Influence of Zr(50)Cu(50) thin film metallic glass as buffer layer on the structural and optoelectrical properties of AZO films

Aluminum-doped ZnO(AZO) thin films with thin film metallic glass of Zr(50)Cu(50) as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature on structural, optical, and electrical properties of AZO thin film are investigated. Increasing the thickness of buffer layer and substrate temperature can both promote the transformation of AZO from amorphous to crystalline structure, while they show(100)and(002) unique preferential orientations, respectively. After inserting Zr(50)Cu(50) layer between the glass substrate and AZO film, the sheet resistance and visible transmittance decrease, but the infrared transmittance increases. With substrate temperature increasing from 25℃ to 520℃, the sheet resistance of AZO(100 nm)/Zr(50)Cu(50)(4 nm) film first increases and then decreases, and the infrared transmittance is improved. The AZO(100 nm)/Zr(50)Cu(50)(4 nm) film deposited at a substrate temperature of 360℃ exhibits a low sheet resistance of 26.7 ?/, high transmittance of 82.1% in the visible light region, 81.6% in near-infrared region, and low surface roughness of 0.85 nm, which are useful properties for their potential applications in tandem solar cell and infrared technology.     

粉末靶制备的AZO/Ag/AZO透明导电薄膜的光电性能

室温下,采用射频磁控溅射AZO粉末靶和Ag靶在玻璃基底上制备Ag层厚度分别为12 nm和15 nm两组对称结构掺铝氧化锌/银/掺铝氧化锌(AZO/Ag/AZO)透明导电薄膜,研究了Ag层和AZO层厚度对薄膜光电性能的影响。结果表明:3层薄膜的可见光区平均透光率达到了80%,550 nm处的最高透过率达到了88%,方块电阻小于5 Ω/□。Ag层厚度是影响AZO/Ag/AZO薄膜光电性能的主要因素,AZO层的厚度对薄膜光学性能影响较大。     

射频溅射功率对AZO薄膜结构及光电特性和热稳定性的影响

采用射频磁控溅射法,在玻璃基片上制备了ZnO:Al(AZO)透明导电薄膜。用X射线衍射(XRD)仪、紫外-可见分光光度计、方块电阻测试仪和台阶仪对不同溅射功率下Al掺杂ZnO薄膜的结晶、光学、电学性能、沉积速率以及热稳定性进行了研究。研究结果表明:不同溅射功率下沉积的AZO薄膜具有六角纤锌矿结构,均呈c轴择优取向;(002)衍射峰强和薄膜的结晶度随溅射功率的提高逐渐增强;随溅射功率的提高,AZO薄膜的透射率有所下降,但在可见光(380～780nm)范围内平均透射率仍80%;薄膜的方块电阻随溅射功率的增加逐渐减小;功率为160～200W时,薄膜的热稳定性最好,升温前后方块电阻变化率为13%。     

Study on the electrical and optical properties of Ag/Al-doped ZnO coatings deposited by electron beam evaporation

A layer of silver was deposited onto the surface of glass substrates, coated with AZO (Al-doped ZnO), to form Ag/AZO film structures, using e-beam evaporation techniques. The electrical and optical properties of AZO, Ag and Ag/AZO film structures were studied. The deposition of Ag layer on the surface of AZO films resulted in lowering the effective electrical resistivity with a slight reduction of their optical transmittance. Ag (11 nm)/AZO (25 nm) film structure, with an accuracy of ±0.5 nm for the thickness shows a sheet resistance as low as 5.6 ± 0.5 Ω/sq and a transmittance of about 66 ± 2%. A coating consisting of AZO (25 nm)/Ag (11 nm)/AZO (25 nm) trilayer structure, exhibits a resistance of 7.7 ± 0.5 Ω/sq and a high transmittance of 85 ± 2%. The coatings have satisfactory properties of low resistance, high transmittance and highest figure of merit for application in optoelectronics devices including flat displays, thin films transistors and solar cells as transparent conductive electrodes.     

