Pressure dependence of the photoluminescence from γ-In₂Se₃ thin films prepared using MOCVD with a single-source precursor

Abstract

Single γ-phase In₂Se₃ films were prepared by using metal-organic chemical-vapor deposition(MOCVD) with a single-source precursor [(Me)₂In(μ-SeMe)]₂. The basic physical properties of the grown films were examined by using X-ray diffraction, Raman spectroscopy, and photoluminescence spectroscopy at room temperature. The pressure dependence of the photoluminescence spectrum of the In₂Se₃ films was measured at room temperature. At 1 atm, 2 PL peaks were observed, one at 1.88 eV due to a bound exciton transition and the other at 1.50 eV due to a bound-to-free transition. While the pressure coefficients, $\frac{{dE}} {{dp}}|\begin{array}{*{20}c} {} \\ T \\ \end{array} \$ at pressures below 1.4 GPa were nearly zero, the pressure coefficients of both PL peaks at pressures above 1.4 GPa were −25 meV/GPa.