ITO透明导电薄膜的反应离子刻蚀

研究了用 Ｃ Ｆ４ 或乙醇作为反应气体, Ａｒ 作为气体添加剂对 Ｉ Ｔ Ｏ 膜进行反应离子刻蚀,讨论了射频放电功率,反应室气压, Ａｒ 的流量对刻蚀速率的影响,得出了最佳工艺条件,并从理论上分析了刻蚀的机理。研究表明,用乙醇等有机气体对 Ｉ Ｔ Ｏ 膜进行反应离子刻蚀的效果更为理想。     

Transparent Zinc Oxide Gate Metal–Oxide–Semiconductor Field-Effect Transistor for High-Responsivity Photodetector

We report a new structure of high-responsivity photodetectors that utilizes the transparent and metallic zinc oxide (ZnO) gate in bulk silicon metal–oxide–semiconductor field-effect-transistor photodetectors. The device has a small optical window only in the channel region, and all other regions (depletion) are protected from external light. Whereas the amplification of photocurrent by external light was not significant at the floated or positively biased substrate, the photocurrent was enhanced at the grounded or negatively biased substrate due to the decrement of the recombination rate in the n-channel MOSFET. Responsivity was in excess of 1500 A/W under white-light illumination, which is higher than that of conventional photodetectors with the semitransparent polycrystalline-silicon gate.      

ITO透明导电薄膜的制备工艺研究

采用溶胶-凝胶法以InCl3·4H2O和SnCl4·5H2O为前驱物在玻璃基片上制备了ITO透明导电薄膜.详细研究了热处理初始温度、溶胶浓度、热处理温度、热处理时间、铟锡比例以及镀膜层数对薄膜光电特性的影响,得出了最佳工艺条件.结果表明,采用最佳工艺制备的ITO透明导电薄膜为体心立方的In2O3结构,Sn4 离子取代In2O3晶格中的In3 离子,样品不含低价氧化锡,薄膜方阻达到600 Ω/□,可见光透过率达到83%.     

Features of Indium Tin Oxide Film Deposition by Magnetron Sputtering

Journal of Communications Technology and Electronics - Abstract—Polycrystalline transparent conductive indium tin oxide layers are grown by direct current magnetron reactive sputtering of the...     

ITO纳米粉的低温制备

介绍了一种 ITO 纳米粉的低温、易于量产的制备方法。将铟锡氢氧化物置于充满氩气的高压釜,在 300℃、2 MPa 的条件下就可制得 5~20 nm 的 ITO 纳米粉。用 XRD、TEM 分析 ITO 纳米粉的形貌为纺锤状,结晶状况良好,更有利于制备高致密度靶材。与其它方法相比,本方法反应条件柔和,反应温度降低了约 200℃。     

氧化铟锡与掺Fe半绝缘GaN的接触特性

氧化铟锡(ITO)透明电极能够有效提高GaN光导半导体开关的光吸收效率和电场均匀性,但如何在透明电极ITO与半绝缘GaN之间实现良好的欧姆接触是一个难题.通过在ITO和半绝缘GaN之间插入与GaN功函数相近的Ti薄层,并利用快速热退火过程加速Ti与GaN之间的反应.研究发现Ti薄层的厚度和退火温度对欧姆接触有重要影响.在Ti薄层厚度为5 nm时,随着退火温度的升高,ITO/Ti/GaN之间的接触逐渐转变为欧姆接触,且接触电阻率随之减小;但当退火温度超过700℃时,欧姆接触变差,这与ITO中的In、Sn和O元素向界面扩散有关;适当提高Ti薄层的厚度可以有效改善ITO/Ti/GaN欧姆电极的热稳定性,但过厚的Ti薄层会对GaN基光电器件的透过率产生影响.     

玻璃基底上氧化铟锡薄膜的光致发光性能

用直流磁控溅射法在190℃玻璃基底上制备了氧化铟锡(ITO)薄膜,利用荧光分光光度计研究了ITO薄膜的光致发光性能。结果表明,室温下ITO薄膜在波长250 nm光源的激发下,分别在467 nm和751 nm处观察到了发光强度较强的蓝光宽带和强度较弱的红光带。上述发光峰的出现分别和ITO薄膜中的氧空位、铟空位等缺陷在禁带中形成的能级有关,其中氧空位形成的施主能级位于导带下1.2 eV处,而铟空位形成的受主能级位于价带下1.65 eV处。     

Solution‐Processed Metallic Nanowire Electrodes as Indium Tin Oxide Replacement for Thin‐Film Solar Cells

Solution processed silver nanowire (Ag NW) films are introduced as transparent electrodes for thin‐film solar cells. Ag NW electrodes were processed by doctor blade‐coating on glass substrates at moderate temperatures (less than 100 °C). The morphological, optical, and electrical characteristics of these electrodes were investigated as a function of processing parameters. For solar‐cell application, Ag NW electrodes with an average transparency of 90% between 450 and 800 nm and a sheet resistivity of ≈10 Ω per square were chosen. The performance of poly(3‐hexylthiophen‐2,5‐diyl):[6,6]‐phenyl‐C61‐butyric acid methyl ester (P3HT:PCBM) solar cells on Ag NW electrodes was found to match the performance of otherwise identical cells on indium tin oxide. Overall, P3HT:PCBM solar cells with an efficiency of 2.5% on transparent Ag NW electrodes have been realized.     

