A novel approach for bulk micromachining of 4H-SiC by tool-based electrolytic plasma etching in HF-free aqueous solution. Issue 10 (August 2021)

• Record Type: Journal Article
• Authors: Zhan, Shunda; Dong, Bangyan; Wang, Hongqiang; Zhao, Yonghua
• Is Part Of: Journal of the European Ceramic Society. Volume 41:Issue 10(2021)
• Page Start: 5075
• Page End: 5087
• Publication Date: 2021-08
• Subjects: Electrolytic plasma etching -- Single-crystal SiC -- HF-free aqueous solution -- Material removal mechanism -- Bulk micromachining; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2021.04.012
• Languages: English
• ISSNs: 0955-2219

Abstract

Highlights: Combined process of electrolytic plasma etching with anodic oxidation. Novel bulk micromachining of SiC by tool-based electrolytic plasma etching. Both modeling and experimental investigations of EPE are presented. Experimental design and realization of microstructuring of SiC. Elucidation of process mechanism of material removal under plasma atmosphere. Abstract: Bulk micromachining of single-crystal SiC has been challenging due to its extreme stability both mechanically and chemically. To address this issue, a novel tool-based electrolytic plasma etching method is proposed, with which micropatterns and micro-holes are fabricated in SiC in a hydrofluoric acid-free aqueous solution with no need for masks. The material removal is the result of the combined effects of electrolytic plasma chemistry and physics. The chemistry refers to the reaction of Si with hydroxyl radical to form various SiOx and with H to form silanes, and the reactions of C to form volatile carbon oxides or hydrocarbons, all of which are accomplished and enhanced under the electrolytic plasma atmosphere. Besides, the local high temperature of plasma thermally promotes the evaporation or dissolution of SiO2 in NaOH solution. The tool-based electrolytic plasma etching method provides alternative approaches for the fabrication of SiC-based MEMS and devices.