低温高速率沉积非晶硅薄膜及太阳电池

采用射频等离子体增强化学气相沉积(RF-PECVD)技术,保持沉积温度在125℃制备非晶硅薄膜材料及太阳电池。在85 Pa的低压下以及400～667 Pa的高压下,改变Si H4浓度和辉光功率等沉积参数,对本征a-Si材料的性能进行优化。结果表明,在高压下,合适的Si H4浓度和压力功率比可以使a-Si材料的光电特性得到优化,并且薄膜的沉积速率得到一定程度的提高。采用低压低速和高压高速的沉积条件,在125℃的低温条件下制备出效率为6.7%的单结a-Si电池,高压下本征层a-Si材料的沉积速率由0.06～0.08 nm/s提高到0.17～0.19 nm/s。     

空气对HAC太阳电池晶体硅/本征非晶硅界面污染情况分析

采用热丝CVD法在N型体硅上以全程真空环境镀膜与IN镀膜后破真空再镀IP的不同形式,分别生长IN-IP非晶硅膜层,用WCT-120对薄膜钝化性能进行分析,并用wxAMPS软件模拟样品电池效率.比对结果表明:全程真空环境镀膜样品的反向饱和电流密度(J0)和理论开压(iVOC)分别为5.12×10-15A·cm-2和0.7...     

ITO/NPB/Alq_3/LiF/Al电致发光器件光电特性

针对有机电致发光器件发光效率低、稳定性差的问题,设计制备了ITO/NPB/Alq3/LiF/Al多层有机电致发光器件.测试了器件的电流电压特性、器件的亮度电压特性、器件的电致发光光谱.结果表明,当外加电压为16V时,器件的电流达到最大值21.70mA,器件的亮度达到了11 700cd/m2;当外加电压为14 V时,电致发光光谱波峰位于528 nm处,归一化强度最大值为0.522 1a.u.制备的器件电子注入能力、电流和亮度均得到了增强.     

混凝土中骨-浆界面断裂韧度的分布特性

在已有的断裂准则和试验数据的基础上，运用概率断裂力学与数理统计的基本理论和方法，对粗骨料与硬化水泥浆体界面断裂韧性的分布特性进行了研究，并提出了确定断裂韧性试验最少件数的途径。由于Weibull分布或对数正态分布常用来分析寿命分布问题，故优先考虑这2种模型。通过分析和计算得出：粗骨料与硬化水泥浆体界面断裂韧性服从对数正态分布，在置信度为0．9，相对偏差不超过5％的条件下，对应的断裂韧性最少件数估计在13件左右。通过断裂韧性分布特性的研究，将为粗骨料与硬化水泥浆体界面概率断裂分析与施工控制提供了参考依据。     

n/p型掺杂非晶硅薄膜工艺优化研究

掺杂层与硅片衬底形成发射极和后背场,掺杂层薄膜质量是影响高效率太阳电池的重要因素之一。以载玻片为衬底沉积掺杂薄膜层后样品电阻为依据对太阳能电池n/p型掺杂非晶硅薄膜主要工艺进行优化。结果表明,n型掺杂非晶硅薄膜最优工艺为电流20.5 A,气压4.0 Pa,气体流量比H2:Si H4:PH3=50∶2∶4(sccm);p型掺杂层非晶硅薄膜最优工艺为电流23.5 A,气压5.5 Pa,气体流量比Si H4∶H2∶B2H6=2∶50∶4(sccm),沉积时间为30min,温度为200℃。     

Banach空间中（p,Y）-算子框架的稳定性

利用算子理论的方法研究了（p,Y）-算子框架的稳定性,给出了（p,Y）-算子框架的几个重要的扰动结果。     

华北电力大学谭占鳌教授课题组在聚合物太阳电池电极界面研究方面取得新进展

正日前,国际著名物刊Scientific Reports刊发了我校谭占鳌教授课题组的论文,题目为:"High performance polymer solar cells with as-prepared zirconium acetylacetonate film as cathode buffer layer"。以共轭聚合物、富勒烯等为代表的碳基半导体材料和器件已形成一个由化学、物理、信息电子和材料科学等诸多学科相互交叉的新兴研究领域,是目前国际上极具挑战性的重要研究方向,特别是在     

