A Comparative Study on the Microstructure and Properties of ITO Targets and Thin Films Prepared from Two Different Powders

With the rapid development of indium tin oxide(ITO) in the electronic display industry, choosing which raw powders to prepare high-quality ITO targets has always been a controversial topic. In the work, in order to clearly understand the effect of the raw powders on the microstructure and properties of ITO targets and thin films, tin-doped indium oxide(dITO) and In_2O_3-SnO_2 mixed(mITO) powders were chosen to prepare ITO targets for depositing the films and a comparative study on their microstructure and properties was conducted. It is found that,(1) dITO targets possess a higher solid solubility of tin in indium oxide and more uniform elemental distribution, while there are a higher density, a finer grain size and a higher mass ratio of In_2 O_3 to SnO_2 for the mITO targets;(2) dITO films with more coarser columnar grains and a rougher surface prefer to grow along the [100] direction in an Ar atmosphere;(3) the conductive property of ITO films only depends on the doping amount of tin and is independent of the raw powders and the preparation process of the target source;(4) dITO films possess the superior optical property and narrower optical band gap;(5) the etching property of mITO films is superior to that of dITO films due to the lower solid solubility of tin in indium oxide.     

纳米级ITO粉体对烧结法制备靶材的影响

采用化学共沉淀法制备ITO前驱物,分别于600及1000℃下热处理前驱物,得到两种ITO粉体.粉体模压成型得到素坯,在400～1550℃内采用烧结法、氧气氛下烧结素坯制备出ITO靶材.对粉体及靶材进行表征和分析,研究了烧结过程中晶粒生长情况、靶材微结构与温度之间关系及靶材的失氧现象.得出600℃粉体为单相ITO固溶体、粒径为15 nm,1000℃粉体有少量SnO2析出、粒径为28 nm且其分散性和晶化程度优于600℃的粉体.两种粉体烧结制备靶材过程符合Coble固相烧结理论,1550℃时晶体出现类似二维成核生长方式的生长台阶.靶材密度随温度升高而增加,1550℃时随保温时间延长而增加.靶材致密化过程由团聚程度及团聚体大小决定,1000℃粉体制备的靶材密度高于600℃粉体所制靶材.两类靶材含氧量均低于理论值,1000℃粉体所制靶材含氧量高于600℃的含氧量.     

纳米ITO粉末及高密度ITO靶制备工艺的研究现状

对铟锡氧化物ITO(Indium Tin Oxide)纳米粉末的制备方法如均相共沉淀法，水溶液共沉淀法，电解法，溶胶-凝胶法，喷雾燃烧法，喷雾热分解法等以及ITO磁控溅射靶的现有几种制备工艺进行了综合评述。阐述了各种制备工艺过程和工作原理，比较和分析了各工艺方法的优缺点，并提出了制备高品质ITO粉末及ITO靶的努力方向。     

Indium tin oxide nanosized composite powder prepared using waste ITO target

Indium tin oxide （ITO） nano-particles were prepared directly using waste ITO target, which had been coated by magnetron controlled sputtering. The waste ITO target was cleaned with de-ionized water, and then dissolved in acid, filtrated, neutralized, manipulated through azeotropic distillation and finally dried, and in this way the precursor of indium tin hydroxide was obtained. The nanosized rio composite powder was prepared after the precursor heat-treated at 500℃ for 2 h. TEM images show a narrow distribution of particle size is 5-20 nm and the particle size can be controlled. Its granule has a spherical shape and the dispersion of the particle is well. X-ray diffraction （XRD） patterns indicate the only cubic In2O3 phase in the ITO powder hot-treated at 500℃. The purity of ITO composite powder is 99.9907%. The content of radium within filtrate was detected by using the EDTA titration of determination of indium in the ITO powder and ITO target. Appropriate amount of SnCl4.5H2O was dissolved in the filtrate, and then ITO powder containing 10 wt.% SnO2 was successfully prepared by heat-treating.     