Transparent conductive and near-infrared reflective Cu-based Al-doped ZnO multilayer films grown by magnetron sputtering at room temperature

Cu-based Al-doped ZnO multilayer films were deposited on glass substrates by DC magnetron sputtering at room temperature. Three kinds of multilayer structures (AZO/Cu, AZO/Cu/AZO, and Cu/AZO) were designed for comparison, and the effects of the Cu layer thickness on photoelectrical properties of the multilayer films were investigated. The results revealed that the transparent-conductive property and near-infrared reflectance of the films are closely correlated with the Cu layer thickness, and among the three structures, AZO/Cu bi-layer films exhibited preferable photoelectrical properties. The AZO/Cu bi-layer film with a Cu layer thickness of 7 nm displayed the highest figure of merit of 4.82 × 10⁻³ Ω⁻¹, with a low sheet resistance of 21.7 Ω/sq and an acceptable visible transmittance of 80%. The near infrared reflectance above 50% can be simultaneously obtained. The good performance of the coatings indicates that they are promising for coated glasses, thin film solar cells and heat-reflectors.     

退火对ZnO:Al薄膜光致发光性能的影响

 采用溶胶-凝胶工艺在石英衬底上制备ZnO:Al（AZO）薄膜，通过不同温度的退火处理，研究了退火对AZO薄膜结构和光致发光特性的影响。XRD图谱表明：所制备的薄膜具有c轴高度择优取向，随着退火温度的升高，(002)峰的强度逐渐增强，同时(002)峰的半高宽逐渐减小,表明晶粒在不断增大。未退火样品的光致发光（PL）谱由361 nm附近的紫外带边发射峰和500 nm附近的深能级发射峰组成。样品经退火后，以500 nm为中心的绿带发射逐渐减弱，而带边发射强度有所增强,并且逐渐红移到366 nm附近，与吸收边移动的测试结果相吻合。对经过不同时间退火的样品分析表明，AZO薄膜的发光特性与退火时间也有很大关系，时间过短可见波段的发射较强，但时间过长会使晶粒发生团聚，导致紫外发射峰强度减弱。     

用粉末靶在玻璃和PI衬底上制备AZO/Ag/AZO薄膜

室温下在玻璃和聚酰亚胺两种不同衬底上, 采用射频磁控溅射法溅射掺铝氧化锌(AZO)粉末靶和固体Ag靶, 制备了两组AZO/Ag/AZO 3层透明导电薄膜, 研究了AZO层厚度对不同衬底3层膜结构和光电性能的影响.结果表明:不同衬底的两组AZO/Ag/AZO薄膜均为多晶膜.当Ag层厚度不变时, 随着AZO层厚度的增加, 两组薄膜电学性能变化不大, 透射峰向长波方向移动.玻璃和PI衬底上制备的AZO(30 nm)/Ag(14 nm)/AZO(30 nm)薄膜, 在550 nm处的透光率分别为85%和70%, 方块电阻分别为2.6 Ω/□和4.6 Ω/□.     

Effects of substrate temperature on the efficiency of hydrogen incorporation on the properties of Al-doped ZnO films

Al-doped ZnO (AZO) transparent conducting films were successfully prepared on glass substrates by RF magnetron sputtering at different substrate temperatures in Ar and H₂ + Ar sputtering ambient. The effects of substrate temperature on the effectiveness of hydrogen incorporation in Al-doped ZnO films were investigated. The microstructural, electrical and optical properties of AZO films were systematically analyzed by surface profiler, X-ray diffractometry, scanning electron microscope, four-point probe measurement and UV/vis spectrophotometer. The XRD patterns and SEM pictures indicate that the crystallinity of AZO thin films was markedly improved with hydrogen incorporation at low substrate temperature, while the improvement of crystallinity was not an obvious change at high substrate temperature. The results also indicate that hydrogen incorporation has the stronger effectiveness on the transparent conductive properties of AZO films with the substrate temperature decreasing. The resistivity of the films decreases, especially for lower substrate temperatures, due to the incorporation of hydrogen atoms. These results suggest that substrate temperature should be controlled to the lower level to effectively reduce resistivity without detriment to transmittance of AZO thin films when hydrogen is incorporated.     

