Surface Oxidation as a Cause of High Open‐Circuit Voltage in CdSe ETA Solar Cells

TiO₂/CdSe/CuSCN extremely thin absorber (ETA) solar cells are found to give relatively high values of open‐circuit voltage (>0.8 V) but low currents upon annealing the cadmium selenide (CdSe) in air (500 ºC). Annealing in N₂ produces much lower photovoltages and slightly lower photocurrents. Band structure measurements show differences between the two annealing regimes that, however, appear to favor the N₂‐annealed CdSe. On the other hand, chemically resolved electrical measurements (CREM) of the cells reveal marked differences in photo‐induced charge trapping, in particular at absorber grain boundaries of the air versus N₂‐annealed systems, correlated with the formation of Cd–O species at the CdSe surface. Using transient absorption and photovoltage decay, pronounced lifetime differences are also observed, in agreement with the strong suppression of charge recombination. The results point to a multiple role of grain surface‐oxidation, which both impedes electron injection from the CdSe to the TiO_2, but, much more significantly, enhances hole injection to the CuSCN via passivation of hole traps that act as efficient recombination centers.     

铝及铝合金表面氟铝酸盐转化处理技术研究进展

综述了铝及铝合金表面环保节能无铬钝化处理技术的应用现状,包括氟钛酸盐转化技术、氟锆酸盐转化技术、硅酸盐和氟硅酸盐转化技术。并对其今后的应用前景进行了简述。     

基于纳米SiO2改性的镀锌薄板表面无铬耐指纹钝化技术

通常采用无铬耐指纹钝化表面处理手段提高镀锌板表面的耐指纹性能、耐腐蚀性能、自润滑性能和导电性能。结合国内外的相关研究结果,本文主要概述了耐指纹钝化的研究状况以及无铬耐指纹钝化液的主要组分,并对各组分的作用进行了介绍。功能性纳米填料一纳米SiO2,是使无铬钝化液具有耐指纹性的主要因素,其制备以及表面改性一直是耐指纹钝化的研究重点,本文对其制备及改性进行了详细论述,并对无铬耐指纹钝化发展前景进行展望。     

Sputtered oxides used for passivation layers of amorphous InGaZnO thin film transistors

Four sputtered oxide films (SiO₂, Al₂O₃, Y₂O₃ and TiO₂) along with their passivating amorphous InGaZnO thin film transistors (a-IGZO TFTs) were comparatively studied in this paper. The device passivated by an Al₂O₃ thin film showed both satisfactory performance (μ_FE=5.3 cm²/V s, I_on/I_off>10⁷) and stability, as was probably related to smooth surface of Al₂O₃ thin films. Although the performance of the a-IGZO TFTs with a TiO₂ passivation layer was also good enough (μ_FE=3.5 cm²/V s, I_on/I_off>10⁷), apparent V_th shift occurred in positive bias-stress tests due to the abnormal interface state between IGZO and TiO₂ thin films. Sputtered Y₂O₃ was proved no potential for passivation layers of a-IGZO TFTs in this study. Despite unsatisfactory performance of the corresponding a-IGZO TFT devices, sputtered SiO₂ passivation layer might still be preferred for its high deposition rate and excellent transparency which benefit the mass production of flat panel displays, especially active-matrix liquid crystal displays.     

Low cost surface passivation for p-type mc-Si based on pseudobinary alloys (Al2O3)x(TiO2)1−x

The conventional process for back side passivation with full face Al screen printing layer is not suitable for very thin multicrystalline (mc-Si) solar cells and approaches to new technological processes are searched for. More investigations have been concentrated on local aluminum contacts and passivation coatings with different layers on mc-Si wafers. The aim of this work is to prove that (Al₂O₃)_x(TiO₂)_1−x is one promising candidate to be applied as passivation layer on multicrystalline Si. Investigations were performed on dielectric films of pseudobinary alloy (PBA) (Al₂O₃)_x(TiO₂)_1−x, prepared by chemical solution deposition known initially as sol–gel method. It was determined that their optical, dielectric and electrophysical properties are suitable for applications of these layers as back side surface passivation for thin multicrystalline silicon cells.     

PERL硅太阳电池的性能及结构特点

报道了ＰＥＲＬ硅太阳电池的研制结果，在ＡＭ１．５、２５℃条件下，电池效率η＝２３．７６％。阐述其结构设计上的主要特点，并分析了高性能的机理。     

Hydrogen passivation of defects in polycrystalline silicon solar cells

The investigations of hydrogen passivation of defects in polycrystalline silicon produced by the Czochralski method have been carried on. The results presented give evidence that it is advisable to use this material to create cheap effective solar cells.     

PECVD对硅材料的钝化作用

该文通过实验 ,发现对硅片采用双层钝化体系SiO2 /SiNx 可降低表面复合速度到S <1cm/s;而在采用PECVD钝化的过程中 ,最重要的影响因素是FGA的温度 ,退火温度越低越好 ;最后分析了H原子对硅片钝化的微观机理。