成功大學博碩士論文系統

簡易檢索 / 詳目顯示

回結果列表

研究生：	武黃俊 Vu, Hoang-Tuan
論文名稱：	硒化鎘@硫化鋅/硫化鋅巨型量子點發光二極體之研製 Investigation and Fabrication of CdSe@ZnS/ZnS Giant Quantum Dot Light-Emitting Diodes
指導教授：	蘇炎坤 Su, Yan-Kuin
學位類別：	博士 Doctor
系所名稱：	電機資訊學院 - 微電子工程研究所 Institute of Microelectronics
論文出版年：	2016
畢業學年度：	105
語文別：	英文
論文頁數：	129
中文關鍵詞：	量子點發光二極體、量子點、CsN3 、sMoOx 、巨型、热稳定性、載子控制層
外文關鍵詞：	Quantum dots, quantum dot light-emitting diodes, QDs, QLEDs, giant QDs, charge control layer, sMoOx, cesium azide, thermal stability
相關次數：	點閱：101 下載：6
分享至:	分享至facebook 分享至twitter

查詢本校圖書館目錄查詢臺灣博碩士論文知識加值系統勘誤回報

本篇論文，致力於研究由有機電子與電洞傳輸層以及巨型量子點發光層所建構的第二型態量子點發光二極體(QLED)。藉由比較漸變核心厚殼硒化鎘@硫化鋅/硫化鋅 (CdSe@ZnS/ZnS) 量子點、漸變核心無殼硒化鎘@硫化鋅 (CdSe@ZnS)量子點和薄殼硒化鎘/硫化鋅 (CdSe/ZnS) 量子點，可發現巨型量子點的優勢明顯表現在電致發光元件上。具有較大粒子尺寸的厚殼量子點可減少表面缺陷，降低量子點電荷效應，抑制歐傑復合與非輻射能量傳輸。最終我們得到一個電流效率2.16 cd/A (@ 9 V) 以及最大亮度8200 cd/m2 (@ 15 V) 的電致發光元件。
本論文的第二部分，使用CsN3作為電子注入層，與使用LiF作為電子注入層的元件進行比較，無論是紅光、綠光還是藍光元件皆表現出兩倍以上的效能提升。進一步比較使用CsN3、CsF、Cs2CO3以及LiF以及沒有電子注入層之綠光元件，可知藉由低溫蒸鍍CsN3分離出銫(Cs)可與金屬的負電極能階較為匹配，且不會傷害下方有機層。最終我們可得到起始發光電壓約5.5V之元件。其電流效率7.45 cd/A是LiF元件的3.1倍(操作電流為10 mA/cm2)。
在改善電洞傳輸特性方面，由於酸性聚合物材料PEDOT:PSS可能降低元件發光穩定性，因此我們利用可用於溶液製程的MoOx作為電洞注入材料。MoOx是由鉬酸銨四水合物於80 C的環境下製備而成，再將其旋塗於ITO玻璃基板上達成電洞傳輸的目的。與PEDOT:PSS相比，sMoOx有較高的功函數(5.6 eV)，比較好的透光率以及更平整的表面型態。測試結果使用sMoOx作為電洞注入層具有較好的元件穩定性。此外，使用MoOx的元件可以得到10.8 cd/A電流效率和2.2 V起始電壓，而使用PEDOT:PSS的元件僅能獲得9.9 cd/A的電流效率以及2.9 V的起始電壓。此外，由於sMoOx的表面型態較佳，因此其元件的漏電流較小。
接著研究元件的熱穩定性，發現使用巨型漸變厚殼CdSe@ZnS/ZnS量子點的元件可在相當廣泛的溫度範圍內皆可操作。缺陷較少的厚殼量子點可有效減少電子電洞發生無效歐傑複合。更特別的是，即使經歷高溫與高電流所引起的熱應力膨脹仍不會有太多缺陷產生。元件在經歷110 C的熱應力後仍可保留97 % 的電致發光特性，由此可知適當的量子點的結構與品質是影響QLED的運作成效的重要因素。
最終我們使用了巨型量子點製成dot-in-well QLED。我們引入PVK作為載子控制層(CCL)來控制量子點發光層中的載子平衡以提升發光強度。PVK適當的能階搭配良好的載子傳輸特性增加電子電洞對形成激子的數量。加入載子控制層的元件也展現出較好的效率(EQE ~4.3 %)以及較高的最大亮度(Lmax ~41900 cd/m2)，比任何已知元件結構（Type-II量子點發光二極體）都來得傑出。特別的是，加入載子控制層並不會讓起始電壓升高。由於沒有光子在PVK中輻射復合，因此我們得到高純度且穩定的綠光 (536 nm) 。

In this dissertation, we focus on the investigation and characteristics of type-II quantum dot light-emitting diodes (QLEDs) in novel device configuration constructed of both organic electron and hole transport layers with the giant quantum dot emitter.
