Low-temperature conformal vacuum deposition of OLED devices using close-space sublimation

Close-space sublimation(CSS)has been demonstrated as an alternative vacuum deposition technique for fabricating organic light-emitting diodes(OLEDs).CSS utilizes a planar donor plate pre-coated with organic thin films as an area source to rapidly transfer the donor film to a device substrate at temperatures below 200℃.CSS is also conformal and capable of depositing on odd-shaped substrates using flexible donor media.The evaporation behaviors of organic donor films under CSS were fully characterized using model OLED materials and CSS-deposited films exhibited comparable device performances in an OLED stack to films deposited by conventional point sources.The low temperature and conformal nature of CSS,along with its high material utilization and short process time,make it a promising method for fabricating flexible OLED displays.

STUDY ON DIAMOND LIKE CARBON THIN FILM BY FILTERED VACUUM ARC DEPOSITION

Diamond like carbon thin film is successfully deposited on silicon, titanium and stainless steel substrate at low temperature in a filtered vacuum arc deposition system. Arc discharges are established on a graphite cathode in the system with a toroidal macroparticle filter. A cathode activating magnetic field and a filtered magnetic field to collimate the plasma beam are applied. Ion current convected by the plasma beam is measured with a negatively biased probe. It is shown that the magnetic field of the coils located on the plasma duct has a strong influence on cathode spot behavior. Orthogonally the designed experiments are carried out to optimize the deposition parameters of arc stability. Finally, the diamond like carbon thin films are studied by scanning electron microscope (SEM) and Raman spectrum.

Optical and electrical properties of BaSnO_(3) and In_2O_(3) mixed transparent conductive films deposited by filtered cathodic vacuum arc technique at room temperature

For the crystalline temperature of BaSnO_(3)(BTO)was above 650℃,the transparent conductive BTO-based films were always deposited above this temperature on epitaxy substrates by pulsed laser deposition or molecular beam epitaxy till now which limited there application in low temperature device process.In the article,the microstructure,optical and electrical of BTO and In_(2)O_(3) mixed transparent conductive BaInSnO_(x)(BITO)film deposited by filtered cathodic vacuum arc technique(FCVA)on glass substrate at room temperature were firstly reported.The BITO film with thickness of 300 nm had mainly In_(2)O_(3) polycrystalline phase,and minor polycrystalline BTO phase with(001),(011),(111),(002),(222)crystal faces which were first deposited at room temperature on amorphous glass.The transmittance was 70%–80%in the visible light region with linear refractive index of 1.94 and extinction coefficient of 0.004 at 550-nm wavelength.The basic optical properties included the real and imaginary parts,high frequency dielectric constants,the absorption coefficient,the Urbach energy,the indirect and direct band gaps,the oscillator and dispersion energies,the static refractive index and dielectric constant,the average oscillator wavelength,oscillator length strength,the linear and the third-order nonlinear optical susceptibilities,and the nonlinear refractive index were all calculated.The film was the n-type conductor with sheet resistance of 704.7Ω/□,resistivity of 0.02Ω⋅cm,mobility of 18.9 cm2/V⋅s,and carrier electron concentration of 1.6×10^(19) cm^(−3) at room temperature.The results suggested that the BITO film deposited by FCVA had potential application in transparent conductive films-based low temperature device process.

Experimental Research of DLC Film Deposited by Filtered Vacuum Arc Evaporation

Diamond like carbon (DLC) films was grown successfully on silicon, titanium and high speed steel (HSS) substrate at low temperature in a filtered vacuum arc deposition system. Arc discharges were established on a graphite cathode in this home built system with a toridal macroparticles filter. Ion current convected by the plasma beam was measured with a negatively biased probe. It was shown that the magnetic field of the coils located on the plasma duct has a strong influence on ion current. Scanning electron microscope (SEM), atomic force microscope (AFM) and Raman spectrum are used to study the DLC films. Tribological behaviors of the deposited film are also studied.

