退火温度对原子层沉积TiO2薄膜结构、形貌和光学性能影响

采用原子层沉积技术(ALD)在石英衬底上制备了TiO₂薄膜,并对其进行不同温度的快速光热退火处理。采用X射线衍射仪(XRD)、拉曼(Raman)光谱、扫描电子显微镜(SEM)、原子力显微镜(AFM)和紫外-可见分光光度计(UV-Vis)对薄膜进行表征。研究了退火温度对薄膜结构、表面形貌和光学性能的影响。结果表明：当薄膜未退火时,其具有非晶态性质;薄膜在300～600℃的范围下退火时,其具有结晶态性质。当样品在未退火下,其表面粗糙度和光学带隙分别为17.226 nm和3.57 eV;随着退火温度不断升至600℃时,薄膜的表面粗糙度增至30.713 nm变大,晶粒尺寸增至24.75 nm,光学带隙减至3.41 eV。此外,样品的折射率和消光系数随着退火温度的升高呈下降趋势。在实验条件下,最佳退火温度为600℃。     

锶掺杂氧化锌薄膜的制备及其可见光催化性能研究

采用超声辅助喷雾热解法,在400℃玻璃衬底上,制备了一系列不同锶掺杂量的氧化锌(SZO)薄膜,通过XRD、SEM、EDX、UV-Vis吸收谱和PL对样品的结构、表面形貌、元素组成和光学特性进行了表征,并研究了其可见光催化性能。XRD显示,所有薄膜样品皆为六角纤锌矿结构且呈现c轴择优取向,没有观察到其他杂相的衍射峰。UV-Vis吸收谱显示,锶掺杂使得氧化锌薄膜样品在可见光区的光吸收性能增强。样品的室温PL谱中,均可观察到380 nm附近的紫外发光峰和500 nm附近的绿发光峰,并且随着锶掺杂量的增加,绿发光峰明显增强。光催化测试结果显示,前驱体溶液中n(锶)/n(锌)为3%时,制得的SZO薄膜可见光催化活性最高。     

钙掺杂钛酸铅陶瓷纤维的制备与表征

利用溶胶-凝胶法制备了钙掺杂钛酸铅系陶瓷纤维,并通过FT-IR、XRD、SEM研究了钙掺杂对钛酸铅纤维的微观结构、晶胞参数、晶粒尺寸及表面形貌的影响。结果表明,钙的掺入会降低钛酸铅的结晶温度,并可促使钛酸铅由四方相向立方相转变,组成纤维颗粒随着钙掺入量的增加逐渐减小,表面逐渐变得光滑、致密,同时考察了烧结过程中不同退火温度、退火时间、升温速率对钙掺杂钛酸铅陶瓷纤维的影响,最终确定了制备均匀、致密、光滑的陶瓷纤维的烧结条件。     

ZnO薄膜光催化降解苯酚实验

采用溶胶-凝胶法分别在普通玻璃和石英玻璃基底上制备出性能优良的ZnO薄膜,并通过XRD、AFM和UV-V is吸收光谱对薄膜进行表征,进一步研究了不同波长紫外光照射、不同基底及不同退火温度对薄膜光催化性能的影响。实验结果表明,以石英为基底,退火温度为400℃的ZnO薄膜具有更好的光催化氧化能力,并且实现了催化剂的固载,便于回收再利用,催化效果显著。     

溶胶-凝胶法制备钛酸锶钡铁电薄膜的研究

钛酸锶钡(BST)薄膜是一类重要的铁电薄膜材料。采用溶胶-凝胶法制备了不同组分的具有钙钛矿结构的BST薄膜。利用X射线衍射技术(XRD),研究了不同退火条件下BST薄膜的结晶特性,结果表明制备的BST薄膜形成了单一的钙钛矿结构;利用扫描电子显微镜(SEM)和原子力显微镜(AFM)观察了薄膜的表面形貌,结果表明制备的BST薄膜光滑,平整,无明显的孔洞和裂纹,且生长良好。BST薄膜的晶粒细致,排列整齐,分布均匀,呈现球状。     

低含量铁掺杂纳米TiO_2薄膜的制备及其抗菌机理研究

采用溶胶凝胶-浸渍提拉法,制备了玻璃基底上生长的Fe/TiO2薄膜.利用XRD、XPS、AFM等对样品进行表征,研究了铁掺杂对TiO2薄膜晶体结构和表面形貌的影响,并研究了不同掺铁量TiO2薄膜对大肠杆菌的抗菌性能.结果表明,铁掺杂TiO2薄膜的抗菌性能均优于纯TiO2薄膜,其中掺铁量为0.1%时薄膜的抗菌性能最佳,高达98%.     

