Tianjin Key Lab for Rare Earth Materials and Applications, Center for Rare Earth and Inorganic Functional Materials, Smart Sensor Interdisciplinary Science Center, School of Materials Science and Engineering, Nankai University, Tianjin 300350, China.
Center of Quantum Materials and Devices and College of Physics, Chongqing University, Chongqing 401331, China.
Nano Lett. 2022 Sep 28;22(18):7659-7666. doi: 10.1021/acs.nanolett.2c02891. Epub 2022 Sep 7.
BiOTe has the smallest effective mass and preferable carrier mobility in the BiOX (X = S, Se, Te) family. However, compared to the widely explored BiOSe, the studies on BiOTe are very rare, probably attributed to the lack of efficient ways to achieve the growth of ultrathin films. Herein, ultrathin BiOTe crystals were successfully synthesized by a trace amount of O-assisted chemical vapor deposition (CVD) method, enabling the observation of ultrahigh low-temperature Hall mobility of >20 000 cm V s, pronounced Shubnikov-de Haas quantum oscillations, and small effective mass of ∼0.10 . Furthermore, few nm thick CVD-grown BiOTe crystals showed high room-temperature Hall mobility (up to 500 cm V s) both in nonencapsulated and top-gated device configurations and preserved the intrinsic semiconducting behavior with / ∼ 10 at 300 K and >10 at 80 K. Our work uncovers the veil of semiconducting BiOTe with high mobility and brings new blood into BiOX family.
BiOTe 在 BiOX（X = S、Se、Te）家族中具有最小的有效质量和更优的载流子迁移率。然而，与广泛研究的 BiOSe 相比，对 BiOTe 的研究非常罕见，这可能归因于缺乏实现超薄薄膜生长的有效方法。在此，通过微量 O 辅助化学气相沉积（CVD）方法成功合成了超薄 BiOTe 晶体，从而观察到超高低温霍尔迁移率>20,000 cm V s、明显的舒布尼科夫-德哈斯量子振荡和约为 0.10 的小有效质量。此外，在非封装和顶栅器件配置中，厚度为数纳米的 CVD 生长的 BiOTe 晶体在室温下表现出高达 500 cm V s 的高霍尔迁移率，并且在 300 K 时保持了固有半导体行为，/约为 10，在 80 K 时>10。我们的工作揭示了具有高迁移率的半导体 BiOTe 的神秘面纱，为 BiOX 家族带来了新的血液。
