Department of Material Science and Engineering, Ajou University, Suwon16499, Korea.
Department of Materials Science and Engineering, Seoul National University, Seoul08826, Korea.
ACS Appl Mater Interfaces. 2023 Feb 8;15(5):7274-7281. doi: 10.1021/acsami.2c18706. Epub 2023 Jan 31.
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 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 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 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/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.
我们成功地通过使用直接生长的非晶态氮化硼(a-BN)膜制造夹心结构的非晶态氮化硼(a-BN)/石墨烯(Gr)/非晶态氮化硼(a-BN)，改善和稳定了石墨烯场效应晶体管的电学性能。该 a-BN 薄膜采用低压化学气相沉积(LPCVD)在 250°C 的低温下生长，并用作夹心结构中的保护层。通过各种光谱和显微镜分析验证了所生长的 a-BN 的结构和化学状态。我们分析了 Gr/SiO 和 a-BN/Gr/a-BN 结构的拉曼光谱，以确定器件在暴露于环境空气中的稳定性。暴露后，由于石墨烯的降解，Gr/SiO 中 2D/G-峰强度比降低，G 和 2D 峰的位置红移。相比之下，封装石墨烯的峰位置几乎不变。我们还证实，a-BN/Gr/a-BN 结构的迁移率为 17941cm/Vs。这种合成策略可以为封装各种范德华材料提供一种简便的方法来合成均匀的 a-BN 薄膜，这有利于未来在纳米电子学中的应用。