Firstly, the advantages of giant quantum dots (QDs) on the performance of electroluminescent (EL) devices was demonstrated by comparing gradient core thick-shell CdSe@ZnS/ZnS with gradient core only CdSe@ZnS and thin-shell CdSe/ZnS QDs. Having bigger particle size, gradient thick-shell QDs possess the minimizing of surface defect, the reduced QD charging, the suppressing Auger recombination and the non-radiative energy transfer. Consequently, a much higher performance of EL device was presented with the current efficiency of 2.16 cd/A, and the maximum luminance of 8200 cd/m2.
Then, a QLED was successfully fabricated by utilizing a novel efficient electron injection layer (EIL) of cesium azide (CsN3). All red, green, and blue devices presented over two folds enhancement in performance compared with LiF-devices. Further studying, a green CsN3-device was compared with other counterparts based on CsF, Cs2CO3, LiF, and without EIL. Via directly decomposing to pristine cesium (Cs), the low-temperature evaporated CsN3 provided a better interfacial energy level alignment without damaging the underneath organic layer. Consequently, a lower light turn-on voltage (VLon) in CsN3-devices (~ 5.5 V) was obtained. The current efficiency of 7.45 cd/A was achieved in the CsN3-devices, which was 310% (at 10 mA/cm2) improvement over the LiF-devices.
Due to the acid of polymer PEDOT:PSS which might reduce the stability of photonics devices, a solution-processable MoOx hole injection layer (HIL) was utilized in giant QLEDs. The MoOx HIL was prepared by the decomposition of a solution of ammonium molybdate tetrahydrate at 80 C under ambient conditions, further spin-coated onto an ITO-glass substrate to facilitate hole injection. Compared to a PEDOT:PSS, the sMoOx showed a higher work function (WF) of 5.6 eV, better transparency, and smoother surface morphology. The stability test demonstrates a stable device was established by using sMoOx film. The QLED with optimized MoOx film achieved a higher maximum current efficiency of 10.8 cd/A at a lower turn-on voltage (Von) of 2.2 V versus the one with a PEDOT:PSS HIL, 9.9 cd/A and 2.9 V, respectively. Moreover, a small leakage current in sMoOx-device was found, which was attributed to the better surface morphology of sMoOx.
Next, we investigated the thermal properties of QLEDs, which can work in a wide temperature range by using giant nanoparticle size, and gradient thick-shell CdSe@ZnS/ZnS QDs. Thick-shell QDs with low defective structure can effectively avoid the electron-hole pairs from nonradiative Auger recombination. More specifically, the defects were prevented from thermal-stress-induced expansion at elevated temperatures and high driving current. 97 % of electroluminescent feature can be remained after the device was thermally-stressed at a temperature higher than 110 C, which indicated that rational design and assembly of QDs is an important factor for high-performance QLEDs.
A dot-in-well QLEDs structure was proposed by using giant QDs lastly. The EL enhancement was demonstrated by utilizing a PVK charge control layer (CCL) for controlling the balance of charge carriers inside QD emitters. Proper energy level along with excellent charge transfer characteristics of PVK increased the electron-hole pairs and then more excitons were generated consequently. The CCL-based-devices exhibited much better efficiency (EQE ~ 4.3%) and the higher maximum luminance (Lmax ~ 41900 cd/m2) than type-II QLED devices in previous publications. Especially, no evidence shows any increase of Von due to the insertion of a CCL. The highly pure and stable green light (536 nm) was obtained which was caused by no photon emission from PVK layer in whole operation range.

摘要	I
Abstract	III
Acknowledgements	V
Contents	VI
List of tables	X
List of figures	XI
Nomenclatures	XVI
Chapter 1	 Introduction	1
1	Background of quantum dots	1
1.1	Theory of QDs	1
1.2	Classification of QDs	2
1.3	Core/shell structuring design	3
2	Quantum dot light-emitting diodes	7
2.1	Theory of QDs excitation mechanism	7
2.2	Operating principle of QLEDs	7
2.3	Classification of QLEDs	8
2.4	Important parameters	10
3	Motivation	11
3.1	QLED-next generation of high-quality displays	11
3.2	Giant QDs for QLEDs	11
4	Organization of this dissertation	11
Chapter 2	 Experimental processes and measurement	19
1	Materials in the experiments	19
1.1	Hole injection materials	19
1.2	Hole transport materials	19
1.3	Quantum dots	19
1.4	Electron transport materials	20
1.5	Electron injection materials	21
1.6	Aluminum cathode	21
2	Fabrication process	21
