退火温度对Al、Cu、Ni诱导Si薄膜晶化进程的影响

基于金属诱导晶化方法,利用直流磁控溅射离子镀技术制备了Al-Si、Cu-Si和Ni-Si薄膜.采用真空退火炉和X射线衍射仪于不同温度下对样品进行了退火试验并分析了退火后薄膜物相结构的变化规律.结果表明,Al诱导SAi薄膜晶化的效果最好,Cu次之,Ni诱导Si薄膜晶化的效果较差;AI可在退火温度为400℃时诱导Si薄膜晶化,且随退火温度的升高Si的平均晶粒尺寸增大;Cu-Si薄膜的内应力较大和Ni-Si薄膜中Ni/Si界面处难以形成NiSi2是Cu、Ni诱导Si薄膜晶化效果较差的主要原因.     

非晶态Ni-P合金的晶化温度与预存晶核的关系

用经典的相变理论(J-M-A方程)导出了由核长大主导的非晶态合金晶化的峰值温度(T_P)与预存晶核密度(N_0)之间的关系式: T_P~2exp(-Eg/RT_P)=L/N_0~(1/3)其中Eg为核长大激活能,L为常数,R为气体常数.通过对非晶Ni-P合金的预退火处理,获得预存晶核密度不同的非晶态样品,在DSC上测量这些样品的晶化温度.结果表明,上述关系式与实验结果符合很好,利用此关系式可估算出核长大速率常数(U_0),讨论了预退火处理对晶化开始温度T_x及△T_(Px)=T_P—T_x的影响.     

退火温度对Al(Ce)诱导Si薄膜晶化过程的影响研究

基于铝诱导晶化方法,通过直流磁控溅射离子镀技术利用纯Al、纯Si和Al(Ce)靶材,制备了Al-Si和Al(Ce)-Si薄膜.采用真空退火炉和X射线衍射仪在不同温度下,对样品进行了退火实验并分析了Al-Si和Al(Ce)-Si薄膜的晶化和生长过程;结合Si薄膜的生长机理,研究了Al和稀土Ce在对Si薄膜退火晶化过程中的...     

等离子辅助电子束蒸发La2O3薄膜的制备

采用等离子辅助电子束蒸发,在Si(100)衬底上沉积La2O3薄膜.随后对非晶的沉积态薄膜在750℃和900℃分别退火1 h.实验结果表明,采用等离子辅助电子束蒸发,可以获得非晶态的La2O3薄膜;经750℃热处理后,薄膜部分晶化;经900℃热处理后,薄膜显著晶化,晶粒尺寸明显增大,并沿(002)方向择优取向.对薄膜I-V特性的测量结果表明,沉积态薄膜具有较小的漏电流,但随着热处理温度升高,薄膜晶化程度提高,薄膜漏电流逐渐增大;对薄膜透过率的测量结果表明,单面抛光的Si衬底上沉积La2O3薄膜,在近红外范围内有明显的增透效果,最大可达20%左右.     

ZnO掺杂对ZnSb相变薄膜结构和电学特性的影响

目的通过掺杂不同量的ZnO提升ZnSb相变薄膜的晶化温度和晶态膜电阻。方法采用磁控溅射双靶共溅方式制备不同含量ZnO掺杂的ZnSb薄膜,使用真空四探针设备原位测试薄膜电阻随温度的变化情况,用EDS、DSC、XRD、Raman、FESEM、UV-Vis分别对薄膜的成分、晶化温度和熔点、掺杂薄膜的结构、薄膜厚度、表面形貌以及光学带隙进行分析。结果 ZnO掺杂量为1.6%时,Zn O掺杂提升了薄膜的晶化温度和晶态薄膜的电阻,并抑制了ZnSb晶粒的长大。薄膜的晶化温度由253℃提升至263℃,光学带隙由0.37 eV提升至0.38 eV,掺杂薄膜晶粒大小为20 nm左右,远低于未掺杂的50 nm。掺杂薄膜内的O原子更易与Sb结合,过多的Zn O掺杂会使薄膜结晶后形成Sb_2O_3晶粒,使薄膜的晶化温度下降。结论低含量ZnO掺杂的ZnSb薄膜具有更高的晶化温度、更细小的ZnSb晶粒以及更高的膜电阻;过量的Zn O掺杂使薄膜在结晶后产生分离的Sb_2O_3相,恶化薄膜性能。     

