keV质子辐照Kapton/Al的能量传输过程

采用TRIM和SRIM2003软件模拟计算了10—300keV能量区间质子辐照Kapton/Al的能量传输过程. 依据模拟结果选取了辐照能量参数, 在室温真空条件下, 采用空间综合辐照设备对Kapton/Al进行了质子辐照. 借助于表面红外光谱技术, 对Kapton的重要官能团特征峰做了定量分析, 通过特征峰处吸光度的变化得到了典型分子键的损伤截面. 平均损伤截面和电子能损的强烈依赖关系及TRIM计算结果一致说明keV质子辐照Kapton/Al的辐照损伤主要来自电子能损效应. 太阳吸收比的变化趋势和模拟结果都表明在入射能量80keV附近, 质子辐照Kapton/Al的辐照效应最大.     

keV 质子辐照对Kapton/Al光学性能的影响

 采用空间综合辐照设备对Kapton/Al薄膜进行了质子辐照地面模拟试验，选取质子能量90 keV,辐照通量5.0×10¹¹ cm¹²·s^-1。通过辐照前后光谱反射系数的变化考察了实验样品的光学性能退化特征。借助于反射光谱和紫外-可见吸收光谱和傅里叶转换红外光谱分析技术分析了辐照后Kapton/Al光学性能的退化机理。研究结果表明：辐照过程中样品表面发生了复杂的化学反应，随着辐照剂量的增加光能隙逐渐减小，Kapton吸收曲线的末端边缘发生红移并且在可见光区吸收强度增加。     

电子辐照能量对Kapton/Al热控涂层光学性能的影响

 研究了电子辐照时，电子能量与累积通量对Kapton/Al热控涂层光学性能的影响。采用原位测量的手段记录了辐照前后的光谱反射系数。试验结果表明，电子辐照后Kapton/Al热控涂层的反射性能,在太阳光谱辐射强度较大的300~1 200nm波长区间产生较大程度退化。在电子辐照作用下，作为离子导电型聚合物的 Kapton薄膜表面没有发现辐照充电效应。辐照后涂层材料存在“退火效应”，或称“漂白效应”。Kapton/Al涂层太阳吸收比的变化量与电子辐照累积通量的变化关系成幂函数形式,其系数与指数的极大值与极小值分别出现在电子能量为50keV附近。在辐照累积通量相同时，该变化量随辐照电子能量的提高而增大。     

电子与太阳电磁射线综合辐照对Teflon FEP/Al光学性能的影响

 在30keV的电子、质子单独辐照及电子与太阳电磁射线综合辐照作用下，对Teflon FEP/Al第二表面镜光学性能的演化进行了研究。试验结果表明，在相同辐照通量与能量乘积的情况下，电子与质子单独辐照后Teflon FEP/Al涂层材料的太阳吸收比变化相同，故可用电子与太阳电磁射线综合辐照简化地面模拟加速试验。Teflon FEP/Al光学性能退化动力学曲线可描述成加速系数与辐照时间乘积（称为当量辐照时间）的指数函数形式。在当量辐照时间相同的情况下，太阳吸收比的变化与加速系数无关。     

紫外辐照对聚醚酰亚胺薄膜介电性能的影响北大核心CSCD

研究了不同紫外辐照时间对聚醚酰亚胺(PEI)薄膜介电性能的影响。采用FT-IR和SEM表征了PEI薄膜的分子结构和微观形貌。结果表明,紫外辐照后PEI薄膜在1742cm^(-1)处的吸收峰比原薄膜增大,说明PEI分子链中的C=O基团随辐照时间的增加而增加,并在薄膜表面产生了微裂纹。对PEI薄膜的介电性能进行的研究结果表明,随着紫外辐照时间的增加,PEI薄膜的介电常数和介电损耗增大,而表面电阻率下降,体积电阻率基本不变。并随紫外辐照时间的增加,直流击穿强度呈先增加后降低的趋势,一定辐照剂量可使薄膜发生交联反应,使击穿场强较原薄膜提高20%以上。     

低能质子辐照ZnO/silicone白漆产生微观损伤的红外光谱研究

 通过空间综合辐照模拟设备对能量小于200 keV质子辐照下ZnO/silicone白漆光学性能变化及损伤机理进行研究。结果表明,ZnO/silicone白漆的光学性能退化主要发生在可见光区,太阳吸收比随质子辐照能量、注量的增加而增大。借助傅里叶变换红外光谱分析技术研究了质子辐照ZnO/silicone白漆时有机硅树脂的光学性能退化机理。质子辐照使ZnO/silicone白漆中游离氧含量增加,氧化硅原子上的有机取代基使Si—C链断裂,并生成活性羟基,而这种活性羟基能促使有机硅树脂内Si—O—Si键的裂解。同时Si—O—Si链内氧原子未成键的孤对电子与邻近硅原子的3d空轨道配位,降低了π*轨道的能量,提高了对光吸收的几率,增强了n→π*电子跃迁,使吸收带红移,从而导致ZnO/silicone白漆光学性能退化。     

