有机层／阴极界面修饰对体异质结聚合物太阳能电池性能的影响

通过制备四种不同结构的器件,详细分析研究了活性层／阴极界面修饰对P3HT:PCBM聚合物体异质结太阳能电池性能的影响。当在P3HT:PCBM薄膜上旋涂一层PCBM,并蒸镀0.5 nm LiF时所制备的器件的填充因子和光电转换效率都得到较大的提高。对器件的光电性能和薄膜的形貌进行深入分析,阐明界面修饰的作用机理。     

金属键合技术及其在光电器件中的应用

系统阐述了金属键合的发展概况、基本工艺和方法、表征技术及其在光电器件中的应用.金属键合制备光电器件的一般工艺流程分为三步:蒸镀金属薄膜、键合、腐蚀去除衬底,列举了常用的金属键合方法及其工艺条件;并着重论述了该技术在光电器件特别是垂直腔面发射激光器(VCSEL)器件结构制作中的应用.金属键合可以实现衬底倒扣和改善器件热学性能,而对器件原有的光学性质影响不大.     

直流磁控溅射法制备本征ZnO薄膜及光伏应用研究

采用直流磁控溅射法制备了ZnO薄膜,研究了沉积过程中变换氧分压对薄膜光电性能的影响.采用XRD、紫外可见光分光光度计及AFM等方法对薄膜的结构和光电性质进行了表征.结果表明,ZnO薄膜在可见光范围内的透过率可达88％,并且随着氧分压的增大,薄膜的透过率也增大;制备出的ZnO薄膜表面粗糙度为0.41 nm.在glass/ITO/CdS/CdTe结构的太阳电池中,将本征ZnO薄膜作为高阻层加入到ITO与CdS之间,电池的开路电压和填充因子有明显的提高,加入高阻层之后,电池的转换效率最高可达13.6％.     

染敏料化太阳能电池中TiO_2薄膜的研究进展

纳米TiO2薄膜的组成及结构在很大程度上影响着染料敏化太阳能电池的光电转化效率。从微观结构、复合结构、掺杂、表面处理四方面综述了染料敏化太阳能电池中纳米TiO2薄膜的最新研究成果,探讨了如何通过提高电池中纳米TiO2薄膜对光的吸收、提高电荷的传输效率、降低电荷的复合来优化电池性能。对TiO2薄膜的表面处理,是今后发展的一个主要方向。     

制备高质量ZnO光电薄膜的关键技术

提高ZnO薄膜的质量,使之适应制备光电器件的要求,是目前ZnO薄膜研究的一个主要问题。在对近年来人们在ZnO薄膜的制备上所作的工作进行调研的基础上,总结出对提高薄膜的质量有普遍参考价值的三种关键技术:“缓冲层”,“氢钝化”和“表面化学处理”。对三种关键技术的主要内容,及其在提高薄膜结晶质量与光电性能方面的效果和物理机制,作了较详细的介绍。并对这些技术提出了自己的一些见解。     

薄膜太阳能电池的研究进展

薄膜太阳能电池是缓解能源危机的新型光伏器件。评述了薄膜太阳能电池的优缺点,主要介绍了薄膜硅太阳能电池、多元化合物薄膜太阳能电池和有机薄膜太阳能电池的研究现状,总结了它们各自在价格成本、光电转换效率及对环境影响等方面的特点,并对其发展趋势进行了展望。     

衬底温度及蒸发条件对有机光电探测器性能的影响

为了深入研究p型Si衬底的有机光电探测器的工艺条件对器件光电性能的影响,本文利用Dektak-8型α台阶仪及高分辨率Topometrix Exptorer型原子力显微镜(AFM),对不同衬底温度及蒸发条件下沉积的有机薄膜表面厚度进行了测量;采用拓扑和侧向力接触两种模式,对其表面形貌及其变化规律进行了研究;对制成的光电探测器的光电性能进行了测试分析。结果表明,PTCDA在p-Si(100)表面形成的多晶薄膜呈岛状形态,岛的大小及形貌受制备工艺条件的影响;当衬底温度为50℃、PTCDA的蒸发温度为420℃和蒸发时间为15s时,蒸发薄膜的厚度为135nm;测得器件的最大光电流为92μA,暗电流为7nA。实现了衬底温度及蒸发条件的最佳化。     