外加磁场对射频磁控溅射制备铝掺杂氧化锌薄膜影响的研究

利用射频磁控溅射法制备了铝掺杂氧化锌(AZO)透明导电薄膜,在传统的磁控溅射系统中引入外加磁场,研究了外加磁场对AZO薄膜沉积速率、形貌结构及光电特性的影响.研究结果表明,外加磁场后薄膜的沉积速率从不加磁场的13.04 nm/min提高到了19.93 nm/min;外加磁场后薄膜表面平整致密、颗粒大小均匀,结晶质量较高,而不加磁场薄膜表面形貌呈蠕虫状,薄膜质量较差.溅射时间为90 min时,外加磁场前后AZO薄膜方阻分别为30.74?/和12.88?/.外加磁场对薄膜可见光透过率影响不大,但使薄膜的吸收边蓝移现象更明显.运用ansys软件对磁控溅射二维磁场分布模拟后发现,外加磁场提高了靶上方横向磁场强度,改善了磁场分布的均匀性,加强了磁场对电子的磁控作用,提高了靶电流,是AZO薄膜的溅射速率、光电性能和形貌结构得到提高和优化的原因.     

生长条件对脉冲激光沉积制备ZnO：Al薄膜光电性能的影响

本文研究了脉冲激光沉积(PLD)生长过程中, 铝掺量、氧压及衬底温度等实验参数对ZnO:Al(AZO)薄膜生长的影响, 并利用扫描电子显微镜、原子力显微镜、X射线衍射、霍尔效应、光透射光谱等实验手段对其透明导电性能进行了探讨. 变温霍尔效应和光透射测量表明, 当靶材中铝掺量大于0.5 wt%时, 所制备AZO薄膜中铝施主在80 K时已完全电离, 因Bernstein-Moss (BM) 效应其带隙变大, 均为重掺杂简并半导体. 进一步系统研究了氧压和衬底温度对AZO薄膜透明导电性能的影响, 实验发现当氧压为1 Pa, 衬底温度为200 ℃时, AZO 导电性能最好, 其霍尔迁移率为28.8 cm²/V·s, 薄膜电阻率最小可达2.7×10^-4 Ω·cm, 且在可见光范围内光透过率超过了85%. 氧压和温度的增加, 都会导致薄膜电阻率变大. 关键词： 脉冲激光沉积法 ZnO：Al薄膜 透光性 导电性     

Optimization of the optical and electrical properties of electron beam evaporated aluminum-doped zinc oxide films for opto-electronic applications

Aluminum-doped zinc oxide (AZO) thin films have been deposited by electron beam evaporation technique on glass substrates. The structural, electrical and optical properties of AZO films have been investigated as a function of annealing temperature. It was observed that the optical properties such as transmittance, reflectance, optical band gap and refractive index of AZO films were strongly affected by annealing temperature. The transmittance values of 84% in the visible region and 97% in the NIR region were obtained for AZO film annealed at 475 °C. The room temperature electrical resistivity of 4.6×10⁻³ Ω cm has been obtained at the same temperature of annealing. It was found that the calculated refractive index has been affected by the packing density of the thin films, whereas, the high annealing temperature gave rise to improve the homogeneity of the films. The single-oscillator model was used to analyze the optical parameters such as the oscillator and dispersion energies.     

