脉冲激光沉积技术制备IrO2薄膜的研究

利用脉冲激光沉积(PLD)技术,在Si(100)衬底上制得了导电氧化铱(IrO2)薄膜.讨论了沉积参数(O2分压、衬底温度)对IrO2薄膜的结构、表面形貌和导电性的影响.结果表明20 Pa为最佳O2分压、400℃～500℃为适宜的沉积温度,此条件下制得的IrO2薄膜结晶完整,组织均匀、形状一致,排列致密,其最低电阻率约为42μΩ·cm.     

脉冲激光沉积类金刚石薄膜涂层研究

利用ＹＡＧ脉冲激光器的３５５ｎｍ和５３２ｎｍ波长制备类金刚石薄膜，采用电极放电法来激发激光等离子体出射簇，发现可较好地提高薄膜的红外透过率；薄膜的红外吸收谱中没有Ｃ－Ｈ吸收带，具有较好的金刚石特性；薄膜可作为红外光学元件和有机小型机械的耐磨涂层。     

脉冲激光沉积技术制备Li2O-V2O5-SiO2薄膜

采用355nm脉冲激光沉积(PLD)技术,以Li6.16V0.61Si0.39O5.36为靶材制备Li2O-V2O5-SiO2薄膜,考察了反应气氛压强、激光能量密度、基片温度等对薄膜结构和性质的影响.结果表明,随着基片温度升高及激光能量密度增大Li2O-V2O5-SiO2薄膜更致密,且室温离子电导率随之增大.在O2压强6.7Pa、激光能量密度12J/cm2和基片温度300℃条件下制备了室温离子电导率为4×10-7S/cm、离子迁移数接近1.O(tion＞99.99%)、厚度均匀、无针孔和裂缝的非晶态Li2O-V2O5-SiO3薄膜.     

ZnO薄膜的脉冲激光沉积及性能研究

利用脉冲激光沉积技术在氧的活性气氛下烧蚀锌靶,在石英玻璃衬底上沉积获得ZnO薄膜,分析并研究了薄膜的微观组织及表面形态及激光能量密度、基体温度、氧压等工艺参数对沉积ZnO膜的影响.结果表明,在基体温度为450～550 ℃、氧压为31 Pa、激光能量密度为31 J/cm2条件下,膜表面完全氧化,ZnO沿(002)晶面生长;当基体温度为500 ℃时,ZnO薄膜光学性能优异.     

不同温度下Ti-Ni薄膜的脉冲激光沉积

形状记忆合金在微电(MEMS)应用日益受到人们重视。TiNi合金由于其优良的大变形、大回复力、耐蚀性和抗疲劳性能，被认为是最有前途的形状记忆合金。TiNi形状记忆(SMA)薄膜通常采用离子溅射法沉积而成，该方法沉积的薄膜除具有SMA功能外，还有与基体块相适应的超弹性。但由于钛属活性元素，沉积过程中力求控制钛的氧化物造成的污染。脉冲激光沉积(PLD)技术是一种简单、可靠、快捷的技术，它减少了TiNi形状记忆合金薄膜形成中的污染，且使沉积薄膜与基材合金成分的匹配良好。新加坡国际大学重点研究了利用PLD技术沉积TiNi膜及不同基…     

功能梯度类金刚石薄膜的脉冲激光制备

长期以来,高质量的纯类金刚石薄膜的成功制备一直受其巨大内部压应力的阻碍,因为这种压力应力导致严重的附着问题。厚度大于５００ｎｍ的类金刚石薄膜中压应力常使薄膜与基体剥离。作者采用功能梯度的设计概念,应用准分子脉冲激光沉积方法,成功制备了厚度超过１．０μｍ的高质量类金刚石薄膜。薄膜中的ＳＰ＾３碳原子含量超过６０％。纳米硬度测试表明,薄膜的弹性模量高达５００ＧＰａ,纳米硬度高达６０ＧＰａ,薄膜与基体间附     

脉冲激光沉积及硒化法制备Cu(In,Ga)Se2薄膜研究

采用脉冲激光沉积和硒化后热处理的方法在石英衬底上制备Cu(In,Ga)Se2（简写为CIGS）薄膜,研究脉冲激光沉积（PLD）技术在制备CIGS薄膜太阳能电池材料上的应用,分析了不同预制层沉积顺序及厚度对CIGS薄膜组织结构、表面形貌、成分以及光学性能的影响。实验结果表明：(1)利用PLD技术及后硒化处理的工艺,制得的CIGS太阳能电池吸收层具有纯相和高结晶度等特性;(2)CuGa/In金属预制层的叠层顺序和叠层数、硒化退火温度对薄膜的结晶质量、晶粒尺寸、成分都具有重要的影响,其中叠层顺序影响最为明显;(3)样品均表现出对可见光区具有透射率低和吸收系数高的光学特性。本工作为制备性能优良的CIGS太阳能电池吸收层,提供了一个新颖的工艺手段。     