水热法制备TiO2纳米晶薄膜的光电性能研究

利用水热法制备了纳米TiO2粉体,分别利用该粉体和经过氢氧化钠溶液水热处理后的粉体涂覆在导电玻璃上制备成薄膜,然后组装为染料敏化太阳能电池.利用XRD和SEM对该薄膜进行表征,并用I-V测试仪对电池的光电性能进行研究.结果表明:未经处理的粉体制备的薄膜粒径小,分布均匀,为纯锐钛矿晶型,组装的电池光电转化效率为4.09%...     

染料敏化太阳能电池改性PEDOT:PSS对电极的制备

通过滚涂法制备了一种掺杂二甲基亚砜(DMSO)和炭黑的改性PEDOT:PSS新型对电极.固定炭黑的加入量,调节PEDOT:PSS与DMSO的比例,用滚涂法制备了不同的薄膜对电极.通过四探针测试仪、扫描电镜、太阳电池测试仪,分别测试了薄膜对电极的方块电阻、表面形貌及其光电性能.结果表明,当PEDOT:PSS溶液与DM-SO的质量比为4.5∶1时,制备的对电极组装的电池性能最佳,短路电流密度为2.12 mA/cm2,开路电压为0.64 V;炭黑的加入使电池的光电转化效率从1.02%提高到1.81%.     

碳纳米管薄膜制备及其光电探测应用进展

光电探测器在遥感、夜视、侦察、医学成像、环境保护和化学检测等方面的应用十分广泛,而光电探测材料的结构与性能直接影响着光电探测器的性能。近年来碳纳米管由其所具有的独特光学和电学性能迅速成长为光电探测中不可或缺的材料。虽然前期研究主要集中在基于单根碳纳米管的光电响应机理研究,但由于未来应用场景中必然是以碳纳米管薄膜为基础的,因而围绕制备大面积、高密度、高取向、高均匀度碳纳米管薄膜,并以此为基础制备光电探测器件成为了近期碳纳米管光电应用领域的研究热点。本文围绕近年来碳纳米管薄膜制备及其在光电探测器件应用这两个方面的进展,分别进行了详尽的介绍和讨论,并展望了碳纳米管薄膜光电探测器的发展趋势。     

The effect of Al electrodes on the nanostructure of poly(3-hexylthiophene): Fullerene solar cell blends during thermal annealing

The presence of Al electrodes on P3HT:PCBM blended thin films significantly modifies the structure of the films during thermal annealing processes used to produce organic photovoltaic cells. In the absence of an Al electrode, thermal annealing produces very thin (0.7 nm) P3HT layers with face-on molecular stacking near the surface of the film and vertically oriented rod-like P3HT crystals in the bulk region with edge-on molecular stacking. Thermal annealing in the presence of an Al electrode makes the preferred orientation of P3HT crystals in the films less prevalent, and Al diffuses into the organic films to form an intermediate layer. The absence of very thin P3HT layers and the less favorable P3HT orientation help to form interpenetrating networks in the organic layer, resulting in better device performance in the films annealed with Al electrodes.     

Fabrication of organic semiconductor crystalline thin films and crystals from solution by confined crystallization

Highly crystalline thin films of organic semiconductors processed from solution for electronic devices are difficult to achieve due to a slow and preferential three-dimensional growth of the crystals. Here we describe the development of a processing technique to induce a preferential two-dimensional crystalline growth of organic semiconductors by means of minimizing one dimension and confining the solution in two dimensions into a thin layer. The versatility of the process is demonstrated by processing small molecules (TIPS-pentacene and C₆₀) and a polymer (P3HT), all from solvents with a relatively low boiling point, to obtain crystalline thin films. The thin films show an improved in-plane packing of the molecules compared to films processed under similar conditions by spin coating, which is beneficial for the use in organic field-effect transistors.     

