Zn-induced impurity levels in layer semiconductor InSe

The impurity levels in Zn-doped InSe have been investigated by photoluminescence (PL), Hall effect (HE), and deep-level transient spectroscopy (DLTS). Previous analysis by PL spectra shows that the radiative transition is dominated by donor-Zn acceptor pairs. In the present work, a search was made for the deep acceptor level using the combined data from HE and DLTS measurements. We find that the deep acceptor level, which is associated with defects or defect complexes formed by Zn atoms in the interlayer, is located about 0.6 eV above the valence band.