衬底温度对磁控溅射法制备ZnO薄膜结构及光学特性的影响

采用射频反应磁控溅射法在玻璃衬底上制备了具有c轴高择优取向的ZnO薄膜,利用X射线衍射仪、扫描探针显微镜及紫外分光光度计研究了生长温度对ZnO薄膜的结构及光学吸收和透射特性的影响.结果表明,合适的衬底温度有利于提高ZnO薄膜的结晶质量;薄膜在紫外区显示出较强的光吸收,在可见光区的平均透过率达到90%以上,且随着衬底温度的升高,薄膜的光学带隙减小、吸收边红移.采用量子限域模型对薄膜的光学带隙作了相应的理论计算,计算结果与实验值符合得较好.     

衬底温度对PLD法制备ZnO薄膜结构及发光特性的影响

在60Pa的高氧压气氛中,用脉冲激光沉积法以Si(111)为衬底在不同温度下制备了ZnO薄膜.RHEED和XRD结果表明,所有样品都是c轴高度择优取向的多晶ZnO薄膜.随衬底温度的升高,ZnO薄膜(002)衍射峰的半高宽不断减小,从0.227～0.185°.对(002)衍射峰的2θ值分析表明,650℃下生长的ZnO薄膜几乎处于无应力的状态,而在较低或较高温度下生长的薄膜中都存在着一定程度的c轴压应力.室温PL谱测试说明在650℃生长的ZnO薄膜具有最强的紫外发射峰和最窄的UV峰半高宽(83meV).在700℃得到的样品PL谱中,检测到一个位于3.25eV处的低能发射峰.经分析,该峰可能是来自于施主-受主对(DAP)的跃迁.     

衬底温度对磁控溅射制备外延ZnO薄膜结构特性的影响

在不同的衬底温度下,采用磁控溅射方法在蓝宝石(0001)衬底上制备了外延生长的ZnO薄膜.采用原子力显微镜(AFM)、X射线衍射仪(XRD)、可见-紫外分光光度计系统研究了衬底温度对ZnO薄膜微观结构和光学特性的影响.AFM结果表明在不同村底温度制备的ZnO薄膜具有较为均匀的ZnO晶粒,且晶粒的尺寸随衬底温度的增加逐渐增大.XRD结果显示不同温度生长的ZnO薄膜均为外延生长,400℃生长的薄膜具有最好的结晶质量;光学透射谱显示在370nm附近均出现一个较陡的吸收边,表明制备的ZnO薄膜具有较高的质量,其光学能带隙随着衬底温度的增加而减小.     

衬底温度对直流磁控溅射法沉积ZnO∶Ti薄膜性能的影响

利用直流磁控溅射工艺,在石英玻璃衬底上沉积出了具有高度C轴择优取向的掺Ti氧化锌(ZnO∶Ti,TZO)透明导电薄膜。研究了衬底温度对TZO薄膜应力、结构和光电性能的影响。结果表明,衬底温度对TZO薄膜的结构、应力和电阻率有重要影响。TZO薄膜为六角纤锌矿结构的多晶薄膜。在衬底温度为100℃时,实验获得的TZO薄膜电阻率具有最小值2.95×10-4Ω.cm,400℃时薄膜出现孪晶,随着温度的升高,薄膜应力具有减小的趋势。实验制备的TZO薄膜附着性能良好,可见光区平均透过率都超过91%。     

直流磁控溅射ZnO薄膜的结构和室温PL谱研究

ZnO是一种新型的宽带化合化半导体材料 ,对短波长的光电子器件如UV探测器 ,LED和LD有着巨大的潜在应用。本实验研究采用直流反应磁控溅射法在硅衬底上沉积C轴择优取向的ZnO晶体薄膜 ,薄膜呈柱状结构 ,晶粒大小约为 10 0nm ,晶粒内为结晶性能完整的单晶 ,但晶粒在C轴方向存在较大的张应力。ZnO薄膜在He Cd激光器激发下有较强的紫外荧光发射 ,应力引起ZnO禁带宽度向长波方向移动 ,提高衬底温度有利于降低应力和抑制深能级的绿光发射     

