Transparent conducting ZnO : Al films on different organic substrates deposited by r.f. sputtering

1. IntroductionThansparellt conducting zinc oxide films have beenextensively studied in recede years, because of theirlow material cost, relatively low deposition temperature and stability in hydrogen plasma compared withITO and SnOZ films[1]. These adVatages are of considerable interest for electrrvoptical conversion device.Compared with undoped ZnO, Al-doped ZnO filmshave lobed resistivity and better stability. nansparellt conducting films deposited on organic substrateshave many lments…     

Transparent and conducting ZnO films prepared by reactive pulsed laser deposition

Undoped ZnO films were prepared on glass substrates without any post-deposition heat treatment using a pulsed Nd:YAG laser ablation of Zn target in the presence of oxygen as reactive atmosphere. Structural, optical, and electrical properties of these films have been investigated as functions of oxygen pressure during deposition. Transparent conducting ZnO films, formed at 120 torr of oxygen pressure, showed an electrical resistivity of 0.27 Ωcm, a mean optical transmittance of 80%, and an optical band gap of 3.25 eV.     

直流磁控溅射法制备掺钛氧化锌透明导电薄膜

采用直流磁控溅射法在室温水冷玻璃衬底上制备出高质量的掺钛氧化锌(ZnO:Ti)透明导电薄膜,研究了溅射功率对ZnO:Ti薄膜结构、形貌和光电性能的影响,结果表明,溅射功率对ZnO:Ti薄膜的结构和电阻率有显著影响.XRD表明,ZnO:Ti薄膜为六角纤锌矿结构的多晶薄膜,且具有c轴择优取向.当溅射功率为130W时,实验制备的ZnO:Ti薄膜的电阻率具有最小值9.67×10~(-5)Ω·cm.实验制备的ZnO:Ti薄膜具有良好的附着性能,可见光区平均透过率超过91%.ZnO:Ti薄膜可以用作薄膜太阳能电池和液晶显示器的透明电极.     

Characterization of ZnO：Al Films Deposited on Organic Substrate by r.f. Magnetron Sputtering

Transparent conducting Al-doped zinc oxide (ZnO:AI) films with good adhesion have been deposited on polyimide thin film substrates by r.f. magnetron sputtering technique at low substrate temperature (25-180℃). The structural, optical and electrical properties of the deposited films were investigated. High quality films with electrical resistivity as low as 8.5×10-4 Ω·cm and the average transmittance over 74% in the wavelength range of the visible spectrum have been obtained. The electron carrier concentrations are in the range from 2.9×1020 to 7.1×1020 cm-3 with mobilities from 4 to 8.8 cm2 V-1s-1. The densities of the films are in the range from 4.58 to 5.16 g/cm-3.     

衬底温度对Sn掺杂ZnO薄膜结构、电学和光学性能的影响

采用射频磁控溅射技术在石英衬底上制备了掺杂浓度为0.5％(原子分数)的ZnO∶Sn(TZO)薄膜,研究了不同衬底温度下薄膜的结构、形貌、电学和光学的性能.研究发现,TZO薄膜沿着C轴择优生长,在400℃时结晶度最好,最低电阻率为2.619×10-2Ω·cm,在可见光范围内具有较好的透光率.     

Ga-Ti共掺杂ZnO透明导电薄膜的微观结构和光电性能研究

采用磁控溅射方法在玻璃基片上制备了Ga-Ti共掺杂ZnO(GTZO)透明导电薄膜,通过XRD、四探针仪和分光光度计测试,研究了氩气压强对GTZO薄膜光电性能和晶体结构的影响。结果表明:所有GTZO薄膜均为(002)择优取向的六角纤锌矿结构,其光电性能和晶体结构与氩气压强密切相关。当氩气压强为0.4Pa时,GTZO薄膜具有最大的晶粒尺寸(85.7nm)、最小的压应力(-0.231GPa)、最高的可见光区平均透射率(86.1%)、最低的电阻率(1.56×10-3Ω·cm)和最大的品质因子(4.28×105Ω-1·cm-1),其光电综合性能最佳。另外,采用光学表征方法计算了薄膜的光学能隙和折射率,并利用有效单振子理论对折射率的色散性质进行了分析,获得了GTZO薄膜的色散参数。     