Effect of pulsed bias on the properties of ZrN/TiZrN films deposited by a cathodic vacuum arc

ZrN/TiZrN multilayers are deposited by using the cathodic vacuum arc method with different substrate bias（from 0 to 800 V）,using Ti and Zr plasma flows in residual N 2 atmosphere,combined with ion bombardment of sample surfaces.The effect of pulsed bias on the structure and properties of films is investigated.Microstructure of the coating is analyzed by X-ray diffraction（XRD）,and scanning electron microscopy（SEM）.In addition,nanohardness,Young＇s modulus,and scratch tests are performed.The experimental results show that the films exhibit a nanoscale multilayer structure consisting of TiZrN and ZrN phases.Solid solutions are formed for component TiZrN films.The dominant preferred orientation of TiZrN films is（111） and（220）.At a pulsed bias of 200 V,the nanohardness and the adhesion strength of the ZrN/TiZrN multilayer reach a maximum of 38 GPa,and 78 N,respectively.The ZrN/TiZrN multilayer demonstrates an enhanced nanohardness compared with binary TiN and ZrN films deposited under equivalent conditions.

In-situ growth of a CdS window layer by vacuum thermal evaporation for CIGS thin film solar cell applications

Highly crystalline and transparent CdS films are grown by utilizing the vacuum thermal evaporation （VTE） method. The structural, surface morphological, and optical properties of the films are studied and compared with those prepared by chemical bath deposition （CBD）. It is found that the films deposited at a high substrate temperature （200 ℃） have a preferential orientation along （002） which is consistent with CBD-grown films. Absorption spectra reveal that the films are highly transparent and the optical band gap values are found to be in a range of 2.44 eV-2.56 eV. Culnl_xGaxSe2 （CIGS） solar cells with in-situ VTE-grown CdS films exhibit higher values of Voc together with smaller values of Jsc than those from CBD. Eventually the conversion efficiency and fill factor become slightly better than those from the CBD method. Our work suggests that the in-situ thermal evaporation method can be a competitive alternative to the CBD method, particularly in the physical- and vacuum-based CIGS technology.

Characterization of the ZnO thin film prepared by single source chemical vapor deposition under low vacuum condition

A novel technique is developed for growing high quality ZnO thin films by means of single source chemical vapor deposition (SS CVD) under low vacuum conditions with the precursor of zinc carbamate Zn4O(CO2Net2)6. SEM, AFM and XRD studies show that the resultant thin films have high density, smooth surface, uniform polycrystalline structure and excellent c-axis orientation. XPS investigation indicates that the ZnO films are free of decomposed precursor residues in the bulk. Careful quantitative XPS analysis reveals that the ZnO films are stoichiometric with O/Zn atomic ratio very close to that of ZnO single crystal.

STUDY ON COMPOSITION, MICROSTRUCTURE AND HARDNESS OF DLC FILMS BY VCAD

DLC super-hard films have been deposited on the substrates of single crystalline Si, pure Ti and stainless steel 18-8 by a method of vacuum cathode arc deposition (VCAD). The composition, microstructure and micro-hardness of the films have been studied in this paper. The results indicate that hardness of the DLC films is different on the different substrates. Hardness of the films increases with decreasing in surface roughness of the films. The maximum value of micro-hardness belongs to the DLC films deposited under the hydrogen pressure of 0.35Pa and the negative bias of 100V.

Study on optical compound films

Using the compound materials and double e-gun evaporation,the compound optical films have been successfully deposited on K9 glass substrate.The refractive index of optical compund films deposited in diffeent parameters have been measured and theoretical formula for calculation refractive index of compound films have been derived.It is shown that the experimental curve for the variation of refractive index with wavelength in 0.4￣1.4 μm region and the theoretical one agree very well.Using these films,the laser reflecting mirror has been successfully coated.

