Si(100)衬底上PLD法制备高取向度AlN薄膜

采用脉冲激光沉积法(PLD),以KrF准分子为脉冲激光源,Si(100)为衬底,同时引 入缓冲层TiN和Ti_0.8Al_0.2N,制备了结晶质量优异的A1N薄膜,X射线衍射(XRD)及反射 式高能电子衍射(RHEED)分析表明A1N薄膜呈(001)取向、二维层状生长.研究发现,薄膜 的生长模式依赖于缓冲层种类,直接在Si衬底上或MgO／Si衬底上的A1N薄膜呈三维岛状生 长;而同时引入缓冲层TiN和Ti_0.8Al_0.2N时,A1N薄膜呈二维层状生长.此外,激光能量密 度大小对A1N薄膜的结晶性有显著的影响,激光能量密度过大,薄膜表面粗糙,有颗粒状沉积 物生成.在氮气气氛中沉积,能使薄膜的取向由(001)改变为(100).     

STO/YBCO薄膜的制备及介电性能研究

采用脉冲激光沉积技术,在(100)LaAlO3单晶基片上生长SrTiO3/Y1Ba2Cu3O7-x(STO/YBCO)多层薄膜。XRD分析表明:YBCO薄膜和STO薄膜均为C轴取向,STO(002)/YBCO(006)衍射峰摇摆曲线半高宽为0.73°。AFM分析表明,STO/YBCO多层薄膜表面平整、均匀,在77K,100kHz的测试条件下,STO薄膜介电损耗tgδ<10-2,在53.6kV/cm电场作用下,介电常数的相对变化为38%。     

沉积条件对LiCoO2薄膜结构与形貌的影响

采用脉冲激光沉积(PLD)方法制备了LiCoO2薄膜,并研究了沉积条件对PLD生长的LiCoO2薄膜结构和形貌的影响.结果表明,适当减少激光功率可以有效降低LiCoO2薄膜表面粗糙度;采用在400℃原位退火可以得到层状结构的LiCoO2薄膜,而在一定范围内提高原位退火温度和升高氧气偏压可以提高层状结构的LiCoO2薄膜的结晶度.本实验中最优工艺制备的LiCoO2薄膜具有较好电化学可逆性,首次放电容量为36μAh/(μm·cm2),循环效率为94.44%.     

GaN基半导体上BiFeO_3薄膜的生长与性能研究

采用脉冲激光沉积法在(0001)取向的GaN以及AlGaN/GaN调制掺杂结构上制备了(111)取向的BiFeO3(BFO)薄膜。首先在导电氧化物SrRuO3和TiO2缓冲层包覆的GaN上制备了BFO薄膜,分析了在GaN上生长的BFO薄膜的面外取向、外延关系、表面形貌以及电学性能等性质。然后,在AlGaN/GaN调制掺杂结构上采用TiO2缓冲层生长了BFO薄膜,并采用光刻工艺分别在AlGaN表面制备Ti/Al/Ti/Au欧姆电极和BFO表面制备Ni/Au肖特基电极以形成二极管结构。C-V测试表明,由于BFO铁电薄膜极化的作用,BFO/TiO2/AlGaN/GaN结构具有1 V左右的逆时针窗口。     

PLD制备钛酸铅薄膜过程的RHEED分析

本文采用反射式高能电子衍射(RHEED)监测脉冲激光沉积法制备钛酸铅薄膜过程.根据PbTiO3/MgO(001)薄膜、PbTiO3/Si(100)薄膜生长过程中RHEED强度的时间演变,分析基片对薄膜生长模式的影响.并且观测不同生长时刻的RHEED强度的空间分布,讨论生长过程中薄膜表面的台阶尺寸变化.另外,比较在不同氧分压下沉积的钛酸铅薄膜表面的RHEED图案,发现氧气将改变薄膜的微结构,提高薄膜的结晶性.     

