A systematic approach of understanding and retaining pmos compatible work function of metal electrodes on HfO2 gate dielectrics

Rashmi Jha, Jiyoung Chung, Bei Chen, Robert Nemanich, Veena Misra

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations

Abstract

In this work we have performed Ultraviolet Photoelectron Spectroscopy (UPS) and X-Ray Photoelectron Spectroscopy (XPS) on: (i) 40Å of Ru deposited on 20Å of ALD-HfO2 (Ru-HfO2), (ii) 40Å of Re deposited on 20Å of ALD-HfO2 (Re-HfO2), and (iii) 40Å of W deposited on 20Å of ALD-HfO2 (W-HfO2) in as deposited as well as after 600°C in-situ anneal exposure. The samples with Ru and Re indicated significant reduction in the oxygen content and shift in the Hf peaks towards higher binding energy after anneal as compared to the as deposited state. The loss of oxygen after anneal was associated with the reduction in the surface work function of Ru and Re measured by UPS. However, the sample with W showed a redistribution of oxygen after anneal leading to the formation of multiple oxides of W having a net higher surface work function. The spectroscopic measurements were correlated with the electrical measurements made on MOS capacitors with Ru metal gates on HfO2 gate dielectric. The results indicated that the oxygen content at metal/high-k interface plays an important role in governing the effective work function of Ru on HfO 2 gate dielectric.

Original languageEnglish (US)
Title of host publicationMaterials Research Society Symposium Proceedings
Pages37-42
Number of pages6
Volume917
Publication statusPublished - 2006
Externally publishedYes
Event2006 MRS Spring Meeting - San Francisco, CA, United States
Duration: Apr 17 2006Apr 21 2006

Other

Other2006 MRS Spring Meeting
CountryUnited States
CitySan Francisco, CA
Period4/17/064/21/06

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ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials

Cite this

Jha, R., Chung, J., Chen, B., Nemanich, R., & Misra, V. (2006). A systematic approach of understanding and retaining pmos compatible work function of metal electrodes on HfO2 gate dielectrics. In Materials Research Society Symposium Proceedings (Vol. 917, pp. 37-42)