(Invited) In-Situ Observation of Silicon Solution Growth: Observation Principle and Effect of Al Addition to Si-Cr Solvent

The in-situ interface observation of silicon carbide (SiC) solution growth effectively elucidates various phenomena occurring at the growth front. To investigate this observation technique from the perspective of the optical transmission properties of SiC, the optical absorption properties of 3C-, 4H-, and 6H-SiC were measured over a wide range of temperatures. The obtained absorption properties indicate the optical conditions necessary for in-situ observation and the possibility of identifying different polytype inclusions. Furthermore, the effect of Al addition to the Si-Cr solvent on the SiC growth interface, where Al addition is known to be effective for growing high-quality SiC, was investigated by in situ observations. It was clarified that the presence of Al suppressed the formation of step pinning, resulting in preventing the formation of bunching steps and subsequent roughening of the growth interface.