氮掺杂对二氧化钛光催化性能的影响

采用溶胶-凝胶法,以硝酸铵为氮源,制备了氮掺杂二氧化钛薄膜,通过紫外可见吸收光谱(UV-VIS)、扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)对氮掺杂二氧化钛进行表征,并以亚甲基蓝为降解模型,探讨了氮掺杂对二氧化钛光催化性能的影响。结果表明:当氮掺杂量为11%、煅烧温度为450℃时,其吸收光谱明显发生红移,样品的光催化活性最好。随着氮掺杂量的增加,薄膜的催化性能先增后减,主要原因是氮掺杂会影响晶相颗粒的生长和产生缺陷,薄膜表面更加粗糙,比表面积增大。煅烧温度对薄膜的催化性能的影响也呈现先增后减,因为煅烧温度会影响二氧化钛晶型的转变和结晶度的变化。     

La1-xCaxMnO3团簇薄膜的介电和光学性质研究

利用溶胶-凝胶法制备La1-xCaxMnO3薄膜.利用X射线衍射(XRD)、反射偏光显微镜和电感-电容-电阻测定计(LCR)仪对其结构、形貌和性质进行表征.XRD结果表明薄膜为钙钛矿结构,经不同温度退火后发生微小偏离.偏光显微图像显示薄膜表面形貌为菊花状团簇;经不同温度退火后的薄膜反射色有很大差异,因此反射色不能作为鉴定La1-xCaxMnO3的依据.随着退火温度升高,薄膜的介电损耗降低,说明高的温度退火后,薄膜质量较高.     

纳米二氧化钛薄膜的制备及其光催化性能

采用水热法制备了纳米二氧化钛溶胶,然后采用旋涂法制备了其纳米薄膜。通过X-射线衍射(XRD)和原子力显微镜(AFM)对样品进行了表征;XRD结果表明:通过控制反应条件可以制备不同晶型的纳米二氧化钛。AFM的表征结果表明:所制备的混晶型二氧化钛粒径在32 nm以下,锐钛矿型的二氧化钛粒径在4 nm以下,掺杂二氧化硅的二氧化钛粒径在160 nm以下,掺杂负离子粉的二氧化钛粒径在10 nm以下。对甲基橙的降解实验表明:掺杂负离子粉的二氧化钛的光催化性能最好。     

退火温度对MoS2纳米薄膜微特性及光学性能的影响

本论文使用射频磁控溅射法在硅衬底上制备不同退火温度下的MoS2薄膜,利用SEM、XRD、光谱仪等手段对薄膜的表面形貌、结构、反射率等进行表征,分析退火温度对MoS2薄膜性能的影响。研究结果表明:退火温度对MoS2薄膜表面形貌影响明显,不同退火温度会改变MoS2薄膜XRD衍射峰的位置。退火温度越高,MoS2薄膜生长质量越好,MoS2薄膜反射率越高。     

SrBi4Ti4O15薄膜的溶胶凝胶制备及其生长行为

以氯化锶、硝酸铋和钛酸丁酯为原料,柠檬酸为络合剂,配制了稳定的SrBi4Ti4O15（SBTi）前驱液.采用层层快速退火工艺,在Pt/Ti/SiO2/Si基片上制备了a轴取向增强的SBTi铁电薄膜,通过场发射扫描电镜、环境扫描电镜及X射线衍射等微观分析手段研究了保温时间和成膜次数对薄膜结晶性、微观结构和生长行为的影响.结果表明：层层快速退火工艺,可有效抑制焦绿石相的形成.随着退火时间的延长,薄膜的结晶性变好;但退火时间延长到30 min以上,薄膜的结晶性变差.由于SBTi晶体生长的各向异性及单层膜厚对晶体沿[119]方向生长的限制,随着涂覆次数的增加,SBTi薄膜（119）峰和（200）峰的强度逐渐增大,而（00l）峰的强度反而略有减少,从而使I（200）/I（119）、I（200）/I（0010）、I（119）/I（0010）逐渐增大.     

Influence of sputtering gas pressure on the LiCoO2 thin film cathode post-annealed at 400 °C

LiCoO₂ thin film cathodes were prepared by RF magnetron sputtering and post-annealing. The surface morphological change of the LiCoO₂ thin film wasin-situ measured by hot stage SEM with increasing temperature. The effects of sputtering gas pressure and post-annealing at low temperature (400 °C) were investigated by XRD, AFM, ICP-AES and RBS. The electrochemical characteristics of LiCoO₂ thin films were changed with variation of sputtering gas pressure. A difference of micro-structural evolution after post-annealing was observed, which related to the thin film properties. The electrochemical analysis revealed that the optimal sputtering gas pressure with the low temperature annealing step increases cell capacity and rate capability.     

Crystallization Behavior of Sol–Gel-Derived Strontium Barium Niobate Thin Films

The crystallization of sol–gel-derived strontium barium niobate (SBN) thin films on various substrates is enhanced by a two-step heating process. Also, SBN films with c -axis preferred orientation are obtained on MgO (100) substrates. The crystallized phase and the degree of orientation are dependent on crystallization temperature and film composition. The crystallization temperature required to form a single tetragonal tungsten bronze (TTB) SBN phase increases with an increase of Sr content due to the distorted SBN structure. However, in the case of the film on MgO substrate, the oriented crystallization which forms the single tetragonal phase occurs at a lower crystallization temperature than those of polycrystalline films because of lattice matching between the film and the substrate. Its optical and ferroelectric properties were also investigated. They vary depending on film composition, due to the effect of the distorted SBN structure.     

