PLZT铁电薄膜的制备及其性能

在温度为97℃,水浴回流10h的条件下,用旋涂法在Si（100）基底上,通过改变溶胶的滴加量、转速、升温速率、煅烧温度及保温时间,制备出性能良好的PLZT铁电薄膜,并用精密阻抗分析仪（PIA）对其介电性能进行测试,研究发现：PLZT铁电薄膜未被击穿时,随着测试频率厂的提高电容逐渐减小,而介电损耗会出现突变,在测试频率达到1MHz时,介电损耗一次突变;当PLZT铁电薄膜被击穿时,随着测试频率厂的升高,介电损耗会逐渐增大,在外场频率达到1MHz时开始减小,当膜被击穿后,电感将不可恢复,而材料的电容具有恢复特征,随着测试频率的升高,电容在逐渐减小．     

体系pH对MoO_3薄膜结构及光致变色性能的影响

采用溶胶-凝胶法制备了MoO3光致变色薄膜,主要探讨溶液pH值对薄膜结构及性能的影响,运用XRD、SEM、UV-Vis-DRS及全自动色差计对氧化钼薄膜的结构及性能进行了表征.实验表明:随溶液pH值的升高,MoO3薄膜光致变色性能先增强后减弱.pH=1.0时薄膜结晶度较好,颗粒粒径较小,分布较均匀,激发波长蓝移,薄膜的吸收光波区域变宽,色差值达到2.427,光致变色性能提高.     

Dielectric properties of low dielectric constant Ba0.60Sr0.40Mg0.15Ti0.85O3-Mg2TiO4 composite thin films for tunable applications

Ba0.60Sr0.40Mg0.15Ti0.85O3-xmol%Mg2TiO4 （x = 0-40 mol%） （BSTM-MT） composite thin films were fabricated by sol-gel method. The precursor solution of these composite thin films was prepared through mixing the Ba0.80Sr0.40Mg0.15Ti0.85O3 and Mg2TiO4 solution. The microstructures and dielectric tunability of composite thin films were investigated. The dielectric constant of composite thin films can be tailored from 155 to 55 by changing the concentration of Mg2TiO4. The dielectric loss of these composite thin films were still kept below 0.01 and the tunability was above 20% at a dc-applied electric field of 500 kV/cm. Suitable dielectric constant, low dielectric loss, and high tunability of this kind of composite thin films can be useful for potential microwave tunable applications.     

溶胶凝胶法制备ZnO薄膜及性质研究

以二水醋酸锌为原料,使用溶胶凝胶法在(100)Si衬底上旋转涂敷得到ZnO薄膜.采用傅立叶变换红外光谱和X射线衍射(XRD)分析经N2、空气、O2不同气氛400℃退火ZnO薄膜的成分和结构差异.使用XRD、原子力显微镜和光致发光手段重点研究了N2气氛条件下,ZnO薄膜结构与发光特性随退火温度的变化规律,发现400℃下退火更适于干凝胶薄膜经历结构弛豫,生成具有(002)择优取向、性质优良的纳米晶ZnO薄膜.计算该样品的晶粒尺寸为41.6 nm,晶格常数a=0.325 3 nm,c=0.521 nm,其PL光谱出现495 nm附近强的绿光发射峰,可能源于ZnO纳米晶粒表面缺陷氧空位(Vo).随着退火温度升高,ZnO生成量减少、晶粒体表面积比(S/V)减小共同作用导致绿光峰强度变弱.     

Microstructures and optical properties of sol-gel derived TiO2 anatase thin films

TiO₂ anatase thin films on quartz substrates were prepared with sol-gel method. The dry gel films, made by spin coating 10 times, were calcined at various temperatures. From X-ray diffraction analyses, it is found that the anatase to rutile phase transformation temperature of the films is higher than 850°C, the films are preferentially oriented on (0 0 1) plane, i. e.c-axis oriented. The thickness, refractive indexes, absorption coefficients and extinction coefficients of the films were determined from UV-Vis transmission spectra of the films using a UV-Vis spectrophotometer. The thickness of the films is about 570 nm. The refractive indexes, absorption coefficients and the extinction coefficients of the present films are larger than the values of anatase films prepared by sputtering. This indicates that the films made with sol-gel method are very dense. Biography: LIU Zhong-chi(1967-), male, Master candidate. Research direction: non-linear optical materials.     

