IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Monday Sessions
       Session DI1-MoP

Paper DI1-MoP8
Interface Formation and Electrical Properties of TiN@sub x@ (Titanium Nitride)/HfO@sub 2@/Si Structure for Application in Gate Electrode

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: High K Dielectrics Poster Session
Presenter: Y.S. Ahn, Sungkyunkwan University, Korea
Authors: Y.S. Ahn, Sungkyunkwan University, Korea
K.J. Kim, Sungkyunkwan University, Korea
S.H. Ban, Sungkyunkwan University, Korea
N.-E. Lee, Sungkyunkwan University, Korea
S. Yang, Sungkyunkwan University, Korea
K. Roh, Sungkyunkwan University, Korea
Y.H. Roh, Sungkyunkwan University, Korea
Correspondent: Click to Email
Recent extensive research activities on HfO@sub2@ as a high-k gate dielectric material are focused on the layer formation and interfacial properties between HfO@sub2@ and Si substrate. For the integration of HfO@sub2@ in MOS structures, metals as gate electrode materials are expected to be required. One of candidates for metal gate electrode is CVD tungsten. For application of CVD-W as a gate electrode, a diffusion barrier such as TiN@subx@ are often necessary to avoid the chemical etching of gate dielectrics by F atoms in the CVD precursor gas, WF@sub6@, resulting in increased leakage current. In this work, interface formation and electrical properties between TiN@subx@ and HfO@sub2@ for application of gate electrode were investigated as a function of annealing temperature. Hf layers were deposited on n-type Si(001) using rf magnetron sputter deposition. HfO@sub2@ layers of 6-7 nm thickness were formed at 500 °C by a thermal oxidation of the Hf layers for 120 min in furnace with O@sub2@ ambient. Further thermal annealing at 500 °C in N@sub2@ ambient for 60 min was carried out in order to reduce the fraction of silicate glasses formed. Then, TiN@subx@ layers of 100 nm were deposited at room-temperature by reactive d.c magnetron sputtering using Ar and N@sub2@ mixed in flow ratios of 6:1 and 6:3 at the working pressure of 4x10@super-3@ Torr and at the source power of 100 W. Phase identification of TiN@subx@ layers before and after thermal annealing of TiN@subx@/HfO@sub2@/Si at 650, 750, and 850°C in furnace, respectively, was carried out by XRD. Depth profiling analysis of Ti, Si, Hf, N, and O element for TiN@subx@/HfO@sub2@/Si structure was performed by Auger electron spectroscopy (AES). Sheet resistances of TiN@subx@/HfO@sub2@/Si systems were measured by a four-point probe. The interfacial reaction of TiN@subx@/HfO@sub2@ will be discussed by measuring the chemical binding states at the interface using XPS.