Improvements in structural and optical properties of wafer-scale hexagonal boron nitride film by post-growth annealing

• Published in: Scientific reports Vol. 9; no. 1; pp. 10590 - 8
• Main Authors: Lee, Seung Hee, Jeong, Hokyeong, Okello, Odongo Francis Ngome, Xiao, Shiyu, Moon, Seokho, Kim, Dong Yeong, Kim, Gi-Yeop, Lo, Jen-Iu, Peng, Yu-Chain, Cheng, Bing-Ming, Miyake, Hideto, Choi, Si-Young, Kim, Jong Kyu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 22.07.2019; Nature Publishing Group
• Subjects: 140/133; 140/146; 639/301/357/1018; 639/301/357/537; Annealing; Boron; Crystallinity; Humanities and Social Sciences; multidisciplinary; Optical properties; Organic chemicals; Photons; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-47093-9

Remarkable improvements in both structural and optical properties of wafer-scale hexagonal boron nitride (h-BN) films grown by metal-organic chemical vapor deposition (MOCVD) enabled by high-temperature post-growth annealing is presented. The enhanced crystallinity and homogeneity of the MOCVD-grown h-BN films grown at 1050 °C is attributed to the solid-state atomic rearrangement during the thermal annealing at 1600 °C. In addition, the appearance of the photoluminescence by excitonic transitions as well as enlarged optical band gap were observed for the post-annealed h-BN films as direct consequences of the microstructural improvement. The post-growth annealing is a very promising strategy to overcome limited crystallinity of h-BN films grown by typical MOCVD systems while maintaining their advantage of multiple wafer scalability for practical applications towards two-dimensional electronics and optoelectronics.