室温直流反应磁控溅射制备透明导电In_2O_3∶Mo薄膜

在室温条件下采用直流反应磁控溅射法制备了新型透明导电In2O3∶Mo薄膜。研究了溅射压强中氧气百分含量[P(O2)]为8.0%~18.0%时对薄膜光电特性以及表面形貌结构的影响。结果表明,薄膜的光电性能对溅射压强中P(O2)非常敏感。分析显示P(O2)决定了薄膜中的氧空位含量和载流子浓度,从而影响了薄膜的光电特性。原子力显微镜观察表明,适量的P(O2)条件下可以获得平均粗糙度为0.3 nm、颗粒均匀、表面平整的薄膜。室温制备的IMO薄膜在可见光区域的平均透射率(含玻璃基底)高达82.1%,电阻率低至5.9×10-4Ω.cm。     

ITO薄膜的制备以及性能的研究

在室温条件下通过直流磁控溅射法在普通玻璃基体上制备了光电性能优良的ITO薄膜。靶材为ITO陶瓷靶,其中In2O3与SnO2的质量比为9∶1。运用UV-2550紫外可见光光度计测量样品的透光率,采用SZT-2四探针测试仪测量样品表面的电阻率,用扫描电镜(SEM)对样品进行表征。研究了溅射压强、溅射功率等参数对薄膜光电性能的影响。研究表明,ITO薄膜的电阻率随着溅射功率的增大而减小,在溅射功率为110W时ITO薄膜的透光率有相对好的数值。溅射压强为1.0Pa时既能保持ITO薄膜低的电阻率又能保证高的透光率。     

氩气压强对直流磁控溅射法制备ZnO:Nb透明导电薄膜性质的影响

室温下,利用直流磁控溅射法在玻璃衬底上制备了铌掺杂氧化锌(NZO)薄膜,研究了溅射压强(2～12 Pa)对薄膜结构、残余应力、表面形貌及其光电性能的影响.X射线衍射测量结果表明,所有样品都具有c轴择优取向的六角纤锌矿多晶结构,薄膜应力随压强的增大而减小.扫描电镜表明,随着溅射压强的增大,薄膜表面逐步趋向平整光滑、均匀致密.当溅射压强为10 Pa时,制备的ZnO∶Nb薄膜的最低电阻率可达3.52× 10-4 Ω·cm,残余应力为-0.37 GPa.压强由2Pa增大到12 Pa时,光学带隙由3.29eV增大到3.43 eV.紫外-可见透射光谱表明,所有薄膜在可见光范围内平均透过率均超过87％.     

In_2O_3：W薄膜的制备及光电性能研究

采用直流磁控溅射法制备了掺钨氧化铟（In2O3：W,IWO）薄膜,研究了制备工艺对薄膜表面形貌和光电性能的影响。结果表明薄膜的表面形貌与其光电性能有着紧密联系。氧分压显著影响薄膜的表面形貌进而对薄膜的光电性能产生影响,同时溅射时间的变化也显著影响薄膜的光电性能：随着氧分压以及溅射时间的升高,薄膜的电阻率均呈现先减小后增大的变化规律,在氧分压为2.4×10-1Pa条件下,制备样品的表面晶粒排布最细密,其电阻率达到6.3×10-4Ω.cm,载流子浓度为2.9×1020cm-3,载流子迁移率为34cm2/（V.s）,可见光平均透射率约为85%,近红外光平均透射率〉80%。     

室温直流磁控溅射制备ITO膜及光电性能研究

室温条件下,在玻璃衬底上,采用直流磁控溅射法制备了ITO膜.研究了溅射压强,氧流量和溅射功率等工艺参数对薄膜光电性能的影响.结果表明当Ar流量为44.2 sccm和溅射时间20 min等参数不变时,溅射气压0.7 Pa,氧流量0.62 sccm和溅射功率130 W为最佳工艺条件.并得到了电阻率5.02×10-4 Ω·cm,在可见光区平均透过率80%以上ITO薄膜.     

