Dopant segregation (DS) technique has been extensively employed to tune Schottky barrier heights (SBHs) of NiSi/Si diodes, either leading to reduced specific contact resistivity ( $\rho _{\text {c}}$ ) in source/drain (S/D) Ohmic contacts, or enhanced current drivability in Schottky barrier S/D MOSFET (SB-MOSFET) where metallic NiSi is employed as S/D. A capacitance–voltage ( ${C}$ – ${V}$ ) method is usually adopted to reliably extract the SBHs of NiSi/Si for investigating the effectiveness of such a DS technique. In order to avoid large reverse leakage current which rules out the possibility of SBHs extraction during ${C}$ – ${V}$ measurements, dopants with opposite polarity to that in epitaxial Si substrate segregate at the NiSi/Si interface, for instance, boron DS (B DS) for NiSi/n-Si and arsenic DS (As DS) for NiSi/p-Si. This, however, raises one critical question, i.e., NiSi/p ⁺ -Si (B DS)/n-Si and NiSi/n ⁺ -Si (As DS)/p-Si are p-n or Schottky junctions. In this work, a dedicated circuit is devised to distinguish the type of as-fabricated NiSi/Si diodes with DS based on different switching mechanisms between p-n and Schottky junctions.

中文翻译：

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具有掺杂隔离（DS）的NiSi /p⁺-Si（n⁺-Si）/ n-Si（p-Si）二极管：pn结或肖特基结？

掺杂隔离（DS）技术已被广泛用于调整NiSi / Si二极管的肖特基势垒高度（SBHs），从而导致比接触电阻率降低（ $ \ rho _ {\ text {c}} $ ）在源极/漏极（S / D）欧姆接触中，或者在采用金属NiSi作为S / D的肖特基势垒S / D MOSFET（SB-MOSFET）中增强了电流驱动能力。电容-电压（ $ {C} $ – $ {V} $ ）方法通常用于可靠地提取NiSi / Si的SBH，以研究这种DS技术的有效性。为了避免大的反向泄漏电流，排除了在运行期间提取SBHs的可能性 $ {C} $ – $ {V} $ 在测量中，与外延硅衬底中极性相反的掺杂剂在NiSi / Si界面处偏析，例如，对于NiSi / n-Si，硼DS（B DS）；对于NiSi / p-Si，砷DS（As DS）。但是，这提出了一个关键问题，即NiSi / p ⁺ -Si（B DS）/ n-Si和NiSi / n ⁺ -Si（As DS）/ p-Si是pn结或肖特基结。在这项工作中，设计了专用电路，以基于pn和肖特基结之间的不同开关机制来区分带有DS的已制成NiSi / Si二极管的类型。