优质氧化锌透明导电膜

报道了采用反应电子束蒸发技术制备优质氧化锌透明导电膜的工艺和结果。典型的结果：电阻率低达２×１０－４Ω．ｃｍ，霍尔电子迁移率为５２ｃｍ２（Ｖｓ）－１，厚４０００×１０－１０ｍ膜的方块电阻为８．９Ω／□，可见光透过率大于９０％。分析了源掺杂、镀膜气氛、衬底温度等参数与膜的电导和透光特性的关系。     

有机衬底SnO2掺Sb透明导电膜的制备

采用射频磁控溅射法在有机的柔性衬底上制备出了SnO2 :Sb透明导电膜 ,讨论了薄膜的结构和光电性质对制备条件的依赖关系。制备的样品为多晶薄膜 ,并且保持了二氧化锡的金红石结构。对衬底适当的加热 ,当衬底温度为2 0 0℃时 ,在PI(Polyisocyanate聚酰亚胺 )胶片上制备出了性能良好的薄膜 ,薄膜相应的自由载流子霍耳迁移率有最大值为 13cm2 /VS ,载流子浓度为 15 .5× 10 19cm-3 ,薄膜的电阻率有最小值 3.7× 10 -3 Ω·cm。在可见光范围内 ,样品的相对透过率为 85 %左右     

非晶硅太阳电池织构透明导电膜分析

对一些国外的织构SnO_2膜进行了方块电阻和透过率测量,用扫描电镜观察了表面织构状态,进行了x-射线衍射分析,估算了晶粒大小。对于膜的结构和性能的关系做了扼要讨论,并指出了研究方向。     

低温沉积氧化锌薄膜电学特性

利用金属有机物化学气相沉积系统在玻璃衬底上沉积氧化锌薄膜,在约160℃的低温生长条件下,通过改变n型掺杂气体硼烷的流量来调制薄膜电阻率和光学透过率.基于Hall效应测试分析,研究了掺杂剂硼烷流速对氧化锌薄膜电阻率,载流子浓度,Hall迁移率以及光学透过率的影响,此外还研究了薄膜电学特征参量随薄膜厚度的变化规律.经过一系列优化实验,在玻璃衬底上能够获得低温生长的氧化锌薄膜电阻率约2×10~(-3)Ω·cm,光学透过率的截止波长发生蓝移,从380nm延伸到近340nm.     

室温溅射制备氧化锌铝薄膜及电性能研究

采用直流磁控溅射工艺,室温下在载玻片上制备了氧化锌铝透明导电薄膜.研究了溅射功率和氩气压强对薄膜微观结构和电性能的影响.研究表明:溅射功率和氩气压强通过改变晶粒尺寸和晶界所产生的散射作用而影响薄膜的导电性能.溅射功率低于100W时,薄膜的电阻率随功率增加而明显降低,但超过100W后,薄膜的电阻率下降趋缓,并最终趋于平稳;氩气压强在0.6～3.0Pa范围内增大时,薄膜的电阻率先缓慢减小后逐步增大,当氩气压强为1.5Pa时可获得1.4×103Ω·cm的最小电阻率.     

射频磁控溅射制备的柔性衬底ZnO:Al透明导电薄膜的研究

用射频磁控溅射方法在有机柔性衬底上制备出附着性好、电阻率、透射率高的ＺｎＯ：Ａｌ透明导电膜。研究了薄膜的结构、电学和光学特性。     

纳米Cu夹层ZnO透明导电膜

用射频磁控溅射ZnO陶瓷靶、直流磁控溅射Cu靶的方法在不同基底温度下制备了Cu纳米夹层结构ZnO透明导电膜。用X射线衍射仪、紫外-可见分光光度计、四探针电阻测量仪和原子力显微镜等测试手段对薄膜样品进行表征。室温制备的Cu夹层ZnO薄膜,随着Cu层厚度的增加,ZnO层结晶性变差,可见光区域光学透过率减小,透射曲线蓝移,电阻率先迅速下降后缓慢下降。基底温度对薄膜表面形貌和粗糙度影响显著,随着基底温度的增加,薄膜在可见光区域光学透过率增加,电阻率随基底温度增加而增加。     

