Magnetic properties and structure of very thin permalloy films

In order to study the magnetic properties and structure of very thin permalloy films, Ni81Fe19 films of 12 nm in thickness were prepared by different instruments at an ultrahigh base vacuum and a lower base vacuum. The anisotropic magnetoresistance coefficients (△R/R) of Ni81Fe19 (12 nm) films reached 1.6 % and 0.6 %, and the coercivities were 127 and 334 A/m, respectively. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were used to study the structure and surface chemical state. The experimental results show that the films prepared at the ultrahigh base vacuum have a smoother surface, a bigger grain size and a denser structure with fewer defects than those prepared at the lower base vacuum.     

金刚石薄膜的制备及透射率研究

用磁控溅射法制备金刚石薄膜,研究了工作气压、溅射电流、镀膜时间三个参数对金刚石薄膜透射率的影响。得到最佳工艺参数:工作气压1.3Pa,溅射电流0.4A,镀膜时间2min。镀制的金刚石薄膜可以作为红外元件的保护膜与增透膜。     

Photoluminescence properties of ZnO thin films prepared by DC magnetron sputtering

ZnO thin films were prepared by direct current（DC） reactive magnetron sputtering under different oxygen partial pressures And then the samples were annealed in vacuum at 450 ℃. The effects of the oxygen partial pressures and the treatment of annealing in vacuum on the photoluminescence and the concentration of six intrinsic defects in ZnO thin films such as oxygen vacancy（Vo）, zinc vacancy（VZn）, antisite oxygen（OZn）, antisite zinc（Zno）, interstitial oxygen（Oi） and interstitial zinc（Zni） were studied. The results show that a green photoluminescence peak at 520 nm can be observed in all the samples, whose intensity increases with increasing oxygen partial pressure; for the sample annealed in vacuum, the intensity of the green peak increases as well. The green photoluminescence peak observed in ZnO may be attributed to zinc vacancy, which probably originates from transitions between electrons in the conduction band and zinc vacancy levels, or from transitions between electrons in zinc vacancy levels and up valence band.     

Effect of Ag addition on the microstructure and magnetic properties of FePt thin films

FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin films, effects of Ag addition on the structure and properties of FePt thin films were investigated. Proper Ag addition was found helpful for FePt phase transition at lower annealing temperature. With Ag addition, the magnetic domain pattern of FePt thin film changed from maze-like pattern to more discrete island-like domain pattern in [FePt/Ag]n multilayer thin films. In addition, introducing nonmagnetic Ag hindered FePt grains from growing larger. The in-depth defects in FePt films and [FePt/Ag]n multilayer films verify that Ag addition is attributed to a large number of pinning site defects in [FePt/Ag]n film and therefore has effects on its magnetic properties and microstructure.     

射频溅射功率和掺杂氢对硅氢薄膜结构的影响

采用SEM和Raman谱对射频磁控溅射法制备的硅氢薄膜结构进行了研究,讨论了在100～400W范围内溅射功率和氢气分压对硅氢薄膜结构的影响。结果表明,制备的硅氢薄膜为致密的颗粒膜,添加氢气后,颗粒状的硅氢薄膜出现了粒径更为细小的纳米级小颗粒亚结构;随着氢气分压的增加,其直径先增加后减小,平均直径在氢气分压为50％时达到最大;随着溅射功率的增加,硅氢薄膜的颗粒平均直径增加,当溅射功率达到400W时,颗粒的平均直径为104nm。拉曼光谱分析结果显示硅氢薄膜为非晶态。     

沉积压力对磁控溅射Mg薄膜结构的影响

采用直流磁控溅射方法在氧化锆固体电解质表面制备了Mg金属薄膜,利用XRD和SEM研究了沉积压力（0.9～2.1 Pa）对薄膜形貌和结构的影响.结果表明：随着沉积压力的提高,薄膜结晶程度逐渐变差,晶粒尺寸减小,表面粗糙度增大;薄膜呈（002）择优生长的柱状晶结构,且随着沉积压力的提高薄膜厚度先增加后减小.     

