Work Function Tuning and Doping Optimization of 22-nm HKMG Raised SiGe/SiC Source–Drain FinFETs

详细信息    查看全文

• 作者：F. A. Md Rezali ; M. A. S. Abd Rasid ; N. A. F. Othman…
• 关键词：Halo doping ; source/drain doping ; substrate doping ; work function ; Taguchi method ; Pareto ANOVA
• 刊名：Journal of Electronic Materials
• 出版年：2017
• 出版时间：March 2017
• 年：2017
• 卷：46
• 期：3
• 页码：1567-1575
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Optical and Electronic Materials; Characterization and Evaluation of Materials; Electronics and Microelectronics, Instrumentation; Solid State Physics;
• 出版者：Springer US
• ISSN：1543-186X
• 卷排序：46

文摘

The basic requirements on process design of extremely scaled devices involve appropriate work function and tight doping control due to their significant effect on the threshold voltage as well as other critical electrical parameters such as drive current and leakage. This paper presents a simulation study of 22-nm fin field-effect transistor (FinFET) performance based on various process design considerations including metal gate work function (WF), halo doping (N_halo), source/drain doping (N_sd), and substrate doping (N_sub). The simulations suggest that the n-type FinFET (nFinFET) operates effectively with lower metal gate WF while the p-type FinFET (pFinFET) operates effectively with high metal gate WF in 22-nm strained technology. Further investigation shows that the leakage reduces with increasing N_halo, decreasing N_sd, and increasing N_sub. Taguchi and Pareto analysis-of-variance approaches are applied using an L₂₇ orthogonal array combined with signal-to-noise ratio analysis to determine the best doping concentration combination for 22-nm FinFETs in terms of threshold voltage (V_t), saturation current (I_on), and off-state current (I_off). Since there is a tradeoff between I_on and I_off, the design with the nominal-is-best V_t characteristic is proposed, achieving nominal V_t of 0.259 V for the nFinFET and −0.528 V for the pFinFET. Pareto analysis revealed N_halo and N_sub to be the dominant factor for nFinFET and pFinFET performance, respectively.