,Improved performance of back-gate MoS2 transistors by NH3-plasma treating high-k gate dielectrics

• 作 者: Jian-Ying Chen Xin-Yuan Zhao Lu Liu Jing-Ping Xu
• 机 构: Ningbo Information Technology Service Center, Ningbo 315400, China“,”School of Optical and Electroni
• 出 处: 中国物理B（英文版）
• 发表日期: 2019年12期
• 关键词: MoS2 transistor high-k dielectric NH3-plasma treatment oxygen vacancy mobility

NH3-plasma treatment is used to improve the quality of the gate dielectric and interface.Al2O3 is adopted as a buffer layer between HfO2 and MoS2 to decrease the interface-state density.Four groups of MOS capacitors and back-gate transistors with different gate dielectrics are fabricated and their C-V and I-V characteristics are compared.It is found that the Al2O3/HfO2 back-gate transistor with NH3-plasma treatment shows the best electrical performance:high on-off current ratio of 1.53 × 107,higher field-effect mobility of 26.51 cm2/V.s,and lower subthreshold swing of 145 mV/dec.These are attributed to the improvements of the gate dielectric and interface qualities by the NH3-plasma treatment and the addition of Al2O3 as a buffer layer.