功能梯度类金刚石薄膜的脉冲激光制备

长期以来 ,高质量的纯类金刚石薄膜的成功制备一直受其巨大内部压应力的阻碍 ,因为这种压应力导致严重的附着问题。厚度大于 50 0nm的类金刚石薄膜中的压应力常使薄膜与基体剥离。作者采用功能梯度的设计概念 ,应用准分子脉冲激光沉积方法 ,成功制备了厚度超过 1 0 μm的高质量类金刚石薄膜。薄膜中的SP3碳原子含量超过 6 0 %。纳米硬度测试表明 ,薄膜的弹性模量高达 50 0GPa ,纳米硬度高达 6 0GPa ,薄膜与基体间附着良好。证明功能梯度的设计概念可以用于制备较厚的超硬类金刚石薄膜。     

衬底温度对脉冲激光沉积氧化锌薄膜性能的影响

采用脉冲激光沉积(PLD)技术,在Si(100)衬底上制备出高度c轴取向的ZnO薄膜。运用X射线衍射(XRD)、光致发光谱(PL)、拉曼光谱(Raman)对衬底温度在300⁷00℃条件下沉积的氧化锌薄膜进行表征,研究了衬底温度对氧化锌薄膜结构和发光特性的影响。实验表明,700℃条件下沉积的薄膜具有相对较好的结晶质量,其X射线衍射峰半高宽(FWHM)最窄,晶粒最大,近带边紫外发光峰与深能级发光峰的比值显著增强。     

Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates

Layered LiCoO2 (HT-LiCoO2) films were grown on Pt-metalized silicon (PMS) substrates and polished bulk nickel (PBN) substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45 μA·h·cm-2μm-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5C.     

Effect of substrate temperature on structural properties and photocatalytic activity of TiO2 thin films

Titanium dioxide （TiO2） films with anatase structure were prepared on quartz glass substrates by pulse laser ablating titanium （99.99%） target under oxygen pressure of 10 Pa at substrate temperature of 500-800 ℃. The structural properties of the films were characterized by X-ray difffactometry（XRD）, X-ray photoelectron spectroscopy（XPS） and field emission scan electron microscopy（FESEM）. The results show that, as the substrate temperature is increased from 600 ℃ to 800 ℃, the anatase structure of the films changes from random growth to （211）-oriented growth. The absorption edge tested by UV-Vis Spectrometer has a blue shift. The photocatalytic activity of the films was tested on the degradation of methyl orange. It is found that the film with random growth structure exhibits better photo-degradation efficiency than that with （211）-oriented growth structure.     

Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates

Layered LiCoO2 （HT-LiCoO2） films were grown on Pt-metalized silicon （PMS） substrates and polished bulk nickel （PBN） substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100 nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45μA·h·cm^-2·μm^-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5 C.     

退火温度对ZnTe薄膜结构和性能的影响

采用脉冲激光沉积法(PLD)在玻璃衬底上通过室温溅射和原位退火制备了ZnTe薄膜。通过X射线衍射(XRD)、原子力显微镜(AFM)、紫外-可见分光光度计和荧光分光光度计等研究了退火温度对薄膜结构和性能的影响。结果表明:薄膜具有明显的<110>择优生长特征。随着退火温度的升高,薄膜结晶质量逐渐提高,晶粒长大,透过率增加;但过高的退火温度降低了晶体的结晶质量和透过率。当退火温度为280℃时,ZnTe薄膜具有最好的结晶质量,平均透过率达到90%左右。     

Effect of annealing temperature on structure and electrochemical properties of LiCoO2 cathode thin films

