Single-crystalline SiC integrated onto Si-based substrates via plasma-activated direct bonding. Issue 14 (1st October 2020)

• Record Type: Journal Article
• Authors: Kang, Qiushi; Wang, Chenxi; Niu, Fanfan; Zhou, Shicheng; Xu, Jikai; Tian, Yanhong
• Is Part Of: Ceramics international. Volume 46:Issue 14(2020)
• Page Start: 22718
• Page End: 22726
• Publication Date: 2020-10-01
• Subjects: Direct bonding -- Plasma activation -- Silicon carbide -- Bonding interface; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.06.036
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: We propose a plasma-activated direct bonding process at low temperatures (≤200 °C) to form heterostructures between single-crystalline SiC and conventional Si-based substrates (SiO2, Si, and glass) without any interlayers. Surface activation was performed via an inductively coupled O2 plasma for 60 s with a lower bombardment damage position. The SiC surfaces were much more hydrophilic after activation, and the generation of defect states was suppressed. Consequently, void-free and robust bonding interfaces of SiC/SiO2, SiC/Si and SiC/glass were successfully achieved. There were no carbon-enriched layers across the bonding interfaces, which could improve the electrical properties of SiC-based devices. Additionally, the bonding interface of SiC/glass exhibited excellent optical transparency, and interfacial corrosion resistance was confirmed via immersion tests in biological solutions. This bonding method provides a feasible route towards industry-compatible heterogeneous integration of single-crystalline bulk SiC onto Si-based platforms for electronic, optical, mechanical, and biomedical applications.