在日新月異的時代發展中，提高電子產品靈敏度、多功能性與縮小產品尺寸的驅動下，「微小化」製程已是自上世紀末以來在科技發展中的一項重要研究領域。尤其在應用的材料方面上，已不可避免的從三維塊材推展至二維薄膜，甚至縮小至一維尺度的奈米元件。其中由於近二十年來資訊科技的爆炸性發展，磁性材料的物理性質研究及其奈米結構化製程具有空前的發展盛況。因此，本文以磁性多層膜之元件製程研究與應用為主軸，除了帶入磁阻元件的發展，並介紹磁性元件製程技術以及磁阻材料之應用。

In the advanced development of modern technology and driven by improving the sensitivity, versatility and reducing the size of electronic products, process of miniaturization has become one of the most important research since the late last century. From the viewpoint of materials science development, the trend has inevitably moved from three-dimensional bulk to two-dimensional thin film regime, and furthermore moved into one-dimensional nano-devices. Among the most attractive materials research the fundamental physics and nanostructured techniques of magnetic material has emerged at the forefront of global research community due to the rapid development of information science and technology in the last two decades or so. Herein, the advancement of magnetic multilayers is introduced, especially the fabrication process and applications of magnetoresistive devices are focused.