射頻電容耦合電漿（RF-CCP）反應器廣泛應用於半導體工業之蝕刻製程。蝕刻的選擇性、非等向性與表面損傷皆主要由晶圓表面的離子能譜決定。該能譜由鞘層動力學所形塑。鞘層動力學的直接量測在實驗上有其困難。另一方面，自洽的動力學模擬為標準的研究途徑。
本研究採一維靜電式粒子網格法（PIC）模擬對稱式 RF-CCP 放電，在無碰撞模型下進行，工作氣體為氬氣。數值方法採用教科書式的顯式蛙跳法（leapfrog）推進電漿粒子，利用 CIC 演算法進行密度的線性權重分配，並以基於三對角矩陣方程的 Poisson 求解器解出電位分布。鞘層電位將電子侷限於電漿主體內。在穩態下，電子流向牆面的損失可忽略。在本數值模擬中，抵達牆面的離子經再注入以維持固定的離子數量。
模擬呈現穩態的電漿電位結構，以及自洽形成的鞘層，並對牆面的離子能譜進行分析。本論文亦提供了在無碰撞條件下，由鞘層主導加熱機制的一個參考基準。

The radio-frequency capacitively coupled plasma (RF-CCP) reactors are widely used in industrial semiconductor etching processes. Selectivity, anisotropy, and surface damage are determined primarily by the ion energy spectra at the wafer surface. The spectra are shaped by the dynamics of the wall sheath. Direct measurement of sheath dynamics is experimentally difficult. Alternatively, a self-consistent kinetic simulation is the standard approach.
A one-dimensional electrostatic Particle-in-Cell (PIC) simulation of a symmetric RF-CCP discharge is implemented in the collisionless limit, with argon as the working gas. The numerical method follows the textbook-type explicit leapfrog pusher with Cloud-in-Cell (CIC) weighting and a Poisson solver based on a tridiagonal matrix equation. The sheath potential confines electrons to the bulk plasma. In the steady state, the electron loss to the wall is negligible. In our numerical simulation, ions that reach the wall are re-injected to maintain a constant ion number.
The simulation shows the steady-state plasma potential structure and the self-consistent sheath formation. The ion energy spectra at the wall are characterized. This thesis also provides a self-consistent reference for the sheath-dominated heating channel in the collisionless condition.

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