Effect of Multiple Frequency H2/Ar Plasma Treatment on the Optical, Electrical, and Structural Properties of AZO Films

Transparent conductive Al-doped zinc oxide thin films for film solar cells were prepared on Si and quartz substrates by radio frequency magnetron sputtering at room temperature. Then, these films were treated by high-density H₂/Ar plasma, which was capacitively coupled plasma combined with inductively coupled plasma modes. The density of hydrogen atoms was characterized by optical emission spectroscopy equipped in the system. The structural, electrical, and optical properties of the films were investigated in terms of spectrophotometry, Hall effect measurements, X-ray diffraction, scanning electron microscope, and atomic force microscopy. The effects of low-frequency power on the optical, electrical, and structural properties were discussed.