Effect of powder mixing process on the microstructure and thermal conductivity of Al/diamond composites fabricated by spark plasma sintering

Two powder mixing processes, mechanical mixing (MM) and mechanical alloying (MA), were used to prepare mixed Al/diamond powders, which were subsequently consolidated using spark plasma sintering (SPS) to produce bulk Al/diamond composites. The effects of the powder mixing process on the morphologies of the mixed powders, the microstructure and the thermal conductivity of the composites were investigated. The results show that the powder mixing process can significantly affect the microstructure and the thermal conductivity of the composites. Agglomerations of the particles occurred in mixed powders using MM for 30 min, which led to high pore content and weak interfacial bonding in the composites and resulted in low relative density and low thermal conductivity for the composites. Mixed powders of homogeneous distribution of diamond particles could be obtained using MA for 10 min and MM for 2 h. The composite prepared through MA indicated a high relative density but low thermal conductivity due to its defects, such as damaged particles, Fe impurity, and local interfacial debonding, which were mainly introduced in the MA process. In contrast, the composite made by MM for 2 h demonstrated high relative density and an excellent thermal conductivity of 325 W·m-1·K-1, owing to its having few defects and strong interfacial bonding.     

C-diffusion during hot press in the Al2O3-Cr2O3 system

Alumina is an important technological material due to its excellent physical and thermomechanical properties. Binary compositions enhance some of these properties; especially Cr additions significantly increase the mechanical behaviour of pure alumina. It is well known that the sintered bodies of chromium oxide doped-alumina do not become dense when sintering in air because vaporisation and condensation of Cr₂O₃ during the high temperature densification process. The aim of this work is to assess the hot press sintering as an adequate processing method to obtain full dense sintered bodies from well homogeneous powders on chromia-alumina system. Using solutions of the desired nitrates, powders were prepared by the Pechini process in the range 0–6 Cr₂O₃ wt% and hot-pressed at 1500 C. C-diffusion and microstructure of the final densed bodies were studied in order to evaluate synthesis process feasibility.     

工艺参数对Nd:YAG烧结致密化的影响

以高纯Y_2O_3、Al_2O_3和Nd_2O_3粉体为原料,少量纳米SiO_2为烧结助剂,采用真空烧结方法制备致密的Nd:Y_2Al_5O_(12)(Nd:YAG)陶瓷,并研究球磨处理原料粉体、Y_2O_3原料颗粒度和烧结气氛对Nd:YAG烧结致密化的影响.结果表明,机械合金化氧化物混合粉体,可明显细化氧化物颗粒,促进Nd:YAG的烧结.在1600℃保温8h,对球磨20h的粉体压坯真空烧结得到的Nd:YAG块体相对密度达99%,晶粒大小约为10μm;采用纳米Y_2O_3,粉体作真空烧结原料,可提高烧结活性,获得细晶和高致密度的Nd:YAG陶瓷,对混合粉体球磨20h压坯烧结可得到晶粒大小为2μm、相对密度为98.5%的Nd:YAG块体;在氩气保护下常压烧结,得到的Nd:YAG块体组织难以辨认,而且残留许多孔隙.     

Microstructure and properties of indium tin oxide thin films deposited by RF-magnetron sputtering

Tin-doped indium oxide （ITO） thin films were prepared using conventional radio frequency （RF） planar magnetron sputtering equipped with IR irradiation using a ceramic target of In2O3/SnO2 with a mass ratio of 1：1 at various IR irradiation temperatures T1 （from room temperature to 400℃）. The refractive index, deposited ratio, and resistivity are functions of the sputtering Ar gas pressure. The microstructure of ITO thin films is related to IR T1, the crystalline seeds appear at T1= 300℃, and the films are amorphous at the temperature ranging from 27℃ to 400℃. AFM investigation shows that the roughness value of peak-valley of ITO thin film （Rp-v） and the surface microstructure of rio thin films have a close relation with T1. The IR irradiation results in a widening value of band-gap energy due to Burstein-Moss effect and the maximum visible transmittance shifts toward a shorter wavelength along with a decrease in the film＇s refractive index. The plasma wavelength and the refractive index of ITO thin films are relative to the T1. XPS investigation shows that the photoelectrolytic properties can be deteriorated by the sub-oxides. The deterioration can be decreased by increasing the oxygen flow rote （fo2）, and the mole ratio of Sn/In in the samples reduces with an increase info2.     