(Bi_(0.8)La_(0.2)FeO_3)_(0.8)-(NiFe_2O_4)_(0.2)材料的合成及薄膜多铁性能

研究了Bi0.8La0.2FeO3单相陶瓷的合成,并采用脉冲激光沉积法,在SrTiO3(100)(STO)基底上,以La0.7Sr0.3MnO3(LSMO)为缓冲层,制备了(Bi0.8La0.2FeO3)0.8-(NiFe2O4)0.2(BLFO-NFO)多铁薄膜。通过X射线衍射仪和场发射扫描电子显微镜确定了BLFO-NFO多铁薄膜的显微结构,通过标准铁电测试系统(RT-66A)和振动样品磁强计(VSM)分别测试了BLFO-NFO多铁薄膜的铁电性能和铁磁性能。研究发现:BLFO-NFO多铁薄膜沿(100)方向外延生长,晶粒为70nm,它具有明显的电滞回线和磁滞回线。     

BST类铁电薄膜的最低晶化温度和自装生长研究

利用激光分子束外延技术(LMBE)在Si(111)、SrTiO3(100)单晶基片上在(10-5pa)高真空环境中外延生长SrTiO3(STO)、BaTiO3(BTO)、Ba0.6Sr0.4TiO3(BST)铁电薄膜.通过反射高能电子衍射(RHEED)实时监测薄膜生长,并结合原子力显微镜(AFM)分析薄膜的生长模式.根据RHEED衍射强度振荡曲线及衍射图样的变化确定动态和静态最低晶化温度,发现STO、BTO、BST三种铁电薄膜可以分别在280℃、330℃、340℃的低温下实现外延层状生长.当保持BTO(110)/Si(111)层状生长,逐渐降低沉积速率时,发现这种层状模式中每层高度是由整数倍单胞堆积而成,并且随着沉积速率从0.017nm/s降低到0.005nm/s时,每层高度由9降低到1个BTO单胞构成,这对由ABO3钙钛矿材料自组装形成纳米结构具有重要意义.     

脉冲激光沉积制备外延Ni_(0.8)Zn_(0.2)Fe_2O_4薄膜的应变与磁性能研究

用脉冲激光沉积设备,分别在SrTiO3(001)(STO)和MgO(001)基片上外延生长了单层Ni0.8Zn0.2Fe2O4(NZF)薄膜。经X射线衍射分析,在STO和MgO基片上制备的NZF薄膜均为单一c取向的外延薄膜,由PHI扫描可知薄膜均为四重对称结构。由NZF薄膜的倒易空间图可以计算得到在STO和MgO基片上应变分别为0.0704和-0.0124。分别对不同基片上的NZF薄膜进行磁强计测量可得,在STO基片上沉积的NZF薄膜的面内和面外饱和磁化强度分别为269.6和224.78 emu/cm3,面内和面外的矫顽场分别为2.68×104和4.78×104A/m,在MgO基片上沉积的NZF薄膜的面内和面外饱和磁化强度分别为219.11和180.75 emu/cm3,面内和面外的矫顽场分别为3.46×104和5.32×104A/m。     

脉冲激光沉积溅射工艺对CIGS薄膜成分和结构的影响

采用脉冲激光沉积溅射法在玻璃衬底上制备Cu-In-Ga预制膜,后经硒化、退火处理,得到CIGS薄膜。采用X射线衍射仪表征了薄膜的晶体结构,采用扫描电子显微镜和能量散射谱观察和分析了薄膜的表面形貌和元素成分,采用光电子能谱分析了薄膜表面的化学价态。结果表明,预制膜采用玻璃/In/Cu-Ga的叠层顺序且溅射脉冲数为In靶60000,Cu-Ga靶50000的溅射方式,可制备出沿(112)晶向择优生长的CIGS薄膜。     