ZnO缓冲层和退火处理对MgO薄膜结构的影响

采用直流反应磁控溅射法在Si衬底上引入ZnO缓冲层制备了沿(200)晶面择优取向生长的MgO薄膜,然后分别采用快速退火和常规退火两种不同的方式对MgO薄膜进行晶化处理。利用X射线衍射仪(XRD)以及原子力显微镜(AFM)研究了ZnO缓冲层以及两种不同的退火方式对MgO薄膜的结构和形貌的影响。结果表明:具有合适厚度的ZnO缓冲层可以显著地提高MgO薄膜的结晶质量。另外,与快速退火相比,常规退火处理后得到的MgO晶粒均匀圆润,有着较大的(200)衍射峰强度以及较小的表面粗糙度。     

Water-gated organic nanowire transistors

We gated both p-type, and n-type, organic nanowire (NW) films with an aqueous electric double layer (EDL) in thin-film transistor (TFT) architectures. For p-type NWs, we used poly(3-hexylthiophene) (P3HT) NWs grown via two different routes. Both can be gated with water, resulting in TFTs with threshold lower than for conventionally cast P3HT films under the same gating conditions. However, TFT drain currents are lower for NWs than for conventional P3HT films, which agrees with similar observations for ‘dry’ gated TFTs. For n-type NWs, we have grown ‘nanobelts’ of poly(benzimidazobenzophenanthroline) (BBL) by a solvent/non-solvent mixing route with later displacement of the solvent, and dispersion in a non-solvent. Water-gating such films initially failed to give an observable drain current. However, BBL nanobelts can be gated with the aprotic solvent acetonitrile, giving high n-type drain currents, which are further increased by adding salt. Remarkably, after first gating BBL NW films with acetonitrile, they can then be gated by water, giving very high drain currents. This behaviour is transient on a timescale of minutes. We believe this observation is caused by a thin protective acetonitrile film remaining on the nanobelt surface.     

硅基PZT铁电薄膜的制备与性能研究

用溶胶-凝胶（Sol-Gel）方法制备了硅基Pb(Zr0.53Ti0.47)O3(PZT)铁电薄膜。分析了PZT铁电薄膜的表面形貌、晶化程度、界面状态等性质。基于上述分析结果提出并实现了低温退火处理制备有PT过渡层的PZT铁电薄膜的工艺流程。测试了低温制备的PZT铁电薄膜的C-V、漏电等电性能,发现在Sol-Gel法制备PZT铁电薄膜的工艺中加入PT过渡层,有助于提高PZT薄膜的品质。     

Spontaneous growth by sol-gel process of low temperature ZnO as cathode buffer layer in flexible inverted organic solar cells