氧等离子体处理对ITO薄膜表面性能的影响

利用原子力显微镜研究氧等离子体处理对ITO薄膜的微观表面形貌及表面润湿性能的影响。实验结果表明:经过氧等离子体处理,ITO薄膜的平均粗糙度和峰-谷粗糙度减小,薄膜的平整度提高;而且表面吸附力增大近一倍,表面能增大,接触角减小,使ITO薄膜表面的润湿性能和吸附性能得到改善。     

干冰微粒喷射法清洗ITO玻璃的研究

对干冰微粒喷射法和低频超声波法清洗ITO玻璃的效果进行了比较研究.用接触角测量仪、SEM和XPS测量了清洗前后ITO玻璃表面的浸润性、污染颗粒数量和元素成分及含量等洁净度指标.研究表明,与超声波法清洗相比,干冰微粒喷射法清洗可以使ITO玻璃表面的接触角更小,有机碳含量减少40.5%,污染颗粒数量也显著减少,是一种清洗ITO玻璃的有效方法.     

High Mobility and Stability of Thin-Film Transistors Using Silicon-Doped Amorphous Indium Tin Oxide Semiconductors

We report the fabrication of high-performance thin-film transistors (TFTs) with an amorphous silicon indium tin oxide (a-SITO) channel, which was deposited by cosputtering a silicon dioxide and an indium tin oxide target. The effect of the silicon doping on the device performance and stability of the a-SITO TFTs was investigated. The field-effect mobility and stability under positive bias stress of the a-SITO TFTs with optimized Si content (0.22 at.% Si) dramatically improved to 28.7 cm²/Vs and 1.5 V shift of threshold voltage, respectively, compared with the values (0.72 cm²/Vs and 8.9 V shift) for a-SITO TFTs with 4.22 at.% Si. The role of silicon in a-SITO TFTs is discussed based on various physical and chemical analyses, including x-ray absorption spectroscopy, x-ray photoelectron spectroscopy, and spectroscopic ellipsometry measurements.     

Double-Recessed High-Frequency AlInGaN/InGaN/GaN Metal–Oxide Double Heterostructure Field-Effect Transistors

We demonstrate a low-threshold AlInGaN/InGaN/GaN metal-oxide semiconductor double heterostructure field-effect transistor (MOS-DHFET) for high-frequency operation. A combination of an InGaN channel (for carrier confinement), a DRE process, and a new digital-oxide-deposition technique helped us to achieve MOS-DHFET devices with extremely low subthreshold leakage currents. This reduction in output conductance (short channel effect) resulted in a high cutoff gain frequency f_T of about 65 GHz and a current gain frequency f _max of 94 GHz. The devices exhibited high drain-currents of 1.3 A/mm and delivered RF powers of 3.1 W/mm at 26 GHz with a 35 V drain bias.     

AlGaN/GaN Metal–Oxide–Semiconductor High-Electron Mobility Transistors Using Oxide Insulator Grown by Photoelectrochemical Oxidation Method

A photoelectrochemical oxidation method was used to directly grow oxide layer on AlGaN surface. The annealed oxide layer exhibited beta-Ga₂O₃ and alpha-Al₂O₃ crystalline phases. Using a photoassisted capacitance-voltage method, a low average interface-state density of 5.1 times 10¹¹ cm^-2. eV^-1 was estimated. The directly grown oxide layer was used as gate insulator for AlGaN/GaN MOS high-electron mobility transistors (MOS-HEMTs). The threshold voltage of MOS-HEMT devices is -5 V. The gate leakage currents are 50 and 2 pA at forward gate bias of VGS = 10 V and reverse gate bias of V_GS = -10 V, respectively. The maximum value of g_m is 50 mS/mm of VGs biased at -2.09 V.     

Solute Incorporation at Oxide–Oxide Interfaces Explains How Ternary Mixed‐Metal Oxide Nanocrystals Support Element‐Specific Anisotropic Growth

Fundamental understanding of anisotropic growth in oxide nanocrystals is crucial to establish new synthesis strategies and to tailor the nanoscale electronic, magnetic, optical, and electrocatalytic properties of these particles. While several growth investigations of metal alloy nanoparticles have been reported, mechanistic studies on the growth of ternary oxide materials are still missing. This work constitutes the first study on the evolution of anisotropic growth of manganese–cobalt oxide nanoparticles by monitoring the elemental distribution and morphology during the particle evolution via scanning transmission electron microscopy–X‐ray spectroscopy. A new growth mechanism based on a “solution‐solid‐solid” pathway for mixed manganese cobalt oxides is revealed. In this mechanism, the MnO seed formation occurs in the first step, followed by the surface Co enrichment, which catalyzes the growth along the <100> directions in all the subsequent growth stages, creating rod, cross‐, and T‐shaped mixed metal oxides, which preferentially expose {100} facets. It is shown that the interrelation of both Mn and Co ions initializes the anisotropic growth and presents the range of validity of the proposed mechanism as well as the shape‐determining effect based on the metal‐to‐metal ratio.     

