Conformal Growth of Hexagonal Boron Nitride on High-Aspect-Ratio Silicon-Based Nanotrenches
Jiye Kim, Jiye Kim, Kyung‐Yeon Doh, Seokho Moon, Changwon Choi, Hokyeong Jeong, Jaewon Kim, Jaewon Kim, Wonseok Yoo, Kyungwook Park, Kyeongock Chong, Chunhyng Chung, Hanmei Choi, Si‐Young Choi, Donghwa Lee, Jong Kyu Kim, Jong Kyu Kim
Abstract
We successfully accomplished the conformal growth of sp 2 -hybridized few-layer h-BN over an array of Si-based nanotrenches with a 45 nm pitch and an aspect ratio of ∼7:1 by using the pulsed-mode metal–organic chemical vapor deposition (MOCVD) method. Surface-sensitive X-ray absorption fine structure spectroscopy and density functional theory calculations revealed that the B–O bonds formed on the noncatalytic SiO 2 surface act as nucleation sites for the subsequential formation of mixed sp 2 - and sp 3 -hybridized BON 2 and BN 3 at the very initial stage of the pulsed-mode injection of MOCVD precursors, enabling the conformal growth of few-layer sp 2 -hybridized h-BN with an excellent step coverage. We believe that these results can provide a broad avenue for the implementation of fascinating two-dimensional layered materials for current state-of-the-art three-dimensional Si-based nanoscale architectures, overcoming the downscaling limits.