為了確認多層介電層界面對閾值電壓的影響，在介面氧離子擴散的理論基礎下，此論文通過應用反應力場（ReaxFF）的分子動力學（MD）模擬研究了平面以及閘極全環（GAA）結構中介電層之間原子的熱動力學和相互擴散，並通過電負度及表面能的計算來證明它。基於原子分佈，在介電層界面處以一維柏松方程式計算內建電場和電勢。研究顯示，氧原子會在介電層界面擴散並形成偶極層，其產生之內建電位取決於矽納米線（NW）的直徑，並與內外表面能量的特徵有關。

In order to confirm the effact of the interface of the multilayer dielectric layer on the threshold voltage, based on the theory of interface oxygen ion diffusion, this study investigates the thermal dynamics and inter-diffusion of atoms between dielectrics in a gate-all-around (GAA) structure by means of Reactive force field (ReaxFF) applied molecular dynamics (MD) simulations and prove it through the electronic negativity calculation of surface energy. Based on the atomic distribution, the built-in electric field and potential are calculated by Poisson equation at the dielectric interface. We show that the build-in potential is dependent on the diameter of the Silicon nanowire (NW) and it is related to the feature of inner and outer surface energy.

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