Ti/Ti-类金刚石多层膜的制备与表征

采用电子回旋共振-化学气相沉积结合中频磁控溅射的真空镀膜技术, 以99.99%Ti为靶材, 乙炔为碳源制备了Ti/Ti-类金刚石(DLC)多层膜. 利用X射线衍射仪、扫描电子显微镜、X射线光电子能谱仪 对Ti/Ti-DLC多层膜进行了相结构、组织、成分及形态分析. 采用显微硬度仪、摩擦磨损仪、表面粗糙度仪对Ti/Ti-DLC多层膜进行了力学性能考察. 结果表明: Ti/Ti-DLC多层膜中主要含有TiC晶相; Ti层和Ti-DLC层中未出现柱状晶体生长模式, 分层中均以岛状模式生长; 当调制周期Λ≤ 50 nm时, 分层结构变模糊; 调制周期Λ对Ti/Ti-DLC多层膜的复合硬度、摩擦系数、表面形貌、表面粗糙度都有影响, 当调制周期Λ较小时表现出纳米增硬效应, 表面出现大颗粒, 表面粗糙度和摩擦系数均变大.     

中心波长为13．9nm的正入射Mo／Si多层膜

用由铜靶激光等离子体光源等组成的反射率计对自行设计的周期厚度为7.14nm的120层Mo/Si多层膜进行极紫外(EUV)波段反射率测量。由于多层膜层数增加所引起的吸收、膜层界面之间的扩散以及镀膜过程中的膜厚控制误差或表面被氧化(污染)等原因,正入射Mo/Si多层膜在13.9nm处的反射率低于理论计算值73.2%,最后用原子力显微镜(AFM)测量其表面粗糙度为σ=0.401nm。     

Mo/Si软X射线多层膜的界面粗糙度研究

 用磁控溅射法分别制备了以Mo膜层和Si膜层为顶层的Mo/Si多层膜系列, 利用小角X射线衍射确定了各多层膜的周期厚度。以不同周期数的Mo/Si多层膜的新鲜表面近似等同于同一多层膜的内界面，通过原子力显微镜研究了多层膜界面粗糙度随膜层数的变化规律。并在国家同步辐射实验室测量了各多层膜的软X射线反射率。研究表明：随着膜层数的增加，Mo膜层和Si膜层的界面粗糙度先减小后增加然后再减小，多层膜的峰值反射率先增加后减小。     

23.4nm软X射线多层膜反射镜研制

为了满足类氖-锗X射线激光研究的需要,设计制备了23.4 nm软X射线多层膜反射镜.依据多层膜选材原则并考虑材料的物理化学特性选择新的材料Ti与Si组成材料对.设计优化材料多层膜的周期厚度(d),材料比例(Γ),周期数(N),计算出Ti/Si反射率曲线.通过实验优化各种镀膜工艺参数,制备出了23.4 nm的Ti/Si多...     

Co/Ti金属磁性多层膜的激光布里渊散射研究(英文)

在室温下利用直流磁控溅射法制备出了具有不同Co层厚度的 [Co(dConm) /Ti(dTinm) ]n 金属磁性多层膜 (其中dCoanddTi是Co和Ti的厚度 ,n薄膜调制周期数 )。在 30 0K下用X射线衍射法 (XRD)和布里渊散射方法研究了Co层厚度分别为dCo=1 ,2 ,2 5 ,3 5nm ,Ti层厚度为dTi=2 5nm的Co/Ti多层膜。XRD的结果所示在Co/Ti多层膜中Co层厚度超过 2 5nm ,其结构类似块材Co的多晶结构。对比之下 ,Co/Ti多层膜中Co层厚度低于 2 5nm ,其XRD衍射峰随Co层厚度减少变的峰形加宽 ,衍射峰的强度减少 ,峰位移动和消失。在Co/Ti多层膜中自旋波的布里渊散射结果表明 :在Co/Ti多层膜中 ,对于dCo>2 5nm磁性呈铁磁性耦合 ,在dCo≤ 2 5nm时 ,其呈反铁磁性耦合。除表面自旋波外 ,在呈反铁磁性耦合的材料中观测到了两个有体特征的自旋波 ,而在呈铁磁耦合的材料中只观测到一个有体特征的自旋波。     

