Wafer-scale single crystals: crystal growth mechanisms, fabrication methods, and functional applications

Abstract

Wafer-scale single crystals, by virtue of their intrinsically high crystallinity and compatibility on a wafer-scale processing size, have been extensively studied and applied in various electronics and optoelectronics. In this review, we present relevant challenging issues on controllable preparation, additive patterning, and heterogeneous integration of functional single crystals with uniform morphology and unitary crystallographic orientation at the wafer scale. Furthermore, substantial efforts on wafer-scale fabrication of single-crystal films (or isolated single-crystal arrays) through innovative growth strategies are summarized, especially highlighting the impact of nucleation and the growth kinetics on crystal formation. We also outline the distinctive characteristics of single-crystal organic semiconductors, perovskites, and 2D semiconductors, rendering their various (opto)electronic applications. Finally, we discuss potential problems and the outlook of promising research directions of wafer-scale single crystals and their devices for next-generation (opto)electronics.