交换耦合双层膜NiO/Ni_(81)Fe_(19)的基片温度效应研究

Effect of Substrate Temperature on NiO/Ni_(81)Fe_(19) Exchange Coupling Double-layered Films

用射频磁控溅射方法在不同基片温度下玻璃基片上分别制备NiO单层膜、NiFe单层膜和NiO／NiFe双层膜，研究了不同基片温度对膜的磁性能的影响．用振动样品磁强计（VSM）分析了膜的磁特性，结果表明：基片温度260℃时淀积的NiFe膜矫顽力Hc为184A·m－1，小于室温淀积NiFe膜的Hc（584A·m－1），且磁滞回线的矩形度更好．室温下淀积NiO（50nm）／NiFe（15nm）双层膜的Hc为4000A·m－1，交换耦会场（HEX）仅为1600A·m－1，磁滞回线的短形度很差，而260℃时淀积的双层膜的Hc下降到3120A·m－1，HEX却增大为4640A·m－1，同时磁滞回线的矩形度也得到改善，其截止温度TB高达230℃．X射线衍射（XRD）分析了膜的织构，结果表明：室温下淀积NiO膜呈现（220）织构，而260℃时淀积NiO膜呈现（111）织构；室温和260℃淀积的NiFe膜都呈（111）织构，但后者晶粒比前者大．

NiO films, NiFe films and double- layered NiO/NiFe films were prepared on glass substrates by rf magnetron sputtering. The temperature of substrates (TS) were varied from room temperature (TR) to 300℃. The HC of NiFe films deposited at TR was 584A·m-1, it became 184A·m-1 while the Ts increased to 260℃ and the squareness of hysteresis loop became better.The HC and HEX of NiO (50 nm)/ NiFe (15 nm) deposited at TR were 4000A·m-1 and 1600A·m-1,respectively. The HC decreased to 3120A·m-1 and HEX increased to 4640A·m-1 while the TS was 260℃. The squareness of hysteresis loop also became better and the blocking temperature (TB)was 230℃. XRD analysis indicated that the NiO films deposited at TR presented (220) texture whereas the films deposited at 260℃ showed (111) texture. The NiFe films deposited at TR and 260℃ both presented (111) texture, but the crystal particle size of the latter waJs larger.