Zn、Cu共掺杂TiO_2∶SiO_2薄膜材料的光学性能研究

用溶胶-凝胶法制得Zn、Cu共掺杂的TiO_2∶SiO_2凝胶,旋转法于玻璃基底涂膜,制得Zn、Cu共掺杂的TiO_2∶SiO_2薄膜,探讨了煅烧温度、煅烧时间及掺杂比例对其结构、形貌和性能的影响。采用XRD、FESEM、FTIR等测试技术对薄膜进行表征,并考察了其对甲基橙的光催化降解性能。XRD测试结果显示:薄膜样品的晶型为锐钛矿型,结晶良好。SEM谱图显示:薄膜微粒粒径小,分布均匀,表面平整、致密且无明显裂痕;紫外-可见光谱(UV-Vis)表明:Zn、Cu共掺杂的TiO_2∶SiO_2薄膜在紫外区和可见光区的吸光度明显增加,提高了对光的利用率;光催化性能测试表明:与纯相TiO_2对比,Zn、Cu共掺杂的TiO_2∶SiO_2薄膜对甲基橙的光催化降解率有较大提高,在600℃下焙烧2h的掺杂的量比为n(Ti)∶n(Si)∶n(Zn)∶n(Cu)=3∶2∶1.5∶4的薄膜样品光催化降解率最高。     

电子束退火法制备Li-N共掺杂多晶ZnO薄膜

为研究电子束退火对Li-N共掺杂Zn O薄膜性能的影响,首先利用溶胶-凝胶旋涂法在p型Si(111)衬底上制备Li-N共掺杂的Zn O前驱膜,然后用电子束对前驱膜进行退火。退火时,电子束加速电压10 k V,退火时间5 min,聚焦束流123 m A,束流为0.7~1.9 m A,最后得到Li-N共掺杂的Zn O薄膜。XRD谱分析表明,当束流高于1.5 m A之后,薄膜为六方Zn O和立方Zn O的混合多晶薄膜,且有金属Zn生成,导致薄膜有较强的绿光发射。SEM图片分析显示,薄膜的晶粒尺寸随束流增加而增大,当束流高于1.5 m A后,晶粒尺寸变化不大,约为60 nm。光致发光(PL)谱和激光拉曼谱的分析结果证实Li、N元素已掺入Zn O晶格中,PL谱中观察到Li元素掺杂引起的紫光发射,拉曼散射光谱中观察到N替代O位的缺陷振动模式。     

Zn掺杂的YBa2(Cu1-xZnx)3O7-δ(x=0, 0.01, 0.02)体系的反常霍尔效应

利用脉冲激光沉积(PLD)方法制备了c轴取向的高质量YBa2(Cu1-xZn)3O7-δ(x=0, 0.01, 0.02)外延薄膜.超导临界温度随Zn掺杂量增加而较快地下降,与单晶样品的结果相符.在强磁场下的输运测量发现YBa2(Cu1-xZn)3O7-δ系列样品在Tc附近均出现反常的Hall电阻率符号反向,但其Hall电导率σxy随磁场的变化关系与氧欠掺杂的YBa2Cu3O6.66存在很大差异,说明Zn掺杂和氧掺杂对混合态中的磁通涡旋性质的影响有显著不同.     

Co，Cu共掺杂ZnO薄膜的结构及发光特性

采用电子束蒸发沉积成膜工艺在单晶Si(111)衬底上制备出Co,Cu共掺杂的Zn0.85-xCo0.15CuxO(x=0,0.04,0.06)多晶膜。采用X射线衍射(XRD)研究了Co、Cu掺杂对其微结构的影响;室温下测量了Zn0.85-xCo0.15CuxO薄膜的光致发光谱,发现随着Cu掺杂量的增加,样品发光增强,当Cu掺杂x=0.06时,Zn0.85-xCo0.15CuxO薄膜的PL谱中出现了较强的双峰蓝光发射;分析了掺杂含量对其发光性能的影响,并对样品的发光机制进行了探讨,并推断出蓝光峰来源于电子由导带底到锌空位(VZn)能级的跃迁及锌填隙(Zni)能级到价带顶的跃迁。     

Zn,Cu共掺杂的TiO_2:SnO_2薄膜的制备及性能研究

用溶胶-凝胶法制得Zn,Cu共掺杂的TiO_2∶SnO_2凝胶,旋转法于玻璃基底镀膜,制备出Zn,Cu共掺杂的TiO_2∶SnO_2薄膜,探讨了掺杂比例、煅烧温度对其结构、形貌和性能的影响。采用XRD、FTIR、FESEM、PL等测试技术对薄膜进行表征,并考察了其对甲基橙的光催化降解性能。结果表明:600℃时,薄膜粒子的结晶度较高,粒径小,分布均匀,表面平整且无明显裂痕;紫外-可见光谱(UV-Vis)表明:该薄膜在可见光区和紫外区都有很强的吸收;光催化性能测试表明:与纯相TiO_2对比,该样品对甲基橙的光催化降解率有较大提高,在最佳掺杂量比为n(Ti)∶n(Sn)∶n(Zn)∶n(Cu)=10∶3∶1∶1时,光催化降解率最高。     

