Abstract
Pt or Arsenic (As)-doped polycrystalline-silicon (poly-Si) gate/HfO2 or HfO2-Al2O3/p-type Si metal oxide semiconductor (MOS) capacitors were fabricated using an atomic-layer-deposition technique, and their compatibility with poly-Si gate was investigated using a comparison with the Pt gate. The HfO2-Al2O3 stack film was found to have better As diffusion-blocking properties as a result of the rather thick amorphous interface layer including Al2O3 than that of the HfO2 film. N+ doped poly-Si gate/HfO2-Al2O3 MOS capacitors had a lower current density of −1.1× 10−9 A/cm2 at −1 V resulting in a small hysteresis voltage due to the lower As penetration and thick amorphous interface layer. These results suggest that N+ doped poly-Si gate/HfO2-Al2O3 MOS capacitors are compatible with the poly-Si gate, which is also comparable to the Pt gate.
ACKNOWLEDGEMENTS
This work was supported by the Korea Research Foundation (Grant No. KRF-2002-042-D00348), and Korean Ministry of Science and Technology through National Research Laboratories program and National R&D Project for Nano Science and Technology (M10214000097-02B1500-01500).