LiCoO2 thin films, which can be used as a cathode material in microbatteries, were deposited using radio frequency (r.f.) magnetron sputtering system from a LiCoO2 target and in an O2+Ar atmosphere.The films were characterized by various methods such as XRD, SEM and AFM.The LiCoO2 films were annealed in air at 300, 500, 700 and 800 ℃ respectively.The effect of the annealing temperature on the structure, the surface morphology and the electrochemical properties of the films were investigated.The LiCoO2 thin film deposited at room temperature is amorphous and has smaller grain size.With increasing of annealing temperature, the crystallinity of the films is promoted.When the annealing temperature increases to 700 ℃, the films have a perfect crystalline LiCoO2 phase.The LiCoO2 thin film without annealing has no discharge plateau and small discharge capacity (about 27 μAh·cm-2μm).The discharge capacity increases with the increasing of annealing temperature and reaches 47 μAh·cm-2μm for the film annealed with 700 ℃, which also shows the typical discharge plateau of 3.9 V.The cycle performance of LiCoO2 thin films of as grown and annealed at different temperatures were studied.In the case of the film without thermal treatment, the capacity fading is much faster than that of the film annealed at different temperature, showing about 40% capacity loss only after 25 cycles.However, in the case of the film annealed at 700 ℃, the capacity reaches to steady state gradually and maintained constantly with cycling.After 25 times cycling, the discharge capacity of the film annealed at 700 ℃ decreases to about 36.9 μAh·cm-2·μm, only 0.8% capacity loss per cycle.     

XPS study of BZT thin film deposited on Pt/Ti/SiO2/Si substrate by pulsed laser deposition

Ferroelectric materials were widely applied for actuators and sensors. Barium zirconate titanate Ba（Zr0.25Ti0.75）O3 thin film was grown on Pt/Ti/SiOdSi（100） substrates by pulsed laser deposition. Structure and surface morphology of the thin film were studied by X-ray diffractometry （XRD） and scan electronic microscopy （SEM）. The composition and chemical state near the film surface were obtained by X-ray photoelectron spectroscopy （XPS）. On the sample surface, O 1 s spectra can be assigned to those from the lattice and surface adsorbed oxygen ions, while Cls only result from surface contamination. The result shows that only one chemical state is found for each spectrum of Ba 3d, Zr 3d and Ti 2p photoelectron in the BZT thin film.     

温度对PLD法制备CIGS薄膜性能的影响

利用脉冲激光沉积（PLD）法在40~600 ℃范围内,以石英为基底制备了系列铜铟镓硒（CIGS）薄膜。利用分光光度计,XRD,SEM,EDS等对薄膜进行表征。结果表明,薄膜都以（112）择优取向生长,在40~400 ℃范围内,温度对薄膜结晶质量、晶粒尺寸等影响不明显;温度达到600 ℃时,结晶质量、晶粒尺寸及薄膜的红外透光率等显著增加。认为这主要与Ga元素的扩散受温度的影响有关,温度越高,Ga元素有足够的能量进行充分扩散,并完成晶体结构重组,同时分析了Se元素含量随温度变化的原因。     

Surface morphology and photoluminescence properties of ZnO thin films obtained by PLD

ZnO thin films on Si(111) substrate were deposited by laser ablation of Zn target in oxygen reactive atmosphere, Nd-YAG laser with wavelength of 1 064 nm was used as laser source. XRD and FESEM microscopy were applied to characterize the structure and surface morphology of the deposited ZnO films. The optical properties of the ZnO thin films were characterized by photoluminescence. The UV and deep level (yellow-green) light were observed from the films. The UV light is the intrinsic property and deep level light is attributed to the existence of antisite defects (Ozn). The intensity of UV and deep level light depends strongly on the surface morphology and is explained by the surface roughness of ZnO film. A strongly UV emission can be obtained from ZnO film with surface roughness in nanometer range.     

Influence of preparation methods on photoluminescence properties of ZnO films on quartz glass

The influence of preparation methods on the photoluminescence properties of ZnO film was studied. Two methods were applied to fabricate ZnO films in a conventional pulsed laser deposition apparatus. One is high temperature （500-700℃） oxidation of the metallic zinc film that is obtained by pulsed laser deposition. The other is pulse laser ablation of Zn target in oxygen atmosphere at low temperature （100-250 ℃）. The photoluminescence property was detected by PL spectrum. The room temperature PL spectra of the ZnO films obtained by oxidation method show single violet luminescence emission centered at 424 nm （or 2.90 eV） without any accompanied deep-level emission and UV emission. The violet emission is attributed to interstitial zinc in the films. Nanostructure ZnO film with c-axis （002） orientation is obtained by pulsed laser deposition. The ZnO film deposited at 200 ℃ shows single strong ultraviolet emission. The excellent UV emission is attributed to the good crystalline quality of the film and low intrinsic defects at such low temperature.