高靈敏度電漿子混成模態金奈米天線感測器與新穎電漿子材料製程

Abstract

本論文研究金奈米天線(Gold Nanoantenna)電漿子混成模態(Plasmon Hybridization Mode)在感測器之應用，以及新穎電漿子材料-氮化鈦薄膜與奈米結構的製程。金奈米天線透過有限元素法(Finite Element Method)模擬、電子束微影(E‐beam Lithography)製作樣品並驗證電漿子混成模態的光學特性。相較於在正向入射下的鍵結模態(Bonding Mode)，稜鏡耦合的方式不僅可以將入射光能量轉移至奈米天線的電漿子共振，具高消光係數之反鍵結模態(Antibonding Mode)對於改變周遭折射率亦有高的靈敏度，模擬與實驗提供了金奈米天線之反鍵結模態應用於感測器的解釋與驗證。反鍵結模態共振之總電場為鍵結模態共振之2.32倍，而金奈米天線之反鍵結模態共振下的優質係數(Figure of merit, FOM)為鍵結模態之4.84倍。本論文另一部分的研究，針對氮化鈦(Titanium Nitride, TiN)來開發可應用在可見光與近紅外光波段的新穎電漿子材料，使用多靶磁控共濺鍍系統(Multi‐target Co‐sputtering System)搭配高功率脈衝磁控濺鍍技術(High Power Impulse Magnetron Sputtering)與非平衡濺鍍(Unbalance Magnetron Sputtering)製備符合電漿子特性之氮化鈦薄膜，以氮化鈦為電漿子材料之一維與二維週期性結構預期在未來可以實現。

This thesis includes the plasmon hybridization modes of gold nanoantenna in evanescent waves and fabrication of novel plasmonic materials: titanium nitride. According to simulation and experiment, plasmonic antibonding mode of gold symmetric nanoantennas is observed in evanescent waves. Comparing with the bonding mode for normal incidence, the use of prism coupling to transfer the energy of incident light to plasmonic resonance in nanoantennas not only has a higher extinction coefficient but also achieves higher sensitivity to the surrounding environment. Near‐ and far‐field analysis was given fully explanation and verification of capability for chemical sensing application. The total electric field of antibonding‐mode resonance is 2.32 times higher than bonding‐mode resonance. The sensitivity of the antibonding mode of gold nanoantenna is 4.84 times that of the bonding mode in terms of the figure of merit. Titanium nitride (TiN) had been reported as an alternative plasmonic material in visible and near‐infrared region. In the second part of the thesis, the multi‐target magnetron co‐sputtering system with combined high power impulse magnetron sputtering (HIPMIS) and unbalance magnetron sputtering (UBMS) technique is used to fabricate TiN thin film. The optimization processing condition as well as optical characterization of TiN is introduced. The one‐ and two‐dimensional periodic TiN‐based nanostructures are expected plamonic application in the future work.