Zn靶与掺铝ZnO靶共溅射制备ZnO:Al薄膜及其性能

采用Zn靶和ZnO(掺2%Al2O3(质量分数))陶瓷靶在玻璃衬底上共溅射沉积Al掺杂ZnO薄膜,即ZnO:Al透明导电薄膜,研究Zn靶溅射功率(0～90 W)和衬底温度(室温、100℃和200℃)对薄膜结构、形貌、光学和电学性能的影响。结果表明:按双靶共溅射工艺制备的ZnO:Al薄膜的晶体结构均为六角纤锌矿结构,且随着Zn靶溅射功率的增加,薄膜的结晶质量呈现出先改善后变差的规律,薄膜中的载流子浓度逐渐升高,电阻率逐渐降低,而薄膜的光学性能受其影响不大;随着衬底温度的升高,薄膜的结晶性能得到改善,薄膜的可见光透过率增强,电阻率降低。     

溶胶-凝胶法制备ZAO薄膜研究

研究了用溶胶-凝胶法制备ZAO薄膜的工艺、掺杂及其显微结构.用六水合氯化铝在溶胶中引入Al2O3.掺杂Al的含量为1%,3%,6%和9%.用浸涂法在石英玻璃基片上浸涂ZnAO薄膜,研究了热处理、掺杂对ZAO薄膜相组成和显微结构的影响.X射线衍射结果表明,衍射图谱中无Al2O3的衍射峰.随着掺杂量的变化,ZnO主要衍射峰的位置、晶面间距均发生了有规律的变化,说明Al掺杂进了ZnO晶格中.研究结果表明,溶胶浓度、Al掺杂量、热处理温度都影响薄膜的显微结构.当薄膜厚度较大时,热处理过程中ZnO晶粒呈现明显的择优生长现象.     

溶胶-凝胶法制备ZAO薄膜研究

研究了用溶胶．凝胶法制备ZAO薄膜的工艺、掺杂及其显微结构。用六水合氯化铝在溶胶中引入Al2O3。掺杂Al的含量为1％，3％，6％和9％。用浸涂法在石英玻璃基片上浸涂ZnAO薄膜，研究了热处理、掺杂对ZAO薄膜相组成和显微结构的影响。X射线衍射结果表明，衍射图谱中无Al2O3的衍射峰。随着掺杂量的变化，ZnO主要衍射峰的位置、晶面间距均发生了有规律的变化，说明Al掺杂进了ZnO晶格中。研究结果表明，溶胶浓度、Al掺杂量、热处理温度都影响薄膜的显微结构。当薄膜厚度较大时，热处理过程中ZnO晶粒呈现明显的择优生长现象。     

Sb2O3/CeO2共掺杂ZnO薄膜的研究

采用射频磁控溅射技术制备Sb2O3/CeO2共掺杂ZnO薄膜,研究了薄膜的结构及紫外光吸收性能.结果表明:Sb2O3和CeO2共同掺入ZnO薄膜后,ZnO(002)晶面的XRD衍射峰强度明显下降,ZnO薄膜呈混晶方式生长;共掺杂ZnO薄膜的紫外吸收性能明显优于纯ZnO薄膜,Sb对掺杂ZnO薄膜的结构和紫外吸收性能的影响...     

Ag-Al共掺杂ZnO薄膜的结构及其光学性能的研究

采用溶胶-凝胶工艺在普通玻璃基片上制备了Ag+、Al3+共掺Zno薄膜,通过XRD、紫外分光光度计和金相显微镜等设备,研究了掺杂Ag和Al对半导体ZnO薄膜组织结构和光学性能的影响.结果表明,掺杂Ag和Al对ZnO薄膜结构和光学性能的影响因浓度不同而有差异.Ag+、Al3+掺杂浓度为1%时,摩尔比为4:1;固定Ag+浓度为1.5%,Al3+浓度为0.5%;Ag+、Al3+浓度为3%,摩尔比为4:1,提拉次数15次时,ZaO薄膜的结构、透光率最好.     

溶胶-凝胶法制备纳米ZnO多孔薄膜

以聚乙二醇(polyethylene glycol,PEG)为模板剂,醋酸锌(Zn(Ac)2·2H2O)为原料,二乙醇胺为络合剂,通过溶胶-凝胶法在玻璃基片上制备了纳米ZnO多孔薄膜.利用SEM,IR,TG-DTA等对薄膜的特性进行了表征;探讨了样品在溶胶-凝胶及煅烧过程中的物理化学变化;讨论了Zn的浓度、PEG加入量、热处理等对薄膜性能的影响.结果表明,当Zn的浓度为0.6 mol/L,加入0.5 g PEG2000,将溶胶50℃水浴以及在合适的热处理条件下,最终可制得具有一定多孔结构的ZnO薄膜.     

