温度对非晶硅薄膜二次晶化的影响

为研究温度对固相晶化的影响,用玻璃作衬底,在不同温度下用PECVD法直接沉积非晶硅(a-Si:H)薄膜,把在室温、350℃和450℃下沉积的样品,在600℃和850℃下退火3h,把前后样品用拉曼光谱和扫描电镜分析,发现二次晶化后的晶化效果比直接沉积的薄膜好,850℃下退火的薄膜比600℃好。在450℃下沉积、850℃退火3h,SEM观察,表面最大晶粒尺寸为900nm左右。     

Si(111)上生长LiNbO_3薄膜的研究

利用射频磁控溅射的方法,在Si(111)衬底上制备了LiNbO3薄膜。采用X射线衍射(XRD)和扫描电子显微镜(SEM)研究了衬底温度、退火温度和溅射气体压强对LiNbO3薄膜结晶和表面形貌的影响,并用椭圆偏振仪测量了薄膜的厚度和折射率。结果表明:衬底温度为450℃时制备的薄膜,退火前后都没有LiNbO3相生成;衬底温度为500～600℃时,LiNbO3薄膜出现(012)、(104)和(116)面衍射峰,经600℃退火后3个衍射峰的强度加强;衬底温度为600℃时,经600～900℃退火得到的LiNbO3薄膜,除出现(012)、(104)和(116)面衍射峰外,还出现(006)面衍射峰;溅射气体压强从0.8 Pa增大到2.4 Pa时,经800℃退火后得到的LiNbO3薄膜表面晶粒团簇变小,而0.8 Pa制备的薄膜经800℃退火后LiNbO3相的结晶程度较其它压强下完善;900℃退火后得到的LiNbO3薄膜折射率为2.25,与LiNbO3晶体相当。     

快速退火对ZnTe外延层性能及In电极的影响

研究了在GaAs(001)衬底上外延生长的本征ZnTe薄膜样品在氮气氛中450～550℃下的快速退火行为。对于1 min退火的样品,随着退火温度的升高,ZnTe(004)峰双晶X射线(DCXRD)摇摆曲线的半高宽(FWHM)逐渐下降;样品表面粗糙度均方根值(RMS)由退火前的5.3 nm下降至4.7 nm左右。对于450℃退火5 min的样品,其晶体质量与550℃退火1 min的样品相当,但RMS值下降到4.26 nm。ZnTe薄膜表面的In电极之间在未退火时呈高阻状态,在适当条件下退火后In电极之间可以导通,且随着退火温度的降低,所需的退火时间将延长。但550℃退火时In电极的外观形貌发生改变且不能导通。     

退火温度对溶胶-凝胶法制备的TiO2/石墨烯 复合材料性能影响

为了研究退火温度对TiO2/ 石墨烯复合材料物相结构、微观形貌、光催性能的影响,采用溶胶－凝胶法制备 TiO2/石墨烯复合材料1并分别在350 ℃ 、450℃和550 ℃对复合材料进行退火处理。研究结果表明,随着退火温度的升高,TiO2/石墨烯复合材料的晶粒尺寸逐渐增加,结晶性变好,出现了卷曲状的石墨烯?光催化性能先增大后降低,当退火温度为450℃时,复合材料禁带宽度为2.9ｅＶ,具有最佳的光催化活性。     

退火工艺对La-Nb共掺杂Bi_4Ti_3O_(12)薄膜结构的影响

采用sol-gel法制备了Si基Bi3.25La0.75Ti2.94Nb0.06O12.03(BLTN)铁电薄膜,研究了退火温度、升温速率和退火时间对BLTN薄膜微观结构的影响。结果表明:制备的BLTN薄膜具有单一的钙钛矿结构,且为随机取向,表面平整致密;退火温度由550℃升高到750℃时,薄膜的衍射峰强度增强,晶粒尺寸由65 nm增大到110 nm;退火升温速率由10℃/min提高为20℃/min时,薄膜的晶化程度降低;退火时间对薄膜的晶相结构影响不大,但时间超过30 min会造成薄膜表面孔洞增多、致密性下降。     

