过渡金属氧化物有丰富的功能特性，同时有多种手段可以对其物理性能进行调控，其中对元素价态的调控可以实现对材料的电学、磁学性能的调控，吸引了许多研究者的关注。钴酸锶体系的物性丰富，而且随氧含量的改变，其性质也会发生明显的变化，如Sr2Co2O5是具有钙铁石结构的反铁磁绝缘体，而SrCoO3是具有钙钛矿结构的铁磁性金属。本文研究了Sr2Co2O5在脉冲激光沉 积系统中的最佳生长条件，通过非原位臭氧退火的方式将其氧化成了SrCoO3。为了研究其晶体结构和对称性，还测量了薄膜的 X 射线衍射图和拉曼散射光谱，Sr2Co2O5的拉曼散射光谱与空间群为 Imma（74）时的理论计算结果相吻合，实验结果验证了其晶体结构和对称性。通过比较在不同衬底上生长的Sr2Co2O5样品的 X 射线衍射图，发现样品晶格大小受衬底施加的外延应力的影响。在此实验的基础上，可以进一步对钴酸锶体系进行深入研究。

Transition metal oxides have rich functional properties, and there are lots of ways to control their physical properties. Among them, the control of the valence state of elements can achieve the control of the electrical and magnetic properties of materials, which has obtained extensive research interests. The strontium cobaltite system is rich in physical properties, and its properties will change obviously with the change of oxygen stoichiometry, such as Sr2Co2O5 with brownmillerite structure is an antiferromagnetic insulator, while SrCoO3 is a ferromagnetic metal with perovskite structure. In this paper, we studied the best growth conditions of Sr2Co2O5 using pulse laser deposition, through the ex situ ozone annealing, it was oxidized to SrCoO3. In order to study the crystal structure and symmetry of the films, the X-ray diffraction patterns and Raman scattering spectra of the films were measured. The Raman scattering spectra of Sr2Co2O5 are in good agreement with the theoretical results when its space group is Imma (74). The experimental results verify the films’ crystal structure and symmetry. By comparing the X-ray diffraction of Sr2Co2O5 samples grown on different substrates, we find that the lattice size of the samples is affected by the epitaxial stress exerted by the substrate. On the basis of this experiment, a lot of research on the strontium cobaltite system can be further explored.