Summary: | 碩士 === 國立臺灣海洋大學 === 光電科學研究所 === 98 === In the thesis, we introduce the development and the basic theory of surface plasmon (SP). In the experiment, Ag nanoparticle arrays were fabricated on InGaN/GaN multiple quantum wells (MQWs) by two different methods successfully. The fabrication techniques for Ag nanoparticle arrays are nanosphere lithography (NSL) with reactive ion etching (RIE) and oblique angle deposition (OAD). Photoluminescence (PL) and time-resolved photoluminescence (TRPL) of the samples were measured. We demonstrate that higher PL intensity of MQWs decorated with Ag nanoparticles array fabricated with NSL can be achieved, as compared to that of bare MQWs. This is contributed to the improvement of light extraction due to the coupling of MQWs with localized surface plasmons (LSPs), which are generated between Ag nanoparticles array. We try to find out optimal parameters of Ag nanoparticle size. By comparing the Ag nanoparticle of different sizes in PL spectra of MQWs, smaller Ag nanoparticles result in higher PL in intensity. We observe the maximum PL enhancement is 2.92 when the size of nanosphere is 300nm in diameter and Ag film 70nm in thickness on the MQWs. Higher PL intensity of MQWs decorated with Ag nanoparticles array fabricated with OAD can also be achieved, as compared to that of bare MQWs. The maximum PL enhancement is 4.78 when the thickness of Ag film and length of Ag nanorod are 70nm and 10nm, respectively. The results obtained show the feasibility of plasmon-assisted MQWs emission enhancement.
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