Wafer-scale high-quality Ag thin film using a ZnO buffer layer for plasmonic applications

Monolayer-interface-driven strain-free heteroepitaxy for single-crystal Ag thin films

“…2e) exhibited only one spot corresponding to the (111) plane and the strict six-fold symmetry, the grown Ag lm was perfectly self-consistent with single-crystal Ag(111) as if it grew under no structural constraints. In contrast, conventional heteroepitaxy under high-strain conditions results in the grown lms usually exhibiting worse structural quality owing to the inevitable process of mis t strain accommodation and relaxation over the entire lm 3,19,28 . The surface of the Ag(111) lm inspected by SEM and atomic force microscopy (AFM) at different magni cations was smooth and grain boundary-free (Figs.…”

“…Owing to the promising application prospects of silver (Ag) lms for plasmonic devices, optical data storage, and re ectors [14][15][16][17] , signi cant research on large-scale single-crystal growth of Ag lms has been performed 13,[18][19][20][21][22] . However, because the tolerable range of lattice mismatches for heteroepitaxy using current approaches is insu cient for growing Ag lms (which typically require higher lattice mismatches), wafer-scale growth of defect-free Ag lms has not yet been achieved.…”

“…However, because the tolerable range of lattice mismatches for heteroepitaxy using current approaches is insu cient for growing Ag lms (which typically require higher lattice mismatches), wafer-scale growth of defect-free Ag lms has not yet been achieved. To overcome this fundamental barrier, a practical approach that considers an extended atomic distance mismatch (EADM) between two adjoining materials has been suggested 9,19,23,24 . For EADM values as low as approximately 0.1% for a certain long-range periodicity, grain boundary-free growth of copper (Cu) on-sapphire lms was demonstrated, even for atomic-distance mismatches exceeding 10% 24 .…”