Gradient area-selective deposition for seamless gap-filling in 3D nanostructures through surface chemical reactivity control

• Published in: Nature communications Vol. 13; no. 1; pp. 7597 - 10
• Main Authors: Nguyen, Chi Thang, Cho, Eun-Hyoung, Gu, Bonwook, Lee, Sunghee, Kim, Hae-Sung, Park, Jeongwoo, Yu, Neung-Kyung, Shin, Sangwoo, Shong, Bonggeun, Lee, Jeong Yub, Lee, Han-Bo-Ram
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 09.12.2022; Nature Publishing Group UK; Nature Portfolio
• Subjects: Atomic layer epitaxy; Chemical reactions; Density functional theory; Fabrication; High aspect ratio; Inhibitors; Monte Carlo simulation; Nanofabrication; Titanium dioxide
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-35428-6

The integration of bottom-up fabrication techniques and top-down methods can overcome current limits in nanofabrication. For such integration, we propose a gradient area-selective deposition using atomic layer deposition to overcome the inherent limitation of 3D nanofabrication and demonstrate the applicability of the proposed method toward large-scale production of materials. Cp(CH ) Ti(OMe) is used as a molecular surface inhibitor to prevent the growth of TiO film in the next atomic layer deposition process. Cp(CH ) Ti(OMe) adsorption was controlled gradually in a 3D nanoscale hole to achieve gradient TiO growth. This resulted in the formation of perfectly seamless TiO films with a high-aspect-ratio hole structure. The experimental results were consistent with theoretical calculations based on density functional theory, Monte Carlo simulation, and the Johnson-Mehl-Avrami-Kolmogorov model. Since the gradient area-selective deposition TiO film formation is based on the fundamentals of molecular chemical and physical behaviours, this approach can be applied to other material systems in atomic layer deposition.