Optical Absorption of Nano-Composite Thin Films of Au in Teflon

Nano-composite films of Au particles in Teflon were obtained by thermal vacuum deposition. The obtained films were characterized by the different shapes and dimensions of the inclusion particles. Absorption spectra of the films were measured in-situ. A model for the calculation of the optical properties of the nano-composite thin films with an inho-mogeneous distribution of the inclusions along the thickness of the film is proposed. Absorption properties of inclusions were analyzed by considering the local field interaction. The calculated absorption profiles are compared with the experimentally obtained absorption profiles. This comparison gives a possibility to draw conclusions about the concentration, shapes and shape distributions of the inclusion particles. For example, the films obtained by duration deposition are characterized by inclusions having the shape of prolate ellipsoids oriented normally to surface of the film.

真空蒸镀钙钛矿太阳能电池器件工艺研究进展

钙钛矿太阳能电池器件因其优异的材料性能已经取得最高25.7%的光电转换效率。常见的钙钛矿薄膜的制备方法分为溶液法和真空蒸镀法。其中真空蒸镀法凭借其无溶剂化的特点,具有环境污染小、膜层致密性高、生产效率高,以及较为容易实现大面积连续化高通量制备等优点,在钙钛矿太阳能电池器件制备领域具有独特优势。针对真空蒸镀法制备高质量钙钛矿薄膜的技术,对真空蒸镀的基本工作原理及应用于钙钛矿薄膜制备的真空设备系统进行介绍,并以钙钛矿太阳能电池光电转换效率为切入点,介绍基于真空蒸镀技术制备钙钛矿太阳能电池器件及优化其光电转换效率的研究进展。探究真空蒸镀设备改进策略(温控系统和蒸发源设置)、蒸镀工艺条件(投料量、蒸镀距离、蒸镀时间、室体内压力、薄膜退火温度及时间)、基底材料极性对钙钛矿薄膜结晶度和晶粒尺寸的影响因素,为采用真空蒸镀技术制备具有高光电转换效率的钙钛矿太阳能电池器件提供重要的理论基础及研究思路。最后,总结真空蒸镀钙钛矿太阳能电池的工艺流程,从降低生产成本与提高生产效率的角度出发,提出连续化生产钙钛矿太阳能电池的构想,并对其商业化发展方向进行展望。

H_(2)对HfO_(2)衬底上等离子体增强化学气相沉积石墨烯的影响

HfO_(2)薄膜和石墨烯是用于制作石墨烯场效应晶体管的主要材料,而采用PECVD(等离子体增强化学气相沉积法)在HfO_(2)衬底上原位生长石墨烯是极具潜力的一种石墨烯制备方法,这种方法有助于降低石墨烯转移过程对石墨烯质量的影响,从而提高石墨烯场效应晶体管的性能。使用真空电子束蒸镀方法在重掺杂单抛硅片衬底上分别于50、150、250℃下沉积了100 nm厚的HfO_(2)薄膜样品;随后选用最优质量的HfO_(2)薄膜作为生长石墨烯的衬底,采用PECVD方法在温度为600℃、CH4流速为4 sccm的条件下,以不同的H2流速(0、5、10、15、20 sccm)原位生成石墨烯薄膜。结果显示,150℃下蒸镀的HfO_(2)薄膜粗糙度最低,表面最平整,同时也拥有最佳的介电性能。当H2流速为10 sccm时,可获得少层石墨烯薄膜,此时的石墨烯薄膜缺陷最小,表面平整且连续性好。通过对HfO_(2)衬底上石墨烯的生长机理进行分析发现,HfO_(2)衬底的低表面能导致含碳物种难以吸附到衬底上,石墨烯不易生长,但适当的H2参与可以有效降低CH4裂解反应的活化能,促进CH4的裂解,有利于生长出大面积的连续型石墨烯薄膜。

聚对二甲苯在电路板上应用的三防技术探讨

本文描述了聚对二甲苯真空气相沉积涂覆工艺在电路板组件表面防护膜层的制备过程,涂膜试验数据以及膜层性能。实验证明,聚对二甲苯高分子膜层对电路板组件表面具有优异的物理性能、电器性能和三防性能,是当前高可靠性需求电子产品多重防护的最佳选择。

