon carbide interfaces

“…Hence, a large variety of defects are formed both at the interface and in the films, as misfit dislocations, stacking faults, twinning rotations, voids, anti-phase domains, etc. [139], making this material unsuitable for devices fabrication. Due to these limitations, for a while 3C-SiC has been defined as the "forgotten polytype" [136].…”