Ge/Si波导集成型APD器件的仿真分析

设计了一种Ge/Si波导集成型雪崩光电二极管(APD).器件采用将Si波导层置于Ge吸收层之下的结构,光经波导层进入吸收层只需一次耦合,降低了光的损耗,提高了光的吸收率和光电流.采用silvaco软件对器件的结构和性能进行仿真,结果表明:器件的雪崩击穿电压为-28 V,最大内量子效率达到89％,在1.15～1.60 μm范围内具有较高响应度,峰值波长位于1.31μm,单位响应度最高达0.74 A/W,3 dB带宽为10 GHz.     

新型有机电致蓝色磷光器件的研究

研究了基于FIrpic的超薄非掺杂有机电致蓝色磷光器件的光电特性.改变超薄非掺杂FIrpic发光层以及其隔离层的厚度,可以调控FIrpic分子的聚集及激子相互作用强度对器件性能的影响.研究结果表明,具有TCTA 5 nm/FIrpic 1 nm/TCTA 5 nm/FIrpic 1 nm/TPBI 5 nm/FIrpic 1 nm多发光层结构的器件性能较优,最大发光效率为9.9 cd/A,超薄非掺杂发光层结构避免了掺杂方法中共沉积磷光材料浓度的精确控制,有利于简化器件制备工艺.     

Ge/Si SACM-APD器件分析

Ge/Si吸收区-电荷区-倍增区分离(SACM)结构的APD作为一种新型光电探测器已成为硅基APD器件研究的重点.对SACM Ge/Si型APD器件的基本结构及其主要特性参数,包括量子效率、响应度、暗电流等进行了理论分析及仿真验证.实验结果表明:在给定的器件参数条件下,所设计的APD器件的雪崩击穿电压为25.7 V,最大内部量子效率为91%,单位增益下响应度峰值为0.55 A/W,在750~1 500 nm范围内具有较高响应度,其峰值波长为1 050 nm;在高偏压以及高光照强度情况下,倍增区发生空间电荷效应从而导致增益降低.     

基于磷光材料的有机电致白光器件的研究进展

有机电致白光器件是近年来国际上的一个研究热点,它不仅可以作为液晶显示的背光源,也是未来照明技术的有效光源。有机磷光电致发光可以同时利用单重态和三重态的激子,理论上可使器件的内量子效率达到100%,而在近几年倍受关注。文章介绍了磷光材料的有机电致白光器件的研究进展,按多发射层、多重掺杂单发射层、单重掺杂单发射层以及基于激发二聚体和激基复合物发射4种结构进行了分析和阐述。     

InGaAs/Si雪崩光电二极管

采用Si/InP低温晶片键合技术,设计并制作了InGaAs/Si雪崩光电二极管.器件利用InGaAs做吸收层,Si做增益层,光敏面大小50μm×70μm;测试结果表明器件有正常的光响应特性,击穿电压为41 V,暗电流为99 nA,此时光电流比暗电流高3个数量级.     

长波长高速雪崩光电二极管的理论研究

本文以现有的理论研究和实验研究的结果为依据,提出了长波长高速及超高速雪崩光电二极管(APD)的两设计原则:一是在雪崩管内建立合理的电场强度分布;二是尽可能减少电寄生。这是得到高速或超高速响应、高量子效率以及低噪声性能的根本途径。     

CBP超薄层对有机电致磷光器件效率的影响

在空穴传输层(HTL)和发光层(EML)间插入4,4-N,N′-二咔唑基联苯(CBP)超薄层,制备了结构为ITO/NPB/CBP(xnm)/CBP:Ir(ppy)3/BCP/Alq3/LiF/Al有机电致磷光器件。与未插入CBP超薄层的器件相比,CBP超薄层的引入可以有效阻挡Ir(ppy)3的三线态能量通过Dexter能量转移到HTL的NPB中,减少无辐射能量损失,提高了器件发光效率。调整CBP薄层的厚度,当x为3nm时,器件的效率提高幅度最大,从x为0nm时的9.0cd/A提高到16.9cd/A。     

基于0.35μm CMOS工艺的APD器件仿真分析

提出了一种基于0.35μm CMOS工艺的、具有p+/n阱二极管结构的雪崩光电二极管(APD),器件引入了p阱保护环结构.采用silvaco软件对CMOS-APD器件的关键性能指标进行了仿真分析.仿真结果表明:p阱保护环的应用,明显降低了击穿电压下pn结边缘电场强度,避免了器件的提前击穿.CMOS APD器件的击穿电压为9.2V,工作电压下响应率为0.65 A/W,最大内部量子效率达到90％以上,响应速度能够达到6.3 GHz,在400～900 nm波长范围内,能够得到很大的响应度.     