赝能隙导致的YBa2(Cu1－xMx)3O7-δ(M=Co,Zn)薄膜的输运性质异常

报道了两类典型元素替代的超导Y123相体系-YBa2(Cu1-xCox)3O7-δ(x=001,002)和YBa2(Cu1-yZny)3O7-δ(y=0005,0010)薄膜的电阻率温度特性(ρ(T))和Hall效应(RH(T)).研究表明,Co掺杂的Y123相体系十分类似于氧欠掺杂的情况,对Co掺杂的薄膜样品,由电阻率温度特性定义的赝能隙打开的温度T分别为193和225K.而Zn掺杂的样品没有观察到赝能隙打开对电阻率温度特性的影响.由Hall效应的测量和Hall角(cotθH)定义了另一个特征温度T0, 关键词： 赝能隙 Y123相 Hall效应     

Ni掺杂ZnO薄膜的结构与光学特性研究

使用射频磁控溅射法成功制备了不同掺杂浓度（0—7at.%）的ZnO:Ni薄膜.X射线衍射的θ-2θ和摇摆曲线扫描结果表明,5at.%Ni掺杂ZnO薄膜具有沿c轴方向最佳的择优取向生长特性,（002）衍射峰向大角度方向移动揭示了Ni杂质被掺入ZnO晶格中占据Zn位.ZnO:Ni薄膜具有较好的可见光透明特性,拟合发现薄膜的光学带隙随Ni掺杂量的增加由3.272 eV线性降低到3.253 eV.未掺杂薄膜在550 nm处呈现出一个绿色发光峰,掺入Ni杂质后薄膜主要表现了以430 nm为中心的蓝色发光,分析认为它们分别源于薄膜中O空位和Zn填隙缺陷发光. 关键词： ZnO:Ni薄膜 结构特性 光学带隙 光致发光     

Ti,Cu和Zn掺杂AlN纳米片电磁性质的第一性原理研究

采用基于密度泛函理论(DFT)的全势线性缀加平面波法(FP-LAPW)研究了过渡金属Ti,Cu,Zn掺杂Al N纳米片的电子结构、磁性和稳定性.结果表明,Ti,Cu,Zn单掺杂均表现出半金属铁磁性,磁性主要是由于杂质原子的3d态与近邻N原子的2p态的轨道杂化.形成能的计算结果表明Ti掺杂Al N体系相对Cu和Zn掺杂结构更稳定.因此,相比于Cu和Zn,Ti掺杂Al N纳米片更适合用来制作稀磁半导体.     

Co与Cu掺杂ZnO薄膜的制备与光致发光研究

采用溶胶-凝胶旋涂法在玻璃衬底上制备了Co, Cu单掺杂及Co,Cu共掺杂ZnO薄膜.用金相显微镜观察了Co与Cu掺杂对ZnO薄膜形貌的影响.X射线衍射（XRD）研究揭示所有ZnO薄膜样品都存在（002）择优取向,在Cu单掺的ZnO薄膜中晶粒尺寸最大.对所有样品的室温光致发光测量都观察到较强的蓝光双峰发射和较弱的绿光发射,其中长波长的蓝光峰和绿光峰都能够通过掺杂进行控制.对不同掺杂源的ZnO薄膜发光性能进行了分析,认为蓝光峰来源于电子由导带底到锌空位能级的跃迁及锌填隙到价带顶的跃迁,绿光峰是由于掺杂造成的 关键词： ZnO薄膜 溶胶-凝胶 Co Cu掺杂 光致发光     