溶胶凝胶法制备SnO2掺杂透明导电膜及性能测试

在醇溶剂中,以SnCl4和Si(OEt)4为原料,用溶胶凝胶浸渍法分别制备掺杂锑、氟和锌离子的SnCl2透明导电薄膜,并对其性能进行了测试。结果表明,该方法制得的透明导电薄膜的光电指标性能良好,并且具有工艺简单,生产成本低,适合对大面积和异形基板涂膜的优点。     

纳米TiO2/玻璃膜的制备及其光催化性能

以钛醇盐为原料, 采用溶胶-凝胶法制备了纳米TiO2/玻璃薄膜. XRD、AFM和厚度分析表明,纳米TiO2/玻璃薄膜中TiO2为锐钛矿型结构, 粒径为纳米级, 三层膜的总厚度为200#nm.通过调节热处理温度, 能有效控制薄膜中粒子的大小.UV-VIS吸收光谱表明,TiO2/玻璃薄膜可以有效地降解罗丹明B染料废水,其光催化活性随TiO2粒径的减小而增大,受膜厚增加的影响不大.     

Dielectric properties of low dielectric constant Ba_(0.60) Sr_(0.40)Mg_(0.15)Ti_(0.85)O_3-Mg_2TiO_4 composite thin films for tunable applications

Ba0.60Sr0.40Mg0.15Ti0.85O3-xmol%Mg2TiO4(x=0―40 mol%)(BSTM-MT) composite thin films were fabricated by sol-gel method.The precursor solution of these composite thin films was prepared through mixing the Ba0.60Sr0.40Mg0.15Ti0.85O3 and Mg2TiO4 solution.The microstructures and dielectric tunability of composite thin films were investigated.The dielectric constant of composite thin films can be tailored from 155 to 55 by changing the concentration of Mg2TiO4.The dielectric loss of these composite thin films were...     

SnO_2薄膜的形貌及其电特性分析

我们用ＰＥＣＶＤ方法制备出ＳｎＯ_２薄膜，透射电镜ＴＥＭ分析表明沉积温度由高到低时，ＳｎＯ_２膜从多晶态转变为非晶态，并且其电阻率随之增加；沉积时氧气流量增加时，ＳｎＯ_２的电阻率增加。     

非晶态CuO—SiO2多孔薄膜的湿敏特性

利用溶胶－凝胶工艺和浸渍－提拉法制备了非晶态ＣｕＯ－ＳｉＯ２多孔薄膜湿敏元件,研究陀们的感湿特性,制备的湿敏元件具有响应速度极快、灵敏度高、线性度较好、湿滞小和一致性好等优点。     

具有超薄厚度的多孔介质中非定常的Stokes流的均匀化

主要研究了在三维的多孔介质中具有超薄厚度的多孔介质中非定常的Stokes流的均匀化。经过细致的分析,我们最后论证了当流体区域的厚度充分小时,流体的运动状态满足平面流中的“达西定律”。     

退火温度对TiO2薄膜光学性能的影响

为确定合适的TiO2薄膜退火工艺,研究了退火温度对采用中频交流反应磁控溅射技术制备的TiO2薄膜光学性能的影响.利用分光光度计测得石英玻璃基体TiO2薄膜试样的透射谱和反射谱,用包络线法和经验公式法计算出薄膜的光学常数.结果表明 TiO2薄膜的折射率随退火温度的上升而增加,低温退火时薄膜消光系数略有减小, 500 ℃退火时TiO2薄膜具有最优的光学性能.     