室温下射频磁控溅射制备ZnO:Al透明导电薄膜及其性能研究

采用射频磁控溅射技术,在室温下,以ZnO:Al2O3(2%Al2O3(质量比))为靶材,在石英玻璃基底上,采用不同工艺条件制备了ZnO:Al(AZO)薄膜。使用扫描电子显微镜观察了薄膜的表面形貌,X射线衍射分析了薄膜的结构,四探针测量仪得到薄膜的表面电阻,轮廓仪测量了薄膜厚度,并计算了电阻率,最后采用分光光度计测量了薄膜的透过率;研究了溅射功率、溅射气压与薄膜厚度对薄膜电阻率及透过率的影响。结果表明:所制备的AZO薄膜具有(002)择优取向,并且发现薄膜厚度对薄膜的光电性能有明显影响,溅射气压和溅射功率对薄膜电学性能有较大影响,但是对薄膜透过率影响不大。当功率为1kW、溅射气压0.052Pa、AZO薄膜厚度为250nm时,其电阻率为8.38×10-4Ω·cm,波长在550nm处透过率为89%,接近基底的本底透过率92%。当薄膜厚度为1125 nm时薄膜的电阻率降至最低(6.16×10-4Ω·cm)。     

直流磁控溅射功率对溅射生长GZO薄膜光电性能的影响

本文采用直流磁控溅射沉积系统在玻璃基底上沉积镓掺杂氧化锌(GZO)薄膜,将溅射功率从120W调整到240W,步长为30W,研究功率变化对GZO薄膜的晶体结构、表面形貌、光学性能和电学性能的影响。结果表明,溅射功率对GZO薄膜电阻率有显著的影响。溅射功率为210W时薄膜呈现最低电阻率为3.31×10~(-4)Ω·cm,可见光波段平均光学透光率接近84%。随着溅射功率的增加,薄膜表面形貌和生长形态发生较大变化,并直接得到具有一定凸凹不平的微结构,GZO薄膜的致密性先增加后降低。     

衬底温度和氧分压对ZnO：Al薄膜性能的影响研究术

以掺杂质量数为2％的Al2O3：ZnO为靶材,用激光脉冲沉积法,通过改变氧压和衬底温度调整薄膜的性能,制备得到相对优质的ZnO：Al薄膜,采用x射线衍射、紫外-可见分光光度计和霍尔效应测试仪等表征其物相、光学和电学性能,最终得到电阻率为1．27×10^-3Ω／cm^-3、平均光透过率超过80％的透明导电薄膜。     

Indium-doped ZnO thin films deposited by the sol–gel technique

Conducting and transparent indium-doped ZnO thin films were deposited on sodocalcic glass substrates by the sol–gel technique. Zinc acetate and indium chloride were used as precursor materials. The electrical resistivity, structure, morphology and optical transmittance of the films were analyzed as a function of the film thickness and the post-deposition annealing treatments in vacuum, oxygen or argon. The obtained films exhibited a (002) preferential growth in all the cases. Surface morphology studies showed that an increase in the films' thickness causes an increase in the grain size. Films with 0.18 μm thickness, prepared under optimal deposition conditions followed by an annealing treatment in vacuum showed electrical resistivity of 1.3 × 10^− 2 Ωcm and optical transmittance higher than 85%. These results make ZnO:In thin films an attractive material for transparent electrodes in thin film solar cells.     

