衬底效应对LiTaO3薄膜制备的影响

用溶胶凝胶法在N型硅、P型硅、石英、铂、镍衬底上制备了钽酸锂(LiTaO3)薄膜,用XRD和SEM对钽酸锂薄膜性能参数进行了表征;发现掺杂少量环氧树脂能提高钽酸锂薄膜的均匀性,改善薄膜与衬底的粘附性;研究了衬底效应与薄膜厚度的关系,薄膜厚度超过0.2 μm,Ni衬底的XRD峰值强度几乎不再出现,说明衬底对薄膜初始结晶取向有重要影响;利用不同衬底上生长钽酸锂薄膜,XRD研究结果表明:N型硅、P型硅、石英衬底上只能制备多晶钽酸锂薄膜,铂衬底上制备的钽酸锂薄膜在(012)晶向有强大的择优取向性,镍衬底上制备的钽酸锂薄膜有更好的C轴择优取向性,C轴择优取向系数可达0.082。     

Effect of Mg-film thickness on the formation of semiconductor Mg2Si films prepared by resistive thermal evaporation method

Mg fi lms of various thicknesses were deposited on Si(111) substrates at room temperature by resistive thermal evaporation method, and then the Mg/Si samples were annealed at 40 ℃ for 4 h. The effects of Mg fi lm thickness on the formation and structure of Mg2Si fi lms were investigated. The results showed that the crystallization quality of Mg2Si fi lms was strongly infl uenced by the thickness of Mg fi lm. The XRD peak intensity of Mg2Si(220) gradually increased initially and then decreased with increasing Mg fi lm thickness. The XRD peak intensity of Mg2Si(220) reached its maximum when the Mg fi lm of 380 nm was used. The thickness of the Mg2Si fi lm annealed at 400 ℃ for 4 h was approximately 3 times of the Mg fi lm.     

Optimization of material structure of ploy-Si thin film based on Al induced crystallization

Based on Al induced crystallization (AIC) method, influences of different material structures on formation and characteristics of ploy-silicon thin films were studied and optimized. Al-Si films on glass with different structures (Si/Al/Glass, Al/Si/Glass, Si/Al/…/Si/Al/Glass) were deposited on glass substrates by sputtering method. All samples were annealed for MIC with varied time processes under 500℃ N2 environment. X-ray diffraction test and scanning electron microscope were adopted to characterize cryst...     

封闭式电子回旋共振等离子体低温沉积SrTiO3膜

在室温条件下，用封闭式电子回旋共振(MCECR)等离子体溅射方法沉积了SrTiO3(STO)膜．用Ar等离子体在Si基片上溅射的STO膜是非晶的，然而用Ar／O2等离子体在Pt／Ti／SiO2／Si上溅射的是充分结晶的STO膜．为了使非晶薄膜结晶，用电炉加热或28GHz微波辐射对非晶STO膜进行退火处理．采用微波辐射，使基片温度为573K时，在Si上的STO膜退火后的介电常数大约为260，这值近似等于块状STO材料的介电常数．由于微波辐射能够降低薄膜的退火温度和提高薄膜的电特性，因而被认为是非常有用的．     

Structure and Composition of Crystalline Carbon Nitride Films Synthesized by Microwave Plasma Chemical Vapor Deposition

Crystalline carbon nitride thin films were prepared on Si (100) substrates by a microwave plasma chemical vapor deposition method, using CH4/N2 as precursor gases. The surface morphologies of the carbon nitride films deposited on Si substrate at 830℃ are consisted of hexagonal crystalline rods. The effect of substrate temperature on the formation of carbon nitrides was investigated. X-ray photoelectron spectroscopy analysis indicated that the maximum value of N/C in atomic ratio in the films deposited at a substrate temperature of 830℃ is 1 .20, which is close to the stoichiometric value of C3N4. The X-ray diffraction pattern of the films deposited at 830℃ indicates no amorphous phase in the films, which are composed of β- and α-C3N4 phase containing an unidentified C-N phase. Fourier transform infrared spectroscopy supports the existence of C-N covalent bond.     

