真空退火对溅射淀积ZnO：Ga透明导电膜性能的影响

采用射频磁控溅射法在玻璃衬底上低温制备出了镓掺杂氧化锌(ZnO:Ga)透明导电膜,研究了真空退火对薄膜结构、电学和光学特性的影响。结果表明:真空退火后,薄膜结构得到明显改善,电阻率由退火前的1.13×10-3?·cm下降到5.4×10-4?·cm,在可见光区的平均透过率也由未退火前的83%提高到退火后的90%以上。     

沉积温度和退火处理对BCN薄膜结构的影响

采用脉冲激光沉积技术,在Si(100)基片上制备了BCN薄膜,研究了沉积温度和退火处理对BCN薄膜组分和结构的影响。利用傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)对制备的BCN薄膜进行了表征。结果表明:沉积温度升高时,BCN薄膜的组分无明显改变。所制备的BCN薄膜包含B—N,C—B和C—N化学键,是由杂化的B—C—N键构成的化合物。真空退火温度为700℃时,BCN薄膜结构稳定;大气退火温度达到600℃时,BCN薄膜表面发生氧化分解,同时有C≡N键形成,表明C≡N键具有较好的高温热稳定性。     

衬底温度对PLD方法生长Si（111）基ZnO薄膜结晶质量和发光特性的影响

在不同衬底温度下用脉冲激光沉积法（PLD）在n型硅（111）衬底上生长ZnO薄膜.通过对薄膜进行的X射线衍射（XRD）、傅里叶红外吸收（FTIR）、光致发光谱（PL）、透射电子显微镜（TEM）和选区电子衍射（SAED）的测量,研究了衬底温度对PLD方法制备的ZnO薄膜的结晶质量、发光性质以及微观结构的影响.发现在600℃的衬底温度下可以得到结晶质量最佳的ZnO薄膜.随着晶粒直径的减小,出现量子限制效应,在红外吸收和光致发光中的峰位均产生了蓝移.     

磁控溅射制备ZnO缓冲层薄膜的微观结构和光学性能

研究了衬底温度、溅射气压对磁控溅射沉积ZnO缓冲层薄膜的微观结构、表面形貌和光学性能的影响。结果表明,衬底温度、溅射气压对ZnO缓冲层薄膜表面形貌、晶粒尺寸、禁带宽度和光学透过率等有较大影响。综合分析得出最佳的制备ZnO缓冲层薄膜的工艺为250℃、0.6 Pa。在此工艺下制备的ZnO缓冲层薄膜具有很好的ZnO(002)面c轴择优取向,结构致密、尺寸均匀,禁带宽度为3.24 eV,可见光平均透过率为86.93%,符合作CIGS太阳能电池缓冲层的要求。     

射频反应磁控溅射法制备ZnO:Al透明导电薄膜的光电性能

室温下采用射频(RF)反应磁控溅射技术在玻璃衬底上沉积具有(002)择优取向的透明导电Al掺杂ZnO(AZO)薄膜。XRD结果表明,制备的AZO薄膜为多晶,具有c轴择优取向。退火处理能提高其结晶度。在Al靶射频功率为40W,ZnO靶射频功率为250W,氩气流量为15mL/min的条件下,获得200nm厚的薄膜电阻率约3.8×10-3?·cm,在可见光范围内有很好的光透过率。     

室温下反应磁控溅射沉积氧化钛薄膜光学性能和力学性能研究

目的通过对比不同溅射功率和氧气分压下氧化钛薄膜性能的变化规律,分析其力学性能和光学性能的关系。方法在室温条件下,采用直流反应磁控溅射技术在K9玻璃基底上沉积TiO_2薄膜,通过紫外可见红外分光光度计和椭偏仪对薄膜的光学特性进行分析,通过微纳米压痕技术对薄膜的力学性能进行表征。结果在给定工艺参数范围内,薄膜的光学折射率与纳米硬度和弹性模量正相关,随着溅射靶功率的增大,所制备薄膜的折射率、纳米硬度和弹性模量随之增大,而薄膜的光学带隙则随着溅射功率的增大而下降。同时,O_2流量对薄膜的光学性能和力学性能的影响更明显,在较低O_2流量条件下(Q(Ar)/Q(O_2)=10/1),所制备薄膜的折射率减小而光学带隙变大,随着O_2流量进一步减少(Q(Ar)/Q(O2)=20/1),薄膜的折射率增大而光学带隙减小,但薄膜的纳米硬度和弹性模量随O_2流量的减少而下降。结论磁控溅射沉积TiO_2薄膜的折射率与其光学带隙反向相关,而仅在适量氧气条件下所制备的薄膜的力学性能与光学特性有相关性。     

