MgxZn1-xO/Au/MgxZn1-xO夹层透明导电薄膜的制备及光电性质研究

采用操作简单的溶胶-凝胶法和射频磁控溅射法在石英衬底上分别制备了MgxZn1-xO薄膜和MgxZn1-xO/Au/MgxZn1-xO夹层结构的透明导电薄膜并对样品进行退火处理。利用紫外-可见分光光度计、X射线衍射仪、光致发光、霍尔效应测试对在不同退火温度下薄膜的晶体结构、光学和电学性质进行表征分析,并研究退火温度对其影响。测试结果表明:所制备的薄膜样品均具有良好的c轴(c-axis)取向并呈现出六角纤锌矿结构。Mg组分的增加使得ZnO基薄膜的光学带隙逐渐增大,PL发光谱和吸收光谱的谱线出现了明显的蓝移现象,但薄膜的电学特性有所降低。而在MgxZn1-xO/Au/MgxZn1-xO夹层结构的薄膜样品中,Au夹层的存在使薄膜的光学性质变差,在紫外区域透光率约为60%。但薄膜的电学性质得到明显改善,相比MgxZn1-xO薄膜,其电阻率和迁移率显著提高。此外通过高温退火处理可以有效提高所制备薄膜的晶体质量,进一步提高样品电学特性,其中经过500℃退火后的薄膜迁移率达到了40.9cm2·Vs-1,电阻率为0.005 7Ω·cm。但随着退火温度的进一步升高,薄膜晶体尺寸从25.1nm增大到32.4nm,从而降低了该薄膜的迁移率。因此该夹层结构的MgxZn1-xO/Au/MgxZn1-xO薄膜对于促进ZnO基透明导电薄膜在深紫外光学器件中的应用有重要作用。     

热处理对ZnO/Au薄膜结构和压电特性的影响（英文）

通过射频磁控溅射在氧化硅片表面沉积ZnO/Au薄膜,并通过不同的热处理方式对薄膜进行退火。为了研究退火对ZnO/Au薄膜结构和压电特性的影响,采用X射线衍射分析(XRD)、光学显微镜、场发射扫面电镜(FESEM)和压电力分析仪对薄膜退火前后的材料特性进行了分析。研究发现,热处理能够改善ZnO/Au薄膜的结晶质量。特别是在氮气保护氛围下慢速退火后,薄膜结晶质量有明显改善。但是,热处理导致了薄膜的压电系数d33和d31降低。分析认为,热处理过程中Au原子在ZnO中的易迁移特性破坏了ZnO/Au薄膜的压电性能。     

热处理对ZnO/Au薄膜结构和压电特性的影响

通过射频磁控溅射在氧化硅片表面沉积ZnO/Au薄膜,并通过不同的热处理方式对薄膜进行退火。为了研究退火对ZnO/Au薄膜结构和压电特性的影响,采用X射线衍射分析（XRD）、光学显微镜、场发射扫面电镜（FESEM）和压电力分析仪对薄膜退火前后的材料特性进行了分析。研究发现,热处理能够改善ZnO/Au薄膜的结晶质量。特别是在氮气保护氛围下慢速退火后,薄膜结晶质量有明显改善。但是,热处理导致了薄膜的压电系数d33和d31降低。分析认为,热处理过程中Au原子在ZnO中的易迁移特性破坏了ZnO/Au薄膜的压电性能。     

以Au为缓冲层在Si衬底上生长ZnO薄膜

采用化学气相沉积(CVD)方法在Si(001)衬底上分别制备了有金属Au缓冲层以及无Au缓冲层的ZnO薄膜。其中Au缓冲层在物理气相沉积(PVD)设备中蒸发,厚度大约为300nm。有Au缓冲层的ZnO薄膜晶体质量比直接在Si衬底上生长有了显著提高。利用X射线衍射(XRD)研究了所生长ZnO薄膜的结晶质量,有Au缓冲层的ZnO薄膜虽然仍为多晶,但显示出明显的择优取向。用光学显微镜研究了ZnO薄膜的表面特征,金属Au缓冲层显著地提高了在Si衬底上生长的ZnO薄膜的晶粒尺寸及平整度。同时利用室温光致发光(PL)谱研究了ZnO薄膜的光学性质,并分析了有Au缓冲层的ZnO薄膜NEB发光峰强度反而弱的可能原因。     

