Barnard James P, Shen Jianan, Tsai Benson Kunhung, Zhang Yizhi, Chhabra Max R, Xu Ke, Zhang Xinghang, Sarma Raktim, Siddiqui Aleem, Wang Haiyan
School of Materials Engineering Purdue University West Lafayette IN 47907 USA.
Nanostructure Physics Sandia National Laboratories Albuquerque NM 87185 USA.
Small Sci. 2024 Jun 30;4(9):2400114. doi: 10.1002/smsc.202400114. eCollection 2024 Sep.
Magnetic and ferroelectric oxide thin films have long been studied for their applications in electronics, optics, and sensors. The properties of these oxide thin films are highly dependent on the film growth quality and conditions. To maximize the film quality, epitaxial oxide thin films are frequently grown on single-crystal oxide substrates such as strontium titanate (SrTiO) and lanthanum aluminate (LaAlO) to satisfy lattice matching and minimize defect formation. However, these single-crystal oxide substrates cannot readily be used in practical applications due to their high cost, limited availability, and small wafer sizes. One leading solution to this challenge is film transfer. In this demonstration, a material from a new class of multiferroic oxides is selected, namely bismuth-based layered oxides, for the transfer. A water-soluble sacrificial layer of SrAlO is inserted between the oxide substrate and the film, enabling the release of the film from the original substrate onto a polymer support layer. The films are transferred onto new substrates of silicon and lithium niobate (LiNbO) and the polymer layer is removed. These substrates allow for the future design of electronic and optical devices as well as sensors using this new group of multiferroic layered oxide films.
磁性和铁电氧化物薄膜长期以来一直因其在电子、光学和传感器领域的应用而受到研究。这些氧化物薄膜的性能高度依赖于薄膜的生长质量和条件。为了使薄膜质量最大化，外延氧化物薄膜经常生长在单晶氧化物衬底上，如钛酸锶（SrTiO）和铝酸镧（LaAlO），以满足晶格匹配并使缺陷形成最小化。然而，这些单晶氧化物衬底由于成本高、可用性有限和晶圆尺寸小，难以在实际应用中使用。解决这一挑战的一个主要方案是薄膜转移。在本演示中，选择了一类新型多铁性氧化物材料，即铋基层状氧化物进行转移。在氧化物衬底和薄膜之间插入一层水溶性牺牲层SrAlO，使薄膜能够从原始衬底释放到聚合物支撑层上。然后将薄膜转移到硅和铌酸锂（LiNbO）的新衬底上，并去除聚合物层。这些衬底有助于未来使用这组新型多铁性层状氧化物薄膜设计电子、光学器件以及传感器。