加CdS薄层的有机电致磷光白光器件性能的优化

采用CBP和MCP做主体,分别掺杂磷光铱配合物Ir(piq)2(acac)和FIrpic作为红光发光层和蓝光发光层,研究了红光发光层和蓝光发光层的位置对器件性能的影响,得出结构为ITO/2T/NPB/MCP∶Firpic/CBP/CBP∶Ir(piq)2(acac)/Bphen/CdS/LiF/Al的器件性能较好。当CdS的厚度为0.1nm,电流密度为161mA/cm2时,器件的最大效率比不加CdS的器件的最大效率提高了1.42倍。亮度也有较大提高。在电流密度为225mA/cm2(电压为17.5V)时,最大亮度为20 890cd/m2,比不加CdS的器件的最大亮度16 610cd/m2高出4 280cd/m2。     

高效率白色有机电致发光器件

通过引入磷光材料Ir(pPy3)作为敏化剂,制作了高效率的白色有机电致发光器件.Ir(pPy)3和荧光染料DCJTB共掺入CBP母体中.此共掺层的厚度以及浓度都影响到整个器件的效率和颜色.Alq和BCP分别用作电子传输层和激子阻挡层,NPB用作蓝光发光层和空穴传输层.器件的最大效率和亮度分别可以达到9 cd/A和12 020 cd/m2.通过调节掺杂层的厚度以及Ir(ppy)3和DCJTB的浓度,可以得到相当纯正的白光,其色坐标为(0.33,0.32),在10～19 V的范围内几乎不随驱动电压的变化而变化.     

Improved Efficiency in Blue Phosphorescent Organic Light‐Emitting Devices Using Host Materials of Lower Triplet Energy than the Phosphorescent Blue Emitter

Data from a series of phosphorescent blue organic light‐emitting devices with emissive layers consisting of either 4,4′‐bis(N‐carbazolyl)‐2,2′‐biphenyl (CBP):6% bis[(4,6‐difluorophenyl)pyridinato‐N,C²](picolinato)iridium(III) (FIrpic) or bis(9‐carbazolyl)benzene (mCP):6% FIrpic show that the triplet energy of the hole and electron transport layers can have a larger influence on the external quantum efficiency of an operating device than the triplet energy of the host material. A maximum external quantum efficiency of 14% was obtained for CBP:6% FIrpic devices which is nearly double all other published CBP:6% FIrpic results. A new host material, 4‐(diphenylphosphoryl)‐N,N‐di‐p‐tolylaniline (DHM‐A2), which has a triplet energy lower than that of FIrpic is also reported. Devices fabricated using DHM‐A2 show improved performance (lower drive voltage and higher external quantum efficiency) over devices using 4‐(diphenylphosphoryl)‐N,N‐diphenylaniline (HM‐A1), a high performance ambipolar DHM‐A2 analogue with a triplet energy greater than FIrpic. Nearly 18% external quantum efficiency was obtained for the DHM‐A2:5% FIrpic devices. The results suggest modified design rules for the development of high performance host materials: more focus can be placed on molecular structures that provide good charge transport (ambipolarity for charge balance) and good molecular stability (for long lifetimes) rather than first focusing on the triplet energy of the host material.     

Interlayer Engineering with Different Host Material Properties in Blue Phosphorescent Organic Light‐Emitting Diodes

We investigated the light‐emitting performances of blue phosphorescent organic light‐emitting diodes, known as PHOLEDs, by incorporating an N,N’‐dicarbazolyl‐3,5‐benzen interlayer between the hole transporting layer and emitting layer (EML). We found that the effects of the introduced interlayer for triplet exciton confinement and hole/electron balance in the EML were exceptionally dependent on the host materials: 9‐(4‐tert‐butylphenyl)‐3.6‐bis(triphenylsilyl)‐9H‐carbazole, 9‐(4‐tert‐butylphenyl)‐3.6‐ditrityl‐9H‐carbazole, and 4,4’‐bis‐triphenylsilanyl‐biphenyl. When an appropriate interlayer and host material were combined, the peak external quantum efficiency was greatly enhanced by over 21 times from 0.79% to 17.1%. Studies on the recombination zone using a series of host materials were also conducted.     