ZnO/Zn界面对纳米ZnO薄膜光学性质的影响

采用氧等离子体辅助电子束蒸发金属Zn后低温退火的方法制备纳米ZnO薄膜。利用X射线衍射(XRD)谱、拉曼(Raman)谱、X射线光电子能谱(XPS)以及光致发光(PL)谱等手段,分析了退火温度及ZnO/Zn界面对样品的结构和发光性质的影响。Raman结果表明随着退火温度的升高,界面模式(Es)振动减弱并向低波数方向移动。当退火温度为400℃时,界面振动消失,Zn全部转化成具有六方纤锌矿结构的ZnO,得到化学配比的纳米ZnO薄膜。PL谱表明,经400℃退火处理的样品紫外发射最强,发光性质最好。     

N掺杂ZnO薄膜的接触特性

氧化锌(ZnO)是一种直接带隙半导体材料,室温下带隙为3.37eV,激子束缚能为60meV。ZnO因其优越的光电特性在高亮度蓝紫光发光器件、紫外探测器件和短波长激子型激光器等方面具有广阔的应用前景。而要实现大功率的光电器件,稳定可靠的欧姆接触是必需的。研究了氮气氛条件下,不同温度快速退火对氮掺杂ZnO样品的电学性质以及Ni/Au与其接触特性的影响。原生样品表现为弱的肖特基接触,适当温度退火后,由肖特基转成了欧姆接触,650℃退火后得到最小比接触电阻率8×10-4Ω·cm2。霍尔测量表明550℃快速退火后,样品的导电类型由p型转变成了n型。采用AES和GXRD分别研究了不同退火温度下Au、Ni、Zn、O的深度分布变化及退火后所生成的合金相。实验结果表明,退火所导致的薄膜电学性质的变化以及界面态和表面态的增加是接触特性变化的原因。     

石英衬底上Au缓冲层对ZnO薄膜微结构的影响

采用单源化学气相沉积(SSCVD)法,在石英衬底上以Au为缓冲层,Zn4(OH)2(O2CCH3)6.2H2O为固相源制备ZnO薄膜。SEM和XRD测试ZnO薄膜的微结构,结果表明:相对于SiO2衬底上生长的ZnO薄膜,Au/SiO2衬底上生长的ZnO薄膜具有较好的结晶质量和表面平整度;对制备ZnO薄膜的衬底温度进行了工艺优化,结果表明:500℃时制备的ZnO薄膜颗粒大小均匀,结晶质量较好;通过荧光光谱仪对Au/SiO2衬底上的ZnO薄膜进行光致发光(PL)谱测试,ZnO薄膜在400nm出现紫光发射峰,而没有出现与缺陷相关的深能级发射峰,表明ZnO薄膜具有较好的结晶质量。     

生长温度对MOCVD外延ZnO纳米结构的影响

为了探究生长温度对外延ZnO纳米结构的影响,得到ZnO纳米结构可控生长的生长温度条件。利用金属有机化学气相沉积（MOCVD）方法,设计并获得了不同生长温度的ZnO外延样品,并对所有样品进行了表面形貌、光学特性、电学特性表征和结晶质量表征。实验结果表明:600℃生长的ZnO纳米柱横向尺寸最小,为65 nm左右,其光学特性也相对较好,晶体衍射峰的半峰宽最小,为0.165°,晶粒尺寸最大,为47.6 nm;电学性质相对最优的为640℃生长的ZnO样品,霍尔迁移率高达23.5 cm²/（V·s）。通过结果分析发现,生长温度能影响外延ZnO的生长模式,从而影响ZnO的形貌、光学、电学和晶体质量等特性。     

退火对ZnO薄膜光学特性的影响

用射频磁控溅射法在蓝宝石衬底上制备出ZnO薄膜,通过X射线衍射(XRD)、扫描电镜(SEM)和光致发光(PL)谱等研究了退火温度对ZnO薄膜结构和光学性质的影响。测量结果显示,所制备的ZnO薄膜为六角纤锌矿结构,具有沿c轴的择优取向;随着退火温度的升高,(002)XRD峰强度和平均晶粒尺寸增大,(002)XRD峰半高宽(FWHM)减小,光致发光紫外峰强度增强。结果证明,用射频磁控溅射法通过适当控制退火温度可得到高质量ZnO薄膜。     