高分子辅助沉积法制备LaNiO3外延导电薄膜

近年来LaNiO₃(LNO)作为铁电超晶格、超导异质结和催化剂材料引起了广泛关注。本研究采用简便、低成本的高分子辅助沉积法(Polymer Assisted Deposition, PAD), 在(001)取向的SrTiO₃(STO)单晶衬底上制备了导电性能优异的LNO外延薄膜, 并对其进行各种结构和电学表征。摇摆曲线半高宽为0.38°, 表明LNO薄膜结晶度良好。高分辨XRD的φ扫描进一步证实LNO薄膜在STO衬底上异质外延生长。原位变温XRD测试进一步表征了LNO薄膜的外延生长过程。结果表明, 聚合物分解之后金属阳离子在单晶基体上有序释放并外延结晶。XPS结果表明, 采用PAD制备的LaNiO₃薄膜不存在氧空位。薄膜表面光滑, 粗糙度为0.67 nm。在10~300 K温度区间内的变温电阻率表明LNO薄膜具有良好的导电性能。上述结果表明：PAD制备的LaNiO₃薄膜具有较好的综合性能, PAD在制备外延功能薄膜材料方面具有很大的潜力。     

Si(100)衬底上激光分子束外延制备高质量TiN薄膜

采用激光分子束外延(LMBE)技术在Si(100)上制备了高质量的TiN薄膜.对N2分压和激光脉冲能量对TiN薄膜晶体结构、生长模式和表面形貌影响的研究表明,TiN单晶薄膜呈(200)择优取向,在N2分压为10-1 Pa时,薄膜的结晶度高且表面平整致密.随着N2分压的增加,TiN(200)衍射峰向低角度移动.激光脉冲能...     

直流磁控反应溅射制备IrO2薄膜

为研究氧化铱（ＩｒＯ２）对ＰＺＴ铁电薄膜疲性能的影响。利用直流（ＤＣ）磁控反应溅射（ｓｐｕｔｔｅｒｉｎｇ）工艺成功地在ＳｉＯ２／Ｓｉ（１００）衬底上制得了高度取向的ＩｒＯ２薄膜,并在其上制成ＰＺＴ铁电薄膜,讨论了溅射参数（溅射功率、Ａｒ／Ｏ２比、衬底温度）以及退火条件对氧化铱薄膜的结晶,取向和形态的影响。     

Fe2O3/TiO2和ZnO/TiO3纳米颗粒薄膜的亲水性能和光催化性能的研究

采用溶胶—凝胶法在玻璃上制备了锐钛矿型TiO2和过渡金属铁、锌离子掺杂的TiO2薄膜，并通过XRD、XPS、AFM表征了合成的薄膜．结果表明铁和锌离子掺入后，TiO2薄膜变的更加致密．铁离子和锌离子分别以Fe2O3和ZnO的形式存在．在紫外光照射下，TiO2薄膜表现明显的亲水性．金属离子掺杂的TiO2薄膜，亲水性能明显增强．铁离子掺入对光催化降解甲基橙有一定的抑制作用；少量的锌离子掺入对光催化降解甲基橙有促进作用，锌离子掺入量增大后，效果并不明显．     

Effect of In incorporation on the structural, electrical, and gas sensing properties of ZnO films

In this paper, we report some comparative results on the structural, electrical, and gas sensing properties of undoped, In-doped ZnO, and ZnO–In₂O₃ thin films, respectively. The oxide films were obtained by thermal oxidation (flash oxidation) of metallic films, deposited by thermal evaporation under vacuum. X-ray diffraction patterns reveal that oxidized films are polycrystalline, the crystallites being preferentially oriented with (002) planes parallel with the substrate. It was observed that the films’ morphology, investigated by atomic force microscopy and scanning electron microscopy, is influenced by the In amount. The temperature dependence of electrical conductivity was studied and obtained results indicate that In-doped ZnO and ZnO–In₂O₃ films exhibit an enhancement of electrical conductivity with four orders of magnitude by comparison with undoped ZnO film. Gas sensitivity measurements were performed for four different gases (ammonia, methane, acetone, and ethanol), and it was observed that all investigated films are more sensitive to ammonia. Also, it was observed that gas sensitivity is visibly increased for In-doped ZnO and ZnO–In₂O₃ samples by comparison with undoped ZnO film.     