3	Measurement and characterization	21
Chapter 3	 Quantum dot nanostructure for efficient quantum dot light-emitting diodes	25
1	Literature Review	25
2	Motivation	27
3	Device structure and fabrication	27
4	Experimental results and discussion	27
5	Summary	30
Chapter 4	 Cesium Azide - An efficient material for full-color light-emitting diodes with giant quantum dots	35
1	Literature Review	35
2	Motivation	36
3	Device structure and fabrication	36
4	Experimental results and discussion	37
4.1	Cesium azide for full-color giant QLEDs	37
4.2	Comparison with other alkali metal compounds	38
5	Summary	40
Chapter 5	 Solution-processable MoOx for efficient quantum dot light-emitting diodes based on giant quantum dots	49
1	Literature review	49
2	Motivation	50
3	Device structure and fabrication	51
3.1	Prepare precursor MoOx solution	51
3.2	Device configuration and fabrication	51
4	Experimental results and discussion	51
4.1	Giant green quantum dots	51
4.2	Analysis of sMoOx film	52
4.3	Device characterization	53
4.4	Stability test	54
5	Summary	55
Chapter 6	 Enhanced thermal stability of green-emission quantum dot light-emitting diodes via giant quantum dots	64
1	Literature review	64
2	Motivation	65
3	Device structure and fabrication	65
3.1	Materials preparation	65
3.2	Device configuration and fabrication	66
4	Experimental results and discussion	66
4.1	Stability under thermal stress	66
4.2	Stability under continuous driving current stress	68
4.3	Electroluminescent performances	69
5	Summary	71
Chapter 7	 “Dot-in-well” quantum dot light-emitting diodes enabled by a PVK charge control layer	82
1	Literature review	82
2	Motivation	83
3	Device configuration and fabrication	84
4	Experimental results and discussion	84
4.1	Effects of PVK charge control layer	84
4.2	Position of PVK charge control layer	86
5	Summary	87
Chapter 8	 Conclusions and Prospects	96
1	Conclusions	96
2	Prospects	97
References	102
Publication list	112
Vita	114
                                    

[1] J. R. Manders, L. Qian, A. Titov, J. Hyvonen, J. Tokarz-Scott, K. P. Acharya, Y. X. Yang, W. R. Cao, Y. Zheng, J. G. Xue, and P. H. Holloway, "High efficiency and ultra-wide color gamut quantum dot LEDs for next generation displays," Journal of the SID, vol. 23, pp. 523-528, 2015.
[2] L. Qian, Y. Zheng, J. Xue, and P. H. Holloway, "Stable and efficient quantum-dot light-emitting diodes based on solution-processed multilayer structures," Nature Photon., vol. 5, pp. 543-548, 2011.
[3] J. Kwak, W. K. Bae, D. Lee, I. Park, J. Lim, M. Park, H. Cho, H. Woo, Y. Yoon do, K. Char, S. Lee, and C. Lee, "Bright and efficient full-color colloidal quantum dot light-emitting diodes using an inverted device structure," Nano Lett., vol. 12, pp. 2362-2366, 2012.
[4] K. S. Leck, Y. Divayana, D. Zhao, X. Yang, A. P. Abiyasa, E. Mutlugun, Y. Gao, S. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, "Quantum dot light-emitting diode with quantum dots inside the hole transporting layers," ACS Appl. Mater. Interfaces, vol. 5, pp. 6535-6540, 2013.
[5] W. K. Bae, J. Lim, M. Zorn, J. Kwak, Y.-S. Park, D. Lee, S. Lee, K. Char, R. Zentel, and C. Lee, "Reduced efficiency roll-off in light-emitting diodes enabled by quantum dot–conducting polymer nanohybrids," J. Mater. Chem. C, vol. 2, pp. 4974-4979, 2014.
[6] X. Dai, Z. Zhang, Y. Jin, Y. Niu, H. Cao, X. Liang, L. Chen, J. Wang, and X. Peng, "Solution-processed, high-performance light-emitting diodes based on quantum dots," Nature, vol. 515, pp. 96-99, 2014.
[7] Y. L. Kong, I. A. Tamargo, H. Kim, B. N. Johnson, M. K. Gupta, T. W. Koh, H. A. Chin, D. A. Steingart, B. P. Rand, and M. C. McAlpine, "3D printed quantum dot light-emitting diodes," Nano Lett., vol. 14, pp. 7017-7023, 2014.
[8] H. Cho, J. Kwak, J. Lim, M. Park, D. Lee, W. K. Bae, Y. S. Kim, K. Char, S. Lee, and C. Lee, "Soft contact transplanted nanocrystal quantum dots for light-emitting diodes: effect of surface energy on device performance," ACS Appl. Mater. Interfaces, vol. 7, pp. 10828-10833, 2015.
[9] B. H. Kim, M. S. Onses, J. B. Lim, S. Nam, N. Oh, H. Kim, K. J. Yu, J. W. Lee, J. H. Kim, S. K. Kang, C. H. Lee, J. Lee, J. H. Shin, N. H. Kim, C. Leal, M. Shim, and J. A. Rogers, "High-resolution patterns of quantum dots formed by electrohydrodynamic jet printing for light-emitting diodes," Nano Lett., vol. 15, pp. 969-973, 2015.
[10] Y. Yang, Y. Zheng, W. Cao, A. Titov, J. Hyvonen, J. R. Manders, J. Xue, P. H. Holloway, and L. Qian, "High-efficiency light-emitting devices based on quantum dots with tailored nanostructures," Nature Photon., vol. 9, pp. 259–266, 2015.
