J. G. Guan

Publications (6)7.69 Total impact

• Article: Improved electrical properties of Ge metal-oxide-semiconductor capacitor with HfTa-based gate dielectric by using TaOxNy interlayer

  X. F. Zhang, J. P. Xu, C. X. Li, P. T. Lai, C. L. Chan, J. G. Guan
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  ABSTRACT: HfTa-based oxide and oxynitride with or without Ta O _x N _y interlayer are fabricated on Ge substrate to form metal-oxide-semiconductor (MOS) capacitors. Their electrical properties and reliabilities are measured and compared. The results show that the MOS capacitor with a gate stack of HfTa-based oxynitride and thin Ta O _x N _y interlayer exhibits low interface-state/oxide-charge densities, low gate leakage, small hysteresis, small capacitance equivalent thickness (∼0.94 nm ) , and high dielectric constant (∼24) . All these should be attributed to the blocking role of the Ta O _x N _y interlayer against penetration of O into the Ge substrate and interdiffusions of Hf, Ge, and Ta, thus effectively suppressing the formation of unstable low- k Ge O _x and giving a superior Ta O _x N _y/ Ge interface. Moreover, incorporation of N into both the interlayer and high- k dielectric greatly improves device reliability through the formation of strong N-related bonds.
  Applied Physics Letters 07/2008; · 3.84 Impact Factor
• Article: Influence of sidewall spacer on threshold voltage of MOSFET with high-k gate dielectric.

  J. P. Xu, F. Ji, P. T. Lai, J. G. Guan
  Microelectronics Reliability. 01/2008; 48:181-186.
• Article: A fringing-capacitance model for deep-submicron MOSFET with high-k gate dielectric.

  F. Ji, J. P. Xu, P. T. Lai, J. G. Guan
  Microelectronics Reliability. 01/2008; 48:693-697.
• Article: A 2D threshold-voltage model for small MOSFET with quantum-mechanical effects.

  J. P. Xu, Y. P. Li, P. T. Lai, W. B. Chen, S. G. Xu, J. G. Guan
  Microelectronics Reliability. 01/2008; 48:23-28.
• Source

  Available from: hku.hk

  Article: Improved electrical properties of metal-oxide-semiconductor capacitor with HfTiON gate dielectric by using HfSiON interlayer

  J. P. Xu, F. Ji, C. X. Li, P. T. Lai, J. G. Guan, Y. R. Liu
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  ABSTRACT: Metal-oxide-semiconductor (MOS) capacitor with Hf Ti O N / Hf Si O N stack structure as high- k gate dielectric is fabricated, and its electrical properties are compared with those of a similar device with HfTiON only as gate dielectric. Experimental results show that the device with Hf Ti O N / Hf Si O N gate dielectric exhibits better interface properties, lower gate leakage current, and enhanced high-field reliability. All these improvements should be attributed to the fact that the HfSiON buffer layer effectively blocks the diffusion of Ti atoms to the Si substrate, thus resulting in a Si O ₂/ Si -like Hf Si O N / Si interface.
  Applied Physics Letters 11/2007; · 3.84 Impact Factor
• Article: Influence of sidewall spacer on threshold voltage of MOSFET with high-k gate dielectric

  J.P. Xu, F. Ji, P.T. Lai, J.G. Guan
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  ABSTRACT: In this paper, an analytical expression of the gate-dielectric fringing-potential distribution is derived for high-k gate-dielectric MOSFET through a conformal-mapping transformation method for the first time. Based on the fringing-potential distribution, the threshold-voltage model of the MOSFET is improved, and the influence of sidewall spacer on the threshold voltage is discussed in detail. Calculated results indicate that low-k sidewall spacer can alleviate the fringing-field effect.
  Microelectronics Reliability.