荷能离子束沉积的氧化物膜光学性质

报道在不加热的基底上,由双离子束溅射或离子辅助的电子束蒸发技术制的ＺｒＯ２和ＴｉＯ２单摹光学性质,并提供卫工艺参数和离子束设备的说情。这两种荷 能离子束工艺已被用于光学多层膜,如减反射膜和短波通滤光片的制备     

荷能离子束沉积的氧化物薄膜光学性质

报道在不加热的基底上,由双离子束溅射或离子辅助的电子束蒸发技术制造的ＺｒＯ２ 和ＴｉＯ２ 单层薄膜的光学性质,并提供了工艺参数和离子束设备的详情。这两种荷能离子束工艺已被用于光学多层膜,如减反射膜和短波通滤光片的制备。     

高色散系数线性渐变滤光片的研制

采用双离子束溅射物理沉积方法,通过修正线性渐变沉积速率制备了高透过率、高色散系数的线性渐变滤光片。在不同材料的膜厚修正过程中,通过匹配高低折射率材料的线性渐变趋势来减小两种材料的失配误差。利用微小光斑测试方法获得了线性渐变滤光片的线性渐变光谱数据,使用扫描电子显微镜表征了滤光片的表面形貌及微观结构。测试结果表明:制备的线性渐变滤光片各个位置的中心波长峰值透过率均达到85%以上,其工作波长为650~1 050nm,中心波长的线性变化率为20nm/mm,线性度误差在5nm以内,带外截止度在0.1%以下。制备的线性渐变滤光片不仅具有好的光谱特性,也具有良好的稳定性,完全满足滤光片在空间应用时对小型化、集成化和稳定性的需求。     

离子束溅射制备“日盲”紫外诱导透射滤光片

对“日盲”紫外诱导透射滤光片进行了理论设计与分析,并分别优化了离子束溅射法沉积ZrO2、SiO2和Al薄膜的工艺.利用反射与透射光谱反演获得了ZrO2和SiO2薄膜的光学常数,并由JGS1/SiO2/Al/SiO2/air (SAS)样品的变角度椭偏光谱反演精确获得了Al薄膜的光学常数.在此基础上,采用离子束溅射沉积方...     

用离子束溅射法制备长波段X射线多层膜

叙述了用离子束溅射镀膜机ＯＸＦＯＲＤ进行Ｘ射线长波段多层膜实验及制备Ｘ射线多层膜光学元件方面的工作。简述离子束溅射镀膜机的工作原理,Ｘ射线多层膜的制备过程,主要工艺参数,以及用Ｘ射线小角衍射仪对制备样品周期结构的检测和用软Ｘ射线反射率计测反射率的部分结果。     

长波红外光学薄膜器件研究

论述了长波红外滤光片制备中膜系设计、监控方案设计、工艺条件等主要技术。列举了允差分析在优选膜系、改善膜厚监控中的具体应用。并以长波红外重要高折射率材料碲化铅为例,描述了研究膜层材料特性及确定重要工艺条件—基板温度的试验方法及结果     

用离子束溅射法制备长波段X射线多层膜

叙述了用离子束溅射镀膜机ＯＸＦＯＲＤ进行Ｘ射线长波段多层实验及制备Ｘ躬一多层膜光学元件方面的工作。简述离子束溅射镀膜机的工作原理,Ｘ射线多摹制备过程,主要工艺参数,以及用Ｘ射线小角衍射仪对制备样品周期结构的检测和用软Ｘ射线反射率计测反射率的部分结果。     

长波红外光学薄膜器件研究

论述了长波红外滤光片制备中膜系设计、监控方案设计、工艺条件等主要技术。列举了允差分析在优选膜系、改善膜厚监控中的具体应用。并以和菠 红外重要高折射率材料碲化铅为例,描述了研究膜赤道主确定重要工艺条件－－基板温度的试验方法及结果。     

6.5～14μm红外长波通滤光片正面膜系的研制

采用了规整膜系作为6．5-14μm红外长波通滤光片正面膜系的初始膜系,针对规整膜系中存在较大通带波纹的现象,利用Macleod光学薄膜分析软件有选择地对部分膜层进行优化。根据优化后的膜系设计结果,采用热电阻真空蒸发镀膜工艺镀制。光谱测试表明,膜系在6．5～14μm工作波段的通带波纹平坦,平均透过率达到88．5％,在3～5．5μm截止范围内Tmax〈0．2％,并具有很好的截止带边缘陡度。该膜系具有工艺简单,膜厚监控易于操作的特点,适用于工业大规模生产。     