[11] Z. Ren, J. Wang, Z. Pan, K. Zhao, H. Zhang, Y. Li, Y. Zhao, I. Mora-Sero, J. Bisquert, and X. Zhong, "Amorphous TiO2 buffer layer boosts efficiency of quantum dot sensitized solar cells to over 9%," Chem. Mater., vol. 27, pp. 8398-8405, 2015.
[12] P. K. Santra and P. V. Kamat, "Mn-doped quantum dot sensitized solar cells: a strategy to boost efficiency over 5%," J. Am. Chem.Soc., vol. 134, pp. 2508-2511, 2012.
[13] P. V. Kamat, "Quantum dot solar cells. The next big thing in photovoltaics," J. Phys. Chem. Lett., vol. 4, pp. 908-918, 2013.
[14] D. Kufer, I. Nikitskiy, T. Lasanta, G. Navickaite, F. H. Koppens, and G. Konstantatos, "Hybrid 2D-0D MoS2 -PbS quantum dot photodetectors," Adv Mater., vol. 27, pp. 176-180, 2015.
[15] Z. Jiang, W. Hu, Y. Liu, W. Zhang, C. Mo, G. You, L. Wang, M. R. M. Atalla, Y. Zhang, J. Liu, K. K. Kurhade, and J. Xu, "Suppression of dark current through barrier engineer for solution-processed colloidal quantum-dots infrared photodetectors," Appl. Phys. Lett., vol. 107, pp. 091115-091119, 2015.
[16] F. P. Garcia de Arquer, T. Lasanta, M. Bernechea, and G. Konstantatos, "Tailoring the Electronic Properties of Colloidal Quantum Dots in Metal-Semiconductor Nanocomposites for High Performance Photodetectors," Small, vol. 11, pp. 2636-2641, 2015.
[17] K. J. Chen, H. C. Chen, M. H. Shih, C. H. Wang, M. Y. Kuo, Y. C. Yang, C. C. Lin, and H. C. Kuo, "The influence of the thermal effect on CdSe/ZnS quantum dots in light-emitting diodes," J. Lightw. Technol., vol. 30, pp. 2256-2261, 2012.
[18] C. W. Sher, C. H. Lin, H. Y. Lin, C. C. Lin, C. H. Huang, K. J. Chen, J. R. Li, K. Y. Wang, H. H. Tu, C. C. Fu, and H. C. Kuo, "A high quality liquid-type quantum dot white light-emitting diode," Nanoscale, vol. 8, pp. 1117-1122, 2016.
[19] H. Y. Lin, S. W. Wang, C. C. Lin, K. J. Chen, H. V. Han, Z. Y. Tu, H. H. Tu, T. M. Chen, M. H. Shih, P. T. Lee, H. M. P. Chen, and H. C. Kuo, "Excellent color quality of white-light-emitting diodes by embedding quantum dots in polymers material," IEEE J. Sel. Top. Quantum Electron., vol. 22, pp. 35-41, 2016.
[20] J. Lee, J. Kim, E. Park, S. Jo, and R. Song, "PEG-ylated cationic CdSe/ZnS QDs as an efficient intracellular labeling agent," Phys.Chem. Chem.Phys., vol. 10, pp. 1739-1742, 2008.
[21] T.-H. Kim, K.-S. Cho, E. K. Lee, S. J. Lee, J. Chae, J. W. Kim, D. H. Kim, J.-Y. Kwon, G. Amaratunga, S. Y. Lee, B. L. Choi, Y. Kuk, J. M. Kim, and K. Kim, "Full-colour quantum dot displays fabricated by transfer printing," Nature Photon., vol. 5, pp. 176-182, 2011.
[22] Y. Shirasaki, G. J. Supran, M. G. Bawendi, and V. Bulović, "Emergence of colloidal quantum-dot light-emitting technologies," Nature Photon., vol. 7, pp. 13-23, 2012.
[23] P. Kathirgamanathan, L. M. Bushby, M. Kumaraverl, S. Ravichandran, and S. Surendrakumar, "Electroluminescent organic and quantum dot LEDs: The state of the art," J. Display Technol., vol. 11, pp. 480-493, 2015.
[24] B. N. Pal, Y. Ghosh, S. Brovelli, R. Laocharoensuk, V. I. Klimov, J. A. Hollingsworth, and H. Htoon, "'Giant' CdSe/CdS core/shell nanocrystal quantum dots as efficient electroluminescent materials: strong influence of shell thickness on light-emitting diode performance," Nano Lett., vol. 12, pp. 331-336, 2012.
[25] C.-J. Chen, R.-K. Chiang, C.-Y. Huang, J.-Y. Lien, and S.-L. Wang, "Thiol treatment to enhance photoluminescence and electroluminescence of CdSe/CdS core–shell quantum dots prepared by thermal cycling of single source precursors," RSC Adv., vol. 5, pp. 9819-9827, 2015.
