偏压对阴极电弧离子镀AIN薄膜的影响

在不同基体负偏压作用下,用阴极电弧离子镀等离子体物理气相沉积（PVD）方法在单晶Si(100）基片上获得六方晶系的晶态AIN薄膜。用X射线衍射仪分析了沉积膜的物相组成和晶格位向随偏压的变化。在扫描电子显微镜（SEM）下观察沉积膜的显微组织形貌。结果表明,在较小偏压下,AIN膜呈（002）择优取向,表面致密均匀;在较大偏压下,AIN膜呈（100）择优取向,表面形貌则粗糙不平,AIN薄膜的择优取向及表面形貌受到不同偏压下不同离子轰击能量的影响。     

薄膜厚度对Au/ZnO/n+-Si薄膜压敏电阻器阈值电压的影响

本文采用直流磁控溅射法和多次沉积与掩膜技术,在n+Si(100)衬底上制备了一系列厚度不同的ZnO薄膜,表面镀Au的探针与ZnO/n+-Si构成了一系列ZnO层厚不同的Au/ZnO/n+-Si薄膜压敏电阻器.利用X射线衍射确定沉积的ZnO薄膜为高度c轴(0002)取向的晶体薄膜,利用紫外-可见透射光谱对沉积的ZnO薄膜...     

脉冲激光沉积制备立方AlN薄膜的研究

采用脉冲激光沉积(PLD)方法,在SrTiO3(100)衬底上在650℃、10Pa N2条件下成功制备了立方结构的AlN薄膜.高能电子衍射(RHEED)及X射线衍射(XRD)分析表明立方AlN和SrTiO3的外延关系为AlN[100]∥SrTiO3[100]和AlN(200)∥SrTiO3(100).其AlN(200)衍射峰的摇摆曲线半高宽(FWHM)为0.44°,说明薄膜结晶性能良好.原子力显微镜(AFM)表明外延的立方AlN薄膜表面具有原子级平整度,其表面均方根粗糙度(RMS)为0.674nm.通过X光电子能谱(XPS)分析AlN薄膜表面成分,结果表明AlN薄膜表面没有被氧化.     

Pb(Zr,Ti)O3薄膜微区残余应力的X射线面探扫描分析

根据在X射线二维衍射几何关系下建立的应力应变方程,提出了一种基于X射线多晶面探衍射仪系统分析射频磁控溅射制备的Pb(Zr,Ti)O3薄膜微区残余应力的测量方法,即通过基于X射线衍射圆锥形变的分析来表征薄膜的残余应力,试验结果表明薄膜所受为残余拉应力,同时利用X射线面探扫描方法评价了薄膜的残余应力分布.     

X射线衍射技术在薄膜残余应力测量中的应用

残余应力测量在薄膜材料研究中具有重要的意义,综述了薄膜残余应力X射线衍射技术测量的研究现状,其中介绍了强织构薄膜残余应力X射线衍射测量技术;同时对由于G(o)bel平行光镜、毛细管元件及二维探测器等X射线功能附件的发展,以及同步辐射源X射线的应用而带来残余应力分析的新进展进行了介绍.     

用平面磁控溅射低温生长C轴择优取向的AIN薄膜

本文介绍了用 x-射线衍射仪、扫描电镜和透射电镜来分析用直流平面磁控溅射法在载波片上生长的 AIN 薄膜的结构,结果表明 AIN 薄膜的(002)晶面与基片表面平行,迴摆曲线分析得出标准偏差σ≈0.7°,俄歇谱分析结果表明制得的 AIN 薄膜是高纯的。这种方法适于制取 C轴高度择优取向 AIN 薄膜。     

离子束辅助沉积TiN薄膜的结构和成分

用离子束辅助沉积合成了TiN薄膜,背散射、X射线衍射和透射电镜实验的结果表明,在本实验条件下,薄膜Ti/N比接近于TiN的化学计量比,和氮离子束流密度无关。薄膜存在<100>择优取向,在一定条件下,可以形成只有(100)取向的TiN薄膜。     

不同浓度的Mg掺杂β-Ga2O3薄膜的制备与研究

本文采用射频磁控溅射方法在石英和高阻硅衬底上制备纯 β-Ga2O3薄膜和不同掺杂浓度的Mg掺杂β-Ga2O3薄膜,研究了薄膜的结构、光学和电学性质.X射线衍射测试结果表明,在我们的掺杂浓度内,Mg掺杂β-Ga2O3薄膜没有出现其他晶相的衍射峰,随着Mg掺杂浓度变大,薄膜的(401)和(601)衍射峰强度变弱.使用X射线...     

