SQM-OTFT: A compact model of organic thin-film transistors based on the symmetric quadrature of the accumulation charge considering both deep and tail states

A physically-based compact model of organic thin-film transistors suitable for CAD simulators is proposed. It is worked out by means of a newly developed and particularly simple form of the charge-sheet model: the symmetric quadrature of the accumulation charge. The model is based on the variable-range hopping and accounts for both deep and tail states. It is simple, symmetric, accurately accounts for the below-threshold, linear, and saturation regimes via a unique formulation. The symmetric quadrature is accurate within 5% in all regions of operation and the resulting current model is suitable both for p- and n-type transistors. The model leads to a significant simplification of the drain current and of the quasi-static expressions of the terminal charges based on the Ward–Dutton partition. Finally, the symmetric quadrature leads to an explicit and analytically tractable solution for the surface potential as a function of position in the device channel that can be extremely useful to implement advanced physical effects.     

Crosslinked polymer-mixture gate insulator for high-performance organic thin-film transistors

In this paper, we report on the fabrication of a crosslinked polymer-mixture gate insulator for high-performance organic thin-film transistors (TFTs). We used cyanoethylated pullulan (CEP) as a crosslinkable high-k polymer matrix and poly(ethylene-alt-maleic anhydride) (PEMA) as a polymeric crosslinking agent. Because PEMA has a high number of functional groups reactive to the hydroxyl groups of CEP, the use of PEMA is effective for minimizing the amount of remaining hydroxyl groups strongly related to the large current hysteresis and high off current of the organic TFTs. To investigate the potential of the CEP-PEMA mixture as a gate insulator, we fabricated 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C₈-BTBT) TFTs. The C₈-BTBT TFT with the 60 nm-thick CEP-PEMA gate insulator showed excellent TFT performance with a field-effect mobility of 1.4 cm²/V s and an on/off ratio of 2.4 × 10⁶.     

Numerical investigation of a double-junction a:SiGe thin-film solar cell including the multi-trench region

We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new multi-trench region in the intrinsic layer, in order to modulate the total resistance of the solar cell. Based on 2-D numerical investigation and optimization of amorphous SiGe double-junction (a-Si:H/a-SiGe:H) thin film solar cells, in the present paper numerical models of electrical and optical parameters are developed to explain the impact of the multi-trench technique on the improvement of the double-junction solar cell electrical behavior for high performance photovoltaic applications. In this context, electrical characteristics of the proposed design are analyzed and compared with conventional amorphous silicon double-junction thin-film solar cells.     

N掺杂TiO_2/Ti液膜光催化处理染料废水

以尿素为氮源,采用溶胶-凝胶法制备了N掺杂Ti O2膜电极(N-Ti O2/Ti),并优化了制备条件。结果表明,n(N)∶n(Ti)=0.84∶1、经450℃煅烧2.5 h制得的膜电极光催化性能最佳;与Cu电极组装斜置双极液膜反应器,可见光下考察光催化反应的影响因素。得出最佳降解条件为:初始p H=2.50,废水流量为85 m L/min,Na2SO4质量浓度为0.5 g/L,此条件下处理20 mg/L苋菜红120 min,脱色率可达90.1%;膜电极的重现性与重复性结果表明,6片电极60 min的脱色率为78.1%±4.0%;一片电极经6次循环60 min脱色率比初次减少了7.9%。     

寒区相变墙板与电热膜采暖系统的匹配研究

相变储能技术的发展和昼夜电价分时制的实行为电采暖在北方寒区推广应用提供了可行性.数值模拟在初次和稳定蓄放热过程中,相变墙板温度和热流密度随时间变化,研究相变厚度、相变温度和相变半径对相变墙板传热过程的影响规律,并确定出适宜于寒区电热膜采暖系统的相变墙板,使该相变电采暖系统不仅具有热舒适性,而且能将夜间的低价电能储存起来供白天采暖用,降低电采暖系统的运行费,并对电网起到调峰作用,在宏观上具有节能效果.     