[26] S. Kim, B. Fisher, H. Y. Eisler, and M. G. Bawendi, "Type-II quantum dots: CdTe/CdSe(core/shell) and CdSe/ZnTe(core/shell) heterostructures," J. Am. Chem. Soc., vol. 125, pp. 11466–11467, 2003.
[27] V. Wood and V. Bulovic, "Colloidal quantum dot light-emitting devices," Nano Rev., vol. 1, pp. 1–7, 2010.
[28] D. Bozyigit and V. Wood, "Challenges and solutions for high-efficiency quantum dot-based LEDs," MRS Bulletin, vol. 38, pp. 731-736, 2013.
[29] X. B. Wang, W. W. Li, and K. Sun, "Stable efficient CdSe/CdS/ZnS core/multi-shell nanophosphors fabricated through a phosphine-free route for white light-emitting-diodes with high color rendering properties," J. Mater. Chem. C, vol. 21, pp. 8558-8565, 2011.
[30] S. Jun and E. Jang, "Bright and stable alloy core/multishell quantum dots," Angew. Chem. Int. Ed., vol. 52, pp. 679-682, 2013.
[31] D. V. Talapin, I. Mekis, S. Gotzinger, A. Kornowski, O. Benson, and H. Weller, "CdSe/CdS/ZnS and CdSe/ZnSe/ZnS core-shell-shell nanocrystals," J. Phys. Chem. B, vol. 108, pp. 18826-18831, 2004.
[32] J. Lim, B. G. Jeong, M. Park, J. K. Kim, J. M. Pietryga, Y. S. Park, V. I. Klimov, C. Lee, D. C. Lee, and W. K. Bae, "Influence of shell thickness on the performance of light-emitting devices based on CdSe/Zn1-X CdXS core/shell heterostructured quantum dots," Adv. Mater., vol. 26, pp. 8034-8040, 2014.
[33] H. Shen, Q. Lin, H. Wang, L. Qian, Y. Yang, A. Titov, J. Hyvonen, Y. Zheng, and L. S. Li, "Efficient and bright colloidal quantum dot light-emitting diodes via controlling the shell thickness of quantum dots," ACS Appl. Mater. Interfaces, vol. 5, pp. 12011-12016, 2013.
[34] W. K. Bae, L. A. Padilha, Y.-S. Park, H. McDaniel, I. Robel, J. M. Pietryga, and V. I. Klimov, "Controlled alloying of the core–shell interface in CdSe/CdS quantum dots for suppression of Auger recombination," ACS Nano, vol. 7, p. 9, 2013
[35] J. S. Steckel, P. Snee, S. Coe-Sullivan, J. R. Zimmer, J. E. Halpert, P. Anikeeva, L. A. Kim, V. Bulovic, and M. G. Bawendi, "Color-saturated green-emitting QD-LEDs," Angew. Chem. Int. Ed., vol. 45, pp. 5796-5799, 2006.
[36] W. K. Bae, J. Kwak, J. W. Park, K. Char, C. Lee, and S. Lee, "Highly efficient green-light-emitting diodes based on CdSe@ZnS quantum dots with a chemical-composition gradient," Adv. Mater., vol. 21, pp. 1690-1694, 2009.
[37] V. L. Colvin, M. C. Schlamp, and A. P. Alivisatos, "Light-emitting-diodes made from cadmium selenide nanocrystals and a semiconducting polymer," Nature, vol. 370, pp. 354-357, 1994.
[38] B. O. Dabbousi, M. G. Bawendi, O. Onitsuka, and M. F. Rubner, "Electroluminescence from Cdse Quantum-Dot Polymer Composites," Appl. Phys. Lett., vol. 66, pp. 1316-1318, 1995.
[39] Z. N. Tan, F. Zhang, T. Zhu, J. Xu, A. Y. Wang, D. Dixon, L. S. Li, Q. Zhang, S. E. Mohney, and J. Ruzyllo, "Bright and color-saturated emission from blue light-emitting diodes based on solution-processed colloidal nanocrystal quantum dots," Nano Lett., vol. 7, pp. 3803-3807, 2007.
[40] C. Y. Huang, T. S. Huang, Y. C. Chen, and C. T. Wan, "Hybrid quantum dot light-emitting diodes: Design, fabrication, and characterization," PhotonicsGlobal@ Singapore, 2008. IPGC 2008,
[41] X. Yang, P. L. Hernandez-Martinez, C. Dang, E. Mutlugun, K. Zhang, H. V. Demir, and X. W. Sun, "Electroluminescence efficiency enhancement in quantum dot light-emitting diodes by embedding a silver nanoisland layer," Adv. Optical Mater., vol. 3, pp. 1439-1445, 2015.
[42] E. Mutlugun, B. Guzelturk, A. P. Abiyasa, Y. Gao, X. W. Sun, and H. V. Demir, "Colloidal quantum dot light-emitting diodes employing phosphorescent small organic molecules as efficient exciton harvesters," J. Phys. Chem. Lett., vol. 5, pp. 2802-2807, 2014.