磁控溅射制备镁镓共掺氧化锌透明半导体薄膜及其性能研究

以MgO∶Ga_2O_3∶ZnO(2%∶2%∶96%,质量分数)陶瓷靶作为溅射源,采用磁控溅射技术在石英玻璃衬底上制备了镁镓共掺氧化锌(MGZO)透明半导体薄膜。采用XRD、SEM、霍尔效应仪和分光光度计对MGZO薄膜进行测试表征,研究了溅射压强对MGZO薄膜晶体结构、电学性质和光学性能的影响。结果表明:所有MGZO薄膜均为六角纤锌矿结构并具有(002)择优取向生长特性,溅射压强对薄膜晶体结构和光电性能有明显影响,但几乎不影响其直接光学能隙(3.41~3.44eV)。当溅射压强为3.5Pa时,MGZO薄膜的结晶质量最好、张应力最小(8.29×10-2 GPa)、电阻率最低(1.62×10-3Ω·cm)、可见光区平均透过率最高(87.8%)、品质因数最大(4.76×103Ω~(-1)·cm~(-1)),具有最好的光电综合性能。     

Influence of annealing temperature on the properties of ZnO:Zr films deposited by direct current magnetron sputtering

Transparent conducting zirconium-doped zinc oxide (ZnO:Zr) films were deposited on quartz substrates by direct current (DC) magnetron sputtering at room temperature. The influence of post-annealing temperature on the structural, morphological, electrical and optical properties of ZnO:Zr films were investigated. When annealing temperature increases from room temperature to 573 K, the resistivity decreases obviously due to an improvement of the crystallinity. However, with further increase in annealing temperature, the crystallinity deteriorates leading to an increase in resistivity. The films annealed at the optimum annealing temperature of 573 K in vacuum have the lowest resistivity of 9.8 × 10⁻⁴ Ω cm and a high transmittance of above 92% in the visible range.     

Highly transparent conductive and near-infrared reflective ZnO:Al thin films

Al-doped ZnO (AZO) thin films have been prepared on glass substrates by pulsed laser deposition. The structural, optical, and electrical properties were strongly dependent on the growth temperatures. The lowest resistivity of 4.5 × 10⁻⁴ Ωcm was obtained at an optimized temperature of 350 °C. The AZO films deposited at 350 °C also had the high optical transmittance above 87% in the visible range and the low transmittance (<15% at 1500 nm) and high reflectance (∼50% at 2000 nm) in the near-IR region. The good IR-reflective properties of ZnO:Al films show that they are promising for near-IR reflecting mirrors and heat reflectors.     

Effects of Substrate Temperature on Properties for Transparent Conducting ZnO:A1 Films on Organic Substrate Deposited by r.f. Sputtering

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Influence of Ar/O2 ratio on the properties of transparent conductive ZnO:Ga films prepared by DC reactive magnetron sputtering

Ga-doped zinc oxide (ZnO:Ga) transparent conductive films with highly (002)-preferred orientation were deposited on glass substrates by DC reactive magnetron sputtering method in Ar + O₂ ambience with different Ar/O₂ ratios. The structural, electrical, and optical properties were investigated by X-ray diffraction, Hall measurement, and optical transmission spectroscopy. The resistivity and optical transmittance of the ZnO:Ga thin films are of the order of 10^− 4 Ω cm and over 85%, respectively. The lowest electrical resistivity of the film is found to be about 3.58 × 10^− 4 Ω cm. The influences of Ar/O₂ gas ratios on the resistivity, Hall mobility, and carrier concentration were analyzed.     

Preparation of ZnO:Al thin film on transparent TPT substrate at room temperature by RF magnetron sputtering technique

Aluminum doped ZnO thin films (ZnO:Al) deposited on flexible substrates are suitable to be used as transparent conductive oxide (TCO) thin films in solar cells because of the excellent optical and electrical properties. TPT films are a kind of composite materials and are usually used as encapsulation material of solar panels. In this paper, ZnO:Al film was firstly deposited on transparent TPT substrate by RF magnetron sputtering. The structural, optical, and electrical properties of the film were investigated by X-ray diffractometry (XRD), scanning electron microscope (SEM), UV–visible spectrophotometer, as well as Hall Effect Measurement System. Results revealed that the obtained film had a hexagonal structure and a highly preferred orientation with the c-axis perpendicular to the substrate. Also, the film showed a high optical transmittance over 80% in the visible region and a resistivity of about 3.03 × 10^? 1 Ω·cm.     

