中 文 摘 要

近年來由於晶圓代工產品的多樣性及難以避免的待機時間之影響，所衍生之曝光條件的變動頻繁，因而導致半導體晶圓代工廠之微影製程技術，面臨透鏡加熱效應顯著的困擾，造成0.5μm多晶矽閘層的線寬控制不良。
本研究使用特性要因分析圖找出真正影響因素，並提出兩項改善對策，為應用調諧最佳化的透鏡加熱修正因子及開啟影像品質控制功能，以減低因透鏡加熱效應對線寬控制的衝擊，其中最佳化透鏡加熱修正因子，能夠有效控制同批產品中的透鏡加熱效應，而影像品質控制功能可以即時檢知焦距偏移，並補償次批產品的首片曝光條件，給予最佳曝光焦點，然後藉由最佳化的透鏡加熱修正因子，降低整批產品的透鏡加熱效應，兩者相輔相成，進而獲致穩定的線寬控制。
實驗結果證實將0.5μm多晶矽閘層的製程能力指標Cp/ Cpk，兩者皆由1.1提升至1.6，能有效降低透鏡加熱效應的影響，進而增進製程能力。

關鍵字：透鏡加熱效應、透鏡加熱修正因子、影像品質控制、微影製程

Abstract

Recently, due to varieties of foundry products and affections of unavoidable standby, exposure conditions alternate frequently. Therefore, photolithography in a semiconductor foundry fab. is facing confusion of lens heating effect, and unfavorable critical dimension control of 0.5μm poly gate.
This research is based on Cause and Effect Diagram to find out the root causes, and offer two improvement strategies. One is applying optimum lens heating correcting factor, and the other is executing image quality control（IQC）function, to reduce the lens heating effect of critical dimension （CD）control. In this case, optimum lens heating correcting factor can handle lens heating effect efficiently in the same batch of products. Image quality control（IQC）function can detect focus drift immediately, and provide best focus（BF）to compensate exposure condition for the next batch products, and reduce lens heating effect of whole batch by using optimum lens heating correcting factor. These two strategies complete each other, and acquire stable critical dimension control.
Experimental results verify that raising both photolithography ability indicator Cp/ Cpk of 0.5μm polycrystalline silicon floodgate layer from 1.1 to 1.6, can reduce the influence of lens heating effect effectively, and improve abilities.

Keywords: Photolithography, Lens Heating Effect, Image Quality Control.

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