氧氩比对磁控溅射ZnO薄膜结构及光致发光性能的影响

采用射频反应磁控溅射法以不同的氧氩比在玻璃衬底上制备了ZnO薄膜,并对薄膜进行了退火处理;利用X射线衍射仪（XRD）和原子力显微镜（AFM）分别对薄膜的物相组成和表面形貌进行了分析,利用荧光分光光度计对ZnO薄膜的室温光致发光（PL）谱进行了测试。结果表明：当氧氩气体积比为7∶5时,所制备的ZnO薄膜晶粒细小均匀,薄膜结晶质量最好;ZnO薄膜具有紫光、蓝光和绿光三个发光峰,随着氧氩比的增加,蓝光的发射强度增强,而紫光和绿光的发射强度先增强后减弱,当氧氩气体积比为7∶5时紫光和绿光的发射强度最强。     

直流磁控溅射ZnO薄膜的结构和室温PL谱研究

ZnO是一种新型的宽带化合化半导体材料，对短波长的光电 子器件如UV探测器，LED和LD有着巨大的潜在应用。本实验研究采用直流反应磁控溅射法在硅衬底上沉积C轴择优取向的ZnO晶体薄膜，薄膜呈柱状结构，晶粒大小约为100nm，晶粒内为结晶性能完整的单晶，但晶粒在C轴方向存在较大的张应力。ZnO薄膜在He-Cd激光器激发下有较强的紫外荧光发射，应力引起ZnO禁带宽度向长波方向移动，提高衬底温度有利于降低应力和抑制深能级的绿光发射。     

不同衬底上ZnO薄膜的射频磁控溅射制备及结构

利用射频磁控溅射镀膜的方法,在c面蓝宝石、石英玻璃和载破片衬底上成功制备了ZnO薄膜。用x射线衍射和扫描电子显微镜进行了结构分析并观察了样品的表面形貌。结果表明：制备的ZnO薄膜具有良好的C轴择优取向结晶度,并在石英玻璃和载玻片衬底上的ZnO薄膜表面发现了[101]取向的“米粒状”晶粒。     

衬底温度对磁控溅射氮化铝薄膜组成的影响

采用高纯铝靶和氮/氩混合气氛,在玻璃衬底上用直流反应磁控溅射法制备了AlN薄膜,用X射线光电子能谱(XPS)分析了不同衬底温度下样品的组成.结果表明,AlN薄膜主要含有AlN,存在少量Al2O3及一些其它杂质;随着基片温度的升高,AlN薄膜的纯度提高.     

直流磁控溅射制备氮化铜薄膜的热稳定性研究

用直流磁控溅射方法,在氮气分压为0．5Pa、不同的基底温度下,于玻璃基底上制备了Cu3N薄膜。当基底温度为100℃及以下时,温度越高薄膜的结晶程度越好。当基底温度在100℃以上时,随着基底温度的升高,薄膜的结晶程度逐渐减弱,200℃时结晶已很弱,300℃时已完全不能形成Cu3N晶体。薄膜的电阻率随基底温度的变化不大,薄膜的沉积速率随基底温度的升高在18～30nm／min之间近似地线性增大,薄膜的显微硬度随基底温度的升高而略有降低。对基底温度为室温和100℃下制备的氮化铜薄膜进行不同温度下的真空退火,研究了它们的热稳定性。XRD测试表明,薄膜在200℃时开始出现分解,350℃时完全分解。比较在基底温度为室温和100℃下制备的样品,发现室温下制备的氮化铜薄膜比100℃下制备的氮化铜薄膜稳定。     

Influence of substrate temperature on N-doped ZnO films deposited by RF magnetron sputtering