Fabrication and characterization of ITO thin films on heat-resistant transparent flexible clay films

Transparent conductive indium tin oxide (ITO) thin films were deposited on transparent flexible clay films with heat resistant and high gas barrier properties by rf magnetron sputtering. The electrical, structural, and optical properties of these films were examined as a function of deposition temperature. A lowest resistivity of 4.2 × 10^− 4 Ωcm and an average transmittance more than 90% in the visible region were obtained for the ITO thin films fabricated at deposition temperatures more than 300 °C. It was found that ITO thin films with low resistivity and high transparency can be achieved on transparent flexible clay film using conventional rf magnetron sputtering at high temperature, those characteristics are comparable to those of ITO thin films deposited on a glass substrate.     

Preparation of indium tin oxide targets with a high density and single phase structure by normal pressure sintering process

The present work mainly describes the technology for preparing indium-tin oxide (ITO) targets by cold isostatic pressing (CIP) and normal pressure sintering process.ITO powders were produced by chemical co-precipitation and shaped into an ITO green compact with a relative density of 60% by CIP under 300 MPa.Then,an ITO target with a relative density larger than 99.6% was obtained by sintering this green compact at 1550 ℃ for 8 h.The effects of forming pressure,sintering temperature and sintering time on the...     

热压烧结ITO靶材物相组成与电子结构研究

采用XRD、XPS对ITO固溶烧结前后物相结构及靶材表面In、Sn、O三元素价态进行表征和研究。结果发现:ITO固溶体中溶质与溶剂离子的半径差异较大是引发掺杂后XRD图谱谱峰偏移的主要原因;而XPS图谱中谱峰偏移则是Sn掺杂导致ITO导带中电子态占有率增加、Fermi能级升高的缘故。研究结果为制备成分、结构均匀的高密度ITO靶材提供了有益的参考。     

粉末冶金W/Re合金靶材的显微结构及磁控溅射沉积性能

为了研制高品质W/Re合金靶材,采用机械混料、压制成形和真空烧结致密化工艺路线制备了纯钨及铼含量分别为1％、5％、10％(质量分数)的钨/铼(W/Re)合金,测试了W/Re合金的致密度、晶粒度及晶粒取向、磁控溅射沉积等性能.研究表明,W/Re合金致密度及纯度均随Re含量增加而逐渐提高,而晶粒逐渐细化.W/10％Re合金...     

Study on Nano structured WC Co Composite Powders Made by Mechanical Milling

１ＩｎｔｒｏｄｕｃｔｉｏｎＷＣＣｏｃｏｍｐｏｓｉｔｅｐｏｗｄｅｒｓａｒｅｔｈｅｍａｉｎｒａｗｍａｔｅｒｉａｌｓｆｏｒｐｒｏｄｕｃｉｎｇｃｅｍｅｎｔｅｄｃａｒｂｉｄｅｃｕｔｉｎｇｔｏｏｌｓ．Ｉｎｏｒｄｅｒｔｏｉｍｐｒｏｖｅｔｈｅｉｒｔｏｕｇｈｎｅ...     

高迁移率的钛掺杂氧化铟薄膜在晶硅/非晶硅异质结电池上的应用研究

采用钛掺杂氧化铟旋转靶制备透明导电薄膜应用在晶硅/非晶硅异质结电池上。在不同氧含量下,研究钛掺杂氧化铟薄膜(T100薄膜)的光电性能,同时对比分析ITO薄膜。在电镜下T100薄膜呈现出柱状结构,并且展示出优异的光学性能。T100薄膜最大载流子迁移率可以达到75.6 cm~2·(V·s)^-1。相比于ITO薄膜,T100薄膜具有优异的电学传导和透光率,因此在异质结电池量产线上电池转换效率可以实现0.26%的提升。     

溶胶-喷雾干燥超细/纳米晶W-20Cu复合粉末的烧结行为

采用喷雾干燥-氢气还原法制备超细/纳米晶W-20Cu(质量分数,%)复合粉末,粉末压坯直接从室温推入高温区烧结不同时间后直接取出水淬,研究其烧结致密化和显微组织的变化。结果表明,超细/纳米晶W-20Cu粉末在1000～1200℃烧结时发生迅速致密化。粉末压坯在1200℃烧结60min,其材料致密度已达到96.4%。1420℃烧结90min时致密度达到99%以上。1100～1420℃烧结时其烧结致密化活化能不断减小,从1100℃时的276.3kJ/mol减小到1420℃时的29.1kJ/mol。当温度低于1200℃时,W晶粒长大不明显,当温度超过1300℃时,W晶粒开始有明显长大。随温度的升高W晶粒发生显著球形化,1420℃烧结时发现其晶粒长大符合G3=kt的Ostwald机制,此时晶粒长大动力学系数K仅为0.024μm3/min。     

