光学薄膜及其发展现状

介绍了传统光学薄膜的原理,并对反光膜、增透膜、纳米光学薄膜等传统光学薄膜的研究现状及应用情况,以及几种新型光学薄膜如高强度激光器、金刚石及类金刚石膜、软X射线多层膜、光电通信用光学薄膜的研究现状及应用进行了详细分析;最后对光学薄膜的发展前景进行了展望。     

聚合物乳液粒子制备纳米多孔增透膜

采用提拉法在载玻片上沉积了PMMA/PS混合乳液粒子,用环己烷选择性地溶解掉表层PS粒子,制备了孔隙率从表向里梯度变化的纳米粒子增透膜,在578 nm处透过率可达99.5%;研究了两种聚合物纳米粒子的比例及环己烷浸泡时间对增透性能的影响。本方法可用于大面积和不规则基材上制备增透膜,并解决了提拉法成膜的粒子堆积紧密、孔隙率低且不易调节的缺点,使粒子膜的透过率大幅度提高。     

晶体硅表面纳米孔减反光结构的制备及其性能表征

利用金属辅助硅化学刻蚀法在晶体硅表面制备 了 大面积有序硅纳米结构,并基于金属辅助硅化学刻蚀的机理,实现了硅纳米结构从线阵列到 孔阵列转变。漫反射光谱的测试结果表 明,相对于平面、金字塔结构,硅纳米孔织构的晶体硅具有卓越的减反光性能,在300100nm 光谱范围内的AM1.5G太阳光子的光反射损失比低于3.6%。硅纳米孔阵列减反光性能优异, 制备方法简单、快速,且其孔壁互连,有益于晶体硅太阳电池的后续制备工艺及其表面结构 机械稳定,可作为减反光结构应用于晶体硅太阳电池。     

Structural and optical properties of a radio frequency magnetron-sputtered ZnO thin film with different growth angles

This study introduces optical properties of a columnar structured zinc oxide [ZnO] antireflection coating for solar cells. We obtained ZnO films of columnar structure on glass substrates using a specially designed radio frequency magnetron sputtering system with different growth angles. Field-emission scanning electron microscopy was utilized to check the growth angles of the ZnO films which were controlled at 0°, 15°, and 30°. The film thickness was fixed at 100 nm to get a constant experiment condition. Grain sizes of the ZnO films were measured by X-ray diffraction. A UV-visible spectrometer was used to measure the transmittance and reflectance of the ZnO film columnar structures as a function of the growth angles.     

Optimum antireflection coatings for heteroface AlGaAs/GaAs solar cells—Part I: The influence of window layer oxidation

This paper details both the theoretical and experimental results of a modified model for designing MgF₂/ZnS double-layer antireflection coatings for AlGaAs/GaAs heteroface solar cells. The main contribution of the model presented is that it takes into account the possible existence of an oxide layer in the AlGaAs window layer. In a first step the optical behavior of the oxide is modeled and that model is used to recalculate optimal double-layer antireflection coating when a thin AlGaAs oxide layer is present. Significant differences with classical double-layer antireflection coating design are found, such as, the antireflection properties of the oxide layer when formed onto originally thick windows or its equivalent role to that of the ZnS layer (as a high refractive index media) in the coating. Finally, an experimental analysis is carried out to assess empirically the conclusions of the model. These experiments have yielded an excellent agreement with the proposed theory.     

Ag surface plasmon enhanced double-layer antireflection coatings for GaAs solar cells

Cs. A new SiO2/Ag-ZnS double-layer coating with better antireflection ability can be achieved if the particle volume fraction in ZnS is 1%-2%.     

Optimum antireflection coatings for heteroface AlGaAs/GaAs solar cells—Part II: The influence of uncertainties in the parameters of window and antireflection coatings

This paper details both theoretical and experimental results of an enhanced model to design MgF₂/ZnS double-layer antireflection coatings for AlGaAs/GaAs heteroface solar cells. The main contribution of this work is that a method for taking technological tolerances or uncertainties into account in the optically relevant parameters for antireflection coating design is presented. This is done by the calculation of contours of quasi-optimum performance for a certain range of variation of the uncertain parameters. A number of experiments testing different aspects of the predictions made by the model are commented on, showing good agreement with the calculated performance. Unwanted window oxidation, described in Part I of this work, has proven to be the key factor influencing quasi-optimum contours.