Fabrication and thermo stability of the SnO2/Ag/SnO2 tri-layer transparent conductor deposited by magnetic sputtering

Using the magnetic sputtering technique, the SnO₂/Ag/SnO₂ tri-layer transparent films were fabricated on float glasses successfully. Compared with the commercial FTO (F-doped SnO₂) film, the SnO₂/Ag/SnO₂ tri-layer films have higher visible-light transmittance and better conductivity. The total thickness of the SnO₂/Ag/SnO₂ films is one third of the commercial FTO film leading to the high visible-light transmittance. The high carrier concentration of the SnO₂/Ag/SnO₂ films contributes to the tri-layer films’ low resistivity. In addition, to further improve the performance of the SnO₂/Ag/SnO₂ tri-layer films, samples were annealed under different temperatures. The results illustrate that the lowest sheet resistance (5.92 Ω/sq) and the highest visible-light transmittance (87.0%) were obtained after annealing at 200 °C. Furthermore, the thermal stability of the films could be enhanced by a multi-step annealing process due to the recrystallization effect.     

Heat-resisting TCO films for PV cells

We developed new heat-resisting transparent conductive oxide (TCO) films with resistivity of 1.4×10⁻⁴ Ω cm, an optical transmittance of above 80% (at 550 nm) and heat-resisting temperature at above 600 °C. The TCO films consists of fluorine-doped tin oxide films coated on indium–tin oxide films. They were prepared by a spray pyrolysis deposition method on glass substrates. The 100×100 mm² dye-sensitized solar cells (DSCs) were prepared with the TCO films. An energy conversion efficiency of the DSC was improved drastically in comparison to the case with conventional TCO films.     

Patent search on biologics as potential biosimilar candidates

The biological pharmaceutical market is one of the fastest growing sectors in the health care business. Sales of biologic drugs reached $120 billion in 2008 [1] and the worldwide market of biologics continues to grow (IMS Health). As patents on first generation of biologic drugs, including epoetin, insulin granulocyte colony-stimulating factor (G-CSF) and interferon alpha, will soon expire, if they have not already, and patents on some of the second generation of biological drugs, such as antibody drugs, are going to be expire in the next few years, there exists a great opportunity in developing biosimilars, especially for large pharmaceutical companies which face great challenges in developing new blockbuster drugs. In the past few years, the United States, Canada, and Japan have debated or passed legislation on biosimilars with active involvement from top pharmaceutical and generic drug companies. The successful leader in this field will be the one that has the foresight and resources to position themselves well to gain in the future. So what are biosimilars? What are the technological differences between biosimilars and small molecule generic drugs? Finally, what are the considerations for biosimilars in terms of patent searching? An example on a biosimilar study is given here.     

Organic photovoltaic devices based on polythiophene films electrodeposited on FTO substrates

We investigated photovoltaic devices based on electrochemically deposited monolayer of neat polythiophene (PT) films onto fluorine-doped tin oxide (FTO)/glass substrates. The photo-electrical behavior of these devices, using FTO and aluminum as electrodes, presented symbatic and antibatic response. These devices presented V_oc700 mV, under monochromatic irradiation (λ=610 nm; 1 W/m²) and the Incident Photon Converted to Electron Efficiency (IPCE) around 5%, with illumination through the FTO electrode (λ=610 nm; 1 W/m²). Cyclic voltammogramms and optical measurements were used to estimate the PT HOMO and LUMO energy levels, as well to demonstrate that the potential synthesis did not produce any polymer degradation. Using the Schottky model expression in the dark current voltage characteristics it was possible to obtain the barrier height value (_b), for the interface PT/Al. The _b was quite near to the difference between the aluminum work function and the PT electronic affinity and coherent with the V_oc values.     

