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Abstract: Highly transparent conductive Ga-doped ZnO (GZO) thin films have been prepared on glass substrates by metal organic chemical vapor deposition. The effect of Ga doping on the structural, electrical and optical properties of GZO films has been systematically investigated. Under the optimum Ga doping concentration (∼4.9at.%), c-axis textured GZO film with the lowest resistivity of 3.6×10−4 Ωcm and high visible transmittance of 90% has been achieved. The film also exhibits low transmittance (<1% at 2500nm) and high reflectance (>70% at 2500nm) to the infrared radiation. Furthermore, our developed GZO thin film can well retain the highly transparent conductive performance in oxidation ambient at elevated temperature (up to 500°C). [Copyright &y& Elsevier]

Abstract: n-ZnO nanorod/p-CuAlO2 heterojunction light-emitting diodes have been fabricated on p+-Si substrates. The CuAlO2 thin film was deposited by dc-magnetron sputtering while the ZnO nanorods (NRs) were fabricated using the vapor-phase transport method. The current–voltage characteristics of the devices showed good rectifying behavior with a high forward-to-reverse current ratio of around 120 at ±7V. Strong ultraviolet electro-luminescence centered at ∼390nm and a broad green-band emission were observed from the diode at room-temperature. The p-CuAlO2 layer was found to facilitate hole injection from p+-Si into n-ZnO while confining the electrons at ZnO/CuAlO2 interface, thus effectively enhancing the recombination emission efficiency in ZnO NRs. [Copyright &y& Elsevier]

The polycrystalline silicon thin film and gate oxide of poly-Si TFTs were treated by NH3/N2O plasma or their combination to improve the reliability of TFTs. The poly-Si TFTs with and without NH3/N2O plasma treatment were characterized by measuring the transfer curves of poly-Si TFTs. The results showed that the characteristics of poly-Si TFTs treated with NH3/N2O plasma were greatly improved at hot-carrier stress and thermal accelerated tests. The reason is that nitrogen atoms terminate the dangling bonds and improve the characteristics of poly-Si TFTs. [Copyright &y& Elsevier]

Abstract. Three types of silicate phosphor thin films, emitting in the red-green-blue (RGB) primary colors, were fabricated by pulsed laser deposition, including manganese and lead doped calcium silicate (CaSiO[sub 3]:MnPb) for red color, manganese doped zinc silicate (Zn[sub 2]SiO[sub 4]:Mn) for green color and cerium doped yttrium silicate (Y[sub 2]SiO[sub 5] :Ce) for blue color. A correlation was observed between photoluminescence intensity with film crystallinity and surface morphology. RGB phosphor thin films with excellent color saturation were obtained. Luminescence mechanisms for these phosphor thin films are discussed. [ABSTRACT FROM AUTHOR]

This study is on a new approach for fabrication of poly-Si thin films. Aluminum-induced crystallization of a-Si film has been achieved by thermal annealing only at around 400 °C. The Experimental results reveal that the Al on top of a-Si arrangement has more evident effect in crystallization enhancement than that with Al under a-Si, and the resultant poly-Si films show preferred (400) crystal orientation. It is verified that aluminum can cause lateral crystallization of a-Si film. No preferred orientation was noticed from lateral crystallization samples. [ABSTRACT FROM AUTHOR]

Low-temperature-phase (LTP) MnBi thin films with perpendicular magnetization were fabricated. The influence of oxidation on magnetic properties was investigated for samples experiencing the 14-day exposure to air. The saturation magnetization M s of MnBi thin film was reduced by 35% while its coercivity H c was enlarged by 23% due to oxidation. The precipitation of crystalline bismuth was observed in MnBi after exposure to air for 14 days. The reduction of M s is thought to be due to the decomposition of MnBi as a result of the oxidation of Mn, while the enlarged H c is deduced to be caused by the weakened inter-grain exchange energy at grain boundaries. Almost no changes in structural and magnetic properties were observed in the MnBi thin film protected with a Ta capping layer even after prolonged exposure to air. [ABSTRACT FROM AUTHOR]

Abstract: An inverted organic solar cell, consisting of an ultrathin Ca layer for electron transport, the blend of poly(3-hexylthiophene) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 for photon absorption, and a MoO3 layer for hole transport, is optimized. The insertion of MoO3 layer between photoactive layer and Ag anode has been demonstrated to improve both the photocurrent and the fill factor. By optical modeling and experiment, we find that the MoO3 layer also functions as an optical spacer for thin devices. For the optimized device with an active layer thickness of 85nm, Ca thickness of 0.5nm, and MoO3 layer thickness of 5nm, a maximum power conversion efficiency of 3.86% was achieved. [Copyright &y& Elsevier]

Abstract: A series of hot (600 °C) and room temperature C+/Al+ co-implanted 6H–SiC epitaxial films, under different implantation dose levels and high temperature (1550 °C) post-annealing, were studied by a variety of structural and optical characterization techniques, including secondary ion mass spectroscopy, high resolution X-ray diffraction, Fourier transform infrared reflectance, micro-Raman and photoluminescence (PL) spectroscopy. The damage and amorphization of SiC layer by co-implantation, and the elimination/suppression of the implantation induced amorphous layer via high temperature annealing are observed. The recovery of the crystallinity and the activation of the implant acceptors are confirmed. The results from hot or RT co-implantation are compared. [Copyright &y& Elsevier]

Abstract: A filtered cathodic vacuum arc technique has been applied to synthesis iron-nitride thin films on silicon (100) substrate. Two approaches were carried out to introduce the nitrogen gas into the chamber to control the nitrogen content. Films with smooth surface containing α-Fe(N), α′-Fe(N), αʺ-Fe16N2, γ′-Fe4N, ζ-Fe2N, ɛ-Fe3N and γʺ-FeN phases have been obtained, respectively. The magnetic properties of the films show that small amount of nitrogen addition into the iron films increases the saturation magnetization, while excess nitrogen decreases the saturation magnetization. It is explained based on the bond-band-barrier correlation mechanism [C.Q. Sun, Prog. Mater. Sci. 48 (2003) 521] that the electronegative nitrogen changes the valence states of iron into Fe+ or Fe dipoles with higher magnetic momentum compared with an neutral Fe atom in the bulk. [Copyright &y& Elsevier]