近年來，極紫外光是半導體製程中非常重要的光源，其可以提升半導體光微影技術的解析度。使用雷射加熱靶材的方式產生極紫外光，會有較高的轉換效率，因此成為了熱門的研究對象。由於雷射激發靶材產生極紫外光的過程太過複雜且實驗測試的費用太高，我們使用程式模擬來了解物理特性與該使用哪些參數去提升轉換效率。基於過去的研究指出，與單一脈衝相比，使用雙脈衝雷射加熱靶材可以更有效的提升極紫外光的轉換效率。希望由本次研究可以更進一步去釐清雙脈衝雷射產生極紫外光系統中，各種雷射參數與延遲時間對轉換效率的影響。最後，在主要脈衝參數給定的情況下，我們可以由模擬給出最佳化轉換效率的預脈衝能量，再由我們計算出的通用經驗公式，決定出適合的預脈衝寬度與其對應的強度與延遲時間。

In recent years, extreme ultraviolet light is a very important light source in the semiconductor process, which can enhance the resolution of semiconductor light lithography technology. Research for the extreme ultraviolet light sources based on laser-produced plasma become popular, due to its high conversion efficiency. The laser-produced plasma system is too expensive to test experimental parameters, so we use numerical simulations to understand the physical properties and which parameters to use to improve conversion efficiency. Previous studies have shown that the use of dual-pulse laser system can enhance the conversion efficiency more effectively compared to the single pulse system. The influences of pre-pulse parameters, main pulse parameters and delay time on EUV conversion efficiency characteristics were discussed in the paper. Our results show that we can use the universal empirical formula to determine the optimized parameters of pre-pulse under knowing main-pulse information.

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