Vliyanie tolshchiny inkapsuliruyushchikh sloev na kachestvo geterostruktur na osnove MoSe2

Abstract

The dependence of the width of exciton and trion photoluminescence lines in MoSe2 monolayers on the thickness of hexagonal boron nitride encapsulating layers has been investigated. The possibility of variation of the exciton photoluminescence linewidth due to the interaction of excitons with the modes of resonator cavities made up of a silicon substrate and a boron nitride top layer has been checked. This interaction may significantly change the photoluminescence linewidth owing to the Parcell effect. Measurements taken of samples with different thicknesses of the bottom and top boron nitride layers have not revealed any influence of the Parcell effect on the linewidth. It has turned out however that the linewidth narrows by several times with increasing boron nitride bottom layer thickness from 10 to 100 nm and reaches 2 meV at a thickness of 100 nm. Supposedly, such narrowing of the photoluminescence line is associated with a decrease in the density of submicron bubbles, which takes place at longitudinal stress relaxation in the thicker layer of boron nitride.