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

Single gamma-phase In2Se3 films were prepared by using metal-organic chemical-vapor deposition(MOCVD) with a single-source precursor [(Me)(2)In(mu-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, 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.