尖晶石型钴铁氧体(CoFe2O4)因具有良好的电磁性质，广泛应用于计算机技术、航空航天及医学生物等领域。特别是钴铁氧体薄膜在磁电复合材料中具有良好的应用前景。本文基于密度泛函理论的第一性原理平面波赝势法，结合广义梯度近似，通过采用更接近于实验上外延生长的二维应变模型，研究了钴铁氧体薄膜的结构稳定性、电子结构和磁性能。结果表明：在二维应变作用下，反尖晶石结构的钴铁氧体比正尖晶石结构的稳定，但是与平衡基态相比，两者能量差减小，这表明在应变作用下，八面体晶格中的Co2+离子与四面体晶格中的Fe3+离子更容易进行位置交换，形成混合型结构的钴铁氧体；同时随着应变的增大，钴铁氧体的能带带隙减小，晶格中的原子磁矩发生变化，但总磁矩变化不明显。

Spinel ferrites, such as CoFe2O4, can be used in various fields such as computer technology, aerospace, and medical biotechnology due to their good electromagnetic properties. Although, CoFe2O4 thin films have good application prospects in the magnetoelectric composites, the effects of strain on the electronic structure and magnetic properties of cobalt ferrite film have not been reported. Through the use of two-dimensional strain model closer to the epitaxial growth experiments, the films of Cobalt ferrite are simulated on various substrates with a realistic biaxial strain model by first-principles plane-wave pseudopotential method based on density functional theory, and combined with the generalized gradient approximation in the paper. And the structural stabilities, electronic structures and magnetic properties of CoFe2O4 films are studied. The results show that the inverse spinel is still energetically favored under strain, but the energy difference decreases, thus Fe3+ions in the

采用反应直流磁控溅射法在镍锌铁氧体基片上制备 Cu掺杂的 TaN薄膜。通过调节氮流量，研究了不同氮流量下Cu掺杂对TaN薄膜电性能的影响。由XRD结果可见，TaN薄膜中掺杂Cu可在2θ＝54°出现Cu3 N相，在2θ＝57°出现CuN6相。氮流量的增加造成的结果：Cu掺杂的TaN薄膜厚度逐渐减小，薄膜的方阻和电阻温度系数（TCR）绝对值均增加。与无Cu掺杂的TaN薄膜的方阻和 TCR作了比较，发现 TaN薄膜掺杂 Cu可有效改善薄膜的方阻和TCR。

TaN thin films with copper doping were prepared on Ni-Zn ferrite substrate by the reactive DC mag-netron sputtering method.With different nitrogen content,the influences of Cu doping on the electrical properties of the samples were investigated by adj usting nitrogen content.The X-ray diffraction (XRD)results show that Cu3 N and CuN6 phases appear at 2θof 54°and 57°in copper doping TaN thin films,respectively.The results caused by nitrogen content increase are that the square resistance and the absolute value of temperature coefficient of resistance (TCR)increase with the thickness decrease.Compared with the square resistance and the TCR of the TaN thin films without Cu doping,the square resistance and the TCR of Cu doping TaN thin films were improved effectively.

研究了基于高饱和磁感应强度的铁硅铝软磁材料的复合软磁材料薄膜的低温成型工艺和磁性能。绝缘包覆工艺上,使用高电阻率的锰锌铁氧体软磁粉末做绝缘剂。粘结工艺上,使用水玻璃做粘结剂,低温固化粘结。与传统工艺比,低温成型工艺与微加工工艺兼容。应用该工艺制作了软磁薄膜,采用超景深三维显微系统VHX-2000观测复合材料的微观结构;运用振动样品磁强计测试薄膜的静态磁性能参数;使用交流磁化率测量仪测试薄膜动态磁性能参数。针对软磁磁粉颗粒度、绝缘包覆、粘结成型等不同工艺因素,制作了薄膜样品,总结了不同工艺因素对薄膜综合磁性能的影响。

This paper introduces the general magnetic properties and a new low temperature modeling process of a special compound soft magnetic film based on FeSiAl powder.In this experiment,the ZnMn ferrite soft mag-netic powder with high resistivity was insulator.Waterglass was used as binder for low temperature modeling. Compared with conventional process,low temperature modeling process was compatible with micro-nano fabri-cation.In the end,we use microscope system VHX-2000 to observe the micro structure of the compound mate-rial.The static magnetic parameters will be tested by using the module of PPMS (physical property measure-ment system)called VSM (vibrating sample magnetometer).The dynamic magnetic parameters will be tested by the ACMS (alternating current magnetization susceptibility)instrument.In the end,we make the final prac-tical sample with different technical elements.These elements include particle size of the powder,the content of insulator as well as the content of the binder.A

针对13.56MHz RFID系统大面积平面螺旋线圈天线存在的缺陷，提出了一种用于13.56MHz频段的新型RF-MEMS微天线，并使用HFSS软件进行了仿真和设计，同时采用MEMS工艺实现器件制作。该微天线由螺线管线圈及高性能铁氧体薄膜组成，总体尺寸小于10mmx6.7mmx0.46mm。该微天线灵敏度达到了36.2mV/μT，使用电感值为1.6μH的读卡器线圈与匹配谐振后的微天线进行耦合，在6mm处该微天线的谐振电压达到7.1V，同时将集成了标签芯片及谐振电容的微天线与符合 ISO14443标准的读卡器进行通信，其通信距离达到12mm。

In this paper, a novel RF-MEMS antenna for 13.56MHz applications is presented to resolve the problems exist in the large area spiral antenna. RF-MEMS antenna is simulated and designed by means of high frequency structure simulator (HFSS) software. By MEMS process, the micro antenna has been fabricated, which consists of solenoid-type coil and high performance ferrite film, and has a measurement of less than 10mm×6.7mm×0.46mm. Test results show that the sensitivity of the micro antenna achieves 36.2mV/μT. Voltages up to 7.1 V were obtained at the resonant micro antenna from a 1.6μH reader coil at 6 mm distance. The assembled micro antenna with RFID chip and capacitor was tested using an ISO14443 type RFID reader at 13.56 MHz and successful communication was established at a distance of 12 mm.