發光二極體(Lighting Emitting Diode, LED)具有體積小、反應時間短、低耗電、高可靠度、高壽命與符合環保等優點，而逐漸取代傳統照明。為因應LED照明之高亮度與高光通量之設計需求，除增進其光電轉換效率與加大晶片面積外，多顆LED發光模組亦是多數業者採用之方法。現今市面上之高功率LED燈泡多採用正裝(Face-Up)與倒裝(Flip Chip)構裝，正裝構裝因具有塑膠材料之導線架，不僅造成構裝自身熱傳性質不佳，更使發光角度受到限制，構裝尺寸也因此較大；相較之下倒裝構裝因不具有導線架結構，構裝尺寸較低，此外光學與熱傳性質也較正裝構裝優異，但相較正裝構裝其成本較昂貴。立華公司提出薄金屬構裝(Thin Metal Package,TMP)，其係透過特殊製程設計將導線架以薄金屬基板取代，此技術除了可降低成本外，又可縮小構裝尺並提升其光學與散熱效能。唯當薄金屬構裝應用於多晶片發光模組照明時，對於其熱傳與光學性質之了解尚嫌不足，仍待深入探討。
本論文主要係針對採薄金屬構裝技術之多顆LED模組燈泡進行散熱與光學效能之研究。首先應用計算流體力學(Computational Fluid Dynamics, CFD)套裝軟體SolidWorks Flow SimulationTM分析此顆創新設計之多顆LED模組燈泡的散熱效能，探討相關材料參數、幾何參數與環境溫度等重要影響因子對其晶片接面溫度(Junction Temperature)之影響，並據以降低LED燈泡之晶片接面溫度。在掌握其熱傳特性後，本論文接著進行數種可有效降低晶片接面溫度之散熱設計，除分析與評估其散熱效能外，並進行田口氏實驗設計(Taguchi Experimental Design)，前述所探討之重要影響因子與散熱設計皆納入考量。
為驗證本論文所建立之計算流體力學分析模型之有效性與準確性，本論文另分別使用紅外線熱像儀(IR Thermometer)與熱電偶(Thermalcouple)對本研究之LED燈泡進行表面溫度量測，並將量測結果與數值分析結果相互驗證。
最後，本論文亦使用光學分析軟體LightToolsTM對本研究之LED燈泡進行光學分析，並進行相關幾何結構與材料特性之參數化設計，以提升此LED燈泡之光學性能。為驗證光學分析之有效性，本論文另使用照度計對高功率LED燈泡進行照度量測，並將量測結果與光學分析結果相互比較。

Light Emitting Diodes (LEDs) have gradually replaced the traditional lighting device because of their many advantageous features, such as low power consumption, light weight, small size, and long life time. The requirement of high brightness and high luminous flux LEDs lighting can be met by increasing chip area and the electric-optical conversion efficiency and using multi-chip LED module. Up to date, face-up LEDs package and flip-chip LEDs package are widely used by most of the manufacturers. Compared with the face-up LEDs package, the flip chip one has better thermal and optical property and smaller size. However, the cost of the flip chip LEDs is higher than the face-up LEDs. Recently, a new LED package design, the so-called thin metal package (TMP), has been proposed, in which a thin metal substrate is used to replace the lead frame in conventional face-up LED package with by its novel process technology. This novel process technology can provide similar package size, thermal and optical performance at a lower cost compared with flip-chip LEDs package. As a new package technology, study on the TMP and application in multi-chip LEDs are still lacking.
In this work ,the thermal and optical performance of the high power LEDs light bulb developed by Leuktend Ltd. (Taiwan) using the TMP technology in natural convection are investigated through numerical modeling and experimental testing. In the numerical modeling, a three-dimensional (3D) computational fluid dynamics (CFD) analysis tool–SolidWorks Flow SimulationTM is applied for thermal characterization. Besides, a 3D optical engineering software LightToolTM is used to perform optical analysis. The numerical modeling is validated by the temperature and optical measurements using a thermal couple, an IR thermometer and a light meter. The thermal performance design guideline is sought through parametric analysis and Taguchi experimental design. Moreover, three different types of thermal-enhanced structural designs are proposed, and their thermal and optical performances are compared with each other.

[1]Alvin, C.; Chu, W.; Cheng, C. H. and Teng, J. T. (2011): Thermal Analysis of Extruded Aluminum Fin Heat Sink for LED Cooling Application, the 6th International Microsystems Packaging Assembly and Circuits Technology Conference (IMPACT), Taipei, Taiwan, pp. 397-400.
[2]Arik, M.; Becker, C. A.; Weaver, S. E. and Petroski J. (2003): Thermal Management of LEDs: Package to System, the 3rd International Conference on Solid State Lighting, San Diego, CA, U.S.A, pp. 64-75.
[3]Chen W. H.; Cheng H. C. and Shen H. A. (2003): An Effective Methodology for Thermal Characterization of Electronic Packaging, IEEE Transactions on Components and Packaging Technologies, Vol.26, No.1, pp. 222-232.
[4]Chen, W. H.; Cheng, H. C. and Lin, C. H. (2004a): On the Thermal Performance Characteristics of Three Dimensional Multichip Module, ASME Transactions, Journal of Electronic Packaging, Vol.126, pp. 374-383
[5]Cheng, H. C.; Chen, W. H. and Chung, I. C. (2004b): Integration of Simulation and Response Surface Method for Thermal Design of Multichip Modules, IEEE Transactions on Components and Packaging Technologies, Vol.27, No.2, pp. 359-372
[6]Dong, S. J.; Zhou, Q.; Wang, M. H.; Jiang, X. Q. and Yang, J. Y. (2011): Analysis of thermal spreading resistance in high power LED package and its design optimization, the 12th International Conference on Electronic Packaging Technology and High Density Packaging (ICEPT-HDP), Shanghai, China, pp. 1-5.
