Electrical Properties and Interfacial Issues of HfO2/Ge MIS Capacitors Characterized by the Thickness of La2O3 Interlayer

Lu Zhao; Hongxia Liu; Xing Wang; Yongte Wang; Shulong Wang

doi:10.3390/nano9050697

Electrical Properties and Interfacial Issues of HfO₂/Ge MIS Capacitors Characterized by the Thickness of La₂O₃ Interlayer

Nanomaterials (Basel). 2019 May 4;9(5):697. doi: 10.3390/nano9050697.

Authors

Lu Zhao¹, Hongxia Liu², Xing Wang³, Yongte Wang⁴, Shulong Wang⁵

Affiliations

¹ Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China. lzhaoxd@163.com.
² Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China. hxliu@mail.xidian.edu.cn.
³ Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China. xwangsme@xidian.edu.cn.
⁴ Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China. mikewyt@163.com.
⁵ Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China. slwang@xidian.edu.cn.

Abstract

Effects of the La₂O₃ passivation layer thickness on the interfacial properties of high-k/Ge interface are investigated systematically. In a very thin range (0~15 cycles), the increase of La₂O₃ passivation layer deposition cycles improves the surface smoothness of HfO₂/Ge structures. The capacitance-voltage (C-V) characteristics show that the thickness of La₂O₃ passivation layer can affect the shift of flat band voltage (V_FB), hysteretic behaviors, and the shapes of the dual-swept C-V curves. Moreover, significant improvements in the gate leakage current and breakdown characteristics are also achieved with the increase of La₂O₃ interlayer thickness.

Keywords: Ge surface engineering; La2O3 passivation layer; atomic layer deposition; electrical properties.

Publication types

Letter

Abstract

Publication types

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