Cobalt thin films were deposited on silicon substrates by magnetron sputtering two commercial cobalt targets with different pass-through fluxes (PTFs). The influences of PTF on the magnetic properties of sputtered thin films were investigated. The results indicate that under the same sputtering conditions, cobalt thin film deposited by Co target with high PTF (84.21%) has lower remanence ratio (0.65), while cobalt thin film prepared by Co target with low PTF (69.13%) has higher remanence ratio (0.87). Through introducing an external magnetic field parallel to the film surface during sputtering processes, both the remanence ratios of cobalt thin films prepared by the two targets can be enhanced to approach 1. High-resolution transmission electron microscopy (HRTEM) images show that in the absence of the external magnetic field during sputtering, cobalt thin film deposited by the target with high PTF is randomly oriented in crystallographic orientations, which is due to that Co atoms have no enough time to migrate and diffuse on substrate and the atomic stacking is disordered. It is worth mentioning that crystallographic orientations of cobalt thin film deposited by target with low PTF are relatively consistent, resulting in relatively higher remanence ratio. In addition, HRTEM analysis indicates that the external magnetic field during sputtering drives the Co grains to arrange in a regular order with (002) orientation, leading to the improvement in remanence ratios.

中文翻译：

---

钴靶穿通通量与溅射薄膜微观结构和磁性能的相关性

通过磁控溅射两个具有不同通透通量 (PTF) 的商用钴靶，在硅衬底上沉积钴薄膜。研究了PTF对溅射薄膜磁性能的影响。结果表明，在相同溅射条件下，高PTF（84.21%）Co靶材沉积的钴薄膜剩磁率较低（0.65），而低PTF（69.13%）Co靶材制备的钴薄膜剩磁较高比率 (0.87)。通过在溅射过程中引入平行于薄膜表面的外部磁场，两个靶材制备的钴薄膜的剩磁比都可以提高到接近 1。高分辨率透射电子显微镜 (HRTEM) 图像显示，在没有溅射过程中的外部磁场，高PTF靶沉积的钴薄膜在晶体取向上随机取向，这是由于Co原子没有足够的时间在衬底上迁移和扩散，原子堆积无序。值得一提的是，低PTF靶材沉积的钴薄膜晶体取向相对一致，导致剩磁率相对较高。此外，HRTEM 分析表明，溅射过程中的外部磁场驱动 Co 晶粒以（002）取向的规则排列，导致剩磁比提高。这是因为 Co 原子没有足够的时间在衬底上迁移和扩散，原子堆积是无序的。值得一提的是，低PTF靶材沉积的钴薄膜晶体取向相对一致，导致剩磁率相对较高。此外，HRTEM 分析表明，溅射过程中的外部磁场驱动 Co 晶粒以（002）取向的规则排列，导致剩磁比提高。这是因为 Co 原子没有足够的时间在衬底上迁移和扩散，原子堆积是无序的。值得一提的是，低PTF靶材沉积的钴薄膜晶体取向相对一致，导致剩磁率相对较高。此外，HRTEM 分析表明，溅射过程中的外部磁场驱动 Co 晶粒以（002）取向的规则排列，导致剩磁比提高。