γ射线作用下氧化铪基MOS结构总剂量效应研究

使用原子层淀积方法得到了7.8 nm厚度的HfO₂薄膜并通过直接溅射金属铝电极得到了Al/HfO₂/Si MOS电容结构,测量得到了HfO₂基MOS结构在60Co γ射线辐照前后的电容-电压特性,使用原子力显微镜得到了HfO₂薄膜在辐照前后的表面微观形貌,使用X射线光电子能谱方法测量得到了HfO₂薄膜在辐照前后的化学结构变化。研究发现,使用原子层淀积方法制备的HfO₂薄膜表面质量较高;γ射线辐照在HfO₂栅介质中产生了数量级为1012 cm-2的负的氧化层陷阱电荷;HfO₂薄膜符合化学计量比,介质内部主要的缺陷为氧空位且随着辐照剂量的增加而增加,说明辐照在介质中引入了陷阱从而导致MOS结构性能的退化。     

真空紫外辐照对MQ增强硅橡胶热性能及光学性能的影响

 采用空间综合辐照模拟设备研究了真空紫外辐照对MQ增强加成型硅橡胶的表面形貌、质量损失、热性能及光学性能的影响。试验结果表明：真空紫外辐照后,硅橡胶表面出现损伤裂纹,随辐照剂量的增加,裂纹的数量增多;真空紫外辐照后,硅橡胶的质量有所损失,其质损率随辐照剂量的增加而增加;真空紫外辐照后硅橡胶的耐热性随辐照剂量的增加先增加而后下降;真空紫外辐照对硅橡胶材料的体膨胀/收缩变形影响不大,但对材料的光学性能有较大影响,随着辐照剂量的增加,材料的光学透过率下降。     

氧掺入对纳米硅薄膜微结构及能带特性的影响

采用等离子体增强化学气相沉积法(PECVD)制备了富硅氧化硅薄膜,利用XRD衍射仪,傅里叶变换红外透射光谱仪以及紫外-可见光分光光度计分析了氧掺入对薄膜微观结构以及能带特性的影响。结果表明,随着氧掺入比(CO₂/SiH₄)的增加,薄膜晶粒尺寸减小,晶化度降低,纳米硅(nc-Si)表面的张应力先增加后减小。红外吸收谱分析表明,氧掺入比增加导致薄膜内氧含量增高,富氧Si—O键合密度增加,富硅Si—O键合密度降低。同时,薄膜结构因子减小,有序度增大,薄膜微观结构得到改善。当氧掺入比大于0.08时,薄膜结构因子增大,有序度降低。此外,氧掺入增加导致薄膜带隙不断增加,带尾宽度呈现先减小后增大的趋势。因此,通过氧掺入可以调节纳米硅薄膜微观结构及能带特性,氧掺入比为0.08时,薄膜具有高晶化度和较宽的带隙,微观结构得到有效改善,可用作薄膜太阳能电池的本征层。     

ZnO薄膜的激光辐照效应研究

研究了KrF准分子激光辐照对ZnO薄膜的本征缺陷.紫外（UV）发光以及表面形貌的影响,并对室温下ZnO的UV发射机理进行了详细探讨.结果表明激光辐照打断了薄膜内Zn—O键,氧空位（锌填隙）增多,导致表面电阻率下降,载流子浓度升高,调节激光辐照能量密度,可在较大范围内调控ZnO薄膜中的施主缺陷浓度;同时在激光热效应作用下,薄膜晶粒熔融长大,表面粗糙度大大降低;室温下ZnO薄膜的UV发光包括自由激子复合发光（FX）及其声子伴线（FX-LO）,缺陷浓度决定了FX与FX-LO的相对强度比,进而影响UV发射峰的强度以及位置.因此,激光辐照可以快速、有效地对ZnO薄膜内的缺陷浓度进行调控,从而控制其室温下的UV发射强度,这对于提高ZnO基光电器件的性能具有重要意义. 关键词： ZnO薄膜 激光辐照 紫外发光 缺陷浓度     

Ultraviolet irradiation induced changes in the surface of phenolphthalein poly(ether sulfone) film

