摘要(英) |
Abstract
LED (Lighting Emitting Diode) is a kind of solid cold light source, which is the fourth generation lighting source after filament lamp, fluorescent lamp and high pressure sodium lamp. It has been widely applied in lighting and backlight field due to its advantages, such as energy conservation and environmental protection, high LE, fast response, small volume, light weight, and long life span, etc. QDLED (Quantum Dots Light-Emitting Diode) is a new luminescent device that packages quantum dots in LED, in which quantum dot is a new light conversion material, featuring adjustable spectrum, narrow half-wave width, and high quantum yield, etc. It can enable QDLED to show lights of high color rendering index, high saturation and wide color gamut, becoming an upsurge in research and application in the lighting and backlight field in recent years.
The contents of this paper are as follows:
(1) The principle of the quantum dot phosphors and the advantages of the relatively traditional LED were introduced, the research status of the quantum dot phosphors and their packaging were summarized, the key challenges in the material and packaging field were stated and the ways to improve the performance and find the most matching packaging structure were explored.
(2) Optimization of the packaging structure of the quantum dot phosphors. Five packaging structures: air gap type, silicon lens type, silicon filling type, glass gap type and sulfur resistance coating type were packaged and compared. Aiming at obtaining a packaging structure with lowest temperature and highest thermal stability and reliability, we found that the glass gap type was the most matching one. Compared with the traditional silicon filling type packaging, the light efficiency of the glass gap type was fairly consistent. When the glass gap type was lit at the current of 300mA, its highest temperature was 27.9℃, while it’s 29.9℃ for the silicon filling type. It was 40.8% lower than the silicon filling type in the temperature rise of the quantum dot fluorescent diaphragm. Its luminance maintenance rate was 5.6% and 3.5% higher than the silicon filling type in the wet high temperature operating life (WHTOL) and the high temperature operating life (HTOL) experiments respectively, and 41.4% higher especially in terms of the sulfur resistance.
In this experiment, a packaging structure with the lowest temperature and highest reliability was obtained, and it was consistent with the verification results of the heat calculation. It provides a feasible packaging thought for the quantum dot phosphor. |
參考文獻 |
參考文獻
[1] X. Michalet, F. F. Pinaud, L. A. Bentolila, J. M. Tsay, S. Doose, J. J. Li, G. Sundaresan, A. M. Wu, S. S. Gambhir, and S. Weiss, Quantum Dots for Live Cells, in Vivo Imaging, and Diagnostics. Science, 2005, 307:538-544
[2] Chen O, Wei H, Maurice A, et al. Pure colors from core-shell quantum dots. MRS Bull, 2013, 38:696–702
[3] http://m.elecfans.com/article/689386.html
[4] Talapin D V, Steckel J. Quantum dot light-emitting devices. MRS Bull, 2013, 38:685–695
[5] Rogach A L, Talapin D V, Shevchenko E V, et al. Organization of matter on different size scales: Monodisperse nanocrystals and their superstructures. Adv Funct Mater, 2002, 12: 653–664
[6] http://tv.zol.com.cn/598/5989419.html
[7] Kwak J, Bae W K, Lee D, et al. Bright and efficient full-color colloidal quantum dot light-emitting diodes using an inverted device structure. Nano Lett, 2012, 12:2362–2366
[8] Cho K S, Lee E K, Joo W J, et al. High-performance crosslinked colloidal quantum-dot light-emitting diodes. Nat Photon, 2009, 3: 341–345
[9]YAM F K,HASSAN Z.,Innovative advances in LED Technology, [J].Microelectron J, 2005, 36:129-137.
[10] Wonkeun Chung, Kwanhwi Park, Hong Jeong Yu, Jihyun Kim, Byung-Hee Chun, Sung Hyun Kim, et al. White emission using mixtures of Cd Se quantum dots and PMMA as a phosphor, Optical Materials 32, 2010, 515–521.
[11] Xiebing Wang, Wanwan Li and Kang Sun.Stable efficient Cd Se/Cd S/Zn S core/multi-shell nanophosphors fabricated through a phosphine-free route for white light-emitting-diodes with high color rendering properties, J. Mater. Chem, 2011, 21, 8558–8565.
[12] Xuefeng Peng,et al. Low-cost and high-color-quality white light emitting diodes based on Cd Se/Zn S quantum dots. Journal of Optics, 2015, 44:249-254.
[13] Woo-Seuk Song and Heesun Yang,Efficient White-Light-Emitting Diodes Fabricated from Highly Fluoscent Copper Indium Sulfide Core/Shell Quantum Dots,Chem.Mater. 2012, 24, 1961−1967.
[14] Jong-Hoon Kim and Heesun Yang,White lighting device from composite films embedded with hydrophilic Cu(In,Ga)S2/Zn S and hydrophobic In P/Zn S quantum dots,Nanotechnology 25, 2014, 225601.
[15] Wonkeun Chung, Hyunchul Jung, et al. Fabrication of high color rendering index white LED using Cd-free wavelength tunable Zn doped Cu In S2 nanocrystals, 22 October 2012 / Vol. 20, No. 22 / OPTICS EXPRESS 25071.
[16] Woo-Seuk Song,Eun-Pyo Jang, et al. Unique oxide overcoating of Cu In S2/Zn S core/shell quantum dots with Zn Ga2O4for fabrication of white light-emitting diode with improved operational stability,J Nanopart Res, 2013, 15:1462.
