交换耦合双层膜NiO/Ni81Fe19的基片温度效应研究

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H_c（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（H_EX）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，H_EX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T_B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．

Effect of Substrate Temperature on NiO/Ni81Fe19 Exchange Coupling Double-layered Films

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