Effect of Sm3+ on the structural, optical, magnetic and electrical properties of electrochemical deposition of ZnSe thin films

Abstract

Zn1−xSmxSe thin films with an Sm3+ concentration of x = 1 to 5 mole % were grown on ITO substrates at 50 °C using the electrochemical deposition (ECD) technique. The structural, optical, magnetic and electrical properties were analyzed as a function of the Sm3+ ion concentration. The glancing angle x-ray diffraction (GAXRD) characterisation of doped systems at various Sm3+ mole fractions x confirmed the exclusive formation of the host ZnSe with the zinc blende structure. The optical transmission spectra show that the percentages of transmission and band gap energy are different for pure and Sm3+ doped ZnSe thin films. Photoluminescence (PL) spectra of 1 to 5 mole % Sm3+ ion doped ZnSe thin films show two distinct ZnSe and Sm3+ related emissions, both of which are excited via the ZnSe host lattice. A sharp luminescence peak from Sm3+ doped ZnSe at 1.83 eV, which can be assigned as the 4G5/2 → 6H9/2 transition of Sm3+, was observed. The magnetization of Sm3+ doped ZnSe thin films was measured as a function of the magnetic field and temperature. The magnetic behaviour of magnetic semiconductor Sm3+ doped ZnSe, with no secondary phase, is reported. Electrical measurement showed that when the Sm3+ ion is incorporated, the electrical resistivity drops and the carrier concentration increases.