铝掺杂对ZnO:Al薄膜结晶性能与微观组织的影响

以二水合醋酸锌为原材料,采用溶胶-凝胶浸涂法在钠钙玻璃基片上制备了具有c轴择优取向的ZnO:Al薄膜,考察了铝掺杂浓度对薄膜结晶性与微观组织结构的影响.结果表明:铝掺杂使ZnO薄膜(002)晶面的2θ向高角度方向偏移,c轴择优取向性增强,晶粒变小(15～20 nm).当铝掺杂浓度(摩尔分数)为1%～2%时,微观组织结构变得致密均匀;当铝掺杂浓度大于2%时,发生颗粒团聚现象;在高掺杂浓度下(5%和8%),出现大尺寸片状ZnO:Al晶粒异常长大,生长出特殊形貌的薄膜.     

Al-Ag弱掺杂ZnO薄膜的结构和光学特性

采用溶胶凝胶法制备了Al-Ag共掺杂的ZnO薄膜,研究了该ZnO薄膜的表面形貌、微结构和光学性质。结果表明,通过改变Al、Ag掺杂量与Zn的比值,ZnO薄膜呈现出良好的C轴取向。     

电化学沉积法制备Co-ZnO薄膜及其室温铁磁性

摘 要:用电化学沉积方法,在锌片上成功制备出了Co掺杂ZnO稀磁半导体薄膜.XRD研究表明,Co-ZnO薄膜均为六方纤锌矿结构,没有出现与Co相关的杂质相.由XPS测量结果可知,钴离子在ZnO薄膜中以+2价的形式存在,替换了ZnO晶格中部分Zn2+.通过样品室温铁磁性测量结果进一步验证了Co2+取代了ZnO晶格中Zn2+的格位.     

不同氧源对原子层沉积ZnO薄膜的性能影响

采用原子层沉积方法(ALD)分别以H2O、H2O2和O3为氧源制备ZnO薄膜,研究不同氧源对ZnO薄膜生长速率、成分、晶体结构及电学性能的影响.结果表明,采用不同氧源均能实现ZnO薄膜的ALD自限制生长,所制备ZnO薄膜均具有垂直于衬底表面的c轴择优取向.与采用H2O2和H2O为氧源制备的ZnO薄膜相比,XRD和XPS测试证实O3为氧源制备薄膜的晶体质量和Zn/O原子较高;相应的Hall测试表明其电阻率最低为0.053 Ω·cm,此时载流子浓度为4.8×1018 cm-3,Hall迁移率为24.5 cm2/Vs.     

Properties of Ni doped and Ni-Ga co-doped ZnO thin films prepared by pulsed laser deposition

ZnNiO and Zn(Ni,Ga)O thin films were prepared on glass substrates by pulsed laser deposition. The obtained films are of good crystal quality and have smooth surfaces, which have a hexagonal wurtzite ZnO structure with a highly c-axis orientation without any Ga or Ni related phases. Hall-effect measurements showed that the ZnNiO film is n-type, in which the carrier concentration would be greatly enhanced by the addition of Ga. Room temperature ferromagnetism is observed for the ZnNiO and Zn(Ni,Ga)O films. The addition of Ga into the ZnNiO films increases the electron concentration but weakens the room temperature ferromagnetism.     

Effect of defect complex on magnetic properties of (Fe,Mn)-doped ZnO thin films

We have observed room temperature ferromagnetism in Mn-doped and (Fe, Mn)-codoped ZnO thin films grown under different oxygen partial pressures by pulsed laser deposition. The X-ray diffraction and optical transmission spectra studies demonstrate the natural incorporation of Fe and Mn cations into wurtzite ZnO lattices. The effects of transition metal doping and defects on the magnetic properties was investigated. It is found that room temperature ferromagnetism is sensitive to oxygen vacancy and Zn vacancy. The absence of ferromagnetism in pure ZnO films grown under different oxygen partial pressures reveals that the transition metal ions should also play an important role in inducing the ferromagnetism.     