[43] X. L. Zhang, H. T. Dai, J. L. Zhao, C. Li, S. G. Wang, and X. W. Sun, "Effects of the thickness of NiO hole transport layer on the performance of all-inorganic quantum dot light emitting diode," Thin Solid Films, vol. 567, pp. 72-76, 2014.
[44] B. S. Mashford, T.-L. Nguyen, G. J. Wilson, and P. Mulvaney, "All-inorganic quantum-dot light-emitting devices formed via low-cost, wet-chemical processing," J. Mater. Chem., vol. 20, pp. 167-172, 2010.
[45] V. Wood, M. J. Panzer, J. E. Halpert, J. M. Caruge, M. G. Bawendi, and V. Bulovic, "Selection of metal oxide charge transport layers for colloidal quantum dot LEDs," ACS Nano, vol. 3, pp. 3581-3586, 2009.
[46] K. H. Lee, J. H. Lee, H. D. Kang, B. Park, Y. Kwon, H. Ko, C. Lee, J. Lee, and H. Yang, "Over 40 cd/A efficient green quantum dot electroluminescent device comprising uniquely large-sized quantum dots," ACS Nano, vol. 8, pp. 4893-4901, 2014.
[47] J. Y. Pan, J. Chen, Q. Q. Huang, Q. Khan, X. Liu, Z. Tao, Z. C. Zhang, W. Lei, and A. Nathan, "Size Tunable ZnO Nanoparticles To Enhance Electron Injection in Solution Processed QLEDs," Acs Photonics, vol. 3, pp. 215-222, 2016.
[48] J.-H. Kim, C.-Y. Han, K.-H. Lee, K.-S. An, W. Song, J. Kim, M. S. Oh, Y. R. Do, and H. Yang, "Performance improvement of quantum dot-light-emitting diodes enabled by an alloyed ZnMgO nanoparticle electron transport layer," Chem. Mater., vol. 27, pp. 197-204, 2015.
[49] http://www.tf.unikiel.de/matwis/amat/semitech_en/kap_2/backbone/r2_3_1.html,
[50] L. M. Lacroix, F. Delpech, C. Nayral, S. Lachaize, and B. Chaudret, "New generation of magnetic and luminescent nanoparticles for in vivo real-time imaging," Interface Focus, vol. 3, pp. 20120103-20120122, 2013.
[51] A. M. Smith and S. Nie, "Semiconductor nanocrystals: Structure, properties, and band gap engineering," Accounts Chem. Res., vol. 43, pp. 190–200, 2010.
[52] http://www.nextbigfuture.com./2011/07/creating-fuels-directly-from-solar.html?m=1,
[53] L. Xiao, Z. Chen, B. Qu, J. Luo, S. Kong, Q. Gong, and J. Kido, "Recent progresses on materials for electrophosphorescent organic light-emitting devices," Adv Mater., vol. 23, pp. 926-952, 2011.
[54] D. Bozyigit, O. Yarema, and V. Wood, "Origins of low quantum efficiencies in quantum dot LEDs," Adv. Funct. Mater., vol. 23, pp. 3024-3029, 2013.
[55] V. L. Colvin, M. C. Schlamp, and A. P. Alivisatos, "Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer," Nature Photon., vol. 370, pp. 354 - 357, 1994.
[56] S. Coe, W. K. Woo, M. Bawendi, and V. Bulovic, "Electroluminescence from single monolayers of nanocrystals in molecular organic devices," Nature, vol. 420, pp. 800-803, 2002.
[57] S. Kim, S. H. Im, and S. W. Kim, "Performance of light-emitting-diode based on quantum dots," Nanoscale, vol. 5, pp. 5205-5214, 2013.
[58] M. D. Ho, D. Kim, N. Kim, S. M. Cho, and H. Chae, "Polymer and small molecule mixture for organic hole transport layers in quantum dot light-emitting diodes," ACS Appl. Mater. Interfaces, vol. 5, pp. 12369-12374, 2013.
[59] B. H. Kang, S. W. Lee, S. W. Lim, T. Y. You, S. H. Yeom, K. J. Kim, D. H. Kwon, and S. W. Kang, "Enhanced charge transfer of QDs/polymer hybrid LED by interface controlling," IEEE Photon. Technol. Lett., vol. 34, pp. 656-658, 2013.
[60] W. Y. Ji, P. T. Jing, L. G. Zhang, D. Li, Q. H. Zeng, S. N. Qu, and J. L. Zhao, "The work mechanism and sub-bandgap-voltage electroluminescence in inverted quantum dot light-emitting diodes," Sci. Rep., vol. 4, pp. 1-6, 2014.
[61] H.-M. Kim, A. R. b. Mohd Yusoff, T.-W. Kim, Y.-G. Seol, H.-P. Kim, and J. Jang, "Semi-transparent quantum-dot light emitting diodes with an inverted structure," J. Mater. Chem. C, vol. 2, p. 2259, 2014.
[62] J. Lee, H. Lee, P. Jeon, K. Jeong, T. Gun Kim, J. Won Kim, and Y. Yi, "Direct evidence of n-type doping in organic light-emitting devices: N free Cs doping from CsN3," Appl. Phys. Lett., vol. 100, pp. 203301-203304, 2012.