用不同的Mo靶溅射功率制备Mo/Si多层膜

 用磁控溅射法制备了周期厚度和周期数均相同的Mo/Si多层膜，用原子力显微镜和小角X射线衍射分别研究了Mo靶溅射功率不相同时，Mo/Si多层膜表面形貌和晶相的变化。随后在国家同步辐射实验室测量了Mo/Si多层膜的软X射线反射率。研究发现，随着Mo靶溅射功率的增大，Mo/Si多层膜的表面粗糙度增加，Mo的特征X射线衍射峰也增强，Mo/Si多层膜的软X射线峰值反射率先增大后减小。     

4.48 nm正入射软X射线激光用Cr/C多层膜高反射镜的研制

针对4.48nm类镍钽软X射线激光及其应用实验,设计制备了工作于这一波长的近正入射多层膜高反射镜。选择Cr/C为制备4.48nm高反射多层膜的材料对,通过优化设计,确定了多层膜的周期、周期数以及两种材料的厚度比。模拟了多层膜非理想界面对高反射多层膜性能的影响。采用直流磁控溅射方法在超光滑硅基片上实现了200周期Cr/C多层膜高反射镜的制备。利用X射线衍射仪测量了多层膜结构,在德国BessyⅡ同步辐射上测量了在工作波长处多层膜反射率,测量的峰值反射率达7.5%。对衍射仪测量的掠入射反射曲线和同步辐射测量的反射率曲线分别进行拟合,得到的粗糙度和厚度比的结果相近。测试结果表明,所制备的Cr/C多层膜样品结构良好,在指定工作波长处有较高的反射峰,达到了设计要求。     

高反射率Mo/B4C多层膜设计及制备

 运用遗传算法优化设计了Mo/B₄C多层膜结构。入射光入射角度取10°时,设计的理想多层膜膜对数为150,周期为3.59 nm,Gamma值（Mo膜厚与周期的比值）为0.41,峰值反射率为33.29%。采用恒功率模式直流磁控溅射方法制作Mo/B₄C多层膜。通过在Mo/B4C多层膜与基底之间增加15 nm厚的Cr粘附层,提高多层膜与基底的粘附力。另外,还采用调整多层膜Gamma值的方法减小其内应力,调整后多层膜结构周期为3.59 nm, Mo膜厚1.97 nm, B4C膜厚1.62 nm,峰值反射率26.34％。制备了膜对数为150的Mo/B₄C膜并测量了其反射率,在波长7.03 nm处,Mo/B₄C多层膜的近正入射反射率为21.0％。最后对测量结果进行了拟合,拟合得到Mo/B₄C多层膜的周期为3.60 nm,Gamma值0.60,界面粗糙度为0.30 nm。     

软X射线Mo/B_4C多层膜应力和热稳定性研究

为了实现7nm波段Mo/B4C多层膜反射镜元件的制备,研究了不同退火方式对Mo/B4C多层膜应力和热稳定性的影响。首先,采用直流磁控溅射方法分别基于石英和硅基板制作Mo/B4C多层膜样品,设计周期为3.58nm、周期数为60,Mo膜层厚度与周期的比值为0.4。其次,采用不同的退火方式对所制作的样品进行退火实验,最高退火温度500℃。最后,分别采用X射线掠入射反射、X射线散射和光学干涉仪的方法对退火前后的Mo/B4C多层膜的周期、界面粗糙度和应力进行测试。测试结果表明采用真空退火方式能够有效降低Mo/B4C多层膜的应力,且退火前后Mo/B4C多层膜的周期和界面粗糙度无明显变化,证明Mo/B4C多层膜在500℃以内具有很好的热稳定性。     