Structure and Composition of Crystalline Carbon Nitride Films Synthesized by Microwave Plasma Chemical Vapor Deposition

Crystalline carbon nitride thin films were prepared on Si (100) substrates by a microwave plasma chemical vapor deposition method, using CH4/N2 as precursor gases. The surface morphologies of the carbon nitride films deposited on Si substrate at 830℃ are consisted of hexagonal crystalline rods. The effect of substrate temperature on the formation of carbon nitrides was investigated. X-ray photoelectron spectroscopy analysis indicated that the maximum value of N/C in atomic ratio in the films deposited at a substrate temperature of 830℃ is 1.20, which is close to the stoichiometric value of C3N4. The X-ray diffraction pattern of the films deposited at 830℃ indicates no amorphous phase in the films, which are composed of - and -C3N4 phase containing an unidentified C-N phase. Fourier transform infrared spectroscopy supports the existence of C-N covalent bond.     

在LaNiO3衬底上（Pb,La）TiO3铁电薄膜的制备和研究

首先通过金属有机化合物热分解(MOD)法在Si(100)基片上制备出LaNiO3(LNO)薄膜,再通过溶胶-凝胶(sol-gel)法,在LNO/Si(100)衬底上制备出(PbxLa1-x)TiO3(PLT)铁电薄膜。经XRD分析表明,LNO薄膜具有(100)择优取向的类钙钛矿结构,PLT/LNO/Si薄膜具有四方相钙钛矿结构,同时以(100)择优取向。最后对薄膜的介电性和铁电性进行了测试,发现薄膜介电常数适中,铁电性良好。     

退火条件对ZnO薄膜结构和光学性能的影响

采用溶胶-凝胶法在单晶硅Si(100)衬底上制备了ZnO薄膜,研究了退火温度对ZnO结构和光学性能的影响。实验发现,退火可以明显地改善ZnO薄膜的结构和光学性能。随着退火温度的升高,ZnO薄膜的晶粒增大,同时在室温下观察到明显的紫外发光现象,其紫外PL谱峰值变强,并有红移现象。     

溶胶—凝胶工艺参数对PLT10薄膜显微结构的影响

研究了溶胶－凝胶工艺中溶胶陈化时间，热处理工艺条件和衬底材料对ＰＬＴ１０（Ｐｂ０．９Ｌａ０．１Ｔｉ０．９７５Ｏ３的简称）薄膜显微结构的影响。结果表明，在（１００）Ｓｉ单晶基片上制备的ＰＬＴ１０薄膜为钙钛矿结构的多晶陶瓷膜；在（１００）ＳｒＴｉＯ３衬底上制备的ＰＬＴ１０薄膜为（００１）择优取向的具有钙钛矿结构的单晶膜，（００１）择优取向度高达０．９５。溶胶陈化时间愈长，薄膜择优取向度愈高。热处理温度越高，ＰＬＴ１０薄膜钙钛矿结构发展越充分，薄膜晶粒尺寸越大。     

离子束增强沉积Al-N共掺杂ZnO薄膜的制备

用Al2O3粉体与ZnO粉体均匀混合,压制成溅射靶。在Si和SiO2/Si衬底上,用离子束增强沉积(IBED)方法对沉积 膜作Ar+/N+注入,制备Al-N共掺杂氧化锌薄膜(ANZO)。在氮气氛中作适当的退火,可以方便地获得取向单一、结构致 密、性能良好的共掺杂ZnO薄膜。探索用IBED方法在Si和SiO2衬底上制备优质掺杂薄膜的可能性。初步研究了ANZO共掺 杂薄膜的结构、电学和光学性能。     

Fabrication of GaN films through reactive reconstruction of magnetron sputtered ZnO/Ga_2O_3