MOCVD法在MgO(100)衬底上生长m面ZnMgO薄膜

本文采用金属有机化学气相沉积(MOCVD)法在MgO(100)衬底上成功生长了非极性的m面(1010)ZnMgO薄膜。研究了衬底温度对ZnMgO薄膜生长取向的影响。X射线衍射(XRD)分析结果表明当衬底温度为400℃时可以获得单一取向的m面ZnMgO薄膜。采用扫描电子显微镜(SEM)观察到ZnMgO薄膜表面平整,由条纹状结构组成。透射电子显微镜(TEM)分析进一步证明ZnMgO为具有m面取向的单晶薄膜。X射线光电子能谱(XPS)定量分析表明ZnMgO薄膜中Mg含量为3at.%。     

Zr/Nb薄膜材料的制备及界面结构研究

通过直流磁控溅射法在单晶Si(100)基底上制备了Zr/Nb/Si薄膜材料。X射线衍射(XRD)研究表明Zr薄膜以多晶形式存在,而Nb薄膜则形成了(110)晶面择优生长。薄膜中Zr和Nb晶粒大小分别为14,6 nm。扫描电镜研究表明形成的薄膜表面平整光滑,没有微裂纹存在。扫描俄歇电子能谱及X射线光电子能谱的研究表明,Zr/Nb/Si薄膜样品具有清晰的界面结构。在薄膜表面形成了致密的氧化层物种,而在膜层内部少量氧则以吸附态形式存在。     

Effect of negative bias voltage on the microstructures of AlN thin films fabricated by reactive r.f. magnetron sputtering

Aluminium nitride thin films have been fabricated on silicon wafers by reactive r.f. magnetron sputtering in mixed Ar-N2 discharge with variation of negative bias voltage. The effect of negative bias voltage on the microstructures of AlN thin films have been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), stress measurement, Auger electron spectroscopy (AES), etc. While the negative bias voltage was varied in the range 0 to −45 V, highly c-axis oriented film can be fabricated at −30 V, and the grain size and compressive stress increase with the negative bias voltage. From the plasma analysis, the dominant positive chemical species is identified as N+2 ions. The above results can be understood considering that at the kinetic energy transfer and flux of N+2 ions increase with increasing negative bias voltage. This revised version was published online in August 2006 with corrections to the Cover Date.     

Pulsed Laser Deposition of YBa2Cu3O7 Superconducting Film on MgO Templates Spray Pyrolyzed on Hastelloy C276

Pulsed laser deposition (PLD) was used to deposit YBCO on MgO-buffered C276 substrates in order to evaluate the quality of the deposited MgO films which were deposited by spray pyrolysis. The characterization of the thin films was done using scanning electron microscopy, atomic force microscopy, electron backscattered diffraction, X-ray diffraction 2??-scans, rocking curve (??-scans), phi scan, pole-figure measurements, and AC susceptibility. It was found that c-axis oriented YBCO films were grown on c-axis oriented MgO films which confirm that the deposited YBCO films copied the out-of-plane texture of the spray pyrolyzed MgO buffer. However, MgO and YBCO films have a very weak in-plane texture. The AC susceptibility measurements show that the YBCO films have a broad superconducting transition temperature which may be attributed to the weak in-plane texture.     

氮化碳薄膜的结构与特性

采用射频等离子体增强化学气相沉积（ＣＶＤ）＋负偏压热丝辅助方法直接在Ｓｉ（１００）衬底上制备了多晶Ｃ_３Ｎ_４薄膜．Ｘ射线衍射测试表明,薄膜同时含有α－和β-Ｃ_３Ｎ_４晶相以及未知结构,没有观测到石墨衍射峰．利用扫描电子显微镜观测到线度约２μｍ、横截面为六边形的β－Ｃ_３Ｎ_４晶粒．纳米压痕法测得薄膜的硬度达７２．６６ ＧＰａ．     

SAW器件用金刚石基c轴取向LiNbO3压电薄膜的制备

采用脉冲激光沉积技术,在以c轴取向ZnO作为缓冲层的金刚石/硅基底上制备出了结晶良好的高c轴取向LiNbO3薄膜。利用X射线衍射对薄膜的结晶质量和c轴取向性进行了研究,结果表明制得的LiNbO3薄膜具有高度c轴取向且结晶质量良好。采用扫描电子显微镜和原子力显微镜对薄膜的表面形貌进行了分析,发现薄膜表面光滑,晶粒尺寸均匀,薄膜表面粗糙度约为20nm。     

Preferred crystal orientation of sol-gel-derived Bi4-xLaxTi3O12 thin films on silicon substrates

Polycrystalline thin films of La-substituted bismuth titanate (BLT) were formed directly on p-type Si(100) substrates by using sol-gel and spin coat methods. The BLT film and interfacial layer between BLT and Si were quantitatively investigated by the X-ray reflectivity method. Also, crystal orientations of sub-100-nm-thick BLT thin films were confirmed by X-ray diffraction using a synchrotron radiation source. The preferred c-axis orientation normal to the surface depended on the crystallization temperature. The difference in the preferred c-axis orientations of the BLT films caused the difference in the hysteresis voltage width in the capacitance-voltage characteristics of Au/BLT/p-Si structures. Furthermore, the c-axis of the Bilayered structure was preferentially oriented and aligned in the in-plane direction.     