微波ECR等离子体辅助反应蒸发沉积ITO膜

发展了一种新型的微波电子回旋共振等离子体（ＥＣＲ）辅助反应蒸发沉积薄膜的方法，并且使用它成功地在低气压（１０￣（－２）Ｐａ）、低温基片（３０～１００℃）上，不作后处理，直接制备出了附着力强，透光率高于８５％，方阻低于１００Ω／□的ＩＴＯ膜。

脉冲偏压对真空电弧沉积TiN薄膜组织与性能的影响

研究了脉冲偏压对真空电弧沉积TiN薄膜组织与性能的影响。结果表明脉冲偏压幅值在50 0～ 1 70 0V ,脉宽比在 1 2 5～ 2 5的范围内 ,沉积温度低于 2 50℃时膜层组织主要由Ti2 N和TiN相构成 ,随脉冲偏压幅值和脉宽比的增大 ,晶面的择尤沉积由Ti2 N( 2 0 0 )向 ( 0 0 2 )转变 ,柱状晶生长程度减弱。膜层具有较高的显微硬度和耐磨性 ,但在过高的脉冲偏压和脉宽比的沉积条件下 ,膜层的性能有下降的趋势。

蒸发、磁控溅射沉积真空对铀薄膜组成和结构的影响

用 X-光电子能谱仪(XPS)、扫描透射电镜(STEM)分析了蒸发、磁控溅射沉积真空对铀薄膜组成和结构的影响。结果表明,在沉积真空2Pa 下,蒸发、磁控溅射沉积的铀薄膜已完全氧化;在沉积真空2×10^(-1)Pa 下,磁控溅射沉积的铀薄膜由金属铀和二氧化铀组成,薄膜呈微晶或无定形结构。

平口喷嘴的真空射流雾化模拟分析

基于breakup和collision液滴破碎模型采用Fluent和Gambit软件对平口喷嘴的真空射流雾化进行了模拟,研究了环境压力、喷射压力和喷嘴直径等参数对射流雾化结构和液滴索特平均直径(Sauter mean diameter,SMD)的影响。结果表明:①随着环境压力的降低,喷射束宽度减小,射流贯穿距离和SMD增加。当环境压力小于0.01 MPa时,各雾化性能参数的变化幅度减小;②环境压力和喷嘴直径一定,随着喷射压力的增加,喷射束宽度呈先快速后缓慢增加的趋势,而射流贯穿距离近似线性增加,SMD值变化不明显;③喷嘴直径越小,喷射束宽度和射流贯穿距离越大,SMD值越小,射流雾化效果越好,更易制备出光滑致密的聚合物薄膜。

离子束辅助沉积和真空退火对硫化锌薄膜应力的影响

在硅基底上用电子束蒸发方法制备了硫化锌薄膜。通过XRD和薄膜应力测试仪研究了离子束辅助沉积和真空退火对硫化锌薄膜应力的影响规律。结果表明,未采用离子辅助技术制备的硫化锌薄膜为压应力,平均应力值为110.6 MPa,当采用离子束辅助工艺时硫化锌薄膜的压应力增加了62.3MPa。真空退火使硫化锌薄膜的平均应力大约降低了二分之一。硫化锌薄膜的微观结构变化是影响薄膜应力的主要因素。

掺Nd纳米ZnO薄膜特性研究

研究了用真空蒸发法在玻璃衬底上制备稀土掺杂纳米ZnO薄膜结构、导电性及光透射性能。结果显示 ,在 5 0 0℃氧化、热处理稀土元素Nd掺杂后能够明显改善纳米ZnO薄膜的结构特性 ,薄膜的晶粒尺寸随掺杂含量的增加而减小。掺Nd使ZnO薄膜的电性能有所改善但使纳米ZnO薄膜的光透射性有所降低。

电弧离子镀技术及其在硬质薄膜方面的应用

从电弧蒸发源控制技术和大颗粒过滤技术出发,论述了电弧离子镀技术最近的发展成果,并总结了电弧离子镀技术在氮化物、氧化物、非晶碳等薄膜方面的技术应用进展,以期能对我国电弧离子镀技术及其在硬质薄膜方面的应用起到一定的参考作用。