电子束蒸发氧化锆薄膜的粗糙度和光散射特性

利用电子束蒸发工艺，以Ag层为衬底，沉积了中心波长为632.8nm的氧化锆(ZrO₂)薄膜，膜层厚度在80—480nm范围内变化.研究了不同厚度样品的粗糙度变化规律和表面散射特性.结果发现，随着膜层厚度的逐渐增加，其表面均方根(RMS)粗糙度和总积分散射(TIS)均呈现出先减小后增大的趋势.利用非相关表面粗糙度的散射模型对样品的TIS特性进行了理论计算，所得结果与测量结果相一致. 关键词： 氧化锆 表面粗糙度 标量散射 电子束蒸发     

Characterization of the surface topography and nano-hardness of Cu/Ni multilayer structures

This article describes the results of a study of Cu/Ni multilayer coatings applied on a monocrystalline Si(100) silicon substrate by the deposition magnetron sputtering technique. Composed of 100 bilayers each, the multilayers were differentiated by the Ni sublayer thickness (1.2 to 3 nm), while maintaining the constant Cu sublayer thickness (2 nm). The multilayer coatings were characterized by assessing their surface topography using atomic force microscopy and their mechanical properties with nano-hardness measurements by the Berkovich method. The tests showed that the hardness of multilayers was substantially influenced by the thickness ratio of Cu and Ni sublayers and by surface roughness. The highest hardness and, at the same time, the lowest roughness was exhibited by a multilayer structure with a Cu-to-Ni sublayer thickness ratio of 2:1.5.     

Interface roughness, surface roughness and soft X-ray reflectivity of Mo/Si multilayers with different layer number

A series of Mo/Si multilayers with the same periodic length and different periodic number were prepared by magnetron sputtering, whose top layers were respectively Mo layer and Si layer. Periodic length and interface roughness of Mo/Si multilayers were determined by small angle X-ray diffraction (SAXRD).Surface roughness change curve of Mo/Si multilayer with increasing layer number was studied by atomic force microscope (AFM). Soft X-ray reflectivity of Mo/Si multilayers was measured in National Synchrotron Radiation Laboratory (NSRL). Theoretical and experimental results show that the soft X-ray reflectivity of Mo/Si multilayer is mainly determined by periodic number and interface roughness, surface roughness has little effect on reflectivity.     

Thermal behaviour of Co/Si/W/Si multilayers under rapid thermal annealing

The e-beam deposited multilayers (MLS) were studied under rapid thermal annealing (RTA) between 250°C and 1000°C during 30 s. MLS with five Co/Si/W/Si periods, each 13.9 nm (MLS1) and 18 nm (MLS2) were deposited onto oxidized Si substrates. Samples were analyzed by X-ray diffraction, hard and soft X-ray reflectivity measurements and grazing incidence X-ray diffuse scattering. The MLS period, interface roughness and its lateral and vertical correlations were obtained by simulation of the hard X-ray reflectivity and diffuse scattering spectra. The MLS1 with thinner Co layers is more temperature resistant. However, its soft X-ray reflectivity is smaller. The results show that this is because of shorter lateral and vertical correlation lengths of the interface roughness which may considerably influence the X-ray reflectivity of multilayers.     

Structure evolution and mechanical properties enhancement of Al/AlN multilayer

A set of Al/AlN multilayers with various modulation periods were prepared using DC magnetron sputtering method. Low angle X-ray diffraction (LAXRD) was used to analyze the layered structure of multilayers. The phase structure of the films was investigated with grazing angle X-ray diffraction (GAXRD). LAXRD results indicate that well-defined multilayer modulation structures are formed for the relatively larger modulation periods. However, the loss of mutilayered structure is detected in the multilayer with low modulation period. A very wide amorphous peak is observed in multilayer with modulation period of 4 nm. The multilayers show obvious crystallization at larger modulation periods, however, the diffraction peaks are much wider than the Al single layer because of the interruption of the continuous columnar grain growth by alternating deposition processes. Nanoindentation experiments were performed to study the mechanical properties as a function of multilayer modulation period. It is found that the hardness of the multilayers is greater than the hardness calculated from rule of mixtures. With the modulation periods adjusted, the multilayers are even harder than its hard component (AlN). A maximum hardness of 24.9 GPa, about 1.9 times larger than its hard component (AlN) and 3.7 times larger than the hardness calculated from the rule of mixtures, is found at the multilayer with modulation period of 16 nm. The wear test results show that the multilayers possess lower and stable friction coefficient, and superior wear properties.     

