Characteristics and Mechanism of Catalyst-Referred Etching Method: Application to 4H-SiC
Pho Van Bui, Yasuhisa Sano, Yoshitada Morikawa, and Kazuto Yamauchi†
Department of Precision Science and Technology, Graduate School of Engineering, Osaka University
2-1 Yamada-Oka, Suita, Osaka 565-00817, Japan
A novel abrasive-free planarization method named catalyst-referred etching (CARE) was developed. A polishing pad is coated with a catalytic material to promote chemical etching of the work substrate. During processing, the topmost areas of the work substrate, which are in contact with the catalyst surface, are selectively etched off. Atomically highly ordered surfaces are obtained for many types of work substrates. In this paper, the removal characteristics and mechanism of CARE for single crystalline 4H-SiC are reviewed.
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