M－40／酚醛环氧复合材料界面改性的研究

应用阳极氧化法对Ｍ—４０高模量碳纤维进行表面改性，在酚醛环氧树脂中加入ＱＹ８９１１—Ⅰ型双马来酰亚胺树脂进行基体改性。测定了几种不同体系的Ｍ—４０／酚醛环氧复合材料在室温和高温（１６０℃）的层间剪切强度和抗冲击强度，并用ＳＥＭ观察分析了剪切和冲击断口形貌。结果表明，纤维和基体同时改性的复合材料不仅具有较高的界面强度，而且具有较好的冲击韧性。     

铁对 C/Cu 复合材料界面特性影响的研究

利用电子显微及X射线衍射仪分析研究了C/Cu复合材料的界面特性及合金元素铁对C/Cu复合材料界面特性的影响.研究表明复合材料界面既无化学反应也无扩散发生,C/Cu界面是物理结合.试验表明,合金元素Fe与碳纤维发生化学反应,使C-Cu界面结合强度明显提高,因此使C/Cu复合材料的强度从592MPa提高到696MPa,横向剪切强度从64MPa提高到84MPa.化学结合型界面是提高复合材料强度的途径之一.     

Fabrication and characterization of amorphous ITO/p-Si heterojunction solar cell

Amorphous indium-tin-oxide(a-ITO) film was deposited by radio-frequency(RF) magnetron sputtering at 180°C substrate temperature on the texturized p-Si wafer to fabricate a-ITO/p-Si heterojunction solar cell.The microstructural,optical and electrical properties of the a-ITO film were characterized by XRD,SEM,XPS,UV-VIS spectrophotometer,four-point probe and Hall effect measurement,respectively.The electrical properties of heterojunction were investigated by I-V measurement,which reveals that the heterojunction shows strong rectifying behavior under a dark condition.The ideality factor and the saturation current density of this diode are 2.26 and 1.58×10-4 A cm-2,respectively.And the value of IF/IR(IF and IR stand for forward and reverse currents,respectively) at 1 V is found to be as high as 21.5.For the a-ITO/p-Si heterojunction solar cell,the a-ITO thin film acts not only as an emitter layer,but also as an anti-reflected coating film.The conversion efficiency of the fabricated a-ITO/p-Si heterojunction cell is approximately 1.1%,under 100 mW cm-2 illumination(AM1.5 condition).And the open-circuit voltage(Voc),short-circuit current density(J SC),filll factor(FF) are 280 mV,9.83 mA cm 2 and 39.9%,respectively.Because the ITO film deposited at low temperature is amorphous,it can effectively reduce the interface states between ITO and p-Si.The barrier height and internal electric field,which is near the surface of p-Si,can effectively be enhanced.Thus we can see the great photovoltaic effect.     

Si基薄膜太阳电池绒面ZGO透明导电膜的研究

采用孪生对靶直流磁控溅射的方法在室温下制备高质量的Ga掺杂ZnO(ZGO)透明导电薄膜,用HCl腐蚀的方法获得满足光散射特性的绒面ZGO薄膜。制备的ZGO样品为具有六角纤锌矿结构的多晶膜,具有(002)方向的择优取向。腐蚀后,绒面ZGO薄膜的晶粒度减小,电阻率基本不变。在可见光范围内,绒面ZGO的反射率比平面ZGO的反射率下降了10%左右。将绒面ZGO薄膜应用于p-i-n型非晶Si薄膜太阳电池中,有效提高了太阳电池性能,使得电池的短路电流提高到17.79 mA/cm2,电池的转换效率增加到7.23%。     

a-Si/μc-Si叠层电池中间层材料SiO_x:H制备研究

为提高a-Si/μc-Si叠层太阳电池的效率,采用射频等离子体增强化学气相沉积(RF-PECVD)技术,制备了系列n型掺磷硅氧(SiOx:H)薄膜作为中间层,研究了CO2/Si H4气体流量比、沉积功率和PH3掺杂浓度等工艺参数对材料光电特性的影响,获得了折射率、电导率和禁带宽度能够在较大范围内调控的SiOx:H薄膜。     

非、单晶硅太阳能电池组件比功率发电量比较

为测试非晶硅和单晶硅太阳能电池组件的实际发电能力,设计了由电子模拟负载和直流安时计组成的发电量测量装置,对两种太阳能电池组件的发电量进行实验测试比较.提出比功率发电量这一物理量,直观表达太阳能电池组件的发电性能.实验表明,在晴天直射强光和阴雨天弱散射光环境下,非晶硅太阳能电池板的比功率发电量均大于单晶硅.     

