End-Bonded Contacts of Tellurium Transistors

The development of novel low-dimensional materials makes the metallic contact to nanostructure facing challenges. Compared to side contacts, end-bonded contacts are proposed to be more effective pathways for charge injection and extraction. However, there is a lack of up-to-date understanding regarding end-bonded contacts, especially the recently emerged high-performance field-effect transistors (FETs). Here, the end-bonded contacts in tellurium (Te) transistors are first achieved by inducing metal semiconductor alloy. The formation of Pd-Te alloy structure is confirmed by a high-resolution transmission electron microscope (HRTEM) in Te-nanorod-based FETs. The ultralow specific contact resistance is estimated to be 5.1 × 10^-9 Ω cm² by the transmission line mode. On the basis of this finding, Te FETs are shown to exhibit incredible electronic properties, metal-insulator transition, and photodetection performance. This in-depth investigation of the end-bonded contact between Pd and Te speeds up the potential application of Te nanostructure and provides a feasible method for contact engineering in advanced devices.