Enhanced electrical stability of flexible indium tin oxide films prepared on stripe SiO ₂ buffer layer-coated polymer substrates by magnetron sputtering

The electrical stability of flexible indium tin oxide (ITO) films fabricated on stripe SiO ₂ buffer layer-coated polyethylene terephthalate (PET) substrates by magnetron sputtering was investigated by the bending test. The ITO thin films with stripe SiO ₂ buffer layer under bending have better electrical stability than those with flat SiO ₂ buffer layer and without buffer layer. Especially in inward bending text, the ITO thin films with stripe SiO ₂ buffer layer only have a slight resistance change when the bending radius r is not less than 8 mm, while the resistances of the films with flat SiO ₂ buffer layer and without buffer layer increase significantly at r = 16 mm with decreasing bending radius. This improvement of electrical stability in bending test is due to the small mismatch factor α in ITO-SiO ₂ , the enhanced interface adhesion and the balance of residual stress. These results indicate that the stripe SiO ₂ buffer layer is suited to enhance the electrical stability of flexible ITO film under bending.