Ar气氛下直流磁控溅射ITO薄膜的结构和性能

采用直流磁控溅射法在低温、100%Ar的无氧气氛中制备了光电性能优良的铟锡氧化物(ITO,In2O3:SnO2=90:10,质量百分比)薄膜,详细探讨了溅射时改变氩气压强对ITO薄膜结构以及光电性能的影响.结果表明:溅射时氩气压强越小,ITO薄膜的体心立方晶型越完整,导电性越好,但对可见光透过性的影响不大.当氩气压强为0.3Pa时,溅射薄膜性能最佳,其光透过率可达92.9%,电导率为8.9×10-4Ω·cm.     

室温制备P型透明导电CuO:Ni薄膜的研究

在自主研发的一系列P型导电Cu1-xNixO靶材基础上,选择具有最佳电导率的Cu0.95Ni0.05O靶材,采用脉冲等离子体沉积技术在室温条件下普通玻璃衬底上制备了Cu0.95Ni0.05O透明导电薄膜.Seebeck系数测试表明所有薄膜均为P型导电.通过x射线衍射和扫描电子显微镜分别研究了薄膜的品格结构和表面形貌,证实了所制备薄膜均为非晶结构.研究了氧气压强、脉冲电压和脉冲电流等成膜条件对薄膜电学性能和光学性能的影响.在氧气压强为3.0 Pa,脉冲电压为-18 kV,脉冲电流为4.5 mA条件下,获得了电导率最大值7.1 S·cm-1,可见光区域的平均透射率为65%,光学禁带宽度为4.3 eV的光电性能相对优良的P型透明导电薄膜.     

磁控溅射制备镁镓共掺氧化锌透明半导体薄膜及其性能研究

以MgO∶Ga_2O_3∶ZnO(2%∶2%∶96%,质量分数)陶瓷靶作为溅射源,采用磁控溅射技术在石英玻璃衬底上制备了镁镓共掺氧化锌(MGZO)透明半导体薄膜。采用XRD、SEM、霍尔效应仪和分光光度计对MGZO薄膜进行测试表征,研究了溅射压强对MGZO薄膜晶体结构、电学性质和光学性能的影响。结果表明:所有MGZO薄膜均为六角纤锌矿结构并具有(002)择优取向生长特性,溅射压强对薄膜晶体结构和光电性能有明显影响,但几乎不影响其直接光学能隙(3.41~3.44eV)。当溅射压强为3.5Pa时,MGZO薄膜的结晶质量最好、张应力最小(8.29×10-2 GPa)、电阻率最低(1.62×10-3Ω·cm)、可见光区平均透过率最高(87.8%)、品质因数最大(4.76×103Ω~(-1)·cm~(-1)),具有最好的光电综合性能。     

室温下高速沉积AZO薄膜的研究

在室温下,采用射频磁控溅射技术以较大的功率密度(7W/cm2)沉积了一系列掺铝氧化锌(AZO)透明导电薄膜,探索了溅射压强对沉积速率及薄膜性能的影响。结果表明,当工作压强为2.0Pa时,高速(67nm/min)沉积得到的薄膜的电阻率为2.63×10-3Ω.cm,可见光平均透过率为83%,并且在薄膜表面有一定的织构。     

氧化锌掺钇透明导电薄膜的制备及光电特性研究

采用射频磁控溅射法,室温下在玻璃衬底上制备出了具有良好附着性、低电阻率和高透过率的新型透明导电薄膜YZO(ZnO掺杂Y2O3简称YZO)。在薄膜厚度为600nm的情况下,研究了薄膜电学特性随溅射功率和溅射气压的变化情况。X射线衍射谱表明YZO薄膜是多晶膜,具有ZnO的六角纤锌矿结构,最佳取向为(002)方向。最佳溅射条件下制备的薄膜电阻率为8.71×10-4Ω.cm,在可见光范围内平均透过率达到92.3%,禁带宽度为3.57eV。     

