Abstract:
PbS nanodots embedded in ZrO2 thin film matrix (ZrO2:PbS films) were studied for application
in nanodosimetry of electron radiation used in radiation therapy. ZrO2:PbS films were irradiated with
9 MeV electron radiation with doses 3, 7 and 10 Gy using medical linear accelerator. Detection of the
dosimetric signal was made by measuring and comparing photoelectron emission current from ZrO2:PbS
films before and after irradiation. It was found that electron radiation decreased intensity of photoemission
current from the films. Derivatives of the photoemission spectra were calculated and maximums at photon
energies 5.65 and 5.75 eV were observed. Amplitude of these maximums decreased after irradiation with
electrons. Good linear correlation was found between the relative decrease of the intensity of these
maximums and dose of electron radiation. Observed changes in photoemission spectra from ZrO2:PbS films
under influence of electron radiation suggested that the films may be considered to be effective material for
electron radiation dosimetry. Photoelectron emission is a tool that allows to read the signal from such
dosimeter.