Deposition of transparent and conductive Al-doped ZnO thin films for photovoltaic solar cells

The effect of the substrate temperature on the optoelectronic properties of ZnO-based thin films prepared by rf magnetron sputtering has been studied. Three different targets (Zn/Al 98/2 at%, ZnO:Al 98/2 at% and ZnO:Al₂O₃ 98/2 wt%) have been investigated in order to compare resulting samples and try to reduce the substrate temperature down to room temperature. From the ZnO:Al₂O₃ target, transparent conductive zinc oxide has been obtained at 25°C with the average optical transmission in the 400–800 nm wavelength range, T = 80–90% and resistivity, = 3−5 × 10⁻³ Ωcm. In Al:Zn0 layers, the spatial distribution of the electrical properties across the substrate placed parallel to the target has been improved by depositing at high substrate temperatures, above 200°C. Besides, owing to diffusion processes of CuInSe₂ and CdS take place at 200°C, an AI:ZnO/CdS/CuInSe₂ polycrystalline solar cell made with the Al:ZnO deposited at 25°C as the transparent conductive oxide, has shown a more efficient photovoltaic response, η = 6.8%, than the one measured when the aluminium-doped zinc oxide has been prepared at 200°C, η = 1.8%.     

Photo atomic layer deposition of transparent conductive ZnO films

Low-resistivity ZnO films were grown by photo atomic layer deposition (photo-ALD) technique using diethylzinc (DEZ) and H₂O as reactant gases. Self-limiting growth was achieved for the temperature range from 105°C to 235°C. It was found that UV light irradiation was very effective to increase the electron concentration of the films and the electron concentration of 5 × 10²⁰ cm⁻³ was achieved even in undoped ZnO. Thus, the resistivity of the films grown with UV irradiation was one order of magnitude less than that grown without UV irradiation. The minimum resistivity of 6.9 × 10⁻⁴Ω cm was obtained by photo- ALD method without any intentional doping.     

Si doped ZnO thin films for transparent conducting oxides

Abstract

Transparent conductive silicon doped zinc oxide (SZO, 3%Si) thin films are grown by direct current magnetron sputtering on glass substrates at room temperature. Experimental results show that the sputtering time has a significance impact on the growth rate, crystal quality and electrical properties of the films, and have little impact on the optical properties of the films. The growth rate decreases with the sputtering time. The resistivity of ZnO/Si films decreases as the sputtering time increases from 8 to 20 min. However, as the sputtering time increases further, the electrical resistivity increases instead. When other sputtering conditions are kept unchanged, it is found that the optimum sputtering time is 20 min and the achieved lowest resistivity is 4·92×10^?4 Ω cm (sheet resistance?=?11·5 Ω/sq for thickness 427·5 nm). The UV-vis transmission spectrum shows that all film samples present a transmission of above 90·0% in the visible range.     

Low temperature Si doped ZnO thin films for transparent conducting oxides

Si doped zinc oxide (SZO, Si 3%) thin films are grown at low substrate temperature (T≤150 °C) under oxygen atmosphere, using pulsed laser deposition (PLD). Si addition leads to film amorphization and higher densification. Hall effect measurements indicate a resistivity of 7.9×10⁻⁴ Ω cm for SZO thin films deposited at 100 °C under optimized 1.0 Pa oxygen pressure. This value is in good agreement with optical resistivity simulated from the transmittance spectra. XPS measurements suggest more than one oxygen environment, and a Si oxidation state lying in between 2 and 3 only. As a matter of fact, the values of both measured and simulated carrier numbers are smaller than the ones expected, assuming that all Si cations in the ZnO matrix are at the 4⁺ oxidation state. Finally, the differences in the electrical and optical properties of SZO thin films deposited both on glass and PET substrates confirm the strong dependency of the electronic properties to the film crystallinity and stoichiometry in relationship with the substrate nature.     