铁电薄膜底电极La0.5Sr0.5CoO3的结构及电性能研究

采用溶胶-凝胶(Sol-Gel)法在Si衬底上沉积一层La0.5Sr0.5CoO3(LSCO)薄膜底电极,并在不同的退火温度下表征薄膜的各种性质.X线衍射表明在550～750℃退火温度下制备的LSCO薄膜呈(110)取向的钙钛矿结构;谢乐公式估算薄膜的晶粒尺寸为25～50 nm.扫描电子显微镜(SEM)观察结果显示:薄膜表面平整,结构致密.运用四探针法测量薄膜的体电阻,结果表明,750℃退火温度后渗氧处理可获得电阻率较低的La0.5Sr0.5 CoO3薄膜.     

PECVD制备纳米晶多晶硅薄膜

以Si(100)为衬底,采用磁控溅射和射频等离子体增强化学气相沉积系统制备了Si(100)/Al膜/非晶Si膜结构的样品。对该样品进行Al诱导真空退火以制备多晶硅薄膜,采用X射线衍射仪(XRD)和AFM分析薄膜微结构及表面形貌。实验结果表明,在经过500℃、550℃Al诱导退火后,形成了择优取向为〈111〉晶向的多晶硅薄膜。AFM给出了550℃退火后薄膜表面形貌,为100～200nm大小的圆丘状硅晶粒,密集排列在薄膜表面;并对Al诱导真空退火晶化的机理进行了分析。     

退火温度对BaSn0.94Sb0.06O3 NTC薄膜的影响

采用射频磁控溅射技术成功制备了BaSn0.94Sb0.06O3薄膜,并研究了退火温度对薄膜微观结构及电学性能的影响。薄膜晶体结构呈现（110）晶面取向。在850 ℃退火中,BaSn0.94Sb0.06O3薄膜的表面粗糙度为0.8 nm。该薄膜放在电阻炉（730~850 ℃）中退火,随着退火温度的升高,薄膜电阻率从426.74 Ω·cm急剧下降到31.28 Ω·cm。在790~850 ℃退火时,薄膜呈线性负温度系数(LNTC）热敏电阻。对薄膜进行复阻抗图谱研究。结果表明,随着薄膜退火温度的升高,薄膜晶粒与晶界表现出良好的LNTC热敏性能。     

衬底和退火温度对多晶硅薄膜结构及光学性质影响

通过射频等离子体增强化学气相沉积(RF-PECVD)技术与退火处理制备多晶硅薄膜,研究了衬底和退火温度对所制薄膜的结构及光学性质的影响。本次试验最大的晶粒尺寸是在衬底温度为250℃获得,考虑薄膜表面的质量,最佳的退火温度为635℃,衬底温度为225℃,在玻璃衬底形成的晶粒大于50 nm,光学带隙为1.5 e V。结果表明:衬底温度影响着薄膜中氢含量以及相关的缺陷。随着退火温度的升高,晶化率的提高,光学带隙先减小后增大。     

sol-gel法制备的ZnO:(Al,La)透明导电膜光电性能

通过X射线衍射、紫外–可见分光光度计、扫描电镜和四探针仪分析等手段,考察了退火温度对ZnO:(Al,La)薄膜微观结构、光学和电学性能的影响,Al掺杂浓度对电阻率的影响。结果表明:随退火温度的升高,薄膜(002)晶面择优取向生长增强,平均晶粒尺寸增大,电阻率降低,透光率上升。在x(Al)为1%,退火温度550℃时,薄膜最低电阻率为1.78×10–3?·cm,平均透光率超过85%。     