Preliminary Study on Electrical and Optical Properties of ZnO Film Grown by MOCVD

1 ＩｎｔｒｏｄｕｃｔｉｏｎＺｎＯｉｓａｗｉｄｅ ｇａｐ ( 3.2ｅＶａｔｒｏｏｍｔｅｍｐｅｒａｔｕｒｅ)ｓｅｍｉｃｏｎｄｕｃｔｏｒｍａｔｅｒｉａｌｈａｖｉｎｇｔｈｅｗｕｒｔｚｉｔｅｓｔｒｕｃｔｕｒｅｗｉｔｈｄｉｒｅｃｔｅｎｅｒｇｙｂａｎｄ .Ｉｔｈａｓｂｅｅｎｃｏｎｓｉｄｅｒｅｄａｓａｐｒｏｍｉｓ ｉｎｇｍａｔｅｒｉａｌｆｏｒｏｐｔｏｅｌｅｃｔｒｏｎｉｃｄｅｖｉｃｅｓｉｎｔｈｅｎｅａｒｕｌｔｒａｖｉｏｌｅｔ(ＵＶ)ａｎｄｂｌｕｅｓｐｅｃ ｔｒａ .ＡｎｉｎｔｅｒｅｓｔｉｎｇｆｅａｔｕｒｅｏｆＺｎＯｉｓｉｔｓｌ…     

O2浓度对纳米氧化锌形貌、产量和发光性质的影响

目的研究不同O_2体积浓度下,双管管式炉内不同沉积位置处纳米ZnO形貌、产量和发光性质的变化规律。方法采用化学气相沉积法,在双管管式炉的三个不同沉积位置制备了具有不同形貌、产量和性质的纳米ZnO产物。采用扫描电子显微镜(SEM)、X-射线衍射仪(XRD)和荧光分光光度计(PL)等对产物的形貌、结构和光致发光性能进行表征和测试。结果 SEM表明O_2体积浓度较小时,有利于形成针状的多脚结构。O_2体积浓度较大时,有利于生成棒状的多脚状结构。通过对比沉积产物产量发现,当O_2体积浓度较低时,沉积反应主要发生在内管外。随着O_2体积浓度的增大,沉积产物逐渐向内管内部转移,内管口附近的沉积产物增多。XRD结果表明所有产物均为六方纤锌矿结构,当O_2体积浓度为0.0625%时,产物沿c轴择优生长。随着O_2体积浓度的增加,无明显择优取向。PL结果表明,紫外发射峰与绿光发射峰强度的比值随着O_2体积浓度的增加而增大,说明绿光发射峰主要由氧空位引起,随着O_2体积浓度的增加,氧空位逐渐减少。结论通过调节O_2体积浓度可以制备出不同形貌和发光性质的纳米ZnO,从而应用于不同领域,并且在适当的沉积位置可以获得最大产量。     

~(60)Co Gamma Irradiation and Annealing Effects on Transport Properties of Antimony Telluride Platelets Grown by Physical Vapor Deposition

Physical vapor deposition method was employed to deposit antimony telluride(Sb2Te3) crystals in a dual-zone furnace. The microstructure, surface topography and composition of samples were characterized using X-ray diffraction,atomic force and scanning electron microscopy. Seebeck coefficient(S\c), electrical conductivity(r\c) as well as power factor(PF) were enhanced for pure Sb2Te3 samples upon annealing, and the samples annealed at 473 K exhibited the highest PF of 3.16 9 10-3W m-1K-2with an enhancement of 22% in the figure of merit(Z). When the delivered dose of60 Co gamma radiation was increased from 0 to 30 k Gy in the stoichiometric crystals, r\c decreased due to the decrease in mobility. As a result of the increase in S, PF and Z improved by 12.11 and 13.7%, respectively, in the 30 k Gy gammairradiated crystals. Both RH(B||c) and S\c were positive, suggesting that the prepared Sb2Te3 crystals retained the p-type semiconductivity after these treatments.     

