Mobility enhancement in TaN metal-gate MOSFETs using tantalum incorporated HfO2 gate dielectric

Xiòngfei Yu*, Chunxiang Zhu, M. F. Li, Albert Chin, M. B. Yu, A. Y. Du, Dim Lee Kwong

*Corresponding author for this work

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

TaN metal-gate nMOSFETs using HfTaO gate dielectrics have been investigated for the first time. Compared to pure HfO2, a reduction of one order of magnitude in interface state density (Dit) was observed in HfTaO film. This may be attributed to a high atomic percentage of Si-O bonds in the interfacial layer between HfTaO and Si. It also suggests a chemical similarity of the HfTaO-Si interface to the high-quality SiO2-Si interface. In addition, a charge trapping-induced threshold voltage (Vth) shift in HfTaO film with constant voltage stress was 20 times lower than that of HfO2. This indicates that the HfTaO film has fewer charged traps compared to HfO2 film. The electron mobility in nMOSFETs with HfO2 gate dielectric was significantly enhanced by incorporating Ta.

Original languageEnglish
Pages (from-to)501-503
Number of pages3
JournalIEEE Electron Device Letters
Volume25
Issue number7
DOIs
StatePublished - 1 Jul 2004

Fingerprint Dive into the research topics of 'Mobility enhancement in TaN metal-gate MOSFETs using tantalum incorporated HfO<sub>2</sub> gate dielectric'. Together they form a unique fingerprint.

Cite this