高能离子束辅助沉积制备钛纳米膜

用离子束溅射沉积和高能离子束辅助沉积方法制备了具有择尤性的钛纳米薄膜,并采用原子力显微镜、X射线衍射仪和俄歇电子谱仪研究了试样表面预处理、离子束流和温度等离子束工艺参数对钛薄膜结构的影响。结果表明：离子束溅射沉积的钛膜在[002]和[102]晶向上呈现出明显的择尤生长现象,并分别在该两个晶向上表现出纳米晶型和非纳米晶型结构;当用高能离子束辅助沉积时,[102]晶向择尤生长现象消失,且钛膜的结构对束流变化较为敏感,束流较低时,钛膜为纳米结构且择尤生长现象减弱,而束流增加时晶粒长大,择尤生长现象叉增强。另外钛膜容易受到氧的污染,并随辅助离子强度增加而增强。     

Evaluation of surface roughness and nanostructure of indium tin oxide (ITO) films by atomic force microscopy

Indium tin oxide was deposited on a glass (soda lime glass) by radiofrequency sputtering system at different sputtering gas (argon/oxygen 90/10%) pressures (20-34 mTorr) at room temperature. The sputtering rate was affected by the sputtering gas pressure. The optimum sputtering gas pressure was found to be 27 mTorr. The samples at different thicknesses (168, 300, 400, 425, 475, 500 and 630 nm) were deposited on the substrate. Transparency, electrical conductivity and surface roughness of the films were characterized. The samples were annealed at 350, 400 and 450 degrees C to evaluate annealing process effects on the concerned parameters and, therefore, the above-mentioned measurements were repeated again. The films exhibited reasonable optical transmittance and electrical conductivity and greatly improved after annealing. The characterization was focused on the scanning of the film surfaces before and after annealing, which has a prominent effect on the optical properties of the films. Film surfaces were scanned by scanning probe microscopy in contact atomic force mode. The most consideration was devoted to image analysis.     

Study on the c-axis preferred orientation of ZnO film on various metal electrodes

ZnO thin film was deposited on various metal electrodes by reactive sputtering, and c-axis preferred orientation of the film has been studied. ZnO, which has high piezoelectricity, is promising for oscillators or filter devices such as surface acoustic wave (SAW) device, gas sensor, and film bulk acoustic resonator (FBAR). But, for the application of ZnO film for these devices, the film should be grown with c-axis normal to the electrode. In this study, Pt, Al, and Au were deposited on Si wafer, and the surface roughness and crystal structure of the ZnO film on the electrode were investigated using AFM, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Columnar structures of ZnO films were grown with c-axis normal to all electrodes, and among them Pt electrode showed the highest preferred orientation of ZnO film.     

Study on the c-axis preferred orientation of ZnO film on various metal electrodes

ZnO thin film was deposited on various metal electrodes by reactive sputtering, and c-axis preferred orientation of the film has been studied. ZnO, which has high piezoelectricity, is promising for oscillators or filter devices such as surface acoustic wave (SAW) device, gas sensor, and film bulk acoustic resonator (FBAR). But, for the application of ZnO film for these devices, the film should be grown with c-axis normal to the electrode. In this study, Pt, Al, and Au were deposited on Si wafer, and the surface roughness and crystal structure of the ZnO film on the electrode were investigated using AFM, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Columnar structures of ZnO films were grown with c-axis normal to all electrodes, and among them Pt electrode showed the highest preferred orientation of ZnO film.     

Note: innovative demodulation scheme for coherent detectors in cosmic microwave background experiments

We propose an innovative demodulation scheme for coherent detectors used in cosmic microwave background polarization experiments. Removal of non-white noise, e.g., narrow-band noise, in detectors is one of the key requirements for the experiments. A combination of modulation and demodulation is used to extract polarization signals as well as to suppress such noise. Traditional demodulation, which is based on the two-point numerical differentiation, works as a first-order high pass filter for the noise. The proposed demodulation is based on the three-point numerical differentiation. It works as a second-order high pass filter. By using a real detector, we confirmed significant improvements of suppression power for the narrow-band noise. We also found improvement of the noise floor.     