BiFeO3薄膜的sol-gel制备及其铁电性能研究

采用sol-gel方法在Pt(111)/Ti/SiO2/Si(100)衬底上制备出了(100)择优取向的BiFeO3薄膜.XRD研究表明,600～650℃退火的薄膜结晶较好.AFM形貌显示,650℃退火的薄膜中等轴状晶粒大小均匀(直径100～150nm),薄膜较为致密.电学性能测量结果表明,650℃退火、厚度为840nm的薄膜的2Pr值为2.8mC/cm2;在50kV/cm外加电场下,漏电流为2.7×10-5 A/cm2.电流-电压特性显示,在欧姆区之上,薄膜的主要导电机制为波尔-弗兰克尔发射导电.     

用RF—PECVD制备的SnO2薄膜光电性质及化学成分

利用ＸＰＳ研究了ＲＦ－ＰＥＣＶＤ制备ＳｎＯ２薄膜的化学计量配比，测试了ＳｎＯ２薄膜的光学和电加热特性。结果表明：具有导电性能的ＳｎＯ２薄膜是一种非理想化学计量配比的氧化物半导体薄膜材料，薄膜还具有较高的可见光透过率和较好的电加热性能。     

R.F.溅射Ba0.5Sr0.5TiO3薄膜及其光学特性研究

用R．F．磁控溅射法在石英衬底上沉积Ba0.65Sr0.35TiO3薄膜,应用XRD与SEM表征了BST薄膜的晶化行为及其表面形貌．在550℃衬底温度下沉积的薄膜,其表面光滑、晶粒大小分布均匀．应用双光束分光光度计,在200～900nm的波长范围测量了薄膜的透射光谱,并根据“包络法”理论计算薄膜的折射指数．结果表明,随着辐射波长从650nm减小到480nm,薄膜的折射率从2．04增加到2．15;随着波长进一步降低,折射率急速上升,到420nm时,折射率升至2．40,显示出典型的电子带间跃迁的色散曲线．由“包络法”和Tauc关系确定BST薄膜的光学能隙约为3．66eV．     

溶胶-凝胶法制备Ba0.6Sr0.4TiO3薄膜的微结构及介电性能研究

使用部分醋酸盐为原料,用改进的溶胶-凝胶法制备钛酸锶钡(Ba0.6Sr0.4TiO3,BST)薄膜.场发射扫描电镜(FESEM)分析发现,薄膜均匀致密,表面无空洞、无开裂,晶粒尺寸约为50 nm.用原子力显微镜(AFM)测量薄膜表面的方均根粗糙度为7.8 nm.用透射电镜(TEM)观察薄膜的断面结构,用阻抗分析仪测试了薄膜的介电性能,其介电常数和介电损耗分别为460和4%(1 kHz).     

含三氯乙烷干氧气氛中二氧化硅薄层的生长规律

研究了含TOA(三氯乙烷)干氧气氛中,温度在900～1100℃范围内,10～100nm二氧化硅薄层的生长规律。讨论了该规律的解析表达式和有关模型参数。比较了经高温含氧退火和未经高温退火所生长的氧化层的击穿电场强度和可动离子沾污等特性。结果表明,前者优于后者。经含氧退火处理的薄氧化层更适用于小尺寸器件。     

Short-wavelength static optical recording properties of subphthalocyanine thin films

The static optical recording properties of novel bromoboron trinitro-subphthalocyanine (BTN-SubPc) thin films were studied using a self-developed short-wavelength optical disk tester with high NA objective lens. High reflectivity contrast (>30%) was obtained at low writing power (8 mW) and short writing pulsewidth (200 ns) using the Ar⁺ laser (514.5 nm) irradiation. These results demonstrate that subphthalocyanine is not only qualified for red-light recording but also a promising candidate for the recording medium of a green-light DVD-R. The leading edge, just like the falling edge, of the dye’s absorption band can also be used to realize optical disk storage if an appropriate reflector was used. It provides a new clew for double-wavelength writing/reading and choosing short-wavelength recording materials.