Electrical and optical study of ITO films on glass and polymer substrates prepared by DC magnetron sputtering type negative metal ion beam deposition

Transparent, conducting indium tin oxide (ITO) films were deposited without intentional substrate heating on glass and polyethersulfone (PES) substrates by a magnetron sputter type negative metal ion source (MSNIS). The effect of substrate type on optical transmittance, electrical resistivity, surface morphology and roughness of the ITO film was analyzed. ITO/glass substrates show a higher optical transmittance (89%) and lower resistivity (4 × 10−4 Ω cm) than ITO/PES (78%, 6 × 10−4 Ω cm). X-ray diffraction (XRD) spectra indicate polycrystalline ITO films deposited on glass and amorphous ITO films on PES. Atomic force microscopy (AFM) images also indicate that ITO/glass has a lower surface roughness than ITO/PES. The values of figure of merit (T10/Rsh) for ITO/glass (ϕTC = 7.7 × 10−3 Ω−1) are higher than ITO/PES (ϕTC = 1.3 × 10−3 Ω−1), indicating that ITO/glass achieved the best performance in this study.