Lateral Enlargement Growth Mechanism of 3C-SiC on Off-Oriented 4H-SiC Substrates

Abstract

We introduce a 3C-SiC growth concept on off-oriented 4H-SiC substrates using a sublimation epitaxial method. A growth model of 3C-SiC layer development via a controlled cubic polytype nucleation on in situ formed on-axis area followed by a lateral enlargement of 3C-SiC domains along the step-flow direction is outlined. Growth process stability and reproducibility of high crystalline quality material are demonstrated in a series of 3C-SiC samples with a thickness of about 1 mm. The average values of full width at half-maximum of ω rocking curves on these samples vary from 34 to 48 arcsec indicating high crystalline quality compared to values found in the literature. The low temperature photoluminescence measurements also confirm a high crystalline quality of 3C-SiC and indicate that the residual nitrogen concentration is about 1-2×10 16 cm -3 . Such 3C-SiC growth concept may be applied to produce substrates for homoepitaxial 3C-SiC growth or seeds which could be explored in bulk growth of 3C-SiC.

Cubic silicon carbide as a potential photovoltaic material

“…Such growth rates are attractive for a production of 3C-SiC material for photovoltaics. In our case, we have used a moderate the growth rate but high enough to prepare a free standing nominally undoped 3C-SiC substrate [6] for ion implantation or subsequent homoepitaxial growth using a boron doped source. In the latter case the boron doped polycrystalline source materials were fabricated using a PVT bulk method with a mixture of boron carbide powder and SiC carbide powder.…”

“…The growth is carried out in vacuum and ensures an efficient transfer of vapor and dopant species from the source to the substrate. Our 3C-SiC growth approach allows us to control initial nucleation of 3C-SiC domains which laterally enlarge and completely cover the substrate surface [6]. Thereby a 3C-SiC material with very few domains is formed and a high crystalline quality is achieved.…”

“…However, it is a pronounced challenge to obtain large domains, and domain sizes were less than a millimeter even though some growth parameters could influence the lateral domain expansion [8]. A new 3C-SiC growth approach on off-oriented 4H-SiC allows controlling initial nucleation of 3C-SiC and significantly reduce the density of structural defects [6]. Moreover, it has been demonstrated that this approach allows very high polytype stability and excellent reproducibility.…”

Single Domain 3C-SiC Growth on Off-Oriented 4H-SiC Substrates

“…10 The schematic illustration of the growth setup is shown in Figure 1.The materials are placed inside an inductively heated graphite crucible on top of each other in a sandwich-like arrangement with a tantalum foil at the bottom, followed by a polycrystalline SiC plate (source material), a graphite spacer with an opening for vapor species transport, a substrate and a graphite plate to prevent backside sublimation of the substrate. The tantalum foil acts as a carbon getter at elevated temperatures and leads to an increased concentration of silicon in the vapor phase inside the crucible.…”

“…10 The LE mechanism allows to localize the initial nucleation of 3C-SiC domains on an in situ formed large terrace with an on-axis area at the edge of hexagonal substrate. These domains enlarges along the step-flow [11][12][13][14][15][16][17][18][19][20] direction and completely cover the surface.…”