Annealing Effects on Structural,Optical Properties and Laser-Induced Damage Threshold of MgF_2 Thin Films

The chemical structures, optical properties and laser-induced damage thresholds of magnesium fluoride films annealed at different temperatures were investigated. The results showed that the stoichiometry of MgF_2 film changed a little with the increase in annealing temperature. Analysis of the optical properties indicated that excellent antireflection behavior of the film in the range of 200–400 nm can be obtained by the samples coated with MgF_2 film. The refractive index increased and the extinction coefficient decreased with increasing annealing temperature. Compared with the asdeposited films, the laser-induced damage threshold was improved after annealing process and decreased with the increase in annealing temperature, which was probably due to the denser film and more absorption centers under higher annealing temperature.     

退火对激光熔覆AlCoCrFeNiTi0.5高熵合金涂层组织和耐磨性的影响

对激光熔覆AlCoCrFeNiTi_0.5高熵合金涂层进行900℃退火,保温5h处理。主要对退火前后样品的微观结构和耐磨性进行研究。XRD结果表明,退火后的AlCoCrFeNiTi_0.5高熵合金涂层,其相组成有Co₃Ti和BCC结构的AlFe固溶相,出现典型的成分均匀的网状调幅分解组织;退火后的平均显微硬度达到989HV_0.5,比退火前提高了73.5%;耐磨性测试结果显示,退火后磨损量比退火前降低了92.5%,磨损宽度是退火前的50%。     

Morphological,Structural and Optical Evolution of Ag Nanostructures on c-Plane GaN Through the Variation of Deposition Amount and Temperature

Owing to their tunable properties, Ag nanostructures have been widely adapted in various applications and the morphological control can determine their performance and effectiveness. In this work, we demonstrate the morphological and optical evolution of Ag nanostructures on GaN (0001) by the systematic control of deposition amount at two distinctive annealing temperatures. Based on the Volmer–Weber and coalescence growth models, the nanostructure growth commenced by the thermal solid-state-dewetting evolve in terms of size, density and configuration. At 450 °C, the round-dome shaped Ag nanoparticles (regime I), irregular Ag nano-mounds (regime II) and void-layer structures (regime III) are observed along with the gradually increased deposition amount. As a sharp distinction, the solid state dewetting process occur more radically at 700 °C and also, the Ag sublimation and the effect on the nanostructure formation are observed in a clear regime shift scaled by the deposition amount. Meanwhile, a strong dependency of reflectance spectra evolution on the Ag nanostructure morphology is witnessed for both sets. In particular, Ag dipolar resonance peaks are significantly red-shifted from VIS to NIR regions along with the nanostructure evolution. The reflectance, PL and Raman intensity variation are also observed and discussed based on the evolution of Ag nanostructures.     

沉积压力对磁控溅射La-Ti/WS2复合薄膜结构和摩擦学性能的影响

目的研究不同沉积压力对磁控溅射La-Ti/WS_2复合薄膜微观结构及摩擦学性能的影响。方法采用非平衡射频磁控溅射法制备WS_2薄膜和La-Ti/WS_2复合薄膜。利用扫描电镜(SEM)和X射线衍射仪(XRD)对薄膜微观形貌、成分和晶向结构进行表征。用纳米压痕仪、摩擦磨损试验机和白光干涉三维形貌仪测试薄膜的力学性能和摩擦磨损性能。结果掺杂La和Ti可以改善WS_2复合薄膜的微观结构。在给定的沉积压力下,La-Ti/WS_2复合薄膜均呈岛状生长模式,组织均匀,且排列较为紧凑,结构致密性好。随着沉积压力的增大,WS_2(002)衍射峰向高θ值偏移,晶面间距减小,晶格发生收缩。复合薄膜的硬度和弹性模量随着沉积压力的增大,先增大后减小。沉积压力为1.2 Pa时,La-Ti/WS_2复合薄膜的摩擦系数低至0.07左右,磨损率低至2.45×10~(–8) mm~3/(N·m)。结论沉积压力对La-Ti/WS_2复合薄膜的性能有较大影响,合适的沉积压力可以提升La-Ti/WS_2复合薄膜的摩擦磨损性能。     