FePt/Ag薄膜的结构和磁性

采用直流磁控溅射在SiO2〈0001〉基片上制备了FeAg和FePt/Ag薄膜,将其在不同温度下进行真空热处理,得到具有高矫顽力的L10-FePt颗粒膜。利用X射线衍射、振动样品磁强计、扫描探针显微镜对样品的结构、磁性、形貌进行了研究。结果表明:Ag元素的添加有效地降低了FePt薄膜的有序化温度,样品在300℃热处理时即发生有序化转变。随着热处理温度的升高,样品的有序化程度提高,矫顽力变大,样品表面粗糙度减小,形成了均匀的颗粒薄膜。     

表面覆盖氮化硼膜的金刚石膜的场发射特性

利用热丝化学气相沉积（HFCVD）方法在Si衬底上生长了4μm厚的金刚石膜,然后利用射频磁控溅射方法在金刚石膜上沉积了100nm厚的六角氮化硼（h—BN）薄膜．在超高真空系统中测试了覆盖氮化硼（BN）薄膜前后金刚石膜的场发射特性,结果表明覆盖BN薄膜后的金刚石膜的场发射特性明显提高,开启电场由14V／μm升到8V／μm．F—N曲线表明,覆盖BN薄膜后的金刚石膜在强电场区域的场增强因子有所降低,这可能归因于场发射点随着电场的增强而改变．     

沉积参数对二氧化钛薄膜结构相变的影响

用磁控溅射的方法在硅衬底上制备了二氧化钛薄膜,并通过改变薄膜沉积过程中氧气含量、溅射时间、工作压强、衬底温度等溅射参数,制备了系列薄膜样品,得到了二氧化钛薄膜两种相结构的最佳生成条件.研究表明:较高的工作压强有利于金红石结构的生成;衬底加热、增加沉积时间有利于生成锐钛矿结构;氧气含量的变化对薄膜的相结构没有明显影响.     

Microstructure and magnetic properties of granularFePt/(FePt)_(27)Ti_(73) films for ultrahigh-density recording media

1　INTRODUCTIONThe increasing demand for the areal density inmagnetic recording has driven the recording bit tosmaller dimensions, and it is necessary to decreasegrain size to 8 nm to achieve the areal density of155 Gb/cm2. However, with such small grainsize, the grain magnetization becomes thermallyunstable because of superparamagnetic limitation.In order to overcome the thermal instability, highanisotropy is most necessary because high magne tocrystalline anisotropy …     

制备参数对TbFeCo磁光薄膜性能的影响

对采用磁控溅射制备TbFeCo/Si、Ag/TbFeCo/Si系列薄膜的溅射工艺进行了研究,分析了TbFeCo薄膜的生长机理,并对其光学性质、磁性质和磁光性质进行了分析。实验结果表明,不同压强对TbFeCo薄膜的成分比有明显的影响,确定了工作压强为2.0 Pa是适合的,这时制备的薄膜的成分原子比和靶的原子比最接近。用全自动椭圆偏振光谱仪测量了TbFeCo薄膜在1.5~4.5eV的椭偏光谱,结果表明,随着工作气压、溅射功率和Ar气流量的变化,薄膜的光学性质均发生明显变化。对制备的Ag/TbFeCo/Si和TbFeCo/Si磁光薄膜的磁光性质进行了分析,结果表明,Ag保护膜对TbFeCo磁光薄膜的磁光性质会产生显著影响。     

Cu（Al）／SiO2复合薄膜及显微特征

采用真空离子镀膜机在SiO2玻璃基片表面分别蒸镀Cu和Al薄膜,3组参数6次制备12个铝或铜薄膜试样．实验表明：相同工艺条件下,铝膜较铜膜附着力更强,膜厚更大,更易形成薄膜且结构均匀致密．经测试可知：当铝膜的轰击电压为175V,烘烤电压为160V,蒸镀时间为2h、铜膜的轰击电压为200V,烘烤电压为100V,蒸镀时间为1．8h,制得的样品纯度高,杂质含量少,微观结构与膜厚最理想,界面结构规范,平滑,吸附力强,薄膜界面微观粗糙性和形状较佳．     

Al掺杂对ZnO薄膜结构和光学性能的影响

研究了Al掺杂对采用直流磁控溅射方法制备的ZnO薄膜结构及光学性能的影响。X射线衍射结果揭示薄膜具有良好的C轴择优取向生长特性,同时,衬底温度对它们的透射谱和荧光谱有着明显影响,所有薄膜都有大于86%的可见光透过率和陡峭的本征吸收边,但ZAO薄膜的光学透过率略低。Al掺杂导致了更宽的光学带隙,光致发光光谱显示ZnO具有较强的近带本征吸收峰和深能级发射峰,但Al掺杂使得深能级发射峰降低。随着衬底温度的升高,近带边吸收峰蓝移,与光学带隙Eg变化趋势一致。     

The effect of working gas pressure and deposition power on the properties of molybdenum films deposited by DC magnetron sputtering

Molybdenum films were deposited on Corning 7059 glass substrates by DC magnetron sputtering with different working gas pressures and sputtering powers.The structure and morphology,residual stress and adhesion,resistivity and optical reflectance of the as-deposited Mo films were investigated.The results show that Mo films deposited with high working gas pressure and low sputtering power have a spherical surface morphology,small grain size,residual compressive stress and a good adhesion,high resistivity and low optical reflectance.With the working gas pressure decreased and the sputtering power increased,Mo films have elongated spindle-shape or diamond flake shape surface morphology,the grain size is increased,with residual stress changed from tensile to compressive,a poor adhesion,resistivity decreased and optical reflectance increased.     