内在缺陷与Cu掺杂共存对ZnO电磁光学性质影响的第一性原理研究

采用基于自旋密度泛函理论的平面波超软赝势方法,研究了Cu掺杂ZnO (简称Cu_(Zn))与内在缺陷共存对ZnO电磁光性质的影响.结果表明,Cu是以替位受主的形式掺入的;制备条件对Cu_(Zn)及内在缺陷的形成起至关重要的作用,富氧条件下Cu掺杂有利于内在缺陷的形成,且Cu_(Zn)-O_i最易形成;相反在缺氧条件下,Cu掺杂不利于内在缺陷的形成.替位Cu的3d电子在价带顶形成未占据受主能级,产生p导电类型.与Cu_(Zn)体系相比,Cu_(Zn)-V_O体系中载流子浓度降低,导电性变差;Cu_(Zn)-V_(Zn)体系中载流子浓度几乎不变,对导电性没影响;Cu_(Zn)-O_i体系中载流子浓度升高,导电性增强.纯ZnO体系无磁性;而Cu掺杂ZnO体系,与Cu原子相连的O原子,电负性越小,键长越短,对磁矩贡献越大;Cu_(Zn)与Cu_(Zn)-O_i体系中的磁矩主要是Cu的3d电子与Z轴上O的2p电子耦合产生的;Cu_(Zn)中存在空位缺陷(V_O,V_(Zn))时,磁矩主要是Cu 3d电子与XY平面内O的2p电子强烈耦合所致;Cu_(Zn)中存在V_(Zn)时,磁性还包含V_(Zn)周围0(5, 6)号原子2p轨道自旋极化的贡献;所有体系中Zn原子自旋对称,不产生磁性.Cu_(Zn)-V_(Zn)和Cu_(Zn)-O_i缺陷能态中,深能级中产生的诱导态是0-0 2s电子相互作用产生的.Cu_(Zn)模型的光学带隙减小,导致吸收边红移;Cu_(Zn)-V_(Zn)模型中吸收和反射都增强,使得透射率降低.     

纳米ZnO薄膜可见发射机制研究

利用溶胶－凝胶法 （Sol-Gel）制备了纳米ZnO薄膜，获得了高强的近紫外发射室温下测量了样品的光致发光谱(PL )、吸收谱(ABS)、X射线衍射谱(XRD).X射线衍射(XRD)的结果表明：纳米ZnO薄膜呈多晶态，具有六角纤锌矿结构和良好的C轴取向；发现随退火温度升高，（002）衍射峰强度显著增强，衍射峰的半高宽（FWHM）减小、纳米颗粒的粒径增大.由吸收谱(ABS)给出了样品室温下带隙宽度为3.30 eV.在PL谱中观察到二个荧光发射带，一个是中心波长位于392 nm附近强而尖的紫带，另一个是519 nm附近弱而宽的绿带研究了不同退火温度样品的光致发光峰值强度的变化关系，发现随退火温度升高，紫带峰值强度增强、绿带峰值强度减弱，均近似呈线性变化.证实了纳米ZnO薄膜绿光发射主要来自氧空位(Vo)形成的浅施主能级与锌空位(VZn)形成的浅受主能级之间的复合，或氧空位(Vo)形成的深施主能级上的电子至价带顶的跃迁；紫带来自于导带中的电子与价带中的空位形成的激子复合.     

Comparison of the optical properties of undoped and Ga-doped ZnO thin films deposited using RF magnetron sputtering at room temperature

The optical properties of undoped zinc oxide (ZnO) thin films of various thicknesses were compared with those of Ga-doped (GZO) thin films. Transparent, high-quality undoped ZnO and GZO films were deposited successfully using radio-frequency (RF) sputtering at room temperature. The films were polycrystalline with a hexagonal structure and a strongly preferred orientation along the c-axis. The films had an average optical transmission >85% in the visible part of the electromagnetic spectrum. The undoped ZnO thin films were more transparent than the GZO thin films. In the photoluminescence (PL) spectrum, ZnO film has higher quality than GZO as a result of decrease in the green emission intensity.     

Effect of dopants on the structural,optical and electrical properties of sol–gel derived ZnO semiconductor thin films

Undoped, Ga-, In-, Zr-, and Sn-doped ZnO transparent semiconductor thin films were deposited on alkali-free glasses by sol–gel method. 2-methoxyethanol (2-ME) and diethanolamine (DEA) were chosen as a solvent and a stabilizer, respectively. The doping concentration was maintained at 2 at.% in the impurity doping precursor solutions. The effects of different dopants on the structural, optical, and electrical properties of ZnO thin films were investigated. XRD results show that all annealed ZnO-based thin films had a hexagonal (wurtzite) structure. ZnO thin films doped with impurity elements obviously improved the surface flatness and enhanced the optical transmittance. All impurity doped ZnO thin films showed high transparency in the visible range (>91%). The Ga- and In- doped ZnO thin films exhibited higher Hall mobility and lower resistivity than did the undoped ZnO thin film.     

不同退火温度下氧化锌薄膜可见发光与n型导电研究

采用脉冲激光沉积法在蓝宝石衬底上制备出可见光发光良好的氧化锌薄膜, 在不同的温度下进行了后退火处理. 随着退火温度的升高, 薄膜的可见光发光发生了显著改变, 载流子浓度、迁移率、电阻率也呈现出一定的变化规律. 结合 X射线衍射、扫描电子显微镜、光致发光谱及霍尔测量, 探讨了本征氧化锌薄膜可见光发光的发射机理, 并分析了其 n型导电的原因. 关键词： 氧化锌薄膜 可见光发光 n型导电     

Structural and optical properties of ZnO thin films on (111) CaF2 substrates grown by magnetron sputtering