Electronic structure and formation mechanism of complex Ti-Nb oxide

Two-layer thin film specimens of Nb₂O₅ and TiO₂ were deposited on optical-grade quartz and n-type single crystalline silicon substrates with (100) crystallographic orientation by a magnetron deposition source under high vacuum. All samples were subjected to 1-5 h of resistive heating at ultra high vacuum, and in situ X-ray diffraction measurements (XRD) were made in the temperature range of 300-1373 K. Analysis of the XRD data confirmed the growth of TiNbO₄ during cooling of the two-layered specimens which had been previously heated to 1373 K. Optical measurements revealed a band gap value of 3.78 eV for the direct transition and 3.29 eV for the indirect one. The samples had a transmittance of 85% in the visible range. Electrophysical measurements in high vacuum established the electroresistivity vs. temperature dependence in the range of 300-773 K, from 7.3 ? 10^− 1 to 3.9 ? 10^− 2 Ω cm, respectively. X-ray photoelectron spectroscopy measurements were used to examine the chemical shift for Nb 3d, with a value of − 1.1 eV in comparison with Nb⁵⁺ and matched to Nb⁴⁺[1], while the Ti lines correspond to Ti⁴⁺[2].     

Optical properties of thin films of mixed Ni-W oxide made by reactive DC magnetron sputtering

Thin films of Ni_xW_1 − x oxides with x = 0.05, 0.19, 0.43 and 0.90 were studied. Films with thicknesses in the range 125-250 nm were deposited on silicon wafers at room temperature by reactive DC magnetron co-sputtering from targets of Ni and W. The films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and spectroscopic ellipsometry (SE). XRD spectra and SEM micrographs showed that all films were amorphous and possessed a columnar structure. The ellipsometric angles Ψ and Δ of as-deposited films were measured by a rotating analyzer ellipsometer in the UV-visible-near infrared range (0.63-6.18 eV) and by an infrared Fourier transform rotating compensator ellipsometer in the 500-5200 cm⁻¹ wavenumber range. SE measurements were performed at angles of incidence of from 50 ° to 70 °. Parametric models were used to extract thicknesses of the thin films and overlayers of Ni_xW_1 − x oxide at different compositions, band gaps and optical constants. Features in the optical spectra of the Ni_xW_1 − x oxides were compared with previous data on tungsten oxide, nickel oxide and nickel tungstate.     

High k dielectrics for low temperature electronics

In this work the electrical and structural properties of two high k materials as hafnium oxide (HfO₂) and tantalum oxide (Ta₂O₅) produced at room temperature are exploited. Aiming low temperature processing two techniques were employed: r.f. sputtering and electron beam evaporation.The sputtered HfO₂ films present a nanocrystalline structure when deposited at room temperature. The same does not happen for the evaporated films, which are essentially amorphous. The density and the electrical performance of both sputtered and evaporated films are improved after annealing them at 200 °C. On the other hand, the Ta₂O₅ samples deposited at room temperature are always amorphous, independently of the technique used. The density and electrical performance are not so sensitive to the annealing process. The set of data obtained show that these dielectrics processed at temperatures below 200 °C present promising properties aiming to produce devices at low temperature with improved interface properties and reduced leakage currents.     

Facile Synthesis of SnO2 Nanotube Arrays by Using ZnO Nanorod Arrays as Sacrificial Templates

SnO2 nanotube arrays have been synthesized by means of a simple and low-cost method. The ZnO nanorod arrays prepared by aqueous chemical growth method were used as templates. By liquid phase deposition, SnO2 nanotubes were obtained with proper deposition time. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction were used to characterize the morphologies and structures of the products, and the formation mechanism was discussed according to the experimental results.     

