Large-Scale CMOS-Compatible Process for growing Si-BC8 Nanowires

• Published in: 2020 Joint International EUROSOI Workshop and International Conference on Ultimate Integration on Silicon (EUROSOI-ULIS) pp. 1 - 4
• Main Authors: Mazzotta, I., Rigoni, F., Irrera, F., Riello, P., Quaranta, S., Latini, A., Palma, F.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-09-2020
• Subjects: Catalysis; CMOS compatible process; Electromagnetic heating; microwave CVD; Nanowires; Si-BC8 crystallographic phase; Silicon; Silicon nanowires; Substrates; Systematics; Temperature
• ISSN: 2472-9132
• DOI: 10.1109/EUROSOI-ULIS49407.2020.9365521

A novel, low temperature process for the growth of silicon nanowires containing a monocrystalline Si-BC8 phase is presented. Silicon atoms in Si-BC8 phase are arranged in body-centered-cubic unit cells resulting into a different energy-wavefactor diagram compared to the silicon diamond cubic phase. Indeed, Si-BC8 possesses a direct band gap as low as 30 meV at room temperature. These characteristics are highly desirable for a large variety of applications, requiring CMOS-compatible manufacturing. The growth was performed in a CVD reactor under exposure to microwaves, and employing Sn nanospheres and SiH 4 as catalyst and precursor gas, respectively. Microwaves allowed for selective heating of the metal catalyst while keeping the substrate at low temperature. Systematic structural analysis and a phenomenological model for Si-BC8 phase formation are discussed.