Liu Fengdeng, Yang Zhifei, Abramovitch David, Guo Silu, Mkhoyan K Andre, Bernardi Marco, Jalan Bharat
Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
School of Physics and Astronomy, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
Sci Adv. 2024 Nov;10(44):eadq7892. doi: 10.1126/sciadv.adq7892. Epub 2024 Nov 1.
Exploration and advancements in ultrawide bandgap (UWBG) semiconductors are pivotal for next-generation high-power electronics and deep-ultraviolet (DUV) optoelectronics. Here, we used a thin heterostructure design to facilitate high conductivity due to the low electron mass and relatively weak electron-phonon coupling, while the atomically thin films ensured high transparency. We used a heterostructure comprising SrSnO/La:SrSnO/GdScO (110), and applied electrostatic gating, which allow us to effectively separate charge carriers in SrSnO from dopants and achieve phonon-limited transport behavior in strain-stabilized tetragonal SrSnO. This led to a modulation of carrier density from 10 to 10 cm, with room temperature mobilities ranging from 40 to 140 cm V s. The phonon-limited mobility, calculated from first principles, closely matched experimental results, suggesting that room temperature mobility could be further increased with higher electron density. In addition, the sample exhibited 85% optical transparency at a 300-nm wavelength. These findings highlight the potential of heterostructure design for transparent UWBG semiconductor applications, especially in DUV regime.
超宽带隙（UWBG）半导体的探索与进展对于下一代高功率电子学和深紫外（DUV）光电子学至关重要。在此，我们采用了一种薄异质结构设计，由于电子质量低且电子 - 声子耦合相对较弱从而有助于实现高电导率，同时原子级薄膜确保了高透明度。我们使用了一种由SrSnO/La:SrSnO/GdScO(110)组成的异质结构，并应用了静电门控，这使我们能够有效地将SrSnO中的电荷载流子与掺杂剂分离，并在应变稳定的四方SrSnO中实现声子限制的输运行为。这导致载流子密度从10到10 cm调制变化，室温迁移率范围为40到140 cm V s。根据第一性原理计算得出的声子限制迁移率与实验结果紧密匹配，这表明随着电子密度的提高室温迁移率可能会进一步增加。此外，该样品在300 nm波长处表现出85% 的光学透明度。这些发现突出了异质结构设计在透明UWBG半导体应用中的潜力，特别是在深紫外领域