应力变化对多层薄膜窄带滤光片透射光谱的影响

利用薄膜应力公式和弹性力学的小挠度弯曲理论分析了在应力变化情况下,多层薄膜应变与膜厚变化的关系,并建立其数学模型,提出多层薄膜各层厚度变化的不均匀性理论.利用这个模型在应力减小200MPa条件下对138层4腔的100GHz滤光片光谱进行了模拟,与设计值比较发现中心波长增加了0.562nm;0.5dB处的带宽比设计值减小0.124nm;25dB处的带宽比设计值减小0.01nm;谱线矩形化变差;插损也有明显的增加.说明了应力变化引起的光学薄膜厚度变化的不均匀性是引起这种窄带干涉滤光片光谱退化的主要原因之一.实验结果为100GHz的窄带滤光片热处理后中心波长增加0.325nm;0.5dB处带宽减少0.01nm;20dB处带宽增加0.014nm;插损增加,谱线通带变形严重,纹波增大,光谱退化了.实验结果与理论分析一致.     

Microstructure and Magnetic Properties of Sputtered Co5 Sm Films

Co5Sm/Cr bilayer films were deposited on Si and glass slides by means of a Direct-Current(DC)magnetron sputtering system with substrate heating.Magnetic properties measurements show that the sample with glass substrate has a comparatively large coercivity(Hc=2 141.2 Oe)with a relatively low optimal temperature(Ts=350 ℃).X-ray diffraction patterns indicate that Cr presents a hexagonal-close-packed(hcp)texture on Si,while a body-centered-cubic(bcc)structure on glass substrate,which leads to Co5Sm films having different lattice constants on Si and glass substrates.At their optimal temperature,the grain size of the sample on glass slide is smaller with its size distribution more uniform.Concurrently,the shape of magnetic domain is more regular and ordered.The value of magnetic switching volume(V)for the film on glass is 1.65×10-18 cm3,smaller than that for films on Si.For the film on glass,the magnetization reversal mechanism is mainly influenced by magnetocrystalline anisotropy,the shape of the crystal grain and the stress in the film.     

柔性声表面波器件的波模式分析

用反应磁控溅射法在柔性聚酰亚胺衬底上沉积了ZnO压电薄膜,并制备了基于ZnO压电薄膜的柔性声表面波(SAW)器件。制备的柔性SAW器件显示了良好的谐振性能,而且展现出两个波模式:模式0和模式1。当波长为32μm,ZnO厚度为4μm时,SAW器件的模式0和模式1的谐振频率分别为34.4MHz和158.5MHz,对应声速为1 100.8m/s和5 072m/s。模式0为已知的瑞利波,模式1为新的高频模式。沉积了不同厚度的ZnO薄膜制备柔性SAW器件,进一步分析了薄膜厚度对SAW器件和模式1的影响。分析认为该高频模式不是传统硬质衬底上SAW器件产生的Sezawa波,而是S_0兰姆波,并且是有衬底情况下的S_0兰姆波。文中还采用Comsol仿真分析了新的高频模式1的粒子振动位移,结果和S_0兰姆波粒子振动位移一致,从而验证了其为广义兰姆波的正确性。     

Surface characteristics and tribology study of metal oxide thin films

Abstract

Microcrystalline high quality undoped ZnO thin films were deposited on Si(100) and Corning 1737F glass substrates by a dc magnetron sputtering system. Surface and mechanical properties of ZnO thin films deposited under different deposition conditions (thickness, deposition rate and plasma composition) were investigated. Atomic force microscopy, nanoindentation techniques and scratch tests have been carried out. The lateral grain radius was between 50 and 160 nm. Surface roughness was found to vary from 1·3 to 10·3. In order to measure the real hardness of ZnO thin films grown on Si(100) and glass Continuous Stiffness Measurement technique was used. The hardness was found to be between 11 and 13 GPa for the polycrystalline ZnO almost five times larger than for the corresponding single crystalline material, while scratch tests verified a film structure, thickness, and surface morphology dependency on the mechanical properties for these metal oxide thin films.     

膜厚均匀性函数的分析

为了解决膜层层数在一百多层以上的膜系在镀制过程中所必然存在的膜厚均匀性问题,定义了一个与镀膜机的结构参数、工艺参数以及基片几何参数均有关系的均匀性函数。以APS1104镀膜机为实验对象,针对多腔窄带滤光片膜系,根据此函数分析了镀膜机镀制较多层数薄膜时,其膜层厚度沿基片径向的变化规律,确定了影响膜厚均匀性的多种因素,解释了镀制多腔窄带滤光片薄膜成品率低的原因。实验结果证实了分析的正确性。