1　INTRODUCTIONGallium nitride (GaN) is one of the most po tential semiconductors. GaN has a direct energyband gap of 3.4 eV at room temperature and highexternal photoluminescence quantum efficiency, aswell as a high excitonic binding energy of20 meV[1]. It is an ideal material for fabrication ofultraviolet(UV)/blue/green light emitting diodes(LEDs), laser diodes(LDs), UV detectors and de vices operating in high temperature, high frequen cy and high power co…     

PLZT薄膜的溅射沉积和热处理

用磁控射频溅射方法在不加热的硅衬底上沉积生长锆钛酸铅镧（PLZT）薄膜。由混浇法制备了两只氧化物靶材PLZT（5／65／35）和（9／65／35）。初生态薄膜主要是非晶态,所希望的钙钛矿相结构由后处理形成。研究了不同退火条件下焦绿石相和钙钛矿相的转变,实验表明氧气氛下由常规退火（LFA）和快速退火（RTA）可形成钙钛矿相PLZT薄膜。     

磁激励RF-PECVD法低温制备类金刚石薄膜及其特性

采用磁激励射频等离子体增强化学气相沉积(M-RF-PECVD)方法,室温下分别在玻璃和Si(100)衬底上制备类金刚石(DLC)薄膜,通过扫描电镜(SEM)、傅里叶红外光谱(FTIR)和Raman光谱对不同沉积条件下制备的薄膜进行表征。结果表明,在反应压强为30 Pa、入射功率为50 W、CH4/Ar=5/90、衬底温度为40℃的实验条件下,制备的含氢DLC薄膜表面平整、结构致密,膜基结合度良好,薄膜中以sp3键为主。     

衬底和热处理温度对ZnO薄膜的微观结构的影响

采用Sol-gel法,在普通载玻片和Si（100）上使用旋转涂覆技术制备了具有c轴择优取向生长的ZnO薄膜。利用XRD和SEM研究了衬底和热处理温度对ZnO薄膜的物相结构、表面形貌和（002）定向性的影响。结果表明,sol—gel旋涂法制备的ZnO薄膜为六角纤锌矿结构,玻璃衬底上生长的ZnO薄膜为多晶形态,Si（100）衬底表现出更优取向生长特性。随着热处理温度的升高,c轴择优取向程度逐渐增强,晶粒尺寸逐渐增大,ZnO的晶格参数先增加后减小。当温度在700℃时长出明显的柱状晶粒。     

在LaNiO_3衬底上（Pb,La）TiO_3铁电薄膜的制备和研究

首先通过金属有机化合物热分解（MOD）法在Si（100）基片上制备出LaNiO3（LNO）薄膜,再通过溶胶-凝胶（sol-gel）法,在LNO/Si（100）衬底上制备出（PbxLa1-x）TiO3（PLT）铁电薄膜。经XRD分析表明,LNO薄膜具有（100）择优取向的类钙钛矿结构,PLT/LNO/Si薄膜具有四方相钙钛矿结构,同时以（100）择优取向。最后对薄膜的介电性和铁电性进行了测试,发现薄膜介电常数适中,铁电性良好。     

Fabrication of GaN films through reactive reconstruction of magnetron sputtered ZnO／Ga2O3

A simple and easily operated technique was developed to fabricate GaN films. GaN films possessing hexagonal wurtzite structure were fabricated on Si(111) substrates with ZnO buffer layers through nitriding Ga2O3 films in the tube quartz furnace. ZnO buffer layers and Ga3O3 films were deposited on Si substrates in turn by using radio frequncy magnetron sputtering system before the nitriding process. The structure and composition of GaN films were studied by X-ray diffraction, selected area electron diffraction and Fourier transform infrared spectrophotometer. The morphologies of GaN films were studied by scanning electron microscopy. The results show that ZnO buffer layer improves the crystalline quality and the surface morphology of the films relative to the films grown directly on silicon substrates. The measurement result of room-temperature photoluminescence spectrum indicates that the photoluminescence peaks locate at 365 nm and 422 nm.     