电气石衬底温度对ZnO薄膜的结晶特征和光学特性的影响

利用超声雾化热解技术 (USP) 在不同温度的电气石和玻璃衬底上生长ZnO纳米片状薄膜。结构研究表明晶体为六方纤锌矿多晶结构。衬底温度越高,Raman特征峰越强,XRD结果给出（002）优势定向越明显,晶体结晶性能越好,晶粒尺寸越大。SEM图像显示片状ZnO晶体沿平行衬底方向叠加形成花状晶柱的微观形貌,沉积温度越高,晶柱宽度越大。UV-Vis表明电气石衬底上ZnO吸收峰强度高于玻璃衬底,最大吸收峰位置发生红移,高温下移动更大。     

Growth of nitrogen-doped p-type ZnO thin films prepared by atomic layer epitaxy

Nitrogen-doped, p-type ZnO thin films were grown successfully on sapphire (0001) substrates by using atomic layer epitaxy (ALE). Zn(C2H5)2[Diethylzinc,DEZn], H2O and NH3 were used as a zinc precursor, an oxidant and a doping source gas, respectively. The lowest electrical resistivity of the p-type ZnO films grown by ALE and annealed at 1000 ℃ in an oxygen atmosphere for 1 h was 18.3 Ω·m with a hole concentration of 3.71×1017cm-3 . Low temperature-photoluminescence analysis and time-dependent Hall measurement results support that the nitrogen-doped ZnO after annealing is ap-type semiconductor.     

Eu掺杂ZnO薄膜与Si(100)衬底间扩散过程分析

利用雾化热解工艺,在Si(100)衬底上制备了Eu掺杂的ZnO薄膜,通过N2的作用,将前驱体溶液输送到衬底表面,同时为实现ZnO的晶化,衬底温度保持在350℃.通过RBS分析了薄膜和衬底之间的原子分布,结果显示了ZnO薄膜与Si衬底之间存在过渡层.对RBS数据的分析表明该过渡层的形成是由于Si向ZnO层中的扩散,表明Si向氧化物中的扩散是不能忽略的,即使在350℃的低温下.同时,作者利用Fick扩散方程对Si向Eu3 掺杂ZnO薄膜的扩散行为进行了分析,结果表明掺杂离子Eu3 具有阻止Si扩散的能力,其原因可能与Eu3 离子在晶界上的偏析有关.     

Effects of Nitridation Temperature on Characteristics of Gallium Nitride Thin Films Prepared Via Two-Step Method

In this research,the growth of GaN thin films on c-plane sapphire(0001) substrates via two-step method without the assist of buffer layer and catalysts was demonstrated.First,gallium oxide(Ga_2O_3) thin films were deposited on sapphire substrates by radio frequency magnetron sputtering method.The deposited Ga_2O_3 thin films were then nitridated at various temperatures.In this research,attention is focused on the influence of nitridation temperatures on the structural and optical properties of the synthesized GaN thin films.It is revealed that 950 ℃ is the optimal nitridation temperature for synthesizing hexagonal wurtzite GaN thin film with preferential(0002) growth direction.     

Room temperature ferromagnetism of Si-doped ZnO thin films prepared by sol–gel method

Pure ZnO and Si-doped ZnO thin films were deposited on quartz substrate by using sol-gel spin coating process. X-ray diffraction analysis shows that all the thin films have hexagonal wurtzite structure and preferred c-axis orientation. Si-doped ZnO films show room temperature ferromagnetism (RTFM) and reach the maximum saturation magnetization value of 1.54 kAm-1 at 3% Siconcentration. RTFM of Si-doped ZnO decreases with the increasing annealing temperature because of the formation of SiO 2 . Photoluminescence measurements suggest that the RTFM in Si-doped ZnO can be attributed to the defect complex related to zinc vacancies V Zn and oxygen interstitials Oi .     

Grain boundary defects-mediated room temperature ferromagnetism in Co-doped ZnO film

Zn_0.97Co_0.03O films with and without ZnO buffer layer have been fabricated by magnetron sputtering to investigate the role of grain boundary defects in ferromagnetic ordering in this system. The deposited wurtzite films with (0 0 2) preferred orientation all show intrinsic room temperature ferromagnetism based on the substitutional behavior of Co²⁺. We found that the ZnO/Co:ZnO film grows in smaller grain size, compared with Co:ZnO film, which leads to the increase in grain boundary defects. Meanwhile the increase in oxygen vacancies is confirmed by Co K-edge X-ray-absorption near-edge spectra and the enhancement of saturated magnetization is observed in ZnO/Co:ZnO film. Hence the most important factor for mediating ferromagnetism is proposed to be grain boundary defects, i.e., oxygen vacancies. Bound magnetic polaron mechanism is adopted to explain the intrinsic origin and the mediative effects of grain boundary defects on ferromagnetism in Co-doped ZnO films.