微波高磁导率铁氧体-合金软磁多层膜材料结构设计与性能调控

The development of soft magnetic thin films with high initial permeability under the application of microwave devices, which use of the characteristics of ferrite thin films with high resistivity and alloy thin films with high initial permeability, has important application value and scientific significance. However, presently, NiZnCo ferrite thin films with low initial permeability and FeCo alloy thin films with low resistivity hindered the application for microwave devices. Combining first principle theory with magnetron sputtering fabrication, the project intends to investigate the implementation condition of NiZnCo ferrite-FeCo alloy multilayer thin films, establish the rules between performance and the key process parameters, and carry out the control of high frequency magnetic properties. The NiZnCo ferrite-FeCo alloy multilayer thin films with high initial permeability will be prepared by design and optimizing of the multilayer thin films structrue. At the same time, the associated physical mechanism of “structure-electromagnetic properties” and “preparation technology- electromagnetic properties” will be established according to the measured results of structural and electromagnetic properties, to explore the control rules in the preparing process of NiZnCo ferrite-FeCo alloy multilayer thin films.

利用软磁铁氧体具有高电阻率和软磁合金具有高起始磁导率的特点制备出应用于微波器件的高磁导率软磁薄膜具有重要应用价值和科学意义。而目前NiZnCo铁氧体薄膜的低起始磁导率和FeCo合金薄膜的低电阻率阻碍了两种薄膜材料在微波器件领域的应用。本项目拟通过基于量子力学理论的第一性原理模拟和磁控溅射制备相结合的方法，研究NiZnCo铁氧体-FeCo合金多层膜的实现条件，建立性能与关键工艺参数间的规律，实现NiZnCo铁氧体-FeCo合金软磁多层膜高频磁特性调控。项目拟以NiZnCo铁氧体和FeCo合金为靶材，通过对薄膜的结构进行优化设计来调控多层膜材料的电磁性能，制备出应用于微波器件的高磁导率NiZnCo铁氧体-FeCo合金软磁多层膜，同时根据结构与电磁性能表征结果，建立“结构-电磁性能”与“制备工艺-电磁性能”的物理关联模型，实现NiZnCo铁氧体-FeCo合金多层膜材料在制备过程中的性能调控。

利用软磁铁氧体具有高电阻率和软磁合金具有高起始磁导率的特点制备出应用于微波器件的高磁导率软磁薄膜具有重要应用价值和科学意义。而目前NiZnCo铁氧体薄膜的低起始磁导率和FeCo合金薄膜的低电阻率阻碍了两种薄膜材料在微波器件领域的应用。因此，为了突破Snoek 极限，本项目利用磁控溅射技术制备NiZnCo铁氧体-FeCo合金多层膜材料，实验上确定了NiZnCo薄膜射频磁控溅射制备工艺为：背底气压4×10-4Pa，溅射气体为高纯氩气，溅射气压1.5Pa，溅射功率140W，溅射时间90分钟，基片采用Si（100）与Si（111）。溅射过程中基片不加热。薄膜样品在空气中退火温度为800℃，保温时间为120分钟。实验上确定了FeCo合金薄膜射频磁控溅射制备工艺为：背底气压低于4.0×10-4Pa，溅射气体为高纯氩气，溅射气压1.0Pa，溅射功率120W，溅射时间60分钟，基片采用Si（100）。溅射过程中基片不加热。为微波磁性材料应用在现代无线电通信、蓝牙、手机、卫星电视、电磁波屏蔽以及计算机存储等领域与广泛应用于军事领域和人们的日常生活生产等方面的小型化、平面化、薄膜化、集成化的要求，提供了重要的实验支撑。