退火及深冷处理对SLM成形ZL114A合金组织及性能的影响

以选区激光烧结(SLM)成形ZL114A合金为研究对象,进行了SLM成形ZL114A合金的退火和深冷处理工艺试验,主要研究了退火温度和深冷保温时间对SLM成形ZL114A合金微观组织和力学性能的影响。结果表明,230℃×2h退火处理后,SLM成形ZL114A合金的伸长率提高了18.0%,抗拉强度下降了2.9%;300℃×2h退火处理导致合金的抗拉强度和伸长率下降了28.2%和22.3%;合金退火态的微观组织表现为α-Al与Si相交界处存在大量的孔洞。而深冷处理(-196℃)对SLM成形ZL114A合金的力学性能有明显改善,其中深冷保温36h对力学性能提升效果最佳,相较沉积态,其抗拉强度提高了18.9%,伸长率提高了23.0%;其深冷态的共晶Si在基体中分散更均匀,并转为棒状结构,使合金的塑性得到明显提高。     

Effects of Annealing on the Microstructure and Properties of 6FeNiCoCrAlTiSi High-Entropy Alloy Coating Prepared by Laser Cladding

The content of each constituent element in the newly developed high-entropy alloys is always restricted in equimolar or near-equimolar ratios to avoid the formation of complex brittle phases during the solidification process. In this article, a high-entropy alloy coating of 6FeNiCoCrAlTiSi has been prepared by laser cladding and subsequently annealed at 500, 750, 1000, and 1150 °C for 5 h. Surprisingly, the coating has a simple BCC solid solution phase with high microhardness, good resistance to softening, and high electrical resistivity properties. After annealing <750 °C, the coating shows high thermal stability, the electrical resistivity decreases slightly and the microhardness almost remains unchanged. After annealing above 750 °C, the microhardness of the coating slowly decreases with the decomposition of the supersaturated BCC solid solution.     

Effect of Annealing on Microstructure and Mechanical Properties of Ultrafine-Grained Low-Carbon Medium-Manganese Steel Produced by Heavy Warm Rolling

An ultrafine-grained(UFG) low-carbon medium-manganese steel was fabricated by the heavily warm rolling(HWR) and subsequent quenching, and the effects of annealing temperatures on microstructure and mechanical properties of the UFG HWRed steel were investigated. The results show that the HWRed steel exhibits simultaneous improvements in strength,uniform elongation and work hardening, which is mainly attributed to the refinement of martensitic microstructures. The HWRed steels comprise only a-phase when annealing at lower temperatures below to 550 °C and at higher temperatures above to 700 °C. Whereas, UFG c-austenite is formed by reverse transformation when the HWRed steel was annealed at intermediate temperatures from 550 to 700 °C and the volume fraction increases with increasing annealing temperatures,consequently resulting in a dramatic increase in ductility of the annealed HWRed steels. It was found that the transformed UFG austenite and ferrite remained ～500 nm and ～800 nm in size when the HWRed steel was annealed at 650 and700 °C for 1 h, respectively, showing an excellent thermal stability. Moreover, the HWRed steel annealed at 650 °C exhibits high strength-ductility combinations with a yield strength of 906 MPa, ultimate tensile strength(UTS) of1011 MPa, total elongation(TEL) of 51% and product of strength and elongation(PSE: UTS 9 TEL) of 52 GPa%. It is believed that these excellent comprehensive mechanical properties are closely associated with the UFG austenite formation by reverse transformation and principally attributed to the transformation-induced plasticity(TRIP) effect.     

