臺灣博碩士論文加值系統

為了解光和熱效應對於量子點之影響，本論文中將由硫化鋅包覆硒化鎘的量子點甲苯溶液混合二甲基矽氧烷，以兩種不同的封裝方式分別與底部含有四種不同發光強度的藍光發光二極體的標準5070封裝體結合。
量子點受到藍色波段的光激發出比較長波段的光，用積分球系統量測樣品的光譜圖隨著長時間供應電流來點亮發光二極體藍激發量子點的改變，並分析所有樣品光譜的半高寬、光強度大小以及峰值的位移量來確認是否會達到比較高的量子效率與可靠度。
因為量子點也會受到熱的影響所以我們還會使用熱影像儀拍攝持續點亮時整個樣品表面的溫度，來確保使用不同的封裝方式會提高樣品散熱以避免量子點快速老化，同時我們也會使用Comsol這個模擬軟體來模擬量子點在樣品內部的溫度分佈，將模擬與實際情形結合來對整個結果進行分析。

In this thesis, to understand the light and thermal impact on the quantum dots, the CdSe/ZnS quantum dot in toluene solution was mixed with polydimethylsiloxane and then filled on the LED. We designed two package structures to encapsulate quantum dots with two different quantities. Four different devices were made in 5070 lead frames respectively.
The quantum dots were excited by the blue light and they can release a longer wavelength of photons. The intensity degradation, emission peak shift, and the spectral linewidth broadening or narrowing are all monitored through continuous pumping of the LED chips co-packaged in the lead frame. The difference in thermal environment inside the package can greatly affect the outcomes of these parameters and the results are analyzed by linear extrapolation of the data points and also matched by the software simulation for the temperature distribution within the packages. Once these results are obtained, we can further optimize the thermal loading in the future to extend the lifetime of the quantum dots in this hybrid LED design.

摘要 i
Abstract ii
致謝 iii
List of Figures vi
Chapter 1. Introduction 1
1.1 Light Emitting Diode (LED) 1
1.2 Quantum Dots 2
1.3 Colloidal Quantum Dots 3
1.4 Motivation 4
Chapter 2. Theoretical Background and Literature Review 5
2.1 The Operation Principle of Light Emitting Diode (LED) 5
2.2 Literature Review of Quantum Dots 7
2.3 Emission Principle of Colloidal Quantum Dots 8
2.4 Type of Core-shell quantum dots 10
Chapter 3. Experiment and Measurement Setup 11
3.1 Experiment Materials 11
3.1.1 Colloidal quantum dots 11
3.1.2 Fabrication of Colloidal QD Light-Emitter Diode 12
3.2 Optical Measurement Instruments 14
3.2.1 Integrating Sphere 14
3.2.2 Thermographic Camera 15
3.2.3 Illuminometer 16
3.2.4 Absorption and Photoluminescence (PL) System 17
Chapter 4. The Hybrid Colloidal Quantum Dots LED Property and Reliability 18
4.1 The first Package type for hybrid CQD LED 18
4.2 A Metal Embedded Package Structure for hybrid CQD LED 19
4.3 Prepare of pumping source 21
4.4 The performance of two structures 22
4.5 Photoluminescence Quantum Yield 27
4.6 Peak and FWHM of hybrid CQD LED 32
Chapter 5. Thermal Effect Calculation 34
5.1 Measured thermal result of hybrid CQD LED 34
5.2 Thermal simulation of hybrid CQD LED 37
Chapter 6. Conclusion and Future Work 43
Reference 44

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