Chien, Nguyen Dang, and Luu The Vinh. “Design Optimization of Extremely Short-Channel Graded Si SiGe Heterojunction Tunnel Field-Effect Transistors for Low Power Applications”. Vietnam Journal of Science and Technology, vol. 51, no. 6, Mar. 2018, pp. 757-68, doi:10.15625/2525-2518/51/6/11642.