电沉积法制备PbS薄膜的XRD分析

采用阴极恒电压法在ITO导电玻璃表面沉积了PbS薄膜,并用X-射线衍射仪(XRD)对薄膜的结构进行了表征,研究了沉积电压对薄膜的晶相组成的影响.结果表明:在U=3.0 V时,可制备出沿(111)晶面取向生长的立方相PbS薄膜;随沉积电压从3.0 V增加到4.5 V,薄膜的生长取向从(111)晶面变为(200)晶面,且PbS衍射峰的强度越来越强,到18 V时达到最强.     

Transport properties and microstructure of La0.7Sr0.3MnO3 nanocrystalline thin films grown by polymer-assisted chemical solution deposition

Perovskite-based materials can be widely used in the aerospace and transportation field. Perovskite manganese oxides La_0.7Sr_0.3MnO₃ (LSMO) thin films were grown on LaAlO₃ (100) and Si (100) single crystal substrates by the polymer-assisted chemical solution deposition (PACSD) method. Electronic transport behavior, microstructure, and magnetoresistance (MR) of LSMO thin films on different substrates were investigated. The resistance of LSMO films fabricated on LaAlO₃ substrates is smaller than that on the Si substrates. The magnetic field reduces resistance of LSMO films both on Si and LAO in the wide temperature region, when the insulator-metal transition temperature shifts to higher temperature. The low-field magnetoresistance of LSMO films on Si in low temperature range at 1 T is larger than that of LSMO films on LAO. However, the MR of LSMO film on LAO films at room-temperature is about 5.17 %. The thin films are smooth and dense with uniform nanocrystal size grain. These results demonstrate that PACSD is an effective technique for producing high quality LSMO films, which is significant to improve the magnetic properties and the application of automotive sensor.

     

Preparation of Poly (ethylene oxide)(PEO)Modified Tungsten Oxide Hybrid Films via Sol-Gel Processing

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｓｏｌ ｇｅｌｍｅｔｈｏｄｈａｓａｔｔｒａｃｔｅｄｓｐｅｃｉａｌｉｎｔｅｒｅｓｔｒｅ ｃｅｎｔｌｙｉｎｔｈｅｐｒｅｐａｒａｔｉｏｎｔｅｃｈｎｏｌｏｇｙｏｆｎｅｗｍａｔｅｒｉａｌｓｐｒｅ ｐａｒｅｄｂｙｃｏｍｂｉｎｉｎｇｏｒｇａｎｉｃａｎｄｉｎｏｒｇａｎｉｃｍａｔｅｒｉａｌｓ[1,2 ] .Ｔｈｅｓｏｌ ｇｅｌｐｒｏｃｅｓｓｉｓｂａｓｉｃａｌｌｙａｈｙｄｒｏｌｙｓｉｓａｎｄｃｏｎｄｅｎｓａ ｔｉｏｎｐｏｌｙｍｅｒｉｚａｔｉｏｎｒｅａｃｔｉｏｎｏｆｍｏｌｅｃｕｌａｒｐｒｅｃｕｒｓ…     

Effect of silver growth temperature on the contacts between Ag and ZnO thin films

Highly c-axis oriented ZnO thin films were deposited on Si substrates by the pulsed laser deposition (PLD) method. At different growth temperatures, 200 nm silver films as the contact metal were deposited on the ZnO thin films. The growth temperatures have great influence on the crystal quality of Ag films. Current-voltage characteristics were measured at room temperature. The Schottky contacts between Ag and ZnO thin films were successfully obtained when silver electrodes were deposited at 150°C and 200°C. Ohmic contacts were formed while the growth temperatures were lower than 150°C or higher than 200°C. After analysis, the forming of Ag/ZnO Schottky contacts was shown to be dependent on the appearance of the p-type inversion layer at the interface between Ag and ZnO layers.