Effect of processing parameters on the microstructure and thermal conductivity of diamond/Ag composites fabricated by spark plasma sintering

Diamond/metal composites with 50 vol.% diamond have been produced by spark plasma sintering (SPS) using pure Ag as a matrix and diamond particles as reinforcement. Three kinds of powder mixing processes were used to prepare the mixture of diamond/Ag powders: dry mixing without milling medium, wet mixing and magnetic blending. Subsequently, they were all consolidated by SPS at various processing parameters to produce bulk diamond/Ag composites. Then samples were heat treated in order to obtain a higher thermal conductivity. The effect of processing parameters on the morphologies of the mixed powders, the microstructure and the thermal conductivity of the composites were investigated by comparing the experimental data. It reveals that particles were easy to agglomerate and the distribution of mixed powders was inhomogeneous by dry mixing method, and wet mixing method is too complex. The most favorable mixing process is magnetic blending by which the powders can be homogenously mixed and the composites prepared by optimized SPS processing parameters can obtain the highest relative density and the best thermal conductivity among the composites prepared by different processes. The magnetic blending diamond/Ag composites even have a 23% increase in thermal conductivity compared with pure silver sintered by SPS.     

ZrB2-SiC基超高温陶瓷（UHTCs）的反应烧结及SHS粉体制备

用普通反应热压方法（RHP）和反应放电等离子体方法（R-SPS）原位反应制备了ZrB2-SiC，ZrB2-SiC—ZrC，ZrB2-SiC-ZrN，以及ZrB2-SiC-AIN4种复合材料。从密度，物相以及显微结构等方面比较了两种烧结方式之间的差别，对于升温速度较慢的普通热压方法，反应分步进行，显微结构不均匀；对于升温速度快的放电等离子体烧结，原料间的自蔓延反应被点着，反应速度快，显微结构均匀。同时以红外灯的热量为点火源，引发了Zr，Si及B4C间在空气气氛下的自蔓延反应，制备了较纯及粒径约为1μm的活性粉体。     

Characteristics of Cr and Al Powders by High Energy Ball Milling

Characteristics of Cr and Al Powders by High Energy Ball Milling     

Ni/Ti(C,N)包覆粉及其金属陶瓷的制备

采用非均相沉淀-热还原法制备Ni/Ti(C,N)包覆粉,并用该包覆粉经真空烧结制得金属陶瓷。利用扫描电镜、电子能谱、X-射线衍射等手段研究包覆粉的结构形貌及烧结后的微观组织与性能。结果表明:非均相沉淀过程中,非晶态的NiCO3·2Ni(OH)2·2H2O在Ti(C,N)颗粒表面成核并生长;经热还原过程后,NiCO3·2Ni(OH)2·2H2O分解并完全还原成Ni,Ni的平均晶粒尺寸约为50nm;采用包覆粉为原料制备金属陶瓷,有效改善了硬质相和粘结相的分布均匀性,但包覆粉烧结过程中存在晶粒长大现象;金属陶瓷的相成分为纯净的Ti(C,N)与Ni两相;金属陶瓷的综合性能相对于传统工艺制得的金属陶瓷有一定提高。     

放电等离子烧结热处理合成Ti_3SiC_2粉体

采用机械合金化合成TiC和Ti_3SiC_2混合粉体,用放电等离子烧结(SPS)系统对该粉体进行热处理,以合成高纯Ti_3SiC_2粉体.结果表明,采用SPS无压热处理可以促进机械合金化粉体在较低温度转变成高纯Ti_3SiC_2粉体材料.随热处理温度(700～1000℃)的升高,产物中Ti_3SiC_2的含量相应增加,当热处理温度为900 1000℃时,产物中Ti_3SiC_2纯度可达98wt%.