Dependence of Light‐Emitting Characteristics of Blue Phosphorescent Organic Light‐Emitting Diodes on Electron Injection and Transport Materials

We investigate the light‐emitting performances of blue phosphorescent organic light‐emitting diodes (PHOLEDs) with three different electron injection and transport materials, that is, bathocuproine(2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline) (Bphen), 1,3,5‐tri(m‐pyrid‐3‐yl‐phenyl)benzene (Tm3PyPB), and 2,6‐bis(3‐(carbazol‐9‐yl)phenyl)pyridine (26DCzPPy), which are partially doped with cesium metal. We find that the device characteristics are very dependent on the nature of the introduced electron injection layer (EIL) and electron transporting layer (ETL). When the appropriate EIL and ETL are combined, the peak external quantum efficiency and peak power efficiency improve up to 20.7% and 45.6 lm/W, respectively. Moreover, this blue PHOLED even maintains high external quantum efficiency of 19.6% and 16.9% at a luminance of 1,000 cd/m² and 10,000 cd/m², respectively.     

有机薄膜电致发光器件的研究

系统介绍了有机电致发光器件(OLED)的结构和发光机理,从有机半导体的能带结构和OLED的能带结构,分析了OLED发光过程,指出了如何提高器件的发光效率.最后概述了器件的最新进展和应用前景,并展望了未来OLED发展的方向.     

基于DSA-ph的高效率超薄层蓝色有机电致发光器件

讨论了基于蓝色荧光染料DSA-ph作为发光层的蓝色有机电致发光器件,器件结构为：ITO/2T-NATA/NPBX/DSA-ph（xnm）/TAZ/Bphen/LiF/Al。通过改变DSA-ph的超薄层厚度,相应器件的性能指标也有所不同。研究表明,在超薄层厚度为0.5nm,驱动电压为4V时,器件的最大发光效率为6.57cd/A;在超薄层厚度为0.3nm时,驱动电压为10V时,器件的最大亮度为5 122cd/m^2。器件的色坐标在（0.17,0.36）附近,属于蓝光发射。     

基于ADN的非掺杂高效蓝色OLED器件

采用真空蒸镀的方法,制备了以ADN为发光层的高效率非掺杂蓝色有机电致发光器件.器件的结构为ITO/2T-NATA(15 nm)/NPBx(15 nm)/ADN(25+d nm)/BCP(8 nm)/ Alq_3(30 nm)/LiF(0.5 nm)/Al.通过调整ADN层的厚度,研究了器件的发光性能.测试结果表明,器件在6 V电压时电流效率达到最大,为2.77 cd/A;在16 V时亮度达到最大,为7 227 cd/m~2.当ADN的厚度为30 nm、器件的电压从5 V变化到16 V时,色坐标在(0.21,0.32)至(0.19,0.29)之间,均在蓝光区域.

Abstract：

Using ADN as the emitting layer, high efficient undoped blue organic light-emitting diodes(OLEDs) with a typical structure of (ITO)/ 2T-NATA(15 nm)/ NPBx(15 nm)/ ADN(25+d nm)/BCP(8 nm)/Alq_3 (30 nm)/LiF(0.5 nm)/Al were fabricated via thermal vacuum deposition method. This device has a maximum luminous efficiency of 2.77 cd/A at 6 V and maximum luminance of 7 227 cd/m~2 at 16 V. The CIE coordinates of the device are within the blue region when the thickness of ADN is 30 nm and the voltage changes among the range of 6～16 V.     

利用新型的空穴注入层材料提高有机发光器件性能

研究使用新材料2-TNATA作空穴注入层制备OLED,发现空穴注入层厚度的最佳参数为35 nm,器件的发光光谱随空穴注入层厚度并不发生显著变化,微腔作用对发光光谱的影响基本可以忽略.并将2-TNATA作为空穴注入层的器件同CuPc制作的器件进行了对比,发现使用2-TNATA能获得更佳的器件性能.     

基于薄层铱配合物的有机电致发光器件研究

采用蓝色磷光染料bis[(4,6-diflourophenyl)-pyridinato-N,C2’)](picolinato) Iridium (III)(FI rpic)和黄色磷光染料bis[2-(4-tertbutylphenyl) benzothiazolato-N,C2,]iridium(acetylacetonate)[(t-bt)2 Ir(acac)]为超薄层,制备了结构为ITO/NPB/mCP/(t-bt)2Ir (acac)/mCP/Flrpic/mCP/TPBi/Mg:Ag的白色有机电致发光器件.通过调节磷光染料双超薄层Flrpic和(t-bt)2Ir(acac)的厚度,优化了白光器件的性能.结果表明,白光器件的最高电流效率为13.08 cd/A,最高功率效率为7.21 lm/W,发光光谱稳定,在9V时得到色坐标为(0.33,o.33)的标准白光,并且在较宽的电压范围内仅有(±0.08,±0.08)变化.这是由于超薄层FIrpic和(t-bt)2Ir(acac)形成的陷阱效应直接俘获电子和空穴,从而将载流子复合区域限制在一定范围内,不仅有利于增加激子的辐射发光效率,且提高了光谱的稳定性.