Elastically frustrated rehybridization: Origin of chemical order and compositional limits in InGaN quantum wells

TLDR

InGaN alloys have revolutionized lighting, delivering substantial energy savings. The study investigates the growth of single‑monolayer InGaN layers using tailored growth experiments, advanced characterization, and theoretical modeling. Self‑limitation of the films arises from a novel surface‑stabilization mechanism driven by elastically frustrated rehybridization. The films exhibit thickness‑ and composition‑self‑limitation and unique chemical ordering, and the mechanism explains these observations while enabling controlled homogeneous alloying.

Abstract

Solid state devices based on InGaN\penalty1000-\hskip0ptalloys have revolutionized lighting applications and have resulted in huge energy savings. Here, the authors investigate the growth of single monolayer InGaN layers by well-designed growth experiments, advanced characterization, and theoretical modeling. Specifically, they show that the growth of the InGaN films is self-limited with respect to thickness and chemical composition, but shows a unique chemical ordering absent in conventional InGaN films. The origin of the self-limitation is a novel surface stabilization mechanism---elastically frustrated rehybridization. The discovery of this new mechanism not only explains the origin of the experimental observations but provides also the basis for new strategies of controlled homogeneous alloying.