| Autor: |
Sugimoto, Youhei, Kajiwara, Masanari, Yamamoto, Keisuke, Suehiro, Yuusaku, Wang, Dong, Nakashima, Hiroshi |
| Předmět: |
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| Zdroj: |
Applied Physics Letters; 9/10/2007, Vol. 91 Issue 11, p112105, 3p, 1 Diagram, 1 Chart, 3 Graphs |
| Abstrakt: |
The effective work function ([uppercase_phi_synonym]m,eff) of TaN on HfO2 after postmetallization annealing (PMA) was investigated using TaN/HfO2/SiO2/Si as a sample structure. We found that [uppercase_phi_synonym]m,eff on HfO2 is stable at PMA temperatures of less than 600 °C and is 4.6 eV, which is approximately 0.2 eV higher than that on SiO2. In contrast, [uppercase_phi_synonym]m,eff is modulated by PMA at temperatures greater than 750 °C. An analysis by x-ray photoelectron spectroscopy suggests that the increased [uppercase_phi_synonym]m,eff is strongly related to Ta oxide formation near the TaN/HfO2 interface. The modulation of [uppercase_phi_synonym]m,eff on HfO2 is discussed on the basis of intrinsic and extrinsic Fermi level pinning due to Ta–O bond formation at the TaN/HfO2 interface. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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