奈米尺寸金氧半場效電晶體通道背向散射:蒙地卡羅模擬與物理模型

Abstract

藉由散射矩陣的方法，可以推導出背向散射係數，再利用蒙地卡羅模擬証明。組成背向散射係數的兩個重要的參數─ kBT layer的寬度和平均自由路徑─也在論文中有進一步地討論；kBT layer的寬度的物理解析式模型建立在源極到通道上假設的拋物線能障上，也藉由實驗以及蒙地卡羅模擬得到驗證。藉由蒙地卡羅模擬得到在入射處的速度分佈推斷平均自由路徑的縮短源自於載子熱效應，然而在拋物線能障的情況下因為沒有熱載子效應，使得平均自由路徑維持定值。

Through the scattering matrix approach, the backscattering coefficient is derived and it is verified by Monte Carlo simulations. Two important parameters, kBT layer's width and mean-free-path, constituting the channel backscattering have been taken into account. A parabolic barrier oriented compact model has been physically derived for kBT layer's width. The validity of this compact model has been corroborated experimentally and by Monte Carlo simulation results. As for mean-free-path, the carrier heating as the origin of reduced mean-free-path is inferred on the basis of the simulated carrier velocity distribution at the injection point. Strikingly, for the parabolic potential case, the mean-free-paths remain consistent: apparent mean-free-path = mean-free-path. This indicates the absence or weakening of the carrier heating in the layer of interest, valid only for a parabolic potential barrier