[63] J. Huang, Z. Xu, and Y. Yang, "Low-Work-Function Surface Formed by Solution-Processed and Thermally Deposited Nanoscale Layers of Cesium Carbonate," Adv. Funct. Mater., vol. 17, pp. 1966-1973, 2007.
[64] K. S. Yook, S. O. Jeon, S.-Y. Min, J. Y. Lee, H.-J. Yang, T. Noh, S.-K. Kang, and T.-W. Lee, "Highly efficient p-i-n and tandem organic light-emitting devices using an air-stable and low-temperature-evaporable metal azide as an n-dopant," Adv. Funct. Mater., vol. 20, pp. 1797-1802, 2010.
[65] P. Piromreun, H. Oh, Y. Shen, G. G. Malliaras, J. C. Scott, and P. J. Brock, "Role of CsF on electron injection into a conjugated polymer," Appl. Phys. Lett., vol. 77, pp. 2403-2405, 2000.
[66] H.-M. Kim, A. R. bin Mohd Yusoff, J.-H. Youn, and J. Jang, "Inverted quantum-dot light emitting diodes with cesium carbonate doped aluminium-zinc-oxide as the cathode buffer layer for high brightness," J. Mater. Chem. C, vol. 1, p. 3924, 2013.
[67] C. Y. Huang and J. H. Lai, "Efficient polymer light-emitting diodes with ZnO nanoparticles and interpretation of observed sub-bandgap turn-on phenomenon," Org. Electron., vol. 32, pp. 244-249, 2016.
[68] A. Castan, H. M. Kim, and J. Jang, "All-solution-processed inverted quantum-dot light-emitting diodes," ACS Appl. Mater. Interfaces, vol. 6, pp. 2508-2515, 2014.
[69] S. Murase and Y. Yang, "Solution processed MoO3 interfacial layer for organic photovoltaics prepared by a facile synthesis method," Adv Mater., vol. 24, pp. 2459-2462, 2012.
[70] X. Yang, E. Mutlugun, Y. Zhao, Y. Gao, K. S. Leck, Y. Ma, L. Ke, S. T. Tan, H. V. Demir, and X. W. Sun, "Solution processed tungsten oxide interfacial layer for efficient hole-injection in quantum dot light-emitting diodes," Small, vol. 10, pp. 247-252, 2014.
[71] V. Wood, M. J. Panzer, J. M. Caruge, J. E. Halpert, M. G. Bawendi, and V. Bulovic, "Air-stable operation of transparent, colloidal quantum dot based LEDs with a unipolar device architecture," Nano Lett., vol. 10, pp. 24-29, 2010.
[72] J. M. Caruge, J. E. Halpert, V. Wood, V. Bulović, and M. G. Bawendi, "Colloidal quantum-dot light-emitting diodes with metal-oxide charge transport layers," Nat. Photon., vol. 2, pp. 247-250, 2008.
[73] H. T. Nguyen, N. D. Nguyen, and S. Lee, "Application of solution-processed metal oxide layers as charge transport layers for CdSe/ZnS quantum-dot LEDs," Nanotechnology, vol. 24, pp. 115201-115205, 2013.
[74] X. Yang, Y. Ma, E. Mutlugun, Y. Zhao, K. S. Leck, S. T. Tan, H. V. Demir, Q. Zhang, H. Du, and X. W. Sun, "Stable, efficient, and all-solution-processed quantum dot light-emitting diodes with double-sided metal oxide nanoparticle charge transport layers," ACS Appl. Mater. Interfaces, vol. 6, pp. 495-499, 2014.
[75] M.-F. Xu, L.-S. Cui, X.-Z. Zhu, C.-H. Gao, X.-B. Shi, Z.-M. Jin, Z.-K. Wang, and L.-S. Liao, "Aqueous solution-processed MoO3 as an effective interfacial layer in polymer/fullerene based organic solar cells," Org. Electron., vol. 14, pp. 657-664, 2013.
[76] J. Liang, F.-S. Zu, L. Ding, M.-F. Xu, X.-B. Shi, Z.-K. Wang, and L.-S. Liao, "Aqueous solution-processed MoO3 thick films as hole injection and short-circuit barrier layer in large-area organic light-emitting devices," Appl. Phys. Express, vol. 7, p. 111601, 2014.
[77] Q. Fu, J. Chen, C. Shi, and D. Ma, "Room-temperature sol-gel derived molybdenum oxide thin films for efficient and stable solution-processed organic light-emitting diodes," ACS Appl. Mater. Interfaces, vol. 5, pp. 6024-6029, 2013.
[78] H. T. Vu, C. Y. Huang, C. J. Chen, R. K. Chiang, H. C. Yu, Y. C. Chen, and Y. K. Su, "Cesium azide-An efficient material for green light-emitting diodes with giant quantum dots," IEEE Photon. Technol. Lett., vol. 27, pp. 2123-2126, 2015.
