以表面電漿共振檢測奈米轉印充模缺陷與殘留層厚度

Using Surface Plasmon Resonance to Measure Filling Defects and Residual Layer Thickness in Nano-imprint Lithography

徐偉軒(Wei-Hsuan Hsu)

指導教授 ： 賀陳弘

國立清華大學/工學院/動力機械工程學系/博士(2012年)

摘要

微電子與積體電路的加工線寬與線距不斷縮小，其加工成本隨之大幅提升。在眾多奈米加工技術中，奈米轉印微影技術具有低成本及高產出率製作奈米級結構的優點，因此近年受到重視。
奈米轉印微影術是利用一奈米結構之模具接觸轉印材料並施加壓力，迫使轉印材料根據模具表面形貌而產生形變的一種加工技術。雖然此加工機制可輕易達成結構定義的目的，但容易因環境與製程參數變化而造成充模缺陷或殘留層厚度的改變。因此如何精確控制轉印結構品質，將是促進奈米轉印微影術發展的重要課題。
為了達成提升奈米轉印製程良率之目的，本研究應用表面電漿共振特性，設計一具有非破壞量測能力之轉印模具結構，藉此達成評估轉印結構品質的目的。在檢測過程中，所激發之表面電漿波可穿隧至模具轉印結構層，若模具與轉印材料間具有缺陷存在，表面電漿波共振之行為將受影響。另一方面，表面電漿波若可穿過轉印材料並進入基板，轉印結構的殘留層厚度也將影響表面電漿共振之特性。表面電漿共振特性之改變包含反射光譜外形的改變與共振角度之變化。因此藉由掃描反射光譜與評估共振角度，即可立即了解轉印結構品質之相關資訊。根據模擬與實驗結果，我們所研發之檢測方法可偵測到大於1.7%模穴體積之充模缺陷與8奈米之殘留層厚度。此檢測技術對於奈米轉印製程良率之提升將有直接的幫助。

關鍵字

奈米轉印 ； 充模缺陷 ； 非破壞檢測 ； 殘留層厚度 ； 表面電漿共振

並列摘要

When the dimension of the microelectronic structure decreases, high manufacturing cost is inevitable. A low-cost manufacturing technique for nanostructures is desired. Nano-imprint lithography (NIL) has the potential to meet the expectations. Nano-imprint lithography patterns the resist with physical deformation using a mold at nano-scale. However, the variation of environmental conditions and process parameters seriously affect the reproduction quality. To ensure the quality of the imprinted pattern is essential for industry.
In this study, the author applies the surface plasmon resonance (SPR) to develop a functional imprinting mold, which has non-destructive measurement capability for the quality of the imprinted pattern. During measuring process, the excited surface plasmon can penetrate into the interface between mold surface and imprinted material. If there is filling defects in the interface, the SPR behavior will be affected, including the reflectivity spectrum change and resonance angle shift. If the penetration of surface plasmon can reach the substrate, the thickness of residual layer also affects the SPR behavior. Based on the reflectivity spectrum curve and resonance angle, the quality of the imprinted pattern can be told. According to the simulation and experimental results, the developed system can detect the filling defects as low as 1.7 % of the volume of the mold cavity and 8 nm residual layer thickness. This new application of SPR promises to improve NIL performance in the nanofabrication industry.

並列關鍵字

Nano-imprint ； Filling Defects ； Non-destructive Measurement ； Residual Layer Thickness ； Surface Plasmon Resonance (SPR)

參考文獻

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