[7]EIA/JEDEC Standard (1995): Integrated Circuits Thermal Test Method Environment Conditions-Natural Convection (Still Air), EIA/JESD51-2.
[8]Goldsmid, H. J. (1960): Applications of the thermoelectricity, John Wiley & Sons, Inc.
[9]Jewett, J. W.; Serway, R. A. (2010): Physics for Scientists and Engineers with Modern Physics, Brooks Cole Inc.
[10]Juntunen, E.; Tapaninen, O.; Sitomaniemi, A.; Jamsa, M.; Heikkinen, V.; Karppinen, M. and Karioja, P. (2014): Copper-Core MCPCB with Thermal Vias for High-Power COB LED Modules, IEEE Transactions on Power Electronics, Vol.29, No.3, pp. 1410-1417.
[11]Kim, I.; Cho, S.; Jung, D.; Lee, C. R.; Kim, D. and Baek, B. J. (2013): Thermal Analysis of High Power LEDs on the MCPCB, Journal of Mechanical Science and Technology, Vol.27, No.5, pp. 1493-1499.
[12]Ma, Z., Wang, X., Zhu, D. and Liu, S. (2005): Thermal Analysis and Modeling of LED Array Integrated With an Innovative Liguid-cooling Module, the 6th International Conference on Electronic Packaging Technology (ICEPT), Shenzhen, China, pp. 1-4.
[13]Mills, A. F. (2005): Heat Transfer, Pearson Education, Inc.
[14]Munson, B. R., Young, D. F. and Okiishi, T. H. (1998): Fundamentals of Fluid Mechanics, John Wiely & Sons, Inc.
[15]Narendran, Y.; Gu, Y.; Freyssinier, J. P.; Yu, H. and Deng, L. (2004): Solid-State Lighting: Failure Analysis of White LEDs, Journal of Crystal Growth, Vol.268, No.3, pp. 449-456.
[16]Neuman, J. V.; Metropolis, N. and Ulam, S. (1949): The Monte Carlo Method, Journal of the American Statistical Association, Vol.44, No.247, pp.335-341.
[17]Petroski, J. (2004): Spacing of High-Brightness LEDs on Metal Substrate PCB’s for Proper Thermal Performance, the 9th Intersociety Conference on Thermal and Thermalmechanical Phenomena in Electronic Systems (ITHERM), Las Vegas, USA, pp. 507-514.
[18]Qin, P.; Li, Q. Q. and Cha, Y. C. (2011): Thermal Analysis of High Brightness Flip-chip LED Packages, the 13th Electronics Packaging Technology Conference (EPTC), Singapore, pp. 722-725.
[19]Retnasamy, V.; Sauli, Z.; Vairavan, R.; Taniselass, S. and Mamat, H. (2014): High Power LED Heat Dissipation Simulation Analysis via Heat Sink Fin Variation, the 11th IEEE International Conference on Semiconductor Electronics (ICSE), Kuala Lumpur, Malaysia, pp. 130-133.
[20]Tang, C. Y.; Tsai, M. Y.; Lin, C. C. and Chang, L. B. (2010): Thermal Measurements and Analysis of Flip-Chip LED Packages With and Without Underfills, the 5th International Microsystems Packaging Assembly and Circuits Technology Conference (IMPACT), Taipei, Taiwan, pp. 1-4.
[21]Vipradas, A.; Takawale, A.; Tripathi, S. and Swakul, V. (2012): A parametric Study of a Typical High Power LED Package to Enhance Overall Thermal Performance, the 13th Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), San Diego, CA, U.S.A, pp. 308-313.
[22]Wang, K.; Liu S.; Luo, X.; Liu, Z. Y. and Chen, F.(2008): Optical Analysis of A 3W Light-Emitting Diode MR16 Lamp, the 9th International Conference on Electronic Packaging Technology and High Density Packaging (ICEPT-HDP), Shanghai, China, pp. 1-5
[23]Yuan, L.; Liu, S.; Chen, M. and Luo, X. (2006): Thermal Analysis of High Power LED Array Packaging with Microchannel Cooler, the 7th International Conference on Electronic Packaging Technology (ICEPT), Shanghai, China, pp. 1-5.
[24]Zhong, D. N.; Zhang, J. (2011): Thermal and Optical Simulation of High-Power LED Array Based on Silicon Heatsink, International Conference on Electronics, Communications and Control (ICECC), Ningbo, China, pp. 4043-4046
[25]連韋翔,(2012): 白光LED陣列模組光學特性分析以及二次光學透鏡設計, 逢甲大學航太與系統工程學系碩士論文
[26]王焜雄,(2008): LED構裝溫度量測與熱傳分析, 國立清華大學動力機械工程學系碩士論文
[27]吳易信,(2014): 高功率LED水晶燈炮散熱與光學分析及設計, 逢甲大學航太與系統工程學系碩士論文
[28]呂姿穎,(2016): MOSFET功率模組散熱效能研究, 逢甲大學航太與系統工程學系碩士論文
[29]林佳筠,(2009): 發光二極體陣列構裝之熱傳與光學分析, 國立清華大學動力機械工程學系碩士論文
[30]李輝煌, (2000): 田口方法品質設計的原理與實務, 高立圖書有限公司