Chemical solution deposition of pure and Gd-doped ceria thin films: Structural,morphological and optical properties

High quality smooth, uniform and crack-free ceria and gadolinium doped ceria (GDC) thin films were prepared on Si and Si/YSZ substrates by chemical solution deposition. The thermal behavior of Gd-Ce-O precursor was investigated by TG-DSC measurements. The phase purity and structure of deposited films were evaluated using X-ray diffraction (XRD) analysis and Raman spectroscopy. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed for the estimation of surface morphological features. Oxidation state of Ce ions in fabricated films was analyzed by X-ray photoelectron spectroscopy (XPS). Optical properties were evaluated by diffuse reflectance UV–vis spectrometry. Thickness of the films can be controlled by applying a certain number of spin coating cycles. A linear relation between the thickness of the films and the number of deposited layers was observed. The single-layer thickness was determined to be approximately 20 nm. The influence of annealing temperature and Gd content on the film structure, morphology and optical properties was studied and discussed. The dependence of an optical band gap as a function of grain size was demonstrated.     

溶胶-凝胶法制备TiO2-SiO2复合薄膜的波导特性研究

研究了采用溶胶－凝胶法制备的ＴｉＯ２－ＳｉＯ２复合薄膜的波导特性。结果表明随着ＴｉＯ２含量和热处理温度的提高,薄膜的波导损耗增大。ＦＴ－ＩＲ光谱,ＸＲＤ和ＡＦＭ分析表明：这种损耗主要来自于薄膜中的微区不均匀和由于薄膜表面的粗糙度增大而产生的光散射的影响。通过航向光谱计算得到了薄膜的折射率和消光系数和色散关系以及它们与工艺之间的关系。     

Effect of Pd content on crystallization and shape memory properties of Ti–Ni–Pd thin films

The Pd content dependence of the crystallization process of Ti–Ni–(19.1–35.3)Pd (at. %) thin films fabricated by a sputter-deposition method was investigated. Ti–Ni–(19.1–26.1)Pd (at. %) as-deposited thin films were found to be amorphous, whereas Ti–Ni–(29.1–35.3)Pd (at. %) thin films were crystalline in the as-deposited condition. Both the crystallization temperature and activation energy for the crystallization of the amorphous thin films decrease with increasing Pd content. The shape memory effect was confirmed in the in situ crystallized thin film. The finer grain size in the in situ crystallized thin film results in a higher critical stress for slip and a smaller recovery strain when compared with the thin film crystallized by post annealing.     

溶胶-凝胶法制备PZT薄膜晶化过程的跟踪监测

用溶胶－凝胶技术制备了组成在准同型相界点［ｍ（Ｚｒ）／ｍ（Ｔｉ）＝５２／４８］附近的钙钛矿相ＰＺＴ薄膜,并运用原子力显微分析与椭偏法测试相结合的方法跟踪了薄膜的烧结过程．结果表明：钙钛矿相ＰＺＴ［ｍ（Ｚｒ）／ｍ（Ｔｉ）＝５２／４８］薄膜晶化发生于约５５０℃,并伴随着薄膜表面的粗糙化;镀铂硅基片表面粗糙度对ＰＺＴ薄膜的晶化有很大影响．根据ＡＦＭ,ＸＲＤ测试结果,分析了不同热处理条件对ＰＺＴ薄膜微结构及漏电流特性的影响,提出合适的热处理条件．分析了ＰＺＴ薄膜钙钛矿相形成温度高于相应粉体的原因     

Crystallization of amorphous silicon thin films deposited by PECVD on nickel-metalized porous silicon

ABSTRACT: Porous silicon layers were elaborated by electrochemical etching of heavily doped p-type silicon substrates. Metallization of porous silicon was carried out by immersion of substrates in diluted aqueous solution of nickel. Amorphous silicon thin films were deposited by plasma-enhanced chemical vapor deposition on metalized porous layers. Deposited amorphous thin films were crystallized under vacuum at 750 [DEGREE SIGN]C. Obtained results from structural, optical, and electrical characterizations show that thermal annealing of amorphous silicon deposited on Ni-metalized porous silicon leads to an enhancement in the crystalline quality and physical properties of the silicon thin films. The improvement in the quality of the film is due to the crystallization of the amorphous film during annealing. This simple and easy method can be used to produce silicon thin films with high quality suitable for thin film solar cell applications.     

Influence of postdeposition annealing on the properties of ZnO films prepared by RF magnetron sputtering

ZnO films were prepared on unheated silicon substrate by RF magnetron sputtering technique. Postdeposition annealing of ZnO films in vacuum were found to improve film structure and electrical characteristics, such as dense structure, smooth surface, stress relief and increasing resistivity. Suitable annealing temperature also reduced loss factor. The correlation between annealing conditions and the physical structure of the films (crystalline structure and microstructure) was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The preferred annealing condition has been found to improve ZnO film characteristics for piezoelectric applications. An over-mode acoustic resonator using the ZnO film after annealing at 400 °C in vacuum circumstance for 1 h showed a large return loss of 42 dB at the center frequency of 1.957 GHz.