用TEM研究非晶态Ni—P合金薄膜原位加热时的动态晶化过程

本文采用原位加热透射电子显微镜观察技术研究了非晶态Ni-P合金薄膜的动态晶化过程。实验结果表明,非晶态合金薄膜在等温退火时,首先在非晶态基体中产生微小的有序原子集团,并长大成取向无规的Ni_3P晶体微粒;然后是晶体的形成和长大。在晶体长大过程中这些晶体微粒通过切变(取向变化)直接沉积在晶体前沿上,而保持其结构形态不变。利用动态录像技术测量了晶化过程中的晶体长大过程,发现晶体在长大过程中有“台阶型”长大,这种“台阶型”长大过程对应于有序原子集团的切变沉积,不同温度下有序原子集团切变沉积使晶体长大速率的变化不同。     

SmCo薄膜的不均匀晶化及其磁性能

采用不同的磁控溅射和回火工艺制备了SmCo磁性薄膜.用能谱仪对不同工艺溅射的样品进行了化学成分分析; 用透射电子显微镜和振动样品磁强计(VSM)研究了薄膜的显微结构和磁性能.结果表明: 溅射态的薄膜为非晶态并具有软磁特征; 当回火温度位于400～ 450℃之间时, 薄膜的微观组织均匀细小, 且随着回火温度增加, 矫顽力增大, 并在450℃回火的样品中得到了最大的矫顽力.回火温度500℃后, 薄膜微观组织中晶粒出现了不均匀粗化, 矫顽力明显降低.     

非晶态合金晶化过程的一种新微观机制SCIEI

根据对非晶态合金微观结构的分析和原位加热TEM观察非晶态Ni-P合金薄膜动态晶化过程的实验结果,本文提出了一个新的晶化微观机制,即非晶态合金的晶化过程由两个不同过程组成;(1)单原子由非晶态问晶胚(或晶体)表面的扩散过程;(2)有序原子团的长大及切变合并或切变沉积过程。部分晶化非晶态Ni-P合金的TEM观察结果为新晶化微观机制的适用性提供了证据。并用此机制解释了晶化过程中的初生晶体结构形态等实验结果。     

NiTi形状记忆合金薄膜的相结构

采用直流磁控溅射法制备了NiTi形状记忆合金薄膜,采用一步法对NiTi薄膜进行晶化热处理以使其获得形状记忆效应,研究了成分和晶化热处理对NiTi薄膜相结构的影响.结果表明,等原子比膜和富钛膜经相同晶化热处理后,相结构明显不同,前者相结构主要为B2相,后者则为B2+M相;且等原子比膜经过不同温度的晶化热处理后,随着温度的升高,M相和第二相也相应增多.     

非晶晶化法制备纳米晶Fe36Co36B20Si4Nb4

利用铜模注射法和铜模吸铸法分别制备出了杆状和管状的非晶态Fe36Co36B20Si4Nb4合金;采用非晶晶化法对非晶态Fe36Co36B20Si4Nb4,合金进行了不同保温时间和不同保温温度的等温退火处理.获得了在非晶基体上均匀分布纳米晶的非晶/纳米晶复合材料.运用DSC、XRD和TEM等分析方法和手段.分析和检测了它们的热稳定性、结构特点以及纳米晶的分布情况.     

钛酸铋薄膜的磁控溅射及其退火处理

采用射频磁控溅射技术,在Pt/Ti/SiO2/Si衬底上制备了钛酸铋(Bi4Ti3O12,简称BIT)薄膜。研究了衬底温度及后续退火处理对薄膜结构和表面形貌的影响。结果表明:适宜的衬底温度为200℃。随着退火温度(650~800℃)的升高,BIT薄膜的结晶性变好,晶粒尺寸增大,c轴取向增强。当退火温度达到850℃时,开始出现焦绿石相;700~800℃为适宜的退火温度,在此条件下得到的BIT薄膜结晶良好,尺寸均匀,表面平整致密。     

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.     

退火温度对锗薄膜光学性能和表面结构的影响

研究了退火温度对电子束蒸发制备的锗薄膜光学性能和表面结构的影响规律.在硅基底上制备了厚度约850 nm的Ge薄膜,分别在350、400、450和500℃下进行退火.通过红外光谱仪测试了薄膜的透射率变化,采用光谱反演法得到了薄膜折射率和消光系数的变化规律,使用X射线衍射和原子力显微镜测试了样品的结晶特性和表面形貌.结果 ...     