Properties of Nb-doped ZnO transparent conductive thin films deposited by rf magnetron sputtering using a high quality ceramic target

Nb-doped ZnO films with (002) orientation have been grown on glass substrates by rf magnetron sputtering followed by vacuum annealing at 400°C for 3 h. The microstructures and surface figures of the Nbdoped ZnO films were investigated with X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. And its optical and electrical properties were measured at room temperature using a four-point probe technique and 756-type spectrophotometer, respectively. X-ray diffraction (XRD) revealed that the films are highly textured along the c axis and perpendicular to the surface of the substrate. After annealing at 400°C for 180 min under vacuum, transmittance of about 90% in visible region for Nb doped ZnO films was confirmed by the optical transmission spectra, and the low resistivity of 5·47 × 10⁻³ Ω·cm was obtained.     

Tungsten-doped ZnO transparent conducting films deposited by direct current magnetron sputtering

Highly conducting and transparent thin films of tungsten-doped ZnO (ZnO:W) were prepared on glass substrates by direct current (DC) magnetron sputtering at low temperature. The effect of film thickness on the structural, electrical and optical properties of ZnO:W films was investigated. All the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. The electrical resistivity first decreases with film thickness, and then increases with further increase in film thickness. The lowest resistivity achieved was 6.97 × 10⁻⁴ Ω cm for a thickness of 332 nm with a Hall mobility of 6.7 cm² V⁻¹ s⁻¹ and a carrier concentration of 1.35 × 10²¹ cm⁻³. However, the average transmittance of the films does not change much with an increase in film thickness, and all the deposited films show a high transmittance of approximately 90% in the visible range.     

The properties of aluminum-doped zinc oxide thin films prepared by rf-magnetron sputtering from nanopowder targets

Aluminum-doped zinc oxide (ZnO:Al) films were deposited onto glass substrates by rf-magnetron sputtering at ambient temperature using, for the first time, doped nanocrystalline powder synthesized by the sol–gel method. The effects of aluminum on structural, electrical, morphological and optical properties were investigated. The films showed a hexagonal wurtzite structure and high preferential orientation in the (002) crystallographic direction. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the films morphology. The obtained samples have a typical columnar structure and a very smooth surface. The optical transmittance spectra showed transmittance higher than 90% within the visible wavelength region. A minimum resistivity of 5.436 · 10^− 5 Ω cm at room temperature was obtained for the 3.0 at.% Al-doped film.     

Deposition of Al-doped ZnO films on polyethylene naphthalate substrate with radio frequency magnetron sputtering

100 nm Al-doped ZnO (AZO) thin films were deposited on polyethylene naphthalate (PEN) substrates with radio frequency magnetron sputtering using 2 wt.% Al-doped ZnO target at various deposition conditions including sputtering power, target to substrate distance, working pressure and substrate temperature. When the sputtering power, target to substrate distance and working pressure were decreased, the resistivity was decreased due to the improvement of crystallinity with larger grain size. As the substrate temperature was increased from 25 to 120 °C, AZO films showed lower electrical resistivity and better optical transmittance due to the significant improvement of the crystallinity. 2 wt.% Al-doped ZnO films deposited on glass and PEN substrates at sputtering power of 25 W, target to substrate distance of 6.8 cm, working pressure of 0.4 Pa and substrate temperature of 120 °C showed the lowest resistivity (5.12 × 10^− 3 Ω cm on PEN substrate, 3.85 × 10^− 3 Ω cm on glass substrate) and high average transmittance (> 90% in both substrates). AZO films deposited on PEN substrate showed similar electrical and optical properties like AZO films deposited on glass substrates.