ITO/Ag/ITO透明导电膜性能研究进展

复合型透明导电膜ITO/Ag/ITO是一种极具发展潜力的高性能透明导电膜,其导电性远高于传统透明导电材料氧化铟锡(ITO),同时可大幅节约ITO膜中的稀缺元素In。文章阐述了ITO/Ag/ITO复合膜的设计原理及其设计中存在的问题,分析了ITO/Ag/ITO结构中底层ITO膜、外层ITO膜和Ag膜在膜系结构中的作用及其对ITO/Ag/ITO光学和电学性能的影响,阐明了Ag膜对ITO/Ag/ITO光学和电学性能的决定性作用,综述了对Ag膜进行退火处理、添加其他金属元素、引入超薄层等提高Ag膜沉积质量和性能的方法,展望了高性能ITO/Ag/ITO复合透明导电膜今后的研究方向。     

A new type counter electrode for dye-sensitized solar cells

A new type counter electrode for dye-sensitized solar cells (DSCs) was proposed which consists of substrate, aluminum film and platinum film. The new type counter electrode can obviously improve the photoelectric conversion efficiency of DSCs from 3.46% to 7.07% under the standard AM1.5 irradiation condition. Advantages and shortcomings of this new type counter electrode in terms of electrical properties, optical properties and anti-corrosive properties were analyzed. As a result, some improvements were proposed. Supported by the Key Foundation for Fundamental Research of Tianjin Municipal Science & Technology Commission in China ( Grant No. 06YFJZJC01700) and the National Basic Research Program of China (“973“ Project) (Grant Nos. 2006CB20260, 2006CB202603)     

多晶Si太阳电池新型制绒工艺研究

提出一种采用二次酸腐蚀的多晶Si制绒新方法,首先在HF/HNO3的富HNO3体系中对Si片进行一次腐蚀,之后在富HF体系中进行二次腐蚀,以优化表面织构,减少光在Si表面的反射损失。制绒后,用扫描电子显微镜(SEM)对Si片进行了表面形貌分析,用Carry 5000紫外-可见-近红外分光光度计测量反射谱线,得到未镀减反射膜(ARC)的二次腐蚀制绒的最低反射率为20.34%,比一次腐蚀制绒(22.70%)低2.36%。将二次腐蚀新工艺应用于太阳电池工业制备中,对电池输出参量进行检测分析。结果表明,经过二次腐蚀工艺处理的太阳电池开路电压(VOC)、短路电流(JSC)和效率η均比采用一次腐蚀工艺的太阳电池有不同程度的提高,制成的太阳电池最高效率为14.93%。     

Effect of interface layers on electron field emission properties of amorphous diamond films

Hydrogen-free high sp~3 content amorphous diamond (AD) films are deposited on three different substrates——Au-coated Si (Au/Si), Ti-coated Si (Ti/Si) and Si wafers. Electron field emission properties and fluorescent displays of the above AD films are studied by using a sample diode structure. The compositional profile of the interfaces of AD/Ti/Si and AD/Si is examined by using secondary ions mass spectroscopy (SIMS). Because of the reaction and interdiffusion between Ti and C, the formation of a thin TiC intermediate layer is possible between AD film and Ti/Si substrate. The field emission properties of AD/Ti/Si are sufficiently improved, especially its uniformity. A field emission density of 0.352 mA/cm~2 is obtained under an electric field of 19.7 V/μm. The value is much more than that of AD/Au/Si and AD/Si under the same electric field.     

Depth profile study on Raman spectra of high-energy-electron-irradiated hydrogenated amorphous silicon films

According to the different penetration depths for the incident lights of 472 nm and 532 nm in hydrogenated amorphous silicon (a-Si:H) thin films, the depth profile study on Raman spectra of a-Si:H films was carried out. The network ordering evolution in the near surface and interior region of the unirradiated and irradiated a-Si:H films was investigated. The results show that there is a structural improvement in the short- and intermediate-range order towards the surface of the unirradiated a-Si:H films. The amorphous silicon network in the near and interior region becomes more disordered on the short- and intermediate-range scales after being irradiated with high energy electrons. However, the surface of the irradiated films becomes more disordered in comparison with their interior region, indicating that the created defects caused by electron irradiation are concentrated in the near surface of the irradiated films. Annealing eliminates the irradiation effects on a-Si:H thin films and the structural order of the irradiated films is similar to that of the unirradiated ones after being annealed. There exists a structural improvement in the short- and intermediate-range order towards the surface of the irradiated a-Si:H films after being annealed. Supported by the National Outstanding Young Scientists Foundation of China (Grant No. 60425101) and the Science Foundation of General Armament Department of China (Grant No. 06DZ02)