Wafer-Scale (100)-Oriented Te Single-Crystalline Thin Films with Exceptional Electronic and Photodetection...

Te displays the potentials in chirality, anisotropic electronics, and optoelectronics owing to its unique chiral chain lattice structure. However, the specifically oriented growth is still challenging thanks to a lack of lattice-matched substrates. Herein, (100)-oriented Te single-crystalline films are grown via a van der Waals epitaxial (vdWE) mode. Wafer-scale and high-crystal quality with a low full width at half maximum (0.25°) and an ultrahigh hole Hall mobility (1267.2 cm²V^-1s^-1) are yielded in the 58.2 nm. In-plane anisotropic transport is present in these vdWE films, and exceptional current switching is displayed in the ones below 21.3 nm. Photoresponse performance increases with the film thickness while the polarization effect is absent above the 23.5 nm. Broadband detection from 420 to 2000 nm is demonstrated. Peak responsivity, detectivity, and external quantum efficiency reach 2.97 × 10⁴ A/W, 1.21 × 10¹³ Jones, and 7.12 × 10⁴% at 520 nm in the 58.2 nm field-effect transistor (FET). Dual-symmetric polarization effect is revealed in the 11.2 nm FET detectors with a polarization ratio of 1.11 at 1650 nm and 1.04 at 638 nm. This work presents a scalable growth route for (100)-oriented Te and highlights the potential in integrated, high-speed, and polarized devices.