溅射气压对ZnO透明导电薄膜光电性能的影响

采用射频磁控溅射方法,在普通玻璃上制备了具有高度c轴取向的ZnO薄膜,研究了溅射气压(0.2～1.5 Pa)对ZnO薄膜的微观结构和光电性能的影响.AFM、XRD、UV-Vis分光光度计及四探针法研究表明:随着溅射气压的增大,ZnO薄膜沿c轴方向的结晶质量提高,晶粒细化,薄膜表面更加致密,晶粒大小更加均匀;ZnO薄膜在400～900nm范围内的平均透过率均高于85%,其中在0.5～1.5 Pa范围内其透过率高于90%;样品在高纯氮气气氛中经350 ℃,300 s退火后,电阻率最低达到10-2 Ω-cm量级.     

纳米V2O5薄膜的制备与特性

采用溶胶.凝胶法在Si和普通玻璃基底上制备V2O5纳米薄膜.在空气中对样品进行不同温度的退火处理.利用X射线衍射、扫描电子显微镜和分光光度计对制备的V2O5薄膜的结构、形貌和光学特性进行研究.XRD和SEM研究结果表明:可以通过升高退火温度来提高薄膜的结晶程度、颗粒尺寸及其均匀程度,并增强V2O5的择优取向性.透射谱和吸收谱的研究结果表明:随着退火温度的升高,V2O5薄膜的吸收边缘发生红移,光学带隙逐渐变窄.     

Crystallization of Mg-based bulk metallic glass

1 Introduction Since INOUE et al[1,2] reported that amorphousalloy with the composition of Mg65Cu25Y10 could beproduced with thickness up to 4 mm by conventionamold casting technique, Mg-based bulk metallic glasses(BMGs) have been proposed as a new kind …     

Morphological, structural, and mechanical characterizations of InGaN thin films deposited by MOCVD

Presented in this study are surface roughness, crystalline structure, and nanomechanical properties of InGaN thin films deposited under various growth temperatures, obtained by means of X-ray diffraction (XRD), atomic force microscopy (AFM), and nanoindentation techniques. The InGaN thin films with different In contents were deposited on sapphire substrates through a metal-organic chemical-vapor deposition (MOCVD) system. Changes in mechanical properties for InGaN thin films are discussed in conjunction with deposition temperature, surface morphology and crystalline structure. The XRD measurements showed that there was no phase separation of In as the In composition went from 25 at.% to 34 at.%. Moreover, both XRD and AFM showed larger grain and surface roughness in In_0.25Ga_0.75N thin films. Nanoindentation results indicate that hardness and Young's modulus both decreased as the indentation depth increased. The contact stress–strain relationships were also analyzed.     

退火工艺对二氧化钛薄膜光催化性能的影响

利用磁控溅射法制备得到二氧化钛薄膜,将薄膜在高温管式炉中分别进行退火,利用XRD、AFM和紫外-可见光谱仪研究了不同温度下退火前后薄膜的晶相结构、光学性能和光催化性能。结果表明,随着退火温度的升高二氧化钛的晶相由锐钛矿向金红石转变,600℃时为两相共存,表面颗粒大小也会有相应变化,锐钛矿相表现出了更好的光催化性能。     

Small angle X-ray scattering studies on structural evolution during calcination of sol–gel ITO nano-powders

ITO nano-powders are prepared by sol–gel method followed by a calcination process. The microstructure responses with thermal treatments are performed by the control of annealing temperature and holding time, and the structures are characterized by small angle X-ray scattering (SAXS) and X-ray diffraction (XRD) technique. It is found that, the structural evolution shows different characters at low temperature (≤800 °C) and high temperature (>800 °C). At low temperature, sample is densified and has a transition from a hierarchical to a surface fractal structure due to the diffusion and elimination of interaggregate pores with increasing annealing time or temperature. At high temperature, samples all show surface fractal structures at whole length scale and the surface roughness increases due to the growth of crystalline grains with increasing annealing temperature, in contrast the roughness is slowly decreased because of the diffusion along the crystalline boundary with holding time.     

退火工艺对高温叠轧AZ31镁合金板材组织与性能的影响

将高温叠轧变形和退火再结晶相结合,尝试共同调控AZ31镁合金板材的组织与织构。在300℃下对高温叠轧AZ31镁合金板材进行不同时间的退火处理,并研究了退火对高温叠轧板材组织、晶粒取向和力学性能的影响。结果表明:随退火时间的增加,界面结合质量逐渐提高,当退火时间为30 min时,部分区域出现冶金现象;显微硬度随退火时间的增加而降低;延长退火时间,高温叠轧板材非基面取向晶粒比重显著增加,同时,高温叠轧历史累积应变量、后续退火两者共同作用促使AZ31镁合金板材基面织构显著弱化。