ZnO thin films were grown on (111) CaF₂ substrates by magnetron sputtering at room temperature. Structural and optical properties of the ZnO thin films were studied. XRD analysis showed that the ZnO thin films had the (002) preferential orientation. The transmittance of ZnO thin films was over 80% in the visible range. The optical band gap of the ZnO thin films was 3.26 eV. The optical constants (n,k)$(n,k)$ of the ZnO thin films in the wavelength range 300–1000 nm were obtained by infrared spectroscopic ellipsometry measurement. PL spectra of ZnO thin films showed strong UV near-band-edge emission peak at 376.5 nm and weak visible red emission at 643.49 nm using He–Cd laser as the light source, using a synchrotron radiation light source PL spectra showed three emission peak at 320 nm, 410 nm and 542 nm respectively.     

ZnO:Fe薄膜制备、光学与电学性质研究

用双靶磁控溅射设备制备了ZnO:Fe薄膜。分析了铁靶溅射功率对薄膜的光学及电学性质的影响。X射线衍射(XRD)和原子力显微镜(AFM)图像表明:ZnO:Fe薄膜为六角纤锌矿结构,且具有非常好的沿垂直于衬底的c轴择优取向。当铁靶功率小于250W时,沉积速率随铁靶功率的增加而增加。随着铁靶功率的增加,透射光谱的吸收边有微弱蓝移,透过率在可见光区超过75%。掺铁后薄膜的电阻率只有10-2Ω.cm,远小于纯氧化锌的电阻率。通过实验得到ZnO:Fe薄膜的最佳制备条件。     

热处理参数对溶胶-凝胶法制备氧化锌薄膜特性的影响

采用溶胶-凝胶旋涂法在Si(111)衬底上生长了ZnO薄膜，并用荧光光谱、原子力显微镜和XRD对ZnO薄膜样品进行了分析.结果表明，溶胶-凝胶旋涂法制备的ZnO薄膜为纤锌矿结构，其c轴取向程度与热处理温度有很大的关系.当热处理温度小于550℃时，氧化锌薄膜在室温下均有较强的紫外带边发射峰，而可见波段的发射很弱；当热处理温度高于550℃时，可见波段发射明显增强.对经过不同时间热处理的ZnO薄膜样品分析表明，氧化锌薄膜的荧光特性及表面形貌与热处理时间也有很大关系，时间过短可见波段的发射较强，但时间过长会导致晶 关键词： ZnO薄膜 光致发光     

Effect of excimer laser annealing on the properties of ZnO thin film prepared by sol-gel method

Pristine ZnO thin films have been deposited with zinc acetate [Zn(CH₃COO)₂], mono-ethanolamine (stabilizer), and isopropanol solutions by sol-gel method. After deposition, pristine ZnO thin films have been irradiated by excimer laser (λ = 248, KrF) source with energy density of 50 mJ/cm² for 30 sec. The effect of excimer laser annealing on the optical and structural properties of ZnO thin films are investigated by photoluminescence and field emission scanning electron microscope. As-grown ZnO thin films show a huge peak of visible region and a wide full width at half maximum (FWHM) of UV region due to low quality with amorphous ZnO thin films. After KrF excimer laser annealing, ZnO thin films show intense near-band-edge (NBE) emission and weak deep-level emission. The optically improved pristine ZnO thin films have demonstrated that excimer laser annealing is novel treatment process at room temperature.     

Characteristics of ZnO:In thin films prepared by RF magnetron sputtering

In-doped ZnO (ZnO:In) transparent conductive thin films were deposited on glass substrates by RF magnetron sputtering. The effect of substrate temperature on the structural, electrical and optical properties of the ZnO:In thin films was investigated. It was found that higher temperature improves the crystallinity of the films and promotes In substitution easily. ZnO:In thin films with the best crystal quality were fabricated at 300 °C, which exhibit a larger grain size of 29 nm and small tensile strain of 0.9%. The transmittance of all the films was revealed to be over 85% in the visible range independence of the substrate temperatures and the lowest resistivity of ZnO:In thin films is 2.4×10⁻³ Ω cm.     

Characteristics of ZnO:In thin films prepared by RF magnetron sputtering

In-doped ZnO (ZnO:In) transparent conductive thin films were deposited on glass substrates by RF magnetron sputtering. The effect of substrate temperature on the structural, electrical and optical properties of the ZnO:In thin films was investigated. It was found that higher temperature improves the crystallinity of the films and promotes In substitution easily. ZnO:In thin films with the best crystal quality were fabricated at 300 °C, which exhibit a larger grain size of 29 nm and small tensile strain of 0.9%. The transmittance of all the films was revealed to be over 85% in the visible range independence of the substrate temperatures and the lowest resistivity of ZnO:In thin films is 2.4×10⁻³ Ω cm.