不同衬底和CdCl2退火对磁控溅射CdS薄膜性能的影响

在科宁7059玻璃, FTO, ITO, AZO四种衬底上磁控溅射CdS薄膜, 并在CdCl₂+干燥空气380 ℃退火, 分别研究了不同衬底和退火工艺对CdS薄膜形貌、结构和光学性能的影响. 扫描电子显微镜形貌表明: 不同衬底原位溅射CdS薄膜的形貌不同, 退火后相应CdS薄膜的晶粒度和表面粗糙度明显增大. XRD衍射图谱表明: 不同衬底原位溅射和退火CdS薄膜均为六角相和立方相的混相结构, 退火前后科宁7059玻璃, FTO, AZO衬底上CdS薄膜有 H(002)/C(111) 最强衍射峰, ITO衬底原位溅射CdS薄膜没有明显的最强衍射峰, 退火后出现 H(002)/(111) 最强衍射峰. 紫外-可见分光光度计分析表明: AZO, FTO, ITO, 科宁7059玻璃衬底CdS薄膜的可见光平均透过率依次减小, 退火后相应衬底CdS薄膜的可见光平均透过率增大, 光学吸收系数降低; 退火显著增大了不同衬底CdS薄膜的光学带隙. 分析得出: 上述结果是由于不同衬底类型和退火工艺对CdS多晶薄膜的形貌、结构和带尾态掺杂浓度改变的结果. 关键词： CdS薄膜 磁控溅射 退火再结晶 带尾态     

Recovery of soft magnetic properties of FeNiSm films by Ta interlayer

The magnetic properties of FeNiSm thin films with different thicknesses, different Ta interlayer thicknesses and different numbers of Ta interlayers were investigated. The single layer FeNiSm shows in-plane uniaxial anisotropy at a thickness below critical value, but shows weak perpendicular anisotropy with a stripe domain structure at thickness above the critical value. Experiments indicate that one or more Ta interlayers inserted into thick FeNiSm films with weak perpendicular anisotropy were effective not only in canceling the perpendicular anisotropy, but also in recovering the in-plane uniaxial anisotropy. Blocking of the columnar growth of FeNi grains by the Ta interlayer is considered to be responsible for this spin reorientation phenomenon. Moreover, the magnetization reversal mechanism in FeNiSm films with uniaxial anisotropy can be ascribed to coherent rotation when the applied field is close to the hard axis and to domain-wall unpinning when the applied field is close to the easy axis. The dynamic magnetic properties of FeNiSm films with uniaxial anisotropy were investigated in the frequency range 0.1-5 GHz. The degradation of the soft magnetic properties of magnetic thin films due to the growth of columnar grains can be avoided by insertion of a Ta interlayer.     

Effect of Alumina and Chromium Interlayers on Microstructures and Optical Properties of Thin Ag Films on Glass Substrates

Effects of alumina and chromium interlayers on the microstructure and optical properties of thin Ag films are investigated by using spectrophotometry, x-ray diffraction and AFM. The characteristics of Ag films in Ag/glass, Ag/l2O3/glass and Ag/Cr/glass stacks are analysed. The results indicate that the insertion of an Al2O3 or Cr layer decreases the grains and influences the reflectance of Ag films. The reflectance of the Ag film can be increased by controlling the thickness of alumina interlayer. The stability of Ag films is improved and the adhesion of Ag films on glass substrates is enhanced by alumina as an interlayer.     

The transparence comparison of Ga- and Al-doped ZnO thin films

The Ga-doped ZnO (GZO) and Al-doped ZnO (AZO) thin films were grown on quartz glass substrates by pulsed laser deposition under different oxygen partial pressures (PO₂). The transparent performances of films versus properties of structure and conductivity were discussed. With the increase of PO₂, the transmittance of both GZO films and AZO films increased to maximum and then decreased which were in according with the change of crystallization quality. The transmittance of GZO films was higher than that of AZO films, which were not dominated by the impurity ions induced by doping. AFM images and surface roughness mean square coefficients showed that the surfaces of GZO films were smoother than that of AZO films, which were due to the dopant Ga acting as the surfactant and smoothed the GZO films surface.     

Nanoindentation measurements on modified diamond-like carbon thin films

In the present study, we explored the effect of metallic interlayers (Cu and Ti) and indentation loads (5-20 mN) on the mechanical properties of plasma produced diamond-like carbon (DLC) thin films. Also a comparison has been made for mechanical properties of these films with pure DLC and nitrogen incorporated DLC films. Introduction of N in DLC led to a drastic decrease in residual stress (S) from 1.8 to 0.7 GPa, but with expenses of hardness (H) and other mechanical properties. In contrast, addition of Cu and Ti interlayers between substrate Si and DLC, results in significant decrease in S with little enhancement of hardness and other mechanical properties. Among various DLC films, maximum hardness 30.8 GPa is observed in Ti-DLC film. Besides hardness and elastic modulus, various other mechanical parameters have also been estimated using load versus displacement curves.     

