Abstract: In order to improve the orientated growth of HgI₂ films in vapor,iso-epitaxy layers of polycrystalline mercuric iodide were deposited on ITO conductive glass by DSMO-HgI₂-H₂O solvent evaporation,polycrystalline HgI₂ films were then grown on iso-epitaxy layers by PVD.The films grew were investigated by SEM and XRD.The polycrystalline HgI 2 films detectors fabricated was studied by an uncollimated 241 Am radiative source with the principal energy of 59.5keV at room temperature.