GaN in different dimensionalities: Properties, synthesis, and applications

Wurtzite GaN materials underpin many aspects of optoelectronic applications due to the special tetrahedral-coordinated structure. Compared with three dimensional (3D) GaN, low dimensional GaN provides structural and electronic changes, such as different geometrical configuration, surface trapped states and quantum confinement effect, which impose dramatic effects on the properties and even the ultimate applications. To construct desirable devices and expand the scope of applications for GaN, it necessitates an in-depth understanding of the dimensionality-dependent property. In this review, we firstly review the structure and properties of GaN in different dimensionalities. Successively, strategies for realizing the synthesis of GaN with various dimensionalities are generalized. Afterwards, we examine how their structure and properties are utilized in the significant applications involving microelectronic devices and energy conversion fields. Finally, we conclude by outlining a few research directions of GaN semiconductors that might be worthwhile for exploration in the future.