Люминесценция тонких пленок Hf-=SUB=-x-=/SUB=-Zr-=SUB=-1-x-=/SUB=-O-=SUB=-2-=/SUB=- при возбуждении синхротронным излучением вакуумного ультрафиолетового диапазона

Abstract

Using the methods of low-temperature luminescence spectroscopy and vacuum ultraviolet synchrotron radiation (MAX IV synchrotron, Lund, Sweden), charge transfer processes and the nature of charge carrier traps responsible for leakage currents in nanometer dielectric films of hafnium-zirconium-oxygen solid solutions on silicon substrate, as well as in films doped with La-ions and annealed in argon atmosphere. The photoluminescence spectra, photoluminescence excitation spectra of the 2.7 eV emission band and previous simulation data within the framework of density functional theory confirm the presence of an oxygen vacancy in the studied films. Based on the study of competing channels for the relaxation of electronic excitations due to the radiative decay of self-trapped excitons (4.35 eV emission band) and the luminescence of defects (2.7 and 3.5 eV emission bands), a conclusion was made about the efficiency of transport and capture of excitons and separate charge carriers in films with varying degrees of defectiveness and films doped with lanthanum. The obtained data confirm the conclusion that oxygen vacancies are traps responsible for leakage currents in the films under study.