氧气分压对磁控溅射法制备ZAO膜的影响

利用直流磁控溅射技术在无机玻璃衬底上制备了ZAO透明导电薄膜。研究了溅射过程中氧气分压对ZAO薄膜的结构和光电特性的影响，结果表明：当氧气分压为0Pa时，薄膜结晶度良好，具有最小电阻率和较高的可见光透过率。     

磁控溅射法制备镍热敏薄膜的工艺研究

为了提高用作红外探测器敏感材料的镍膜的性能,采用直流磁控溅射的方法在载玻片上制备测辐射热计的热敏感薄膜一镍膜,靶材选用高纯镍（99．99％）．采用四探针电阻特性测试仪测试了所制备的镍热敏薄膜在不同温度下的方块电阻,根据测试曲线计算薄膜的电阻温度系数（TemperatureCoefficientofResistance,TCR）．研究了工作气压、氩气流量以及溅射功率对镍膜TCR的影响．实验研究表明,当溅射功率为225W,工作气压为1Pa,氩气流量为120sccm,溅射时间为3min时,制备出的镍膜方阻为2．9Ω／口,TCR为2．3×10^-3／K．     

Structural and physical properties of permalloy thin films prepared by DC magnetron sputtering at different substrate temperature

Permalloy Ni80Fe20 films have been grown on thermal oxidized Si (111) wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 K in 0.65 Pa argon pressure. The base pressure was about 1×10-4 Pa. The deposition rate was about 5 nm/min for all the films. The structure of the films was studied using X-ray diffraction, scanning electron microscopy and atomic force microscopy. The composition of the films was analyzed using scanning Auger microprobe. The resistance and magnetoresistance of the films were measured using four-point probe technique. The results show that the content of oxygen in the films decreases gradually with raising substrate temperature. In addition, the surface morphology of the films presents notable change with the increasing of the substrate temperature; the residual gases and defects decrease and the grains have coalesced evidently, and then the grains have grown up obviously and the texture of (111) orientation develops gradually in the grow     

Surface and electrical properties of NiCr thin films prepared by DC magnetron sputtering

Several batches of NiCr alloy thin films with different thickness were prepared in a multi-targets magnetron sputtering apparatus by changing sputtering time while keeping sputtering target power of Ni and Cr fixed. Then the as-deposited films were characterized by energy-dispersive X-Ray spectrometer （EDX）, Atomic Force Microscope （AFM） and four-point probe （FPP） to measure surface grain size, roughness and sheet resistance. The film thickness was measured by Alpha-Step IQ Profilers. The thickness dependence of surface roughness, lateral grain size and resistivity was also studied. The experimental results show that the grain size increases with film thickness and the surface roughness reaches the order of nanometer at all film thickness. The as-deposited film resistivity decreases with film thickness.     

高频电磁屏蔽用ITO膜结构与性能分析

采用阴极磁控溅射法制备用于电磁屏蔽的ITO透明导电膜,方块电阻在5～40Ω／□范围内。测试不同方块电阻膜层的电阻率、膜厚、可见光透光度、雾度、对8～18GHZ频率范围内电磁波的反射率等性能,通过X射线衍射图谱和X射线回摆曲线研究膜层的结晶程度和晶粒大小对膜层性能的影响,引入特性优化因子来综合评价膜层的性能。     

Sputtering preparation and magneto-optical properties of GdTbFeCo thin films

Amorphous GdTbFeCo magnetic thin films were successfully prepared on glass substrates by RF magnetron sputtering system from a mosaic target.The influences of sputtering parameters on the magneto-optical properties GdTbFeCo thin film were investigated by the variable control method.And the influence mechanism was analyzed in detail.After the sputtering parameters were optimized,it was found that when the distance between target and substrate was 72 mm,the thin film thickness was 120 nm,and the sputtering power,sputtering pressure and sputtering time was 75 W,0.5 Pa and 613 s,respectively,the coercivity with perpendicular anisotropy could be as high as 6735 Oe,and the squareness ratio of the hysteresis loop was almost equal to 1.