本研究主要觀察單顆微米介電圓盤經由雷射光照射後，所產生光子奈米噴流之現象。由二氧化矽與氮化矽兩種微米圓盤，分別以紅光(671nm)、綠光(532nm)及藍光(405nm)三種不同波段之雷射光進行照射。本研究主要可分為理論分析及實驗量測兩部分進行探討。在理論方面，利用時域有限差分法，分別對不同微米圓盤尺寸大小、不同微盤折射率、不同入射光波長及不同環境折射率進行模擬，並且分析微米圓盤所產生的光子奈米噴流之光場分佈和光場強度及影響光子奈米噴流形成的相關參數。在實驗方面，可以細分為兩部分，第一部分為晶圓製程以及第二部分晶圓量測及分析，利用台灣大學工學院奈米機電系統研究中心進行加工處理，再使用本實驗室設計一套高感光的光學顯微鏡來觀察微米圓盤所產生的光子奈米噴流，分別照射在直徑3μm、5μm、8μm、10μ和15μm的微米圓盤上，並分析光子奈米噴流其焦距、半高全寛及衰減長度與微米圓盤直徑的關係。氮化矽微盤中特別改變環境折射率至1.518，使得光子奈米噴流現象能產生於微盤外側。最後，將本實驗數據及理論分析進行相互驗證，發現實驗數據的趨勢與理論分析相同。當微盤受到雷射光照射，會產生一個低發散的光點，此光子奈米噴流有著光點遠小於入射光波長且能量集中的特性，本論文研究結果有助於解決高科技產業中奈米等級影像量測的問題。 The photonic nanojet in single dielectric microdisk illuminated by a laser source is studied. We fabricated the SiO2 and Si3N4 microdisks at different diameters. The laser of wavelength 671 nm, 532 nm, and 405 nm is used to be a light source for dielectric microdisk. In numerical simulation, the finite-difference time-domain method is used to execute the calculations for the intensity distribution of photonic nanojet in the dielectric microdisks. In experiment, the dielectric microdisks are made by using semiconductor manufacturing technology. The measurement of photonic nanojet is performed with a high sensitivity optical microscope system. The photonic nanojets are observed from the collected images for microdisks of 3 μm, 5 μm, and 8 μm diameters. The influences of focal length, full width at half maximum, and decay length on the disk diameters are presented. The refractive index becomes 1.518 when the disks are immersed in oil. This makes photonic nanojets appear on the outside of microdisk. In conclusion, the experiment and the numerical simulation are in agreement. A low divergence spot appears when the microdisk is illuminated by laser beam. The full width at half maximum of spot is much smaller than the incident wavelength, and the energy is concentrated. The study will help to solve the problems of nano-scale image measurement in high technology industry.