溶胶-凝胶法制备Li-N双掺p型ZnO薄膜的结构、光学和电学性能

采用溶胶-凝胶法在n型Si(100)衬底上沉积Li-N双掺杂ZnO薄膜,经X射线衍射和扫描电镜图片分析,所制备薄膜具有多晶纤锌矿结构和高的c轴择优取向.室温下霍尔效应测试结果显示Li-N双掺杂ZnO薄膜具有p型导电特性.在Li掺杂量为15.0at%,Li/N（摩尔比）为1∶1,700℃退火等优化条件下得到的最佳电学性能结果是：电阻率为0.34 Ω·cm,霍尔迁移率为16.43 cm²/V·s,载流子浓度为2.79×10¹⁹ cm^{-3关键词： Li-N双掺 p型ZnO薄膜 溶胶-凝胶 性能}     

The influence of Au thickness on the structural,optical and electrical properties of ZnO/Au/ZnO multilayer films

Transparent and conductive ZnO/Au/ZnO (ZAZ) multilayer films were deposited on glass substrates by magnetron sputtering without intentional substrate heating. The thickness of Au interlayer was set at 1, 2 and 3 nm.The observed structural, optical and electrical properties were dependent on the thickness of the Au interlayer. For all of the ZAZ films, the diffraction peaks in the XRD pattern were identified as the (002) and (103) planes of a ZnO films and the (111) plane of an Au interlayer. The ZAZ films with a 2 nm thick Au interlayer showed a higher figure of merit than the other ZAZ films prepared in this study, and they also demonstrated the relatively high work function of 5.13 eV.From these results, we concluded that a ZAZ film with a 2 nm thick Au interlayer is an alternative candidate for use as a transparent electrode in OLEDs and various flat panel displays.     

Effects of Ag layer and ZnO top layer thicknesses on the physical properties of ZnO/Ag/Zno multilayer system

Two groups of transparent conductive ZnO/Ag/ZnO, ZAZ, multilayer coatings were successively deposited by direct current (DC) magnetron sputtering. Sputtering was carried out from zinc (Zn) and silver (Ag) metallic targets. The effects of Ag layer thickness and ZnO top layer thickness on the properties of the ZAZ multilayer system were examined using different analytical methods. The influences of the Ag layer thickness and ZnO top layer thickness on structural properties were studied using X-ray diffraction. The thicknesses of ZAZ multilayer system were determined using X-ray reflectometry. A sheet resistance of 2.3 Ω/sq at an Ag layer thickness of 17.7 nm was obtained. The sheet resistance changes slightly with ZnO top layer thickness. The optical properties of the films were analyzed. Both Ag layer thickness and ZnO top layer thickness affect transmittance. The optical constants of the ZAZ multilayer system were calculated from transmittance and reflectance measurements. The figure of merit was applied on the ZAZ coatings and the most suitable films for the application as transparent conductive electrodes were determined.     

ZnO/Ag/ZnO multilayer films for the application of a very low resistance transparent electrode

Transparent conductive ZnO/Ag/ZnO multilayer electrodes having much lower electrical resistance than the widely used transparent electrodes were prepared by simultaneous RF magnetron sputtering of ZnO and DC magnetron sputtering of Ag. An Ag film with different thickness was used as intermediate metallic layers. The optimum thickness of Ag thin films was determined to be 6 nm for high optical transmittance and good electrical conductivity. With about 20-25 nm thick ZnO films, the multilayer showed high optical transmittance in the visible range of the spectrum and had color neutrality. The electrical and optical properties of the multilayers were changed mainly by Ag film properties. A high quality transparent electrode, having sheet resistance as low as 3 ohm/sq and high transmittance of 90% at 580 nm, was obtained and could be reproduced by controlling the preparation parameter properly. The above property is suitable as transparent electrode for dye sensitized solar cells (DSSC).     

