Vth shift in single-layer graphene field-effect transistors and its correlation with Raman inspection

• Main Authors: Wei, J., Liu, W. J., Fang, Z., Wang, Z. R., Wang, F., Wu, L., Zhang, J. F., Zhu, H. L., Sun, Xiaowei, Tran, Xuan Anh, Yu, Hongyu
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/102793; http://hdl.handle.net/10220/16505
• Institution: Nanyang Technological University

Raman measurement is carried out to understand Vth shift in single-layer graphene field-effect transistors (GFETs). The G (2D) peak shift in Raman spectra is correlated to the corresponding ΔVth during stress and recovery phases. A blue (red) shift of G and 2D peaks is seen during stress (recovery) phase, indicating the corresponding trapping (detrapping) effects in the graphene device. It is interesting to note that, after forming gas annealing (H2/Ar), the defects can be generated in graphene (evidenced by D peak of Raman spectra), leading to the increased ΔVth for both negative bias temperature instability and positive bias temperature instability in single-layer GFETs.