Nitrogen-doped ZnO films were deposited by RF magnetron sputtering in 75% of N₂ / (Ar + N₂) gas atmosphere. The influence of substrate temperature ranging from room temperature (RT) to 300 °C was analyzed by X-ray diffractometry (XRD), spectrophotometry, X-ray photoelectron spectroscopy (XPS), secondary-ion mass spectrometry (SIMS) and Hall measurements setup. The XRD studies confirmed the hexagonal ZnO structure and showed that the crystallinity of these films increased with increasing substrate temperature (T_s). The optical studies indicate the average visible transmittance in the wavelength ranging 500-800 nm increases with increasing T_s. A minimum transmittance (9.84%) obtained for the films deposited at RT increased with increasing T_s to a maximum of 88.59% at 300 °C (500-800 nm). Furthermore, it was understood that the band gap widens with increasing T_s from 1.99 eV (RT) to 3.30 eV (250 °C). Compositional analyses (XPS and SIMS) confirmed the nitrogen (N) incorporation into the ZnO films and its decreasing concentration with increasing T_s. The negative sign of Hall coefficients confirmed the n-type conducting.     

Mn-doped ZnO transparent conducting films deposited by DC magnetron sputtering

Mn-doped zinc oxide (ZnO:Mn) thin films with low resistivity and relatively high transparency were firstly prepared on glass substrate by direct current (DC) magnetron sputtering at room temperature. Influence of film thickness on the properties of ZnO:Mn films was investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that all the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. As the thickness increases from 144 to 479 nm, the crystallite size increases while the electrical resistivity decreases. However, as the thickness increases from 479 to 783 nm, the crystallite size decreases and the electrical resistivity increases. When film thickness is 479 nm, the deposited films have the lowest resistivity of 2.1 × 10^− 4 Ω cm and a relatively high transmittance of above 84% in the visible range.     

Substrate temperature dependence of the properties of Ga-doped ZnO films deposited by DC reactive magnetron sputtering

Ga-doped zinc oxide (ZnO:Ga) transparent conductive films were deposited on glass substrates by DC reactive magnetron sputtering. The influence of substrate temperature on the structural, electrical, and optical properties of ZnO:Ga films was investigated. The X-ray diffraction (XRD) studies show that higher temperature helps to promote Ga substitution more easily. The film deposited at 350 °C has the optimal crystal quality. The morphology of the films is strongly related to the substrate temperature. The film deposited is dense and flat with a columnar structure in the cross-section morphology. The transmittance of the ZnO:Ga thin films is over 90%. The lowest resistivity of the ZnO:Ga film is 4.48×10⁻⁴ Ω cm, for a film which was deposited at the substrate temperature of 300 °C.     

Properties of Ce-doped ITO films deposited on polymer substrate by DC magnetron sputtering

Ce-doped indium tin oxide (ITO:Ce) films were deposited on flexible polyimide substrates by DC magnetron sputtering using ITO targets containing various CeO₂ contents (CeO₂ : 0, 0.5, 3.0, 4.0, 6.0 wt.%) at room temperature and post-annealed at 200 °C. The crystallinity of the ITO films decreased with increasing Ce content, and it led to a decrease in surface roughness. In addition, a relatively small change in resistance in dynamic stress mode was obtained for ITO:Ce films even after the annealing at high temperature (200 °C). The minimum resistivity of the amorphous ITO:Ce films was 3.96 × 10^− 4 Ωcm, which was deposited using a 3.0 wt.% CeO₂ doped ITO target. The amorphous ITO:Ce films not only have comparable electrical properties to the polycrystalline films but also have a crystallization temperature > 200 °C. In addition, the amorphous ITO:Ce film showed stable mechanical properties in the bended state.     

Effect of substrate temperature on the structure and optical properties of ZnO thin films deposited by reactive rf magnetron sputtering

Zinc Oxide films were deposited on quartz substrates by reactive rf magnetron sputtering of zinc target. The effect of substrate temperature on the crystallinity and band edge luminescence has been studied. The films deposited at 300 °C exhibited the strongest c-axis orientation. AFM and Raman studies indicated that the films deposited at 600 °C possess better overall crystallinity with reduction of optically active defects, leading to strong and narrow PL emission.     

