Atomic-Precision Repair of a Few-Layer 2H-MoTe Thin Film by Phase Transition and Recrystallization Induced by a Heterophase Interface.

2D semiconductors have emerged as promising candidates for post-silicon nanoelectronics, owing to their unique properties and atomic thickness. However, in the handling of 2D material, various forms of macroscopic damage, such as cracks, wrinkles, and scratches, etc., are usually introduced, which cause adverse effects on the material properties and device performance. Repairing such macroscopic damage is crucial for improving device performance and reliability, especially for large-scale 2D device arrays. Here, a method is demonstrated repair damage to few-layer 2H-MoTe films with atomic precision, and its mechanism is elucidated. The repaired 2H-MoTe inherits the lattice orientation of the adjacent original 2H-MoTe , thereby forming an atomically perfect lattice at the repaired interface. The time-evolution experiments show that the interface between the 2H- and early formed 1T'-MoTe plays an important role in the subsequent phase transition and recrystallization. Electrical measurements on the original MoTe , repaired MoTe , and cross-interface regions show unobservable differences, indicating that the repaired MoTe has the same electrical quality as the original one and the interface does not introduce extra scattering centers for carrier transport. The findings provide an effective strategy for macroscopic damage repair of few-layer 2H-MoTe , which paves the way for its practical application in advanced electronics and optoelectronics.