Thickness dependence of structural, electrical and optical properties of indium tin oxide (ITO) films deposited on PET substrates

Without intentionally heating the substrates, indium tin oxide (ITO) thin films of thicknesses from 72 nm to 447 nm were prepared on polyethylene terephthalate (PET) substrates by DC reactively magnetron sputtering with pre-deposition substrate surfaces plasma cleaning. The dependence of structural, electrical, and optical properties on the films thickness were systematically investigated. It was found that the crystal grain size increases, while the transmittance, the resistivity, and the sheet resistance decreases as the film thickness was increasing. The thickest film (∼447 nm) was found of the lowest sheet resistance 12.6 Ω/square, and its average optical transmittance (400-800 nm) and the 550 nm transmittance was 85.2% and 90.4%, respectively. The results indicate clearly that dependence of the structural, electrical, and optical properties of the films on the film thickness reflected the improvement of the film crystallinity with the film thickness.     

铜铟镓硒薄膜太阳能电池新型图形化透明前电极研究

为了优化铜铟镓硒薄膜太阳能电池的前电极,提高铜铟镓硒薄膜太阳能电池的效率,提出了一种可应用于铜铟镓硒薄膜太阳能电池的AZO/图案化Ag薄膜/AZO结构的前电极,中间层的Ag薄膜与电池顶层的金属栅线具有完全相同的图案和尺寸,并且位于金属栅线的正下方,这种新型结构可以提高电池前电极的电学性能,但对电池来说不会带来额外的光学损失。对比了新型前电极结构与几种传统前电极的电学和光学性能,并且制备了相应的电池进行了性能对比。实验结果表明,新型的前电极结构可以提高铜铟镓硒薄膜太阳能电池的短路电流,相对传统AZO电极,电池效率从13. 83%提高到14. 53%。本结构可以明显提高电池效率。     

热处理温度对ZnO∶Al薄膜性能的影响

利用溶胶-凝胶技术在玻璃衬底上制备了ZnO∶Al薄膜,表征了薄膜的结构、光透过和光致发光特性,探讨了热处理温度对薄膜晶体结构和光学性质的影响.结果表明,在热分解温度400 ℃和退火温度600 ℃时,ZnO∶Al薄膜的C轴择优取向明显,透过率较高.在热处理温度400 ℃情况下,激发波长340 nm的光致发光谱中有三个发光中心,紫外发光强度随退火温度的升高先升高后下降,500 ℃时发光强度最强.其它两个发光峰的强度随退火温度的升高而降低甚至消失.激发波长不同,ZnO∶Al薄膜的发光中心和强度均发生变化.     

Deposition of quasi-crystal Al-doped ZnO thin films for photovoltaic device applications

Quasi-crystal aluminum-doped zinc oxide (AZO) films were prepared by in situ radio frequency (RF) magnetron sputtering (sputtering without annealing) on glass substrates. The influence of deposition parameters on the optoelectronic and structural properties of the in situ deposited quasi-crystal AZO films was investigated in order to compare resulting samples. X-ray diffraction (XRD) patterns show that the quasi-crystal AZO thin films have excellent crystallization improved with increase of the RF power and substrate temperature, with an extremely preferential c-axis orientation exhibit sharp and narrow XRD pattern similar to that of single-crystal. Field emission scanning electron microscopy (FESEM) images show that quasi-crystal AZO thin films have uniform grains and the grain size increase with the increase of RF power and substrate temperature. Craters of irregular size with the columnar structure are observed in the quasi-crystal AZO thin films at a lower substrate temperature while many spherical shaped grains appeared at a higher substrate temperature. The average optical transmittance of all the quasi-crystal AZO films was over 85% in the 400-800 nm wavelength range. The resistivity of 4.176 × 10⁻⁴ Ω cm with the grain size of 76.4891 nm was obtained in the quasi-crystal AZO thin film deposited at 300 °C, under sputtering power of 140 W.