Effect of Thermal Annealing on the Physical Properties of Zn1-xCuxSe Thin Films Deposited by Close Spaced Sublimation Technique

Thin films of Zn1-xCuxSe （x= 0.00, 0.05, 0.10, 0.15, 0.20） were grown on glass substrates by closed space sublimation technique. The deposited films were annealed at 200 ~C and 400 ~C in air for 1 h. The annealed samples have been investigated through Rutherford backscattering spectroscopy （RBS）, X-ray diffraction （XRD）, spectroscopic ellipsometer, spectrophotometer and Raman spectroscopy. Through RBS, the composition of the films was calculated and compared with the initial concentration. Structural characteriza- tion including crystal structure, crystal orientation, lattice parameter, grain size, strain and dislocation density were carried out using XRD data. From XRD spectra it was revealed that the as-deposited and annealed films were polycrystalline in nature with zinc-blende structure. However, the crystallinity and the grain size were improved with the increase of annealing temperature. According to Raman spectroscopy, it was observed that as deposited and annealed samples have the same characteristic vibrational modes of ZnSe at low and high frequency optical phonon modes while another mode was observed for 400 ℃ annealed samples at 745 cm-1. Spectroscopic ellipsometer has been used to found annealing effect on the optical properties of ZnSe. The band gap energy has been determined using transmission spectra. It was found that the band gap energy of the film increased with the increase of annealing temperature.     

离子源循环轰击对磁控溅射TiN薄膜结构和电学性能的影响

为研究离子源循环轰击对薄膜结构和电学性能的影响,通过离子源轰击辅助直流磁控溅射在200℃下沉积不同循环周期Ti N薄膜,采用场发射扫描电镜、原子力显微镜、X射线衍射仪表征薄膜表面形貌及组织结构。采用纳米压痕仪检测涂层的硬度和弹性模量。采用双电测四探针电阻仪测试室温下薄膜的电学性能。结果表明:离子源轰击在薄膜中形成了分层结构,膜层更加致密光滑,平均粗糙度由5.2 nm下降为2.7 nm。随着离子源循环轰击周期增加薄膜结晶性增强,并且当离子源循环轰击周期为3次时出现了Ti N(200)峰,薄膜硬度和弹性模量提高。当经过2次离子源循环轰击时薄膜电阻值最低为8.1μΩ·cm。     

Effects of thermal treatment on the characteristics of boron and tantalum-doped ZnO thin films deposited by the electrospraying method at atmospheric pressure

Metal-doped (B and Ta) ZnO thin films were deposited by the electrospraying method onto a heated glass substrate. The structural, electrical and optical properties of the films were investigated as a function of dopant concentration in the solution and also as a function of annealing temperature. The results show that all the prepared metal-doped ZnO films were polycrystalline in nature with a (0 0 2) preferred orientation. As the amounts of dopant were increased in the starting solution, the crystallinity and transmittance decreased. On the other hand, heat treatment of the films enhanced the transmittance, Hall mobility, carrier concentration and crystallinity. It was also observed that 2 at.% is the optimal doping amount in order to achieve the minimum resistivity and maximum optical transmittance. As-deposited films have high resistivity and low optical transmittance. The annealing of the as-deposited thin films in air resulted in the reduction of resistivity. Depending on the characteristics of dopant, mainly ionic radius, the effects of dopant were studied on the properties of ZnO thin films. Boron and tantalum have been considered as dopants, tantalum being the superior of the two, since it showed the lower resistivity and higher carrier concentration as well as higher mobility. The minimum value of resistivity was 1.95 × 10^− 4 Ω cm (15 Ω/□) with an optical transmittance more than 93% in the visible region and minimum resistivity of 2.16 × 10^− 4 Ω cm (18 Ω/□) with an optical transmittance greater than 96% for 2 at. % tantalum- and boron-doped ZnO films respectively. The present values of resistivities were closer to the indium tin oxide (ITO) resistivity and also closest to the lowest resistivity values among the ZnO films that were previously reported. The prepared films exhibit the good crystalline structure, homogenous surface, high optical transmittance and low resistivity that are preferable for optical devices.