高浓度Er/Yb共掺ZnO薄膜的结构及室温光致发光特性

采用射频磁控溅射方法制备了Er/Yb共掺ZnO薄膜,研究了退火处理对高浓度Er/Yb共掺ZnO薄膜的结构演化和光致发光(PL)特性的影响。X射线衍射分析结果表明:Er/Yb掺杂导致ZnO薄膜的晶粒细化及择优取向性消失,ZnO晶粒随退火温度的增加而逐渐长大。900℃退火时,出现Er3 、Yb3 偏析,退火温度高于1000℃时,薄膜与基体间发生了界面反应,1200℃时,ZnO完全转变为Zn2SiO4相。光致发光测量结果表明:高于900℃退火处理后,Er/Yb共掺ZnO薄膜在1540 nm附近具有明显的光致发光,发光强度在退火温度为1050℃时达到最大值;光致发光光谱呈现典型的晶体基质中Er3 离子发光光谱所具有的明锐多峰结构特征。此外,探讨了薄膜结构演化及其对光致发光光谱的影响。     

背入射Au/ZnO/Al结构肖特基紫外探测器

设计制作了一种Au/ZnO/Al结构的紫外探测器,光的入射方式采用背入射式。ZnO薄膜是用磁控溅射在蓝宝石衬底上制备的。I-V测试表明:Au与ZnO形成了肖特基接触。得到探测器的光响应峰值在352nm,截止边为382nm,可见抑制比达一个量级。由于该探测器是一种垂直结构器件,对于进一步实现ZnO紫外探测器阵列及单光子探测有很好的研究价值。     

磁控溅射制备本征ZnO/Ag/ZnO透明导电薄膜的性质研究

室温下采用射频磁控溅射氧化锌（ZnO）粉末靶、银（Ag）靶,在玻璃衬底上制备ZnO/Ag/ZnO透明导电薄膜。首先,ZnO厚度为30 nm时,改变Ag厚度制备3层透明导电薄膜,研究Ag层厚度及膜层间配比对光电性能的影响;其次,按ZnO∶Ag厚度比为30∶11比例制备不同厚度的3层透明导电薄膜,研究多层厚度对薄膜光电性能的影响。结果表明：Ag厚度为8 nm及11 nm的ZnO/Ag/ZnO表面相对平整,结晶程度较好,在可见光范围内最高透过率达到90%及86%,并且方块电阻为6 Ω/□及3.20 Ω/□,具有优良的光电性;当按配比制备ZnO/Ag/ZnO 3层膜时,增加ZnO厚度对Ag层的增透作用反而减弱,同时增加Ag层厚度也会降低3层薄膜的整体光学性。     

The effects of post-thermal annealing on the optical parameters of indium-doped ZnO thin films

Indium-doped ZnO thin films are deposited on quartz glass slides by RF magnetron sputtering at ambient temper- ature. The as-deposited films are annealed at different temperatures from 400 C to 800 C in air for 1 h. Transmittance spectra are used to determine the optical parameters and the thicknesses of the films before and after annealing using a nonlinear programming method, and the effects of the annealing temperatures on the optical parameters and the thickness are investigated. The optical band gap is determined from the absorption coefficient. The calculated results show that the film thickness and optical parameters both increase first and then decrease with increasing annealing temperature from 400 C to 800 C. The band gap of the as-deposited ZnO:In thin film is 3.28 eV, and it decreases to 3.17 eV after annealing at 400 C. Then the band gap increases from 3.17 eV to 3.23 eV with increasing annealing temperature from 400 C to 800 C.     

NH3气氛处理制备p型ZnO薄膜及性能表征

采用NH₃气氛处理直流/射频共溅射方法制得的ZnO：Al薄膜,从而获得Al+N共掺p型ZnO薄膜.XRD,场发射扫描电子显微镜测试及Hall效应测试发现,处理温度对ZnO薄膜的结构和电学性能具有较大的影响,其中处理温度为700℃时,薄膜具有较好的c轴择优取向,并且薄膜表面平整,结构紧密,晶粒大小均匀,无明显空洞和裂缝,具有良好的表面质量,晶粒尺寸约为40—60nm,薄膜的导电类型由n型转变为p型. 关键词： p型ZnO Al+N共掺杂 直流/射频共溅射