Conference Paper

Fluorinated HfO2 gate dielectrics engineering for CMOS by pre- and post-CF4 plasma passivation

Dept. of Electron. Eng., Chang Gung Univ., Taoyuan
DOI: 10.1109/IEDM.2008.4796706 Conference: Electron Devices Meeting, 2008. IEDM 2008. IEEE International
Source: IEEE Xplore

ABSTRACT In this paper, we demonstrate TaN/fluorinated HfO2 CMOS devices, focusing on symmetry and asymmetry fluorine incorporation at top or bottom HfO2 interfaces. 16% permittivity enhancement, 65% and 91% mobility increases for electron and hole, respectively, under high electric field was achieved. Reliability of n- and p-MOSFET was improved 3 orders and 8% for GIDL and hot carrier immunity, respectively. A physical model of shallow and deep trapping level affected by fluorine was proposed to explain the NBTI and PBTI improvements.

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