Ultimately Low Schottky Barrier Height at NiSi/Si Junction by Sulfur Implantation after Silicidation for Aggressive Scaling of MOSFETs


We have obtained the Schottky barrier height (SBH) of 3.4meV for an electron at the interface of nickel-silicide (NiSi) and silicon (Si) interface using sulfur (S) implantation after silicidation (S-IAS) process followed by drive-in annealing process. This value of SBH is much smaller than those previously reported. The NiSi/Si interface morphology observed by TEM indicating well interfacial flatness and no degradation occurs by sulfur implantation. The secondary-ion-mass-spectroscopy (SIMS) analysis result showed that S diffusion was suppressed by S-IAS process, leading to such a small value of SBH. In addition, S-IAS process was applied to 50nm MOSFET and the parasitic resistance was effectively lowered.

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Correspondence to Yen-Chu Yang.

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Yang, YC., Nishi, Y. & Kinoshita, A. Ultimately Low Schottky Barrier Height at NiSi/Si Junction by Sulfur Implantation after Silicidation for Aggressive Scaling of MOSFETs. MRS Online Proceedings Library 1155, 503 (2008). https://doi.org/10.1557/PROC-1155-C05-03

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