Solid State Phenomena Vol. 393

Abstract: Seed crystal stabilization during the initial stage of 200-mm 4H-SiC crystal growth is critical for achieving high-quality wafers with large diameters. This study investigated the effects of heating ramp rates (0 - 6 °C/min) and SiC source powder porosity through both simulation and experimental approaches. Low ramp rates resulted in surface degradation of the seed crystal, whereas high ramp rates induced significant thermal stress, leading to cracking. Optimal ramp rates of 3 - 5 °C/min significantly minimized damage caused by seed crystal loss. Furthermore, high-porosity source powder facilitated adequate gas transport channels, thereby enhancing seed crystal stability. Crystals grown under these optimized conditions demonstrated improved edge morphology, absence of polycrystalline inclusions, and low dislocation densities, with threading screw dislocations (TSD) below 500 cm^-2 and basal plane dislocations (BPD) below 1,000 cm^-2. These results demonstrate that precise control of thermal parameters and source powder porosity offers an effective strategy for stable seed attachment and reproducible growth of high-quality, large-diameter SiC single crystals.

Abstract: This paper compares ethene and methane precursors for homoepitaxial 4H-SiC growth in planetary reactors with regards to their impact on growth rate and defectivity of the epilayers. Therefore, a comprehensive experimental study has been performed in AIXTRON G10-SiC and G5WW C planetary reactors using a standard process based on ethene and trichlorosilane precursors with conventional 150 mm n-type 4H-SiC substrates from 3 different international suppliers. Methane substituted ethene as precursor in many experiments. It was found that methane precursor can compete with ethene in terms of growth rate, epilayer thickness, and defectivity of the epilayers. By using isotopically enriched methane, Si¹²C epilayers with a ¹²C concentration of 99.96 % have been grown which can be used for SiC-based quantum technology.

Abstract: Silicon carbide (SiC) is a promising wide-bandgap semiconductor for advanced quantum technologies. Yet, despite progress in bulk and epitaxial growth, a reliable SiC-on-insulator platform remains lacking. Remote epitaxy, mediated by a 2D interlayer, offers a potential pathway to transferable SiC thin films and substrate reuse. In this work, we examine remote epitaxial growth of SiC on epitaxial graphene. We first evaluate the stability of graphene under SiC growth conditions and find that it degrades significantly at the required high temperatures, primarily due to hydrogen and silane etching. With the conditions yielding the highest-quality SiC epitaxial layer; graphene migrates above the SiC rather than remaining at the interface, demonstrating that true remote epitaxy is not achieved. These results highlight the fundamental challenges of SiC remote epitaxy on graphene and point toward critical directions for future exploration.

Abstract: In bulk SiC crystal growth using the PVT method, recrystallization within the source material leads to a decrease in growth rate and source utilization. In this study, numerical simulations were used to investigate the source temperature distribution and its effect on the growth rate and source utilization. Recrystallization in the upper and lower regions was considered separately. The results showed that reducing the source temperature gradient prevents recrystallization in the upper region, and a unidirectional gradient prevents recrystallization in the lower region, leading to higher growth rates and source utilization.