Graduate School of Information Science and Technology, Hokkaido University, N14W9, Kita, Sapporo 060-0814, Japan.
Research Institute for Electronic Science, Hokkaido University, N20W10, Kita, Sapporo 001-0020, Japan.
Dalton Trans. 2023 May 16;52(19):6317-6323. doi: 10.1039/d3dt01097j.
La-doped BaSnO (LBSO), which exhibits both high electron mobility and visible-light transparency, is a promising transparent electrode/transistor material that does not require expensive elements such as indium. However, because a high crystal orientation is necessary for high mobility, the development of a synthetic technique is crucial for next-generation optoelectronic applications. One promising method for achieving this is the lift-off and transfer method. Epitaxial films are first deposited on single-crystal substrates, peeled off from the substrates, and subsequently transferred onto other substrates. However, such transferred sheets typically contain a high density of cracks. Therefore, LBSO sheets with flexibility, high mobility, and transparency have not yet been reported. In this study, we successfully synthesized crack-free LBSO epitaxial sheets a lift-off and transfer method using a water-soluble SrAlO sacrificial layer and amorphous (a-)AlO protection layer. The LBSO sheet simultaneously exhibited a high electron mobility of 80 cm V s and a wide optical bandgap of 3.5 eV owing to the epitaxial crystallinity of the sheet. Moreover, two types of LBSO sheets were prepared, flat and rolled sheets, by tuning the lift-off process. The flat sheet had a lateral size of 5 mm × 5 mm, whereas the rolled sheet had a tube shape with a height of 5 mm and a diameter of 1 mm. Such large crack-free area and flexibility were achieved in LBSO sheets owing to the use of the a-AlO protection layer.
掺镧的 BaSnO（LBSO）具有高电子迁移率和可见光透明度，是一种很有前途的透明电极/晶体管材料，不需要昂贵的铟等元素。然而，由于高迁移率需要高的晶体取向，因此开发合成技术对于下一代光电子应用至关重要。一种很有前途的方法是剥离和转移方法。首先在单晶衬底上沉积外延膜，从衬底上剥离下来，然后转移到其他衬底上。然而，这样的转移片通常含有高密度的裂纹。因此，具有柔韧性、高迁移率和透明度的 LBSO 片尚未报道。在这项研究中，我们成功地使用水溶性 SrAlO 牺牲层和非晶(a-)AlO 保护层通过剥离和转移方法合成了无裂纹的 LBSO 外延片。由于片的外延结晶性，LBSO 片同时表现出 80cm V s 的高电子迁移率和 3.5eV 的宽光学带隙。此外，通过调节剥离过程，制备了两种类型的 LBSO 片，即平整片和卷曲片。平整片的横向尺寸为 5mm×5mm，而卷曲片呈管状，高度为 5mm，直径为 1mm。由于使用了 a-AlO 保护层，LBSO 片中实现了如此大的无裂纹区域和柔韧性。