Ni thin films vacuum-evaporated on polyethylene naphthalate substrates with and without the application of magnetic field

We study the structural properties of the surface roughness, the surface mound size and the interfacial structure in Ni thin films vacuum-deposited on polyethylene naphthalate (PEN) organic substrates with and without the application of magnetic field and discuss its feasibility of fabricating quantum cross (QC) devices. For Ni/PEN evaporated without the magnetic field, the surface roughness decreases from 1.3 nm to 0.69 nm and the surface mound size increases from 32 nm to 80 nm with the thickness increased to 41 nm. In contrast, for Ni/PEN evaporated in the magnetic field of 360 Oe, the surface roughness tends to slightly decrease from 1.3 nm to 1.1 nm and the surface mound size shows the almost constant value of 28-30 nm with the thickness increased to 35 nm. It can be also confirmed for each sample that there is no diffusion of Ni into the PEN layer, resulting in clear Ni/PEN interface and smooth Ni surface. Therefore, these experimental results indicate that Ni/PEN films can be expected as metal/insulator hybrid materials in QC devices, leading to novel high-density memory devices.     

二氧化锆薄膜表面粗糙度的研究

采用电子束蒸发工艺,利用泰勒霍普森相关相干表面轮廓粗糙度仪,研究了不同基底粗糙度、不同二氧化锆薄膜厚度以及不同的离子束辅助能量下所沉积的二氧化锆薄膜的表面粗糙度。结果表明：随着基底表面粗糙度的增加,二氧化锆薄膜表面粗糙度呈现出先缓慢增加,当基底的粗糙度大于10nm后呈现快速增加的趋势;随着二氧化锆薄膜厚度的增加,其表面均方根粗糙度（RMS）先减小后增大;随着辅助沉积离子能量的增加,其表面粗糙度呈现出先减小后增加的趋势。     

Influence of interface roughness on reflectivity of tungsten/boron-carbide multilayers with variable bi-layer number by X-ray reflection and diffuse scattering

Infuence of interface roughness on the reflectivity of Tungsten/boron-carbide （W/B4C） multilayers varying with bi-layer number, N, is investigated. For W/B4C multilayers with the same design period thickness of 2.5 nm, a real-structure model is used to calculate the variation of reflectivities with N = 50, 100, 150, and 200, respectively. Then, these multilayers are fabricated by a direct current （DC） magnetron sputtering system. Their reflectivity and scattering intensity are measured by an X-ray diffractometer （XRD） working at Cu Kα line. The X-ray reflectivity measurement indicates that the reflectivity is a function of its bi-layer number. The X-ray scattering measured results show that the interface roughness of W/B4C multilayers increases slightly from layer to layer during multilayer growing. The variation of the reflectivity and interface roughness with bi-layer number is accurately explained by the presented realstructure model.     

多层膜［Co85Cr15/Pt］20的磁性、垂直磁记录特性和微结构的关系

采用磁控溅射法制备了性能优良的以Pt为缓冲层的［Co85₈₅Cr15_{15/Pt］2020 多层膜，研究了溅射气压对［Co8585Cr1515/Pt］2020多层膜微结构和磁性的 影响.研究结果表明，Ar溅射气压对［Co8585Cr1515/Pt］2020多层膜的微结构 、垂直磁各向异性和矫顽力有重要的影响 关键词： 溅射气压 多层膜 垂直磁各向异性 有效磁各向异性常数}