锂掺杂MoO3薄膜的制备及电色性能的研究

采用过氧化氢溶胶－凝胶法成功地在室温下制备了纯的ＭｏＯ３和锂掺杂的ＭｏＯ３薄膜,通过ＴＧ－ＤＴＡ热分析、ＦＴＩＲ红外光谱分析、循环伏安和光学特性的测试,研究了薄膜成膜过程中的结构墨迹过程和薄膜的电化学性能及电变色性能,结果表明通过Ｌｉ＾＋掺杂,ＭｏＯ３溶胶的稳定性和ＭｏＯ３薄膜的电化学循环稳定性都有了较大的提高,且掺杂锂的ＭｏＯ３薄膜仍具有良好的变色性能。     

超亲水TiO2/SiO2复合薄膜的制备与表征

通过sol-gel工艺在普通钠钙玻璃表面制备了均匀透明的TiO2/SiO2复合薄膜,实验结果表明：在TiO2薄膜中添加SiO2,可以抑制薄膜中TiO2晶粒的长大,同时薄膜表面的羟基含量增加,水在复合薄膜表面的润湿角下降,亲水能力增强,当SiO2含量为10－20mol%时获得了润湿角为0度的超亲水性薄膜。     

Microstructural and optical properties of Ga-doped ZnO semiconductor thin films prepared by sol-gel process

Transparent thin films of Ga-doped ZnO (GZO), with Ga dopant levels that varied from 0 to 7 at.%, were deposited onto alkali-free glass substrates by a sol-gel process. Each spin-coated film was preheated at 300 °C for 10 min, and then annealed at 500 °C for 1 h under air ambiance. The effects of Ga dopant concentrations on crystallinity levels, microstructures, optical properties, and electrical resistivities of these ZnO thin films were systematically investigated. Photoluminescence spectra of GZO thin films were examined at room temperature. XRD results revealed that the undoped ZnO thin films exhibited a preferred orientation along the (002) plane and that the ZnO thin films doped with Ga showed degraded crystallinity. Experimental results also showed that Ga doping of ZnO thin films could markedly decrease surface roughness, improve transparency in the visible range, and produce finer microstructures than those of undoped ZnO thin films. The most promising films for transparent thin film transistor (TTFT) application produced in this study, were the 3 and 5 at.% Ga-doped ZnO thin films, both of which exhibited an average transmittance of 90.6% and an RMS roughness value of about 2.0 nm.     

Comparative study of zinc oxide and aluminum doped zinc oxide transparent thin films grown by direct current magnetron sputtering

Pure and aluminum (Al) doped zinc oxide (ZnO and ZAO) thin films have been grown using direct current (dc) magnetron sputtering from pure metallic Zn and ceramic ZnO targets, as well as from Al-doped metallic ZnAl2at.% and ceramic ZnAl2at.%O targets at room temperature (RT). The effects of target composition on the film's surface topology, crystallinity, and optical transmission have been investigated for various oxygen partial pressures in the sputtering atmosphere. It has been shown that Al-doped ZnO films sputtered from either metallic or ceramic targets exhibit different surface morphology than the undoped ZnO films, while their preferential crystalline growth orientation revealed by X-ray diffraction remains always the (002). More significantly, Al-doping leads to a larger increase of the optical transmission and energy gap (E_g) of the metallic than of the ceramic target prepared films.     

Y2O3-SnO2常温气敏薄膜的Sol-Gel制备及性能研究

以无机盐ＳnCl2.2H2O,Y(NO3)3.6H2O为原料,无水乙醇为溶剂,采用溶胶－凝胶工艺制备了Ｙ２Ｏ３掺杂的ＳnO２薄膜,采用差热－失重分析研究了Ｙ２Ｏ３掺杂的ＳnO2干凝胶粉末的热分解、晶体过程。研究了Ｙ２Ｏ３－ＳnO2薄膜的电学和气敏性能,从实验中得到了Ｙ２Ｏ３掺杂份量对ＳnO2薄膜电学及气敏性能的影响。实验表明Ｙ２Ｏ３掺杂的ＳnO2薄膜在常温下对ＮＯx具有较好的灵敏度的选择性,并具有较好的响应恢复性能,在常温下对Ｈ２Ｓ气体也具有一定的灵敏度。