Thin films of HfO_2 and ZrO_2 as potential scintillators

摘要

Emission, excitation and absorption spectra of HfO_2 and ZrO_2 thin films grown by atomic layer deposition were investigated in the temperature range of 10-300 K. Time-resolved luminescence spectra were excited with a pulsed ArF laser and tuneable synchrotron radiation in UV-VUV. The strong emission with the peak position at 4.2-4.4 eV and with the decay time in μs range was revealed at 10 K in both materials. The emission was ascribed to the radiative decay of self-trapped excitons (STE). the features observed in the absorption and excitation spectra at 5.8 and 5.4 eV were most probably due to the formation of excitons; While the interband transitions started to dominate at 6.15 and 5.85ev in HfO_2 and ZrO_2, respectively.