NiO/NiFe双层膜的制备及其交换耦合作用研究

FABRICATION AND EXCHANGE COUPLING OF NiO/NiFe BILAYERS

用直流磁控反应溅射制备ＮｉＯ／ＮｉＦｅ双层膜。在保持ＮｉＦｅ层的厚度２０ｎｍ不变的条件下，发现尽管没有用外加磁场引导单向各向异性，由于底盘旋转等因素的影响，ＮｉＯ（７０ｎｍ）／ＮｉＦｅ（２０ｎｍ）双层结构仍显示较好的单向各向异性，交换耦合场可达３０Ｏｅ以上。通过改变ＮｉＯ层的厚度、溅射气体Ａｒ分压以及溅射气体与反应气体的比例Ａｒ／Ｏ２，研究了反铁磁层厚度以及溅射条件对交换耦合场的影响。

The NiO/NiFe bilayers were fabricated with DC magnetron sputtering. Keeping the thickness of the NiFe layers constant at 20nm, it was found that the as deposited bilayers of NiO(70nm)/NiFe(20nm) showed fairly good unidirectional anisotropy. The exchange field could be as large as 30 Oe although there was no magnetic field to induce an unidirectional anisotropy. The changes of the exchange fields with the thickness of NiO layers, the partial pressure of Ar and the ratio of Ar/O 2 were observed. The mechanisms of these changes were discussed.