Changes in surface characteristics of phenolphthalein poly(ether sulfone) (PES-C) film induced by ultraviolet (UV) irradiation were investigated. The surface properties of the pristine and irradiated films were studied by attenuated total-reflection FTIR (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), contact angle measurements and atomic force microscopy (AFM). It was found that photooxidation degradation took place on the sample surface after irradiation and the oxygen content in the surface increased as evidenced by FTIR-ATR and XPS results. The water contact angle of the irradiated films decreased with increasing irradiation time, which was ascribed to the increased polarity of the surface induced by photooxidation. The etching of ultraviolet irradiation induced the roughening of PES-C surface after irradiation with its root-mean-square roughness (RMS) determined by AFM increased from 2.097 nm before irradiation to 7.403 nm in the area of 25 μm × 25 μm.     

超声波和紫外光协同降解酸性橙Ⅱ水溶液的机理研究

以含有多个苯环的典型偶氮染料-酸性橙Ⅱ为研究对象,研究了超声波和紫外光分别辐照及共同辐照下的降解现象。酸性橙Ⅱ水溶液在超声波及紫外光分别辐照下均发生显著降解,反应过程符合准一级反应动力学规律。在超声波和紫外光共同辐照下,反应过程也符合准一级反应动力学规律,同时酸性橙Ⅱ水溶液降解呈现显著的声光协同效应,即同一辐照时间内超声波和紫外光共同辐照下酸性橙Ⅱ的降解率大于超声波和紫外光单独辐照下各自降解率之和。动力学分析结果表明,该协同效应可归因于紫外光对超声空化过程中产生的过氧化氢的裂解作用。      

Nanoroughness control of Al-Doped ZnO for high efficiency Si thin-film solar cells

The Al-doped ZnO (ZnO:Al) front transparent conducting oxide (TCO) for high efficiency Si thin-film solar cell has been developed using RF magnetron sputtering deposition and chemical wet etching. Microscopic surface roughness of the as-deposited ZnO:Al film estimated by spectroscopic ellipsometry is closely related to the compactness of the TCO film, and shown to be a straightforward and powerful tool to optimize the deposition conditions for the proper post-etched surface morphology. Wet-etching time is adjusted to form the U-shaped craters on the surface of the ZnO:Al film without sharp etch pits that can cause the crack-like defects in the overgrown microcrystalline Si-absorbing layers, and deteriorate the V_oc and FF of the Si thin-film solar cells. That is to say, the nanoroughness control of the as-deposited TCO film with proper chemical etching is the key optimization factor for the efficiency of the solar cell. The a-Si:H/a-SiGe:H/μc-Si:H triple junction Si thin-film solar cells grown on the optimized ZnO:Al front TCO with anti-reflection coatings show higher than 14% conversion efficiency.     

Effects of atomic oxygen treatment on structures, morphologies and electrical properties of ZnO:Al films

ZnO:Al (ZAO) film has a potential application in providing spacecrafts the protection against atomic oxygen (AO) erosion. To advance the understanding of the AO resisting mechanisms and the relationships between the structures, morphologies and conductive properties of ZAO film, direct current magnetron sputtered ZAO films with different thicknesses were treated with AO in a ground-based simulation facility. The microstructure, surface chemical state, morphologies and electrical properties of pristine films and irradiated ones were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy and Hall measurement. It is found that AO exposure produces novel, oriented recrystallization of the surface particles. It also increases the content of oxygen ions in fully oxidized stoichiometric surroundings on the surface, resulting in the decrease of the conductivity. As the thickness of ZAO film increases, the crystallinity, conductivity and resistance to AO erosion are all improved.     

Erosion of polyimide modified by amorphous silica sol in the stream of oxygen plasma

Polymeric coatings derived from Kapton H polyimide, thermoplastic polyimide (PI), and a composite with amorphous silica sol (PI-SS) were irradiated in a magnetoplasma dynamic accelerator of oxygen plasma simulating the action of atomic oxygen (AO). The volumetric erosion coefficients of polymers were calculated, and the comparative analysis of the stability of coatings was performed. The changes in morphology of polymer surfaces before and after irradiation were studied by means of scanning electron microscopy. It was shown that the PI-SS composite has increased resistance to atomic oxygen. The composition of the PI-SS composite was found at which the particles of silica sol are uniformly dispersed over the polymer volume that explains a better resistance of PI-SS polymeric-inorganic compositions to the action of atomic oxygen. The lowest stability was registered for the coating based on Kapton H polyimide. The surfaces of all coatings after irradiation were found to possess a carpetlike morphology. Each polymer featured a number of distinctive peculiarities of the surface structure caused by the differences in the chemical structure of the polymides under investigation.