Ultrasonic-vibration-assisted laser annealing of fluorine-doped tin oxide thin films for improving optical and electrical properties: Overlapping rate optimization

An ultrasonic-vibration-assisted laser annealing method was developed to enhance the performance of fluorine-doped tin oxide (FTO) thin films. The influences of ultrasonic vibration, laser scan line overlapping rate (L_OR) and laser spot overlapping rate (S_OR) on surface morphology, FTO layer thickness, RMS roughness, crystal structure and photoelectric properties of the FTO films were investigated. The results indicated that the presence of ultrasonic vibration during laser annealing could significantly enhance the film compactness, and using moderate L_OR and S_OR values resulted in significantly decreased FTO layer thicknesses and RMS roughnesses as well as slightly increased crystallite sizes, thus yielding significantly improved optical transmittance values and slightly enhanced electrical conductivity values. It was found that the optimal L_OR and S_OR values for ultrasonic-vibration-assisted laser annealing of the FTO films were 80% and 90%, respectively. The as-obtained film possessed the best overall photoelectric property with an average transmittance (400–800?nm) of 85.9%, a sheet resistance of 8.7?Ω/sq and a figure of merit of 2.51?×?10^–2 Ω^–1. This work may be of great significance in terms of performance optimization of transparent conducting oxide (TCO) thin films.     

Enhancement of photoelectrochemical properties with α–Fe2O3 on surface modified FTO substrates

Despite a number of favorable properties, several drawbacks need to be addressed before hematite can be considered a highly desirable material for applications in water-splitting photoelectrochemical (PEC) electrodes. In the present work, the PEC performance was improved by the synergetic effects of the preparation techniques and modification of the fluorine-doped tin oxide (FTO) glass. The hematite photoanodes deposited onto the pretreated FTO supports clearly decreased the overpotential by up to 100 mV with a higher photocurrent compared to the bare FTO glass. In particular, an electrochemical preparation method including moderate annealing resulted in a highly enhanced PEC performance by influencing the FTO glass during the electrode preparation process.     

FTO/ITO复层导电薄膜的研究

采用溶胶凝胶法与溶液水解法分别制备ITO、FTO以及FTO/ITO复层导电膜,利用分光光度仪测量在可见光范围内的透光率,用四探针法精确测量薄膜的电阻率,通过扫描电镜观测薄膜的表面形态,微观颗粒形貌以及薄膜的厚度。实验表明,用SnCl4.5H2OI、n(NO3)3.4.5H2O、NH4F作为主要原料,通过溶胶凝胶法和溶液水解法可制备出低电阻率,高透光性的FTO/ITO复合导电薄膜。     

Increase in photovoltaic performances of dye-sensitized solar cells—Modification of interface between TiO2 nano-porous layers and F-doped SnO2 layers

In order to improve the physical and chemical contacts between a porous TiO₂ layer and an F-doped SnO₂ transparent conductive layer (FTO), the surface of the FTO layer is polished. After polishing, the surface roughness decreased. However, light transmittance and sheet resistance did not vary largely. The short circuit current (J_sc) and efficiencies increased after the FTO was polished. It was found that the interfacial charge transfer between a TiO₂ layer and an FTO layer decreased by impedance measurement, which suggests that contacts between an FTO and a TiO₂ layer are improved because of the flatted surfaces or removal of electrical impurities. We propose one of the industrially important phenomena that surface polishing of FTO is one of the ways to increase photovoltaic performances for DSCs.     

Transparent Conducting Electrodes for Quantum Dots Light Emitting Diodes

In this review, we briefly describe a recent research development of transparent conducting electrodes (TCEs) for next‐generation quantum dot‐based light‐emitting diodes (QDLEDs). Although sputtered Sn‐doped In₂O₃ (ITO) and chemically grown F‐doped SnO₂ (FTO) electrodes have mainly been employed as transparent electrodes for QDLEDs, there have been great advances in TCE materials and fabrication processes. This review presents important characteristics of various TCE and applications in QDLEDs as a transparent cathode or anode. In particular, we will focus on characteristics of metal grids, metal nanowire, carbon nanotube, graphene, and hybrid electrodes for QDLEDs as promising alternatives to typical ITO and FTO electrodes. In addition, we discuss the current status of transparent conducting oxide‐based QDLEDs. By comparing the performances of QDLED with different TCEs, we suggest promising alternatives ITO or FTO electrodes.