電漿離子能量分佈量測技術

Diagnostic Technology for Plasma Ion Energy Distribution

張家豪 ； 蘇郁仁 ； 黃威

《機械工業雜誌》 475期 (2022/10) Pp. 45-53

摘要

現代半導體元件製造過程中，舉凡電漿蝕刻（plasma etch）、電漿輔助化學氣相沉積（PECVD）、物理氣相沉積（PVD）等電漿相關製程均扮演極為重要的角色。如何提升製程良率及產量，成為製造商彼此間相互競爭的重點開發項目，也是設備廠商所需面對的課題之一。而隨著半導體元件尺寸不斷縮小，使用材料多元化，對於製程技術與設備開發所面臨的挑戰也就更加嚴苛，唯有深入了解製程腔體中電漿特性參數，才能夠掌握製程反應機制與結果。而電漿蝕刻製程中離子能量大小對製程結果，諸如蝕刻率、蝕刻選擇比及表面輪廓控制等，都有顯著的影響。本文將針對離子能量分佈（Ion Energy Distribution, IED）量測方法進行介紹。

關鍵字

電漿量測 ； 離子能量分佈 ； 柵極式離子能量分析儀

並列摘要

In modern semiconductor device manufacturing industry, the plasma processing plays a crucial role in processes such as dry etching, plasma-enhanced chemical vapor deposition (PECVD) and physical vapor deposition (PVD), etc.; whereas high yield and high throughput are of primary important challenge for the semiconductor manufacturers to breakthrough and to enhance competitiveness. As the semiconductor device sizes decrease to nanoscale and new semiconductor materials emerge, it is more difficult to develop an advanced manufacturing process and equipment. It is desirable to diagnose the plasma properties to understand plasma mechanism in depth, in order to improve process stability and reliability. In a plasma processing, the energy of bombarding ions critically controls the surface reactions. Especially in etching process, the ion energy is typically controlled coarsely with a sinusoidal bias voltage applied to the substrate electrode, producing a broad bimodal ion energy distribution (IED), which influences the etch rate, selectivity and surface profile, etc. In this article, an ion energy distribution diagnostic technology will be introduced.

並列關鍵字

Plasma diagnostic ； Ion energy distribution ； Gridded ion energy analyzer

參考文獻

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