Lithium cobalt oxide thin films deposited at low temperature by ionized magnetron sputtering

Thin films of lithium cobalt oxides have been deposited by ionized magnetron sputter deposition with and without substrate heating. The technique uses a built-in radio frequency coil to generate an inductively coupled plasma (ICP) confined close to the substrate. The ICP plasma results in ion bombardment on the film surface, which serves as an extra energy input during film growth. Therefore, the film properties can be modified at a relatively lower temperature. The plasma irradiation induces variations of crystallography and morphology, as characterized by X-ray diffraction and scanning electron microscopy. The deposited films were tested as cathodes for lithium batteries, and the discharge curves were measured to compare the electrochemical properties of the deposited films. Applying suitable plasma irradiation, well crystallized LiCoO₂ phase was obtained at 350 °C (substrate temperature), which was much lower than the temperature (700 °C-750 °C) for conventional post anneal process. The LiCoO₂ films, fabricated under in-situ plasma irradiation and a relatively lower substrate temperature (350 °C), showed a discharge potential plateau at 4.3 V-3.8 V with a capacity of ∼ 110 mAh/g as discharged to 1.5 V.     

衬底温度对射频磁控溅射制备HfO2薄膜结构的影响

采用射频磁控溅射法在氧氩比为0.2的混合气氛中,分别在室温、100℃、200℃、250℃、300℃、350℃和400℃温度下,在P-Si(100)衬底上制备了HfO2薄膜,并用SEM、XRD和AFM研究了衬底温度与薄膜沉积速率对微结构的影响.结果表明:随着衬底温度的增加,薄膜沉积速率呈减小趋势.室温沉积的HfO2薄膜为非晶态,当衬底温度高于100℃,薄膜出现单斜晶相,随着衬底温度继续增加,(111)择优取向更加明显,晶粒尺寸增大,薄膜表面粗糙度减小.     

溅射功率对磁控溅射ZnO∶Al(ZAO)薄膜性能的影响

采用射频磁控溅射工艺,以高密度氧化锌铝陶瓷靶为靶材,衬底温度控制在室温,在玻璃基底上制备了透明导电Zn O∶Al(ZAO)薄膜。利用X射线衍射仪(XRD)、原子力显微镜(AFM)、紫外-可见光谱仪和范德堡法,系统研究了不同溅射功率对薄膜的结构、形貌及光电特性的影响。结果表明,不同溅射功率对薄膜的光透射率影响不大,而对薄膜结晶和电学性能影响较大。XRD表明薄膜为良好的c轴择优取向;可见光区(400~600 nm)平均透过率达到85%以上;在120W下沉积的薄膜电学性能达到了最佳。     

Effect of target properties on transparent conducting impurity-doped ZnO thin films deposited by DC magnetron sputtering

For the purpose of using transparent conducting impurity-doped ZnO thin films in liquid crystal display (LCD) applications, the relationship between the properties of dc magnetron sputtering (dc-MS) deposited thin films and the properties of the oxide targets used to produce them is investigated. Both Al-doped and Ga-doped ZnO (AZO and GZO) thin films were deposited on glass substrates using a dc-MS apparatus with various high-density sintered AZO or GZO disk targets (diameter of about 150 mm); the target and substrate were both fixed during the depositions. Using targets with a lower resistivity results in attaining more highly stable dc-MS depositions with higher deposition rates and lower arcing. In addition, dc-MS depositions using targets with a lower resistivity produced improvements in resistivity distribution on the substrate surface. It was found that the oxygen content in deposited thin films decreased as the oxygen content of the target used in the deposition was decreased. As a result, the dc-MS deposition of transparent conducting impurity-doped ZnO thin films suitable for LCD applications requires the preparation of significantly reduced AZO and GZO targets with low oxygen content.