In this study, the sol–gel method was employed to prepare zinc oxide (ZnO) thin films as cathode buffer layers for inverted organic solar cells (IOSCs). We used a low temperature sol-gel process for the synthesis of ZnO thin films, in which the molar ratio of zinc acetate dihydrate (ZAD) to ethanolamine (MEA) was varied; subsequently, using the thin films, we successfully fabricated inverted solar cells on flexible plastic substrates. A ZnO sol–gel was first prepared by dissolving ZAD and MEA in ethylene glycol monomethyl ether (EGME). The molar ratios of ZAD to MEA were set as 1:1.2, 1:1, and 1:0.8, and we investigated the characteristics of the resulting ZnO thin films. We investigated the optical transmittance, surface roughness, and surface morphology of the films. Then, we discussed the reasons about the improvement of the device efficiency. The devices were fabricated using the ZnO thin films as cathode buffer layers. The results indicated that the morphology of the thin films prepared using the ZAD to MEA ratios of 1:1 and 1:0.8 changed to a rippled nanostructure after two-step annealing. The PCE was enhanced because of the higher light absorption in the active layer caused by the nanostructure. The structure of the inverted device was ITO/ZnO/P3HT:PC₆₁BM/MoO₃/Ag. The short-circuit current densities (8.59 mA/cm² and 8.34 mA/cm²) of the devices with films prepared using the ZAD to MEA ratios of 1:1 and 1:0.8 ratios, respectively, and annealed at 125 °C were higher than that of the device containing the ZnO thin film that was annealed at 150 °C. Inverted solar cells with ZnO films that were prepared using the ZAD to MEA ratios of 1:1 and 1:0.8 and annealed at 125 °C exhibited PCEs of 3.38% and 3.30%, respectively. More than that, PCEs of the flexible device can reach up to 1.53%.     

MgO缓冲层对Si衬底上制备Fe3Si薄膜性能的影响

采用磁控溅射方法和热加工工艺在n型Si衬底上溅射不同厚度的MgO层并制备Fe-Si薄膜层,退火后形成Fe3Si/MgO/Si多层膜结构.利用MgO缓冲层对退火时Si衬底扩散原子进行屏蔽,并分析MgO层对Fe3Si薄膜结构和电学性质的影响.通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和四探针测试仪对Fe3Si薄膜的晶体结构、表面形貌、断面形貌和电阻率进行表征与分析.研究结果表明:当MgO层厚度为20 nm时生成Fe0.9Si0.1薄膜,当厚度为50,100,150和200 nm时都生成了Fe3Si薄膜,生成的Fe3Si和Fe0.9Si0.1薄膜以(110)和(211)取向为主.随MgO缓冲层厚度增加,Si衬底扩散原子对Fe3Si薄膜的影响减小,Fe3 Si薄膜的晶格常数逐渐减小,晶粒大小趋向均匀,平均电阻率呈现先增大后减小趋势.研究结果为后续基于Fe3 Si薄膜的器件设计与制备提供了参考.     

衬底负偏压及溅射功率对SiO_2/Cu薄膜形貌的影响

采用射频磁控溅射镀膜技术,分别以不同的衬底负偏压和射频溅射功率下在p型Si(100)基片上制备了SiO2/Cu薄膜。用原子力显微镜(AFM)对薄膜的表面形貌进行扫描分析,实验结果表明,衬底负偏压和射频溅射功率对SiO2/Cu薄膜的表面形貌都有显著的影响。衬底负偏压在0～15 V内,薄膜表面颗粒尺寸和均方根粗糙度都随着衬底负偏压的增大呈减小的趋势,而溅射功率在100～200 W内,薄膜表面颗粒尺寸和均方根粗糙度都随溅射功率的升高呈增大的趋势。成膜初期是层状生长模式,后期为岛状生长模式,整个成膜过程是典型的层岛生长模式。     

Al_2O_3过渡层厚度对AZO薄膜性能的影响研究

采用磁控溅射法,在预先沉积了Al2O3过渡层的玻璃衬底上制备了性能优良的AZO薄膜。借助XRD、AFM、四探针仪和分光光度计对AZO薄膜的结构、表面形貌以及电学和光学性质进行了表征,并研究了Al2O3过渡层厚度对AZO薄膜性能的影响。结果表明:Al2O3过渡层的添加对AZO薄膜的表面形貌有一定影响;AZO薄膜的结晶质量随着过渡层厚度的增加先上升后下降;AZO薄膜的电阻率因过渡层的添加而明显降低,特别是在AZO薄膜较薄时;在添加了1～3 nm厚的过渡层后,160 nm厚的AZO薄膜的电阻率下降了44%左右;AZO薄膜的可见光透射率和光学带隙基本不受过渡层影响。