Preparation of conducting and transparent indium-doped ZnO thin films by chemical spray

Transparent conducting indium-doped zinc oxide thin films were prepared on soda-lime glass substrates by the spray pyrolysis technique. The dependence of the electrical, structural, morphological and optical properties on the preparation conditions has been studied. Two main variables, substrate temperature and molar concentration, were varied in the ranges of 425–525 °C and 0.05–0.5 M, respectively, in order to obtain films with low electrical resistivity and high optical transparency in the visible region. A minimum resistivity value around of 3×10⁻³ Ω cm was obtained for films deposited from highly concentrated starting solutions, 0.4 and 0.5 M. The values of the free-carrier concentration and the electronic mobility were estimated by Hall effect measurements. X-ray diffraction spectra evidenced a preferential orientation along the (1 0 1) direction. The surface morphology was clearly affected with the molar concentration variation, leading to a smoother appearance as the zinc concentration in the starting solution is increased. Typical optical transmittance values in the order of 85% were obtained in all the films.     

Highly transparent and conducting fluorine-doped ZnO thin films prepared by pulsed laser deposition

Highly transparent and conducting fluorine-doped ZnO (FZO) thin films were deposited on glass substrates by pulsed laser deposition. Structural, electrical, and optical properties of the films were investigated as a function of oxygen pressure ranging from 0.01 to 0.5 Pa. All the films had a highly preferential c-axis orientation. The films obtained were dense and very smooth with a typical columnar structure. A minimum resistivity of 4.83×10⁻⁴ Ω cm, with a carrier concentration of 5.43×10²⁰ cm⁻³ and a Hall mobility of 23.8 cm² V⁻¹ s⁻¹, was obtained for FZO film prepared at the optimal oxygen pressure of 0.1 Pa. The average optical transmittance in the entire visible wavelength region was higher than 90%.     

Effect of heat treatment on microstructure and transparent conducting properties of sol-gel ZnO/Al thin films

Abstract

Transparent and conducting Al doped ZnO (AZO) thin films with c axis preferred orientation were prepared on glass substrates via the sol-gel route. The physical and chemical changes of the precursors during thermal treatment were systematically investigated by differential scanning calorimeter and thermogravimetric analysis and the crystallinity of AZO films was characterised by X-ray diffraction. The surface morphology evolution of the films post-heated at 420, 450, 530 and 550°C respectively was observed by SEM. Results reveal that the crystallising process of ZnO/Al comprises two stages: the primary nucleation and growth occurs at 318°C and the continuous crystallisation at 488°C. The optimised preheating and post-heating temperatures are determined at 420 and 530°C respectively. The annealing treatment in vacuum can contribute considerably to the electrical conductivity. The film post-heated at 530°C shows a homogenous dense microstructure and exhibits the minimum sheet resistance of 140 Ω/sq. The visible optical transmittance of all films is more than 90%.     

Low-temperature deposition of transparent ZnO films by the ultrasonic-mediated stepwise method

A novel solution method was developed for the deposition of transparent ZnO film from aqueous solution, integrating the ultrasonic irradiation with the stepwise chemical deposition at relatively high temperature (>100 °C). Obtained ZnO films exhibited high crystallinity, highly preferential orientation along the c-axis, smooth and compact morphology, and high transmittance in the visible band (>80%). The deposition temperature and ultrasonic irradiation were found to have significant influence on the phase purity, crystallinity, grain size, and morphology of ZnO films. While the lower temperature (120 °C) was inefficient to eliminate the intermediate phase of Zn(OH)₂, the higher deposition temperature and ultrasonic irradiation were found powerful to improve the crystalline degree and the quality of film. Mechanism analysis indicated that the rapid water evaporation in the precursor layer and the rapid decomposition of zinc–ammonia complex during the high-temperature deposition process were indispensable for the growth of high-quality ZnO films.     

Gallium-doped ZnO thin films deposited by chemical spray

Gallium-doped zinc oxide (ZnO:Ga) thin films were deposited on glass substrates by the spray pyrolysis technique. The effect of the variation of the [Ga]/[Zn] rate in the starting solution, the substrate temperature as well as the post-annealing treatments on the physical properties was examined. The electrical properties of the films show an improvement with the Ga incorporation and the annealing treatment. All the films were found to be polycrystalline and show a (0 0 2) preferential growth, irrespective of the deposition conditions. The films were of n-type conductivity with an electrical resistivity in the order of 8×10⁻³ Ω cm and optical transmittance higher than 80% in the visible region. These results makes chemically sprayed ZnO:Ga potentially applicable as transparent electrode in photovoltaic devices.