Authors: Mengzhuan Lin, Luocheng Liao, Dirui Wu, Youna Huang, Jianxing Wu, Linkun Wang, Wanting Xu, Yuan Zhang, Jiahao Song, Yingli Zhang, Changjian Li
Published: 2025-04-28
Source: Full article
AbstractBi2O2Se has recently attracted immense interest in nanoelectronics and optoelectronics for its superior mobility, ferroelectric order, tunable bandgap, and exceptional air stability. However, until now, the direct growth of Bi2O2Se is limited to mica, or perovskite oxide substrates [SrTiO3, LaAlO3, (La, Sr)(Al, Ta)O3], incompatible with mainstream semiconductor processes, and the room temperature mobility is limited to ≈800 cm2 V−1 s−1. Here, the controllable growth of Bi2O2Se nanoflakes on SiO2/Si substrates is reported and with room temperature electron mobility higher than 2000 cm2 V−1 s−1, exceeding all previous reports. The unpreceded in‐plane electron mobility is found to strongly correlate with the out‐of‐plane ferroelectric order, which is stabilized by the expanded c‐lattice in oxygen‐deficient Bi2O2Se. The stabilized ferroelectric phase is confirmed by piezoresponse force microscopy (PFM) and anisotropic transport property measurements, which generally possess a high dielectric constant, thus reducing the impurity scattering. The silicon‐compatible ultrahigh mobility Bi2O2Se sheds light to high‐performance electronic devices.