在半導體製程下，電漿蝕刻的探討是一個很普遍的課題，然而在大部分的研究裡，很少看到以模擬的方式去探討電漿蝕刻在二維渠溝下的行為。因此，本研究以粒子網格法(PIC)建構一維以及二維空間電漿行為之模型。首先先以一維模型模擬電容耦合電漿在兩電極板間之行為，觀察電漿鞘層的形成，並且探討由電子撞擊兩極板產生的二次電子所造成的影響。更進一步拓展PIC模型至二維電漿蝕刻渠溝下之行為，藉由改變渠溝的寬度，探討乾式蝕刻的非等向性。為了使情況更加貼近真實，在模擬中我們加入射頻偏壓來符合實際情況。此外，在電漿蝕刻時，渠溝底部有可能會因為離子不斷轟擊而帶正電，因此，我們也在渠溝底部加入了正電位的邊界條件來探討其對電漿蝕刻非等向性的影響。

For an efficient etching by plasma, in generating trench geometries, anisotropy is an important factor. For the ions to perpendicularly bombard the semiconductor surface, stationary plasma sheaths need to be formed to accelerate the ions. However, not many journal publications have reported on the stability of a plasma in a multi-dimensional trench geometry. A Particle-in-Cell model is built solely from the beginning in Fortran 95 to investigate basic plasma interaction between two electrode plates including ions and electrons. A secondary electron emission (SEE) effect in one-dimensional PIC model is incorporated. Then, our PIC model is extend to a two-dimensional trench geometry. The plasma behavior in the vicinity of the trench geometry is investigated by varying its size. In this study, radio frequency (RF) electric potential is employed in the system as in capacitively coupled plasma (CCP) process widely used in the plasma etching process. Furthermore, the influence of charging up by ions’ bombardment, which results in a positive potential on the trench bottom, is also examined.

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