Low-Temperature Direct Growth of Amorphous Boron Nitride Films for High-Performance Nanoelectronic Device Applications
Seyed Mehdi Sattari‐Esfahlan, Hyoung Gyun Kim, Sang Hwa Hyun, Jun‐Hui Choi, Hyun Sik Hwang, Eui‐Tae Kim, Hyeongsik Park, Jae‐Hyun Lee
Abstract
High Resolution Image Download MS PowerPoint Slide We successfully demonstrated the improvement and stabilization of the electrical properties of a graphene field effect transistor by fabricating a sandwiched amorphous boron nitride (a-BN)/graphene (Gr)/a-BN using a directly grown a-BN film. The a-BN film was grown via low-pressure chemical vapor deposition (LPCVD) at a low growth temperature of 250 °C and applied as a protection layer in the sandwiched structure. Both structural and chemical states of the as-grown a-BN were verified by various spectroscopic and microscopic analyses. We analyzed the Raman spectra of Gr/SiO 2 and a-BN/Gr/a-BN structures to determine the stability of the device under exposure to ambient air. Following exposure, the intensity of the 2D/G-peak ratio of Gr/SiO 2 decreased and the position of the G and 2D peaks red-shifted due to the degradation of graphene. In contrast, the peak position of encapsulated graphene is almost unchanged. We also confirmed that the mobility of a-BN/Gr/a-BN structure is 17,941 cm 2 /Vs. This synthetic strategy could provide a facile way to synthesize uniform a-BN film for encapsulating various van der Waals materials, which is beneficial for future applications in nanoelectronics.