Analytical Subthreshold Behavior Model for Symmetrical Tri-Material Gate Stack Double-Gate MOSFETs

有關參材質對稱堆疊雙閘極金氧半場效電晶體之次臨界行為解析模型研究

本研究由帕森方程式之全二維的解推導出一系列全新與連續之有關參材質對稱堆疊雙閘極金氧半場效電晶體之次臨界行為的解析式。與傳統型金氧半場效電晶體比較而言；敝人所提出之參材質對稱堆疊雙閘極金氧半場效電晶體之電位分佈、短通道臨界電壓衰變、次臨界斜率、汲極牽引電位屏障降低現象，均無須任何經驗參數函數之修正、且更可改善直接穿隧效應以及有效抑制邊緣導致能帶下降效應與降低熱載子效應。另外，我們進一步藉由元件模擬器之驗證，證實本二維完整之次臨界方程式可以適用於參材質對稱堆疊雙閘極金氧半場效電晶體。本二維完整之次臨界方程式不僅提供參材質對稱堆疊雙閘極金氧半場效電晶體元件特性之物理解釋，並且基於有效之演算，可以被應用於電路模擬器中之元件模型建立，且符合記憶體之電路模擬與設計需求。

Based on resultant solution of two-dimensional (2-D) Poisson’s equation in the subthreshold regime, an analytical model consisting of two-dimensional potential, threshold voltage, subthreshold current and subthreshold swing for the fully depleted symmetrical tri-material gate stack double-gate (STMGSDG) MOSFET has been developed. The model is verified in good agreement with numerical simulation results over a wide range of the device parameters. The model not only offers the physical insight into device physics but also provides the basic designing guidance for the device.