磁控溅射Al-Fe-Sn 薄膜的电输运性能

The electrical transportation behavior of magnetron sputtered Al-Fe-Sn thin film

摘要:

在电子工业中，为了制备低电阻率的Al合金薄膜，需要对薄膜进行退火。虽然材料的电阻率与其电输运性能密切相关，然而目前为止，对于铝合金薄膜的电输运性能研究甚少。 本文首先利用TEM对于磁控溅射铝合金薄膜的结构，特别是与基底界面处的结构进行了表征。在此基础上，利用霍尔效应测试了解界面状态的变化对于霍尔载流子浓度及迁移率的影响。 我们实验的结果表明， 在退火的过程中，薄膜与下层基底之间通过扩散过程形成紧密接触，从而使得合金薄膜同时具有较高的载流子浓度以及载流子迁移率。最后，利用一个新提出的能带模型，解释所观察到的界面变化对于电导率的影响。

Abstract:

During the manufacturing of Al-based thin films for electronic applications, a post-deposition annealing is required in order to achieve a lower resistivity. However, the electrical transportation behavior of the magnetron sputtering Al film has been rarely investigated. To address this objective, we have explored the microstructure of the film before and after annealing with emphasis on the structural features related to diffusion and interface using TEM observation. Hall-effect measurement was employed to determine the variation of carrier density and mobility brought by the evolution originating at the interface. The results demonstrate that during annealing an intimate contact was formed between the film and substrate via diffusion, leading to a combination of high mobility and high density. Furthermore, a model was proposed from the aspect of energy bands in order to explain the positive effect of the interface phenomenon upon electron conductivity.