李世光臺灣大學:應用力學研究所鄭琮達Cheng, Tsung-DarTsung-DarCheng2010-06-022018-06-292010-06-022018-06-292009U0001-0208200916025900http://ntur.lib.ntu.edu.tw//handle/246246/184850傳統光學系統受限於繞射極限，為了追求更小的聚焦光點，焦深將迅速縮小到接近一般試片的表面粗糙度。另一方面，Durnin在1987年首先提出無繞射光束的概念，此光束的焦深比一般透鏡聚焦光束大數十至數百倍。然而，其聚焦光點仍無法達到次微米甚至是次波長等級。 拜微機電技術進步之賜，次波長光學元件研究如雨後春筍般蓬勃發展。其中，表面電漿光學就是其中一例。本論文利用次波長結構結合表面電漿光學設計新型光學元件。文中提出結合金屬次波長結構與發光二極體產生長焦深次微米聚焦光點，以及利用銀和鎢的次波長圓環光學頭結合不同入射偏極態產生各種次波長無繞射光束，並提出一種新型貝索光束直寫儀，整合基礎物理研究以及光機設計，製作出具有超長焦深次波長光束，可應用於直接刻寫出高深寬比結構。 模擬方面提出了完整的模擬流程，包括利用嚴格耦合波理論快速估算出射光指向角，利用叢集電腦進行三維有限差分法模擬，並利用數值方法得到柱狀表面電漿子之色散曲線。模擬結果與實驗有良好的一致性。這些模擬不僅可幫助我們用來預測未知的物理現象，更可以提供我們設計的相關參數。 光機設計中，利用了電腦輔助設計軟體對結構進行配置與模擬，結合所設計之次波長圓環光學頭，產生次波長無繞射光束。為了達到自動化圖形刻寫，利用了圖形控制程式與被控元件整合，透過適當的校正流程，能夠使系統得到最佳的曝光效果。驗方面，我們使用倒立式顯微鏡觀測指向性出射的現象，並使用近場光學顯微鏡量測次波長圓環結構的近場及遠場特性。不但發現銀次波長圓環結構能夠依照不同的圓環材質與入射偏極態產生不同的類次波長無繞射光束，其出射光具有高穿透能量、次波長聚光點、及長焦深等特性。結合貝索光束直寫儀，成功地在AZP4620正光阻上製作出線寬為1 μm、深寬比達到5:1的高深寬比結構。Traditional optical systems are affected by diffraction limit which its focal spot size is limited by the incident wavelength and numerical aperture of the system. In 1987, Durnin and the coworkers firstly demonstrated the concept of nondiffracting beam which its depth of focus was larger than traditional Gaussian beam 10 to 100 times. However, the minimum spot size of nondiffracting beam still remained in the range of several microns. In thesis, we demonstrate the simulations and numerical calculations of beaming light from bull’s eye structure and SAA optical head. We also performed experiments to verify the optical properties and feasibilities of optical head continuously. A Bessel beam writer system which is integrated with SAA optical head is designed and performed the ability of fabricating high-aspect-ratio structure on photoresist. We examine the optical properties such as propagation modes, focal length, sidelobes, etc. of metallic sub-wavelength annular apertures (SAA) and use finite-difference time-domain (FDTD) simulation to compare our experimental findings. Using two different metals, silver and tungsten, we examine the different optical transmission properties of the two metallic SAA structures. The far-field propagation of the silver SAA structure is found to be a type of quasi-Bessel beam when compares with a quasi-Bessel beam generated by a perfect axicon. The propagation characteristics of these two beams were found to match qualitatively. The far-field transmitted light generated by the silver SAA structure is found to possess a 390 nm sub-micron focal spot with a 24 μm depth of focus, which is much smaller than the focal spot generated by a perfect axicon. We also find that a tungsten SAA structure can generate a sub-micron quasi-Mathieu beam. Utilizing radially polarized and azimuthally polarized beam, we can generate higher-order quasi-Bessel beam from SAAs. We use Bessel beam writer system to fabricate the high-aspect-ratio structure on AZP4620 positive photoresist with 1 μm line width and aspect ratio 5:1.ACKNOWLEDGEMENT IBSTRACT IIIBSTRACT (CHINESE) VABLE OF CONTENTS VIIIST OF FIGURES XIST OF TABLES XXHAPTER 1 INTRODUCTION 1.1 RESEARCH BACKGROUND 1.2 MOTIVATION 9.3 THESIS ORGANIZATION 10HAPTER 2 THEORY 13.1 SURFACE PLASMON PHOTONICS 13.1.1 Surface plasmon on a planer surface 13.1.2 Surface plasmon on a cylindrical surface 21.2 CYLINDRICAL VECTOR BEAMS 26.2.1 Laguerre-Gaussian modes 26.2.2 Radially and azimuthally polarized beams 29.3 NONDIFFRACTING BEAMS 33.3.1 Classification of nondiffracting beams 33.3.2 Mathieu beams 36.3.3 Bessel beams 41HAPTER 3 SIMULATIONS AND CALCULATIONS 44.1 SIMULATIONS OF BULL’S EYE STRUCTURE ON LIGHT EMITTING DIODE 49.2 SIMULATIONS OF NONDIFFRACTING BEAMS GENERATED BY SUB-WAVELENGTH SINGLE ANNULAR APERTURES 56.2.1 Sub-wavelength single annular apertures under linearly polarized light illumination 56.2.2 Sub-wavelength single annular apertures under radially and azimuthally polarized light illumination 72.2.3 Cylindrical surface plasmon dispersion relationship of silver SAA 83HAPTER 4 CONFIGURATION OF BESSEL BEAM WRITER SYSTEM 87.1 SYSTEM CONFIGURATION 88.2 SYSTEM ALIGNMENT 103HAPTER 5 EXPERIMENTAL RESULTS AND DISCUSSIONS 110.1 BEAMING LIGHT FROM BULL’S EYE STRUCTURE ON LIGHT EMITTING DIODE 110.2 NONDIFFRACTING BEAMS GENERATED BY SUB-WAVELENGTH SINGLE ANNULAR APERTURES UNDER LINEARLY POLARIZED LIGHT ILLUMINATION 117.2.1 Tungsten SAA under linearly polarized light illumination 118.2.2 Silver SAA under linearly polarized light illumination 126.3 NONDIFFRACTING BEAMS GENERATED BY SUB-WAVELENGTH SINGLE ANNULAR APERTURES UNDER RADIALLY AND AZIMUTHALLY POLARIZED LIGHT ILLUMINATION 139.4 FABRICATION OF HIGH-ASPECT-RATIO STRUCTURE BY USING BESSEL BEAM WRITER 151HAPTER 6 CONCLUSIONS AND FUTURE WORKS 160.1 CONCLUSIONS 160.2 FUTURE WORKS 161EFERENCE 164PPENDIX 172ITA 177application/pdf0 bytesapplication/pdfen-US無繞射光束奈米光學光學頭高深寬比結構貝索光束直寫儀nondiffracting beamnano opticsoptical headhigh-aspect-ratio structureBessel beam writerthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/184850/1/ntu-98-D94543003-1.pdf