IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Tuesday Sessions
       Session DI-TuM

Paper DI-TuM3
Electrical and Physical Characteristics of Sputtered HfO@sub 2@ Films for Alternative Gate Dielectrics

Tuesday, October 30, 2001, 9:00 am, Room 130

Session: High K Dielectrics II
Presenter: S.-W. Nam, Yonsei University, Korea
Authors: S.-W. Nam, Yonsei University, Korea
J.-H. Yoo, Yonsei University, Korea
H.-J. Choi, Yonsei University, Korea
S. Nam, Yonsei University, Korea
D.-H. Ko, Yonsei University, Korea
J.-H. Ku, R&D Center Semiconductor Samsung Electronics Co., Korea
M.-H. Cho, Yonsei University, Korea
S. Choi, R&D Center Semiconductor Samsung Electronics Co., Korea
C.-W. Yang, Sungkyunkwan University, Korea
Correspondent: Click to Email
SiO@sub 2@ has been used as the primary gate dielectric material in MOSFET devices for over 40 years. As the thickness of SiO@sub 2@ decreases, a direct tunneling of carriers through the potential barrier occurs, which results in the significant leakage current through the SiO@sub 2@ layer. Because of this issue, a conventional SiO@sub 2@ process shows limitation in the fabrication of CMOS devices in sub-2.0nm thickness regime. Therefore, the development of alternative dielectric materials is required for the fabrication of sub-0.1µm MOSFET devices. Dielectric materials with a high dielectric constant, large band-gap, low interface state density, and good thermal stability have drawn a lot of attention as alternative gate dielectric materials. Recently, HfO@sub 2@ has been considered as promising alternative materials due to high dielectric constant and good thermal stability with Si substrates. We have studied the microstructures and electrical properties of HfO@sub 2@ films. The HfO@sub 2@ thin films on (100) silicon substrate treated by a HF solution, chemical oxide, and NH@sub 3@ nitridation were deposited by reactive dc magnetron sputtering for gate dielectrics applications, followed by Pt sputtering for gate electrode. The resulting films were analyzed by ellipsometry, XRD, HRTEM, RBS, and XPS/AES. The crystalline peaks with orthorhombic phase of HfO@sub 2@ were observed in the films annealed at elevated temperatures (>650°C). By HRTEM and XPS/AES analyses, we observed the properties of HfO@sub 2@ films and the interfacial layers between the HfO@sub 2@ films and the Si substrate upon annealing. The electrical properties were assessed by C-V and I-V measurements for MOS structures.