Effects of ion bombardment on the spectra of the edge photoconductivity and in the current–voltage characteristics of CdS crystals

The effect of ion bombardment in air on the electrical and photoelectric properties of CdS crystals at the boiling point of liquid nitrogen ($T$ = 77 K) has been investigated. It is shown that the bombardment of crystals leads to a significant increase in the photosensitivity in the region of the absorption edge, as well as to an increase in their dark conductivity. At the same time, the quantitative changes in the dark conductivity significantly exceed the changes in the photosensitivity of all studied samples. The observed changes in the fine (excitonic) structure indicate the surface nature of the effect of ions on the semiconductor. The observed changes are associated with surface doping of the investigated semiconductors by donors using ion bombardment. The applied bombardment technique can be used for practical purposes in order to modify the electrical properties of semiconductors belonging to the А$^{\mathrm{II}}$В$^{\mathrm{VI}}$ compounds.