[17] Bingkun Chen,1,2 Qingchao Zhou , et al. Red emissive Cu In S2-based nanocrystals: a potential phosphor for warm white lightemitting diodes,22 April 2013 | Vol. 21, No. 8 | DOI:10.1364/OE.21.010105 | OPTICS EXPRESS 10106.
[18] Zhuolei Zhang,Dong Liu, et al. Dual Emissive Cu:In P/Zn S/In P/Zn S Nanocrystals: Single-Source“Greener”Emitters with Flexibly Tunable Emission from Visible to Near-Infrared and Their Application in White Light-Emitting Diodes,Chem. Mater. 2015, 27, 1405−1411.
[19]Sun-Hyoung Lee, Ki-Heon Lee, et al. Remote-type, high-color gamut white lightemitting diode based on In P quantum dot color converters,OPTICAL MATERIALS EXPRESS 1297.2014, Vol. 4, No. 7.
[20] Woo,J. Y., Kim,K., Jeong,S., et al. Enhanced photoluminance of layered quantum dot-phosphor nanocomposites as converting materials for light emitting diodes. The Journal of Physical Chemistry C. 2011, 115(43):20945-20952.
[21] Erdem,T., Nizamoglu,S., Demir H V. Computational study of power conversion and luminous efficiency performance for semiconductor quantum dot nanophosphors on light-emitting diodes. Optics express. 2012, 20(3):3275-3295.
[22] Lei,Xiang., Zheng,Huai., Guo,Xing., et al. Optical Performance Enhancement of Quantum Dot-Based Light-Emitting Diodes Through an Optimized Remote Structure. IEEE Transactions On Electron Devices. 2016, 63(2):691-697.
[23] Park.J.K., Lim.M.A., Kim.C.H., et al. White light-emitting diodes of Ga N-based Sr2Si O4: Eu and the luminescent properties [J]. Jpn. Appl. Phys. Lett. 2003, 82(5):683-685
[24] 陳學仕,量子點簡介,化工資訊 ChemNet 奈米專欄,Sep. 2002
[25] Kim J H, Song W S, Yang H. Color-converting bilayered composite plate of quantum-dot–polymer for high-color rendering white light-emitting diode. Opt Lett, 2013, 38: 2885–2888
[26] Kim J H, Yang H. White lighting device from composite films embedded with hydrophilic Cu (In, Ga) S2/ZnS and hydrophobic InP/ZnS quantum dots. Nanotechnology, 2014, 25: 801–811
[27] Unnithan A R, Barakat N A M, Abadir M F, et al. Novel Cd Pd S/PVAc core-shell nanofibers as an effective photocatalyst for organic pollutants degradation. J Mol Catal A: Chem, 2012, 363: 186–194
[28] Wu Y, Bao B, Su B, et al. Directed growth of calcein/nile red coaxial nanowire arrays via a two-step dip-coating approach. J Mater Chem A, 2013, 1: 8581–8586
[29] Kakati J, Datta P. On characteristics of PVA/Cd S and PVA/Cd S: Cu nanocomposites for applications as LED. J Lumin, 2013, 138: 25–31
[30] Fragouli D, Resta V, Pompa P P, et al. Patterned structures of in situ size controlled Cd S nanocrystals in a polymer matrix under UV ir-radiation. Nanotechnology, 2009, 20: 472–476
[31] Kharazmi A, Saion E, Faraji N, et al. Optical properties of CdS/PVA nanocomposite films synthesized using the gam-ma-irradiation-induced method. Chin Phys Lett, 2013, 30: 57803–57807
[32] Li Y, Zhang W, Li K, et al. Oxidative dissolution of polymer-coated Cd Se/Zn S quantum dots under UV irradiation: Mechanisms and ki-netics. Environ Pollut, 2012, 164: 259–266
[33] Chu M, Zhou L, Song X, et al. Incorporating quantum dots into polymer microspheres via a spray-drying and thermal-denaturizing ap-proach. Nanotechnology, 2006, 17: 1791–1796
[34] Sato M, Kawata A, Morito S, et al. Preparation and properties of polymer/zinc oxide nanocomposites using functionalized zinc oxide quantum dots. Euro Polymer J, 2008, 44: 3430–3438
[35] Yoon C, Hong H G, Kim H C, et al. High luminescence efficiency white light emitting diodes based on surface functionalized quantum dots dispersed in polymer matrices. Colloids Surf A: CPEAEH, 2013, 428: 86–91
[36] Yoon H C, Oh J H, Do Y R. High color rendering index of remote-type white LEDs with multi-layered quantum dot-phosphor films and short-wavelength pass dichroic filters. Int Soc Opt Photon, 2014 : 919013
[37] 朱永明,謝斌,羅小兵,量子點轉化 LED 封裝的進展與展望,科學通報,2017,第 62 卷 第 7 期:659 ~ 673
[38]https://web.archive.org/web/20080915133126/http://www.saltlakemetals.com/Silver_Sulfide.htm
[39] Xu, Xiaoyou; Ray, Robert; Gu, Yunlong; Ploehn, Harry J.; Gearheart, Latha; Raker, Kyle; Scrivens, Walter A. "Electrophoretic Analysis and Purification of Fluorescent Single-Walled Carbon Nanotube Fragments". Journal of the American Chemical Society. 2004, 126 (40): 12736–7.
[40] Lim, Shi Ying; Shen, Wei; Gao, Zhiqiang. "Carbon quantum dots and their applications". Chemical Society Reviews. 2015, 44 (1): 362–81. |