Mn-Fe-P-Si薄膜的制备与性能研究

Preparation and Magnetic Properties of Mn-Fe-P-Si Thin Film

摘要: 本文主要研究了金属磁热材料Mn-Fe-P-Si薄膜的制备工艺及其磁性能。利用脉冲激光沉积法分别在刚性Si衬底和柔性云母Mica衬底上沉积Mn-Fe-P-Si薄膜。结果表明，在刚性Si衬底上制备的薄膜呈现明显孔隙，连续性较差，这可能是由于Mn-Fe-P-Si与衬底晶格参数存在失配引起的。而在柔性Mica衬底上Mn-Fe-P-Si薄膜元素分布均匀且致密性好。此外，本文还研究Mn-Fe-P-Si薄膜的结晶性和磁性能与退火温度的相关性。结果显示在退火温度低于1000℃时，Mn-Fe-P-Si薄膜结晶度较低，相应的磁性能也较差。当退火温度达到1100℃后，Mn-Fe-P-Si薄膜充分结晶，且表现出良好的磁性能。本论文有关Mn-Fe-P-Si薄膜形态的研究将有利于提升磁热材料的机械性能，为其实用化提供理论基础。

Abstract: This paper mainly focuses on the preparation and the magnetic properties of the metallic magne-tocaloric material Mn-Fe-P-Si thin film. Pulsed laser deposition method was utilized to prepare Mn-Fe-P-Si thin film on stiff Si substrate and flexible Mica substrate, respectively. The experimental results show that the thin film deposited on stiff Si substrate displays remarkable pores and poor continuity, which could be ascribed to the mismatch of the lattice parameters between Mn-Fe-P-Si and Si substrate. While the thin film deposited on flexible Mica substrate is homogenous and dense. Furthermore, this paper studies the relation between the crystallinity of Mn-Fe- P-Si thin film and the annealing temperature. The results tell that the crystallinity of Mn-Fe-P-Si thin film is relatively poor for annealing temperature below 1000˚C, thus leading to low magnetization, while a good crystallinity and magnetization of Mn-Fe-P-Si thin film can be achieved when the annealing temper-ature excesses 1100˚C. The study of Mn-Fe-P-Si in the film state could promote the mechanical properties of magnetocaloric materials and provide theoretical support for future applications.