退火温度对纳米TiO2薄膜微结构的影响

利用XRD、IR、UV-VIS、AFM、XPS等手段,研究了退火温度对溶胶–凝胶法制备的纳米TiO2薄膜微结构和表面形貌的影响。450~600℃退火处理的薄膜呈锐钛矿和金红石型混晶结构,700℃退火后为纯金红石相;水峰的吸收峰消失在300~500℃之间,至500℃有机基团完全消失,薄膜表面主要有C,Ti,O三种元素;改变退火温度,可以使薄膜的禁带宽度在3.26~3.58eV之间变化,可以在一定范围内,获得不同折射率的TiO2纳米薄膜;薄膜的表面粗糙度(RMS)为2~3nm。     

Effect of annealing temperature on structural,electrical and optical properties of spray pyrolytic nanocrystalline CdO thin films

Nanocrystalline CdO thin films were prepared onto a glass substrate at substrate temperature of 300 °C by a spray pyrolysis technique. Grown films were annealed at 250, 350, 450 and 550 °C for 2.5 h and studied by the X-ray diffraction, Hall voltage measurement, UV-spectroscopy, and scanning electron microscope. The X-ray diffraction study confirms the cubic structure of as-deposited and annealed films. The grain size increases whereas the dislocation density decreases with increasing annealing temperature. The Hall measurement confirms that CdO is an n-type semiconductor. The carrier density and mobility increase with increasing annealing temperature up to 450 °C. The temperature dependent dc resistivity of as-deposited film shows metallic behavior from room temperature to 370 K after which it is semiconducting in nature. The metallic behavior completely washed out by annealing the samples at different temperatures. Optical transmittance and band gap energy of the films are found to decrease with increasing annealing temperature and the highest transmittance is found in near infrared region. The refractive index and optical conductivity of the CdO thin films enhanced by annealing. Scanning electron microscopy confirms formation of nano-structured CdO thin films with clear grain boundary.     

磁控溅射法制备Ag/FePt/C/FePt薄膜的结构和磁性能

采用磁控溅射法,在自然氧化的Si(001)基片上沉积了Ag/FePt/C/FePt纳米薄膜,并分别在400,450,500,600℃下对薄膜样品进行了1h的退火热处理。利用X射线衍射仪和振动样品磁强计,对薄膜样品的结构和磁性进行了分析。结果表明,当热处理温度为450℃时,Ag/FePt/C/FePt薄膜中已形成了具有有序面心四方结构的L10-FePt。随着热处理温度的升高,薄膜样品的有序化程度提高,矫顽力Hc增强,晶粒尺寸变大。当热处理温度为600℃时,薄膜样品的平行膜面Hc为905.8kA·m-1,晶粒尺寸为23nm。     

退火温度对PZT薄膜电容器性能的影响

通过简单的溶胶–凝胶法和快速热处理工艺,获得了在Pt/Ti/SiO2/Si基片上生长良好的PZT薄膜。制膜工艺简单,不需要回流和高温去结晶水,即可获得(111)择优取向的PZT薄膜。PZT薄膜经快速热处理在550~650℃退火,薄膜致密和平滑,均具有良好的铁电和介电特性,其最佳退火温度为600℃。     

Al-N共掺杂ZnO:Mn稀磁半导体薄膜的结构与性能

采用反应磁控溅射法在室温下沉积前驱体氮化物,在大气环境、500℃下氧化退火30min后获得了Al-N共掺杂ZnO:Mn薄膜。研究了直流与射频反应磁控溅射对氧化退火薄膜结构和性能的影响。结果表明:两种工艺制备的退火薄膜均具有ZnO纤锌矿结构,且均为n型导电。射频溅射退火样品具有很好的c-轴择优取向,其表面光滑平整,表面粗糙度RMS值为1.2nm,且具有室温铁磁性,饱和磁化强度(Ms)和矫顽力(Hc)分别为46.8A·m–1和4.9×103A·m–1;而直流溅射退火样品表面凹凸不平,RMS值为25.8nm,室温下是反铁磁性的。     

The TCR of Ni24.9Cr72.5Si2.6 thin films deposited by DC and RF magnetronsputtering