[79] W. K. Bae, L. A. Padilha, Y. S. Park, H. McDaniel, I. Robel, J. M. Pietryga, and V. I. Klimov, "Controlled alloying of the core-shell interface in CdSe/CdS quantum dots for suppression of Auger recombination," ACS Nano, vol. 7, pp. 3411-3419, 2013.
[80] W. K. Bae, Y. S. Park, J. Lim, D. Lee, L. A. Padilha, H. McDaniel, I. Robel, C. Lee, J. M. Pietryga, and V. I. Klimov, "Controlling the influence of Auger recombination on the performance of quantum-dot light-emitting diodes," Nat. Commun., vol. 4, p. 2661, 2013.
[81] W. K. Bae, J. Kwak, J. Lim, D. Lee, M. K. Nam, K. Char, C. Lee, and S. Lee, "Multicolored light-emitting diodes based on all-quantum-dot multilayer films using layer-by-layer assembly method," Nano Lett., vol. 10, pp. 2368-2373, 2010.
[82] H. Aziz, Z. D. Popovic, and N.-X. Hu, "Organic light emitting devices with enhanced operational stability at elevated temperatures," Appl. Phys. Lett., vol. 81, pp. 370-372, 2002.
[83] I. R. de Moraes, S. Scholz, M. Hermenau, M. L. Tietze, T. Schwab, S. Hofmann, M. C. Gather, and K. Leo, "Impact of temperature on the efficiency of organic light emitting diodes," Org. Electron., vol. 26, pp. 158-163, 2015.
[84] Z.-Y. Liu, S.-R. Tseng, Y.-C. Chao, C.-Y. Chen, H.-F. Meng, S.-F. Horng, Y.-H. Wu, and S.-H. Chen, "Solution-processed small molecular electron transport layer for multilayer polymer light-emitting diodes," Synth. Met., vol. 161, pp. 426-430, 2011.
[85] S.-W. Guo, L.-A. Hong, H.-T. Vu, F.-S. Juang, Y.-S. Tsai, and C.-W. Chu, "Fabrication of multilayer small molecule organic light emitting diodes using solution-based processing and stamping," IMID Korea, 2012.
[86] Y. H. Niu, A. M. Munro, Y. J. Cheng, Y. Q. Tian, M. S. Liu, J. L. Zhao, J. A. Bardecker, I. Jen-La Plante, D. S. Ginger, and A. K. Y. Jen, "Improved performance from multilayer quantum dot light-emitting diodes via thermal annealing of the quantum dot layer," Adv. Mater., vol. 19, pp. 3371-3376, 2007.
[87] S. Bhaumik and A. J. Pal, "Light-emitting diodes based on solution-processed nontoxic quantum dots: oxides as carrier-transport layers and introducing molybdenum oxide nanoparticles as a hole-inject layer," ACS Appl. Mater. Interfaces, vol. 6, pp. 11348-11356, 2014.
[88] J. Tao, H. Z. Wang, Q. L. Lin, H. B. Shen, and L. S. Li, "Quantum-dot-based light-emitting diodes with improved brightness and stability by using sulfuric acid-treated PEDOT:PSS as efficient hole injection layer," IEEE Trans. Nanotechnol., vol. 14, pp. 57-61, 2015.
[89] J. Y. Kim, A. R. B. Yusoff, and J. Jang, "Quantum-dot light-emitting diode featuring polymeric metal oxide anode buffer layer," IEEE J. Sel. Top. Quantum Electron., vol. 21, pp. 1900206-1900211, 2015.
[90] A. V. Klekachev, S. N. Kuznetsov, I. Asselberghs, M. Cantoro, J. Hun Mun, B. Jin Cho, A. L. Stesmans, M. M. Heyns, and S. De Gendt, "Graphene as anode electrode for colloidal quantum dots based light emitting diodes," Appl. Phys. Lett., vol. 103, pp. 043124-043127, 2013.
[91] H.-T. Vu, Y.-K. Su, R.-K. Chiang, C.-Y. Huang, C.-J. Chen, and H.-C. Yu, "Solution-processable MoOx for efficient light-emitting diodes based on giant quantum dots," IEEE Photon. Technol. Lett., pp. 2156-2159, 2016.
[92] T. Ding, X. Y. Yang, L. Ke, Y. J. Liu, W. Y. Tan, N. Wang, X. H. Zhu, and X. W. Sun, "Improved quantum dot light-emitting diodes with a cathode interfacial layer," Org. Electron., vol. 32, pp. 89-93, 2016.
[93] H.-T. Vu, R.-K. Chiang, C.-Y. Huang, C.-J. Chen, H.-C. Yu, J.-Y. Lien, and Y.-K. Su, "Enhanced thermal stability of green-emission quantum-dot light-emitting diodes via composition-gradient thick-shell quantum dots," Appl. Phys. Express, vol. 9, pp. 082101-082104, 2016.

校內：2019-12-01公開
校外：2020-12-01公開

簡易檢索 / 詳目顯示

相關論文