Thickness dependences of the structural optical, and electrical properties of Cu2 Se thin films grown by using DC magnetron sputtering

The thickness dependences of the structural, optical, and electrical properties of p-type Cu2Se films have been investigated in the thickness range of 200–600 nm. X-ray diffraction analysis confirmed that a stoichiometric Cu2Se phase with a cubic structure was formed. From the Hall effect measurements, the electrical resistivity of the Cu2Se film showed a low resistivity of 4.21 × 10−5 Ω·cm. The optical band gap energy estimated from the optical transmittance measurements varied in the range from 2.01 to 2.41 eV at room temperature Moreover, the surface roughness of the film increased with increasing film thickness.