基于反向耦合模原理光栅的薄膜模型研究

提出了将Round方法与薄膜理论相结合的多层薄膜模型,将光纤光栅看成一多层薄膜体系,每层薄膜用界面传输矩阵和膜层传输矩阵表示,将每层的传输矩阵相乘后得到光栅的总传输矩阵,用它分析了基于反向耦合模原理的各光纤光栅。数值计算结果表明,该模型计算方法简单,而且和耦合模理论吻合得很好,可以用此模型来分析光纤光栅的各种参数对光栅的影响。     

Thin-film composite forward osmosis membranes with substrate layer composed of polysulfone blended with PEG or polysulfone grafted PEG methyl ether methacrylate

To advance commercial application of forward osmosis (FO), we investigated the effects of two additives on the performance of polysulfone (PSf) based FO membranes: one is poly(ethylene glycol) (PEG), and another is PSf grafted with PEG methyl ether methacrylate (PSf-g-PEGMA). PSf blended with PEG or PSf-g-PEGMA was used to form a substrate layer, and then polyamide was formed on a support layer by interfacial polymerization. In this study, NaCl (1 mol?L⁻¹) and deionized water were used as the draw solution and the feed solution, respectively. With the increase of PEG content from 0 to 15 wt-%, FO water flux declined by 23.4% to 59.3% compared to a PSf TFC FO membrane. With the increase of PSf-g-PEGMA from 0 to 15 wt-%, the membrane flux showed almost no change at first and then declined by about 52.0% and 50.4%. The PSf with 5 wt-% PSf-g-PEGMA FO membrane showed a higher pure water flux of 8.74 L?m⁻²?h⁻¹ than the commercial HTI membranes (6–8 L?m⁻²?h⁻¹) under the FO mode. Our study suggests that hydrophobic interface is very important for the formation of polyamide, and a small amount of PSf-g-PEGMA can maintain a good condition for the formation of polyamide and reduce internal concentration polarization.     

电子束蒸发沉积碲锗铅薄膜的微结构和化学组分研究

为了探寻碲锗铅(Pb_(1-x)Ge_xTe)薄膜的最佳沉积方式,在硅基片上采用电子束蒸发沉积碲锗铅(Pb_(0.78)Ge_(0.22)Te)薄膜。使用X射线衍射(XRD)、电子扫描显微镜(SEM)、能量散射X射线分析(EDAX)等手段对薄膜的微结构和化学配比特性进行了分析。发现碲锗铅薄膜为多晶结构,具有明显的择优取向,晶粒多为矩形,薄膜中未出现其它相关氧化物。与热蒸发膜层相比,电子束蒸发沉积的膜层有更为完善的晶体结构。     

Effect of succinic anhydride as an electrolyte additive on electrochemical characteristics of silicon thin-film electrode

The effect of an electrolyte additive, succinic anhydride (SA), on the electrochemical performances of a silicon thin-film electrode, which is prepared by radio-frequency magnetron sputtering, is investigated. The introduction of SA into a liquid electrolyte consisting of ethylene carbonate/diethyl carbonate/1 M LiPF₆ significantly enhances the capacity retention and coulombic efficiency of the electrode. This improvement in the electrochemical performance of the electrode is attributed to modification of the solid/electrolyte interphase (SEI) layer by the introduction of SA. The differences in the characteristic properties of SEI layers, with or without SA, are explained by analysis with scanning electron microscopy, electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy.     

霍尔无栅离子源的研制及应用

基于离子束辅助镀膜技术,自主研制了一款新型霍尔无栅离子源,利用该离子源,采取离子束辅助沉积方法,在玻璃基底上镀制了多种光学薄膜,并对所镀制光学薄膜的性能进行了测试。测试结果表明:所研制的霍尔无栅离子源制备的各种光学薄膜,其膜层强度、附着性、耐腐蚀性以及光学性质都比常规热蒸发工艺所制得的薄膜有明显改善。