Scaling effects on gate leakage current

Adv. LSI Technol. Lab., Toshiba Corp., Yokohama, Japan
IEEE Transactions on Electron Devices (Impact Factor: 2.47). 09/2003; 50(8):1779 - 1784. DOI: 10.1109/TED.2003.815140
Source: IEEE Xplore


Scaling effects on direct tunneling gate leakage current are analyzed by utilizing new models implemented to perform self-consistent calculation between the direct tunneling, the band-gap narrowing (BGN) and the incomplete impurity ionization. This calculation is indispensable for reproducing the measured gate current-gate voltage characteristics in the device simulation. As a result, it is concluded that the scaling of the gate width cannot suppress the gate leak, even if the specification of the threshold voltage is relaxed in order to shrink the gate width. It is also found that the scaling of the gate length cannot suppress the gate leak unless the vertical field is strong.

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Available from: Hiroshi Watanabe, Sep 17, 2013
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    • "The positive charge stored by DBs is, in this way, dependent on the electric field that determines E T − E F inside the SiON film, which has a notable influence on the gate current through the SiON film, as discussed in Section IV. It is noteworthy that the precise calculation of E F is indispensable for estimating the amount of the positive charge, which is described in detail in [50] and [51]. In addition, E F has a significant influence on the estimation of the incomplete depletion layer [52] and the weak accumulation layer [53] at the interface with the gate polysilicon. "
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