MOD法制备的Bi3.25Nd0.75Ti3O12薄膜的铁电各向异性行为

采用金属有机分解法(MOD)在(111)Pt／Ti／SiO2／Si衬底上制备了含(117)成分的c轴择优取向和α轴择优取向的Bi3.25Nd0.75Ti3O12(BNT)薄膜．实验发现，BNT薄膜的品型结构主要依赖于预退火条件．电学性能测试表明，α轴择优取向的BNT薄膜具有高的剩余极化和矫顽场，较高的介电常数和介电损耗，以及较大的电容调谐率；而c轴择优取向的则相反．BNT薄膜具有同Bi4Ti3O12(BIT)薄膜相似的铁电各向异性行为．     

PZT/ZnO薄膜制备及其结构特性研究

利用固相反应制备的ZnO-Li_(2.2%)陶瓷靶和RF射频磁控溅射技术在Si(100)基片上制备了高度c轴择优取向的ZnO薄膜,XRD和电性能分析表明掺杂Li离子改善了ZnO靶材的结构和性能,同时研究了不同RF溅射温度对ZnO薄膜结构与取向的影响;然后采用sol-gel前驱单体薄膜制备方法,以ZnO为过渡层淀积PZT薄膜,探讨高度c轴(002)择优取向ZnO薄膜对PZT薄膜结构与性能的影响,实验发现在PZT/ZnO异质结构中,致密、均匀和高度c轴择优取向的ZnO可作为晶核,促进PZT钙钛矿结构转化、晶粒(110)择优取向生长,相应降低PZT薄膜的退火温度.     

Deposition of c-axis orientation aluminum nitride films on flexible polymer substrates by reactive direct-current magnetron sputtering

Aluminum nitride (AlN) piezoelectric thin films with c-axis crystal orientation on polymer substrates can potentially be used for development of flexible electronics and lab-on-chip systems. In this study, we investigated the effects of deposition parameters on the crystal structure of AlN thin films on polymer substrates deposited by reactive direct-current magnetron sputtering. The results show that low sputtering pressure as well as optimized N₂/Ar flow ratio and sputtering power is beneficial for AlN (002) orientation and can produce a highly (002) oriented columnar structure on polymer substrates. High sputtering power and low N₂/Ar flow ratio increase the deposition rate. In addition, the thickness of Al underlayer also has a strong influence on the film crystallography. The optimal deposition parameters in our experiments are: deposition pressure 0.38 Pa, N₂/Ar flow ratio 2:3, sputtering power 414 W, and thickness of Al underlayer less than 100 nm.     

热退火对射频反应溅射氮化铝薄膜场电子发射的影响

以氮气为反应气体;用射频反应溅射方法制备了ＡＩＮ薄膜,结合ＸＰＳ和ＸＲＤ表征考察了热退火后处理对样品场电子发射性能的影响．实验表明,热退火是改善样品场发射稳定性的有效途径,样品经７００℃退火后,发射电流的涨落从未退火前的１３５μＡ下降到２０μＡ;并且发射的开启电压、发射电流的涨落和滞后等对退火温度表现出强烈的依赖性．文中认为,退火处理造成了薄膜结构的变化,引起表面电子亲和势特性以及电导特性的改变,进而影响了其发射特性     

Effect of rapid thermal annealing on the crystal quality and the piezoelectric response of polycrystalline AlN films

This work analyzes the effect of post-deposition rapid thermal annealing (RTA) on the crystal quality and the piezoelectric response of sputtered polycrystalline aluminium nitride (AlN) thin films. AlN films with mixed crystal texture were not significantly affected by RTA processing. However, in films exhibiting clear c-axis preferred orientation, the annealing produced a crystallization process, characterized by an increase in the grain size of the original crystallites, the growth of new small grains, and the reduction of defects. The improvement in the crystal quality was more evident in highly textured c-axis oriented films. However, the enhanced crystal quality of the films due to RTA was not accompanied by a significant improvement in the piezoelectric response. This is attributed to the presence of grains with opposite polarities that could not be rearranged through the RTA treatment.