Au-Doped Indium Tin Oxide Ohmic Contacts to <Emphasis Type="Italic">p</Emphasis>-Type GaN

Indium tin oxide (ITO) thin films doped with Au, Ni, or Pt (3.5 at.% to 10.5 at.%) were deposited on p-GaN epilayers (Mg ~4 × 10¹⁹ cm⁻³) using direct-current (DC) sputter codeposition. It was found that undoped ITO con- tacts to p-GaN exhibited leaky Schottky behavior, whereas the incorporation of a small amount of Au (3.5 at.% to 10.5 at.%) significantly improved their ohmic characteristics. Compared with standard Ni/ITO contacts, the Au-doped ITO contacts had a similar specific contact resistance in the low 10⁻² Ω cm⁻² range, but were more stable above 600°C and more transparent at blue wavelengths. These results provide support for the use of Au-doped ITO ohmic contact to p-type GaN in high-brightness blue light-emitting diodes.     

润湿角测试仪在ITO玻璃清洗工艺中的应用

在高质量产品的制造和高效率生产环境的构建中，电子测量技术起到了很大的作用，其重要性与日俱增，围绕ITO玻璃表面润湿性这一洁净度指标的测量为中心。重点介绍润湿角（又称接触角）测试仪的结构、测量ITO玻璃表面润湿性的工作原理和使用中应注意的事项。     

Metal–Oxide–High-$kappa$ Dielectric–Oxide–Semiconductor (MOHOS) Capacitors and Field-Effect Transistors for Memory Applications

Metal-oxide-high-kappa dielectric-oxide-silicon capacitors and transistors are fabricated using HfO₂ and Dy₂O₃ high-kappa dielectrics as the charge storage layer. The programming speed of Al/SiO₂/Dy₂O₃/ SiO₂/Si transistor is characterized by a DeltaV _th shift of 1.0 V with a programming voltage of 12 V applied for 10 ms. As for retention properties, the Al/SiO₂/Dy₂O₃/ SiO₂/Si transistors can keep a DeltaV _th window of 0.5 V for 2 times10⁸ s. The corresponding numbers for Al/ SiO₂/HfO₂/SiO₂/Si transistors are 100 ms and 2 times10⁴ s, respectively. The better performance of the Al/SiO₂/Dy₂O₃/ SiO₂/Si transistors is attributed to the larger conduction band offset at the Dy₂O₃/SiO₂ interface.     

生长速率对反应蒸发制备ITO薄膜光电性能的影响

用电阻加热反应蒸发的方法制备氧化铟锡(ITO)薄膜,测试了膜的电阻率、可见光透过率、载流子浓度和迁移率,讨论生长速率对薄膜光电性能的影响.并在衬底温度为160 ℃、反应压强为1.4×10-1 Pa的条件下,制得可见光范围平均透过率为93%、电阻率为4.7×10-4 Ω·cm的ITO透明导电薄膜.     

Preparation of Indium Tin Oxide films deposited by reactive evaporation at different substrate-temperature and the properties

The Indium Tin Oxide films have been prepared at different substrate-temperature on glass substrates by reactive evapora- tion of In-Sn alloy with an oxygen pressure of 1.3 ×10-1 Pa and a deposition rate of 10-2 nm/s. The best ITO films obtained have an electrical resistivity of 4.35 × 10-4 ??cm , a carrier concentration of 4.02 × 1020 cm-3 , and a Hall mobility of 67.5 cm2v-1s-1. The influence of the substrate-temperature on the structural , optical and electrical properties of the obtained films has been investigated.     

Nanoscale Investigation of Grain Growth in RF-Sputtered Indium Tin Oxide Thin Films by Scanning Probe Microscopy

This work studied the electronic characteristics of the grains and grain boundaries of indium tin oxide (ITO) thin films using electrostatic and Kelvin probe force microscopy. Two types of ITO films were compared, deposited using radiofrequency magnetron sputtering in pure argon or 99% argon + 1% oxygen, respectively. The average grain size and surface roughness increased with substrate temperature for the films deposited in pure argon. With the addition of 1% oxygen, the increase in the grain size was inhibited above 150°C, which was suggested to be due to passivation of the grains by the excess oxygen. Electrostatic force microscopy and Kelvin probe force microscopy (KPFM) images confirmed that the grain growth was defect mediated and occurred at defective interfaces at high temperatures. Films deposited at room temperature with 1% oxygen showed crystalline nature, while films deposited with pure argon at room temperature were amorphous as observed from KPFM images. The potential drop across the grain and grain boundary was determined by taking surface potential line profiles to evaluate the electronic properties.