Bulk and epitaxial growth of silicon carbide

Provided is a method for producing an SiC single crystal, which is capable of greatly increasing the growth rate in a solution technique in comparison to conventional methods. A method for producing an SiC single crystal, wherein an SiC single crystal is grown by bringing a seed crystal substrate into contact with an Si-C solution that is put in a crucible and has a temperature gradient decreasing from the inside to the liquid level, and wherein the value of depth/inner diameter of the crucible is less than 1.71 and the temperature gradient of the Si-C solution from the liquid level to 10 mm below the liquid level is larger than 42°C/cm.

Method for producing sic single crystal

https://iopscience.iop.org/article/10.1088/1361-6641/aad831/pdf

Review of SiC crystal growth technology

Power electronics belongs to the future key technologies in order to increase system efficiency as well as performance in automotive and energy saving applications. Silicon is the major material for electronic switches since decades. Advanced fabrication processes and sophisticated electronic device designs have optimized the silicon electronic device performance almost to their theoretical limit. Therefore, to increase the system performance, new materials that exhibit physical and chemical properties beyond silicon need to be explored. A number of wide bandgap semiconductors like silicon carbide, gallium nitride, gallium oxide, and diamond exhibit outstanding characteristics that may pave the way to new performance levels. The review will introduce these materials by (i) highlighting their properties, (ii) introducing the challenges in materials growth, and (iii) outlining limits that need innovation steps in materials processing to outperform current technologies.

Power Electronic Semiconductor Materials for Automotive and Energy Saving Applications - SiC, GaN, Ga2O3, and Diamond.

Top-seeded solution growth of three-inch-diameter 4H-SiC using convection control technique

A long-term growth of high-quality 4H-SiC single crystals by a top-seeded solution growth method using a Si–Cr-based melt was investigated. A new growth technique called “solution growth on concave surface” (SGCS) was developed to help prevent solvent inclusions. The concave shape of the growth surface was achieved by controlling the meniscus height, which enhances the step provision from the periphery to the center. In contrast, under the growth surface, the solution flows from the center to the periphery through convection by inductive heating. The opposite directions of the step flow and solution flow during solution growth create a smooth surface without solvent inclusions. SGCS was used to successfully grow a 1-in. diameter 4H-SiC crystal with a thickness of 30 mm, which is the thickest reported for a solution growth technique, and 1.7-in. diameter high-quality wafers without solvent inclusions were obtained. Schottky barrier diodes were fabricated on 4H-SiC substrates grown by SGCS, which demonstrat...

Solution Growth on Concave Surface of 4H-SiC Crystal

High-speed solution growth using Si-Cr based melt has been performed on on-axis 4H-SiC(0001) at a high temperature of about 2000°C. The maximum growth rate for one-hour growth reaches to 1120 m/h, while the typical growth rate of growth for 2h is about 500 m/h. A large crystal that is about 25 mm in diameter and 1650 m in thickness can be obtained by growth for 5h. The crystal quality is confirmed to be homogeneous by X-ray diffraction and X-ray topography, because FWHM is less than 30 arcsec. Etch pit density of the threading dislocations in the grown crystal is 103-104 cm-2, and that of basal plane dislocation is 2×102-3×103 cm-2. Resistivity of the crystals grown by the solution growth is comparable to those of crystals grown by physical vapor transport technique.

High-Speed Growth of High-Quality 4H-SiC Bulk by Solution Growth Using Si-Cr Based Melt

In this study, we have investigated the rate-limiting process of 4H-SiC solution growth using Si-Cr based melt, and have tried high-speed growth. It is revealed that the rate-limiting process of SiC growth under our experimental condition is interface kinetics, which can be controlled by such factors as temperature and supersaturation of carbon. By enhancing the interface kinetics, SiC crystal has been grown at a high rate of 2 mm/h. The FWHM values of X-ray rocking curves and threading dislocation density of the grown crystals are almost the same as those of seed crystal. Possibility of high-speed and high-quality growth of 4H-SiC has been indicated.

High-Speed Growth of 4H-SiC Single Crystal Using Si-Cr Based Melt

We have grown high-quality long cylindrical (12 mm thick) 4H-SiC bulk crystals by the meniscus formation technique, which was first applied for the solution growth of bulk SiC. It enabled long-term growth by suppressing parasitic reactions such as polycrystal precipitation around the seed crystal. In addition, we could control the growth angle from −22° to 61° by adjusting the meniscus height. The thickness of the grown cylindrical crystals was 12 mm, which is the largest reported until now, and corresponded to a growth rate of 0.6 mm/h. Smooth morphology growth was maintained on the (000-1) C-face. In cross-sectional transmission optical microscopy images, few solvent inclusions and voids were observed. XRD measurements revealed that the FWHM values of the grown crystals were almost the same as those of the seed crystal.

Hironori Daikoku

Papers

Top-seeded solution growth of three-inch-diameter 4H-SiC using convection control technique

Solution Growth on Concave Surface of 4H-SiC Crystal

High-Speed Growth of High-Quality 4H-SiC Bulk by Solution Growth Using Si-Cr Based Melt

High-Speed Growth of 4H-SiC Single Crystal Using Si-Cr Based Melt

Top-Seeded Solution Growth of 4H-SiC Bulk Crystal Using Si-Cr Based Melt