The temperature coefficient of resistance (abbreviated as TCR) of thin film resistors on some sensor chips,such as thermal converters,should be less than several ppm/℃.However,the TCR of reported thin films is larger than 5 ppm/℃.In this paper,Ni_24.9Cr_72.5Si_2.6 films are deposited on silicon dioxide film by DC and RF magnetron sputtering.Then as-deposited films are annealed at 450℃ under different durations in N₂ atmosphere. The sheet resistance of thin films with various thickness and annealing time are measured by the four probe resistivity test system at temperature of 20,50,100,150,and 200℃ and then the TCR of thin films are calculated. Experimental results show that the film with the TCR of only-0.86 ppm/℃ can be achieved by RF magnetron sputtering and appropriate annealing conditions.     

退火温度对Cr-Si压阻薄膜电性能的影响

采用射频磁控溅射法在氧化铝陶瓷基底上制备了Cr-Si-Ni-Ti压阻薄膜,研究了不同退火温度对薄膜电性能的影响.结果表明:在溅射态及退火温度低于600℃时,薄膜为非晶态.随着退火温度的升高,薄膜的电阻温度系数(TCR)逐渐增大,应变因子(GF)先增大后减小,室温电阻率(ρ)则逐渐降低.在退火温度为300℃时,Cr-Si...     

镍酸镧缓冲层的制备及对钙锶铋钛的影响

采用溶胶-凝胶(Sol-Gel)法在Si(100)衬底上制备了LaNiO3薄膜,然后在LaNiO3/Si(100)上制备了钙锶铋钛薄膜。研究了热处理工艺对LaNiO3(LNO)薄膜的影响。研究结果表明,当热分解温度为350℃、退火温度为750℃,厚为250nm时,制备的LNO薄膜的(110)衍射峰取向择优最明显,电阻率也较低,(为1.8×10-3Ω.cm)。LNO缓冲层的引入促进钙锶铋钛薄膜沿A轴方向生长,明显改善了钙锶铋钛薄膜的电性能,即剩余极化强度Pr=15.2μC/cm2,矫顽电场Ec=70kV/cm。     

Effect of thermal annealing on physical properties of vacuum evaporated In2S3 buffer layer for eco-friendly photovoltaic applications

The present communication reports the effect of thermal annealing on the physical properties of In₂S₃ thin films for eco-friendly buffer layer photovoltaic applications. The thin films of thickness 150 nm were deposited on glass and indium tin oxide (ITO) coated glass substrates employing thermal vacuum evaporation technique followed by post-deposition thermal annealing in air atmosphere within a low temperature range 150–450 °C. These as-deposited and annealed films were subjected to the X-ray diffraction (XRD), UV–vis spectrophotometer, current–voltage tests and scanning electron microscopy (SEM) for structural, optical, electrical and surface morphological analysis respectively. The compositional analysis of as-deposited film is also carried out using energy dispersive spectroscopy (EDS). The XRD patterns reveal that the as-deposited and annealed films (≤300 °C) have amorphous nature while films annealed at 450 °C show tetragonal phase of β-In₂S₃ with preferred orientation (109) and polycrystalline in nature. The crystallographic parameters like lattice constant, inter-planner spacing, grain size, internal strain, dislocation density and number of crystallites per unit area are calculated for thermally annealed (450 °C) thin films. The optical band gap was found in the range 2.84–3.04 eV and observed to increase with annealing temperature. The current–voltage characteristics show that the as-deposited and annealed films exhibit linear ohmic behavior. The SEM studies show that the as-deposited and annealed films are uniform, homogeneous and free from crystal defects and voids. The grains in the thin films are similar in size and densely packed and observed to increase with thermal annealing. The experimental results reveal that the thermal annealing play significant role in the structural, optical, electrical and morphological properties of deposited In₂S₃ thin films and may be used as cadmium-free eco-friendly buffer layer for thin films solar cells applications.