針對高度微縮金氧半場效電晶體的參數精確萃取方法

Abstract

這篇論文主要列出幾種特別適合高度微縮之金氧半場效電晶體的新穎參數萃取方法。首先，三個關鍵製程參數（即是閘極多晶矽摻雜濃度、閘極氧化物物理厚度，以及通道摻雜濃度）能經由兩種方法的電容-電壓相符萃取出來：一種是Shrödinger-Poisson方程式解算以及另一種三角位能近似法。然後使用一種新的常數-遷移率方法萃取源極/汲極串聯電阻，此方法不像傳統方法般複雜，只需要對單一測試元件作簡單直流量測即可。我們進而能由改良的方法論達成定量地區別遮罩級通道長度跟冶金級通道長度。甚至源極/汲極擴張以及其摻雜濃度也能用邊緣直接穿隧技術萃取得。最終，通道中的載子遷移率以及臨界電壓都能直接準確地萃取出來。

This thesis mainly addresses several novel parameter extraction methods that are particularly suitable for highly scaled MOSFETs. First of all, the three key process parameters (namely, the gate polysilicon doping concentration, the gate oxide physical thickness, and the channel doping concentration) are extracted via C-V fitting by means of the two methods: one of the Shrödinger-Poisson equation solving and one of the triangular potential approximation. Then a new constant-mobility method is adopted to extract the source/drain series resistance Rsd, which, unlike the conventional counterparts, requires only simple DC measurements on a single test device. Once Rsd is extracted, we can quantitatively distinguish between the gate length at the mask level and the channel metallurgical length, which is achieved with the improved methodology. Even the source/drain extension and its doping concentration can be extracted using the edge direct tunneling technique. Finally, the carrier mobility in the channel, as well as the threshold voltage, can be straightforwardly extracted.