溶胶凝胶制备的铁酸铋基薄膜及其性能表征

Sol-Gel Prepared Bismuth Ferrate-Based Thin Films and Characterization of Their Properties

随着微电子工业的迅速发展,多铁性材料成为了材料科学与工程领域的研究热点。在众多铁电材料中铁酸秘(BFO)的应用前景是很广泛的,铁酸秘不仅是个无含铅绿色环保的多铁性材料,而且铁酸秘的制备温度低,有大的剩余极化值。但是它的制备非常困难,且由于Fe3+波动带来了大量氧空位,因此纯相BFO薄膜样品的漏电流较大。这也是一直以来困扰研究者的一个现实性问题。在此,我们使用了溶胶凝胶法和快速退火法,分别制备了掺杂Ce2+和Zn2+的Bi0.9Ce0.1FeO3 (BCFO)和BiFe0.9Zn0.1O3 (BFZO)薄膜以及共掺杂得到Bi0.9Ce0.1Fe0.9Zn0.1O3 (BCFZO)薄膜。并使用XRD和SEM技术研究制备薄膜的微观形貌和晶体结构,最后采用铁电测试仪在室温下对样品的电滞回线进行表征。结果表示掺杂以后的铁酸铋基薄膜因为抑制了氧空位而且降低了漏电流,所以铁电性能得到提升。这项研究证明了掺杂以后的薄膜具有良好的铁电性,本研究提供了提高铁电性的可行性方法以及铁酸秘薄膜为基础的多功能型应用器件的可用性。

With the rapid development of microelectronics industry, multiferroic materials have become a research hotspot in the field of materials science and engineering. Among many ferroelectric materials, the application prospect of BFO is very wide. BFO is not only a lead-free and environmentally friendly multiferroic material, but also has a low preparation temperature and a large residual polarization value. However, it is very difficult to prepare and the leakage current of pure phase BFO thin film samples is large due to the large number of oxygen vacancies brought by Fe3+ fluctuations. This is a realistic problem that has been troubling researchers. Here, we have prepared Bi0.9Ce0.1FeO3 (BCFO) and BiFe0.9Zn0.1O3 (BFZO) thin films doped with Ce2+ and Zn2+ as well as co-doped to obtain Bi0.9Ce0.1Fe0.9Zn0.1O3 (BCFZO) thin films by using a sol-gel method and a fast annealing method, respectively. The microscopic morphology and crystal structure of the prepared films were also investigated using XRD and SEM techniques, and finally the hysteresis lines of the samples were characterized using a ferroelectric tester at room temperature. The results indicate that the ferroelectric properties of the doped bismuth ferrite-based films are enhanced because of the suppression of oxygen vacancies and the reduction of leakage current. This study demonstrates that the doped films have good ferroelectricity, and this study provides a feasible method to improve the ferroelectricity and the availability of multifunctional application devices based on ferric acid secretion films.