All-solid-state reflectance-type electrochromic devices using iridium tin oxide film as counter electrode

We prepared an all-solid-state reflectance-type electrochromic device (ECD), consisting of the following five layers: Al/WO₃/Ta₂O₅/Ir_xSn_1 − xO₂/ITO. Using RF ion plating, we prepared a film containing dispersed iridium oxide in a tin oxide matrix; this film acts as the counter electrode in the all-solid-state ECD. Protons were used as coloration ions in the ECD. The size of the ECD was 150 cm², and the reflectance changed between more than 60% from 15%. The coloration and bleaching response times were less than a few seconds. We analyze the optical characteristics of the ECD, and report the results of a consecutive drive test and a high-temperature heat resistance test.     

Comparative study on early stages of film growth for transparent conductive oxide films deposited by dc magnetron sputtering

Early stages of film growth were investigated on three different kinds of representative transparent conductive oxide films including tin doped indium oxide (ITO), indium zinc oxide (IZO) and gallium doped zinc oxide (GZO) films deposited on unheated alkali free glass substrates by dc magnetron sputtering. The variations in sheet resistance, film coverage and average surface roughness showed clearly that ITO and GZO films possessed Volmer-Weber growth mode. In contrast, the evolution of islands is not clearly observed for IZO film. The nucleation density of IZO film is considered to be much higher than that of ITO and GZO films.     

纳米氧化物的合成新方法

以草酸和醋酸盐为原料,用低热固相化学反应合成出前驱配合物ＮｉＣ２Ｏ４·２Ｈ２Ｏ,ＣｕＣ２Ｏ４ 和ＺｎＣ２Ｏ４·２Ｈ２Ｏ,再分别在３５０℃,３００ ℃和４６０℃热分解２ｈ,得到纳米ＮｉＯ,ＣｕＯ和ＺｎＯ。用Ｘ－ 射线粉末衍射、透射电镜对产物的组成、大小、形貌进行表征。结果表明,纳米ＮｉＯ为球形立方晶系结构,平均粒径约为４０ｎｍ 左右;纳米ＣｕＯ为球形单斜晶系结构,平均粒径约为３０ｎｍ 左右;ＺｎＯ为粒度分布均匀的球形六角晶系结构,平均粒径约为２０ｎｍ 。     

Highly conductive, undoped ZnO thin films deposited by electron-cyclotron-resonance plasma sputtering on silica glass substrate

The electrical and optical properties of undoped ZnO films deposited by electron cyclotron resonance (ECR) plasma sputtering at room temperature were characterized. The lowest resistivity we achieved was 2.6 × 10^− 3 Ωcm with optical transmittance at visible wavelengths higher than 85%. The X-ray diffraction (002) peak was weak and the rocking curve was asymmetrical, indicating that oxygen vacancies prevented large crystalline domains from forming. At low argon-sputtering-gas pressure, carrier concentration and Hall mobility increased with increasing argon pressure. When the optimum pressure (40 mPa) was exceeded, however, Hall mobility and optical transmittance were severely reduced, which indicated that excess Zn atoms were populated at the interstitials of the network. Admitting only 0.67 mPa of O₂ gas during deposition deteriorated resistivity over 1 MΩcm due to high excitation efficiency in the ECR plasma. Deposition under a higher magnetic field produced lower resistivities.     

Microstructure and Mechanical Properties of ZrO2(2Y)-Toughened Al2O3 Ceramics Fabricated by Spark Plasma Sintering

Spark plasma sintering (SPS) has been performed for 5 min at 1500°C and 30 MPa using submicrometer-sized Al₂O₃/ZrO₂(2Y) composite powders in the Al₂O₃-rich region. Dense ZrO₂-toughened Al₂O₃ (ZTA) ceramics show excellent mechanical strength; the strength of 1620 MPa is achieved in the ZTA with 50 mol% ZrO₂. The grain size of Al₂O₃ in ZTA decreases from 1.5 to 0.6 m with increased ZrO₂ content. Almost all the ZrO₂ grains (0.3 m) are located in the boundaries of the Al₂O₃ grains. Mechanical properties are discussed, with an emphasis on the relation between t-/m-ZrO₂ ratios and microstructures of ZTA.