Tae-Kyung Gong

Effect of post-deposition annealing on the structural, optical and electrical properties of IGZO films

AbstractIGZO thin films were deposited on glass substrates via RF magnetron co-sputtering with In2O3 and GZO targets. The films were then vacuum annealed at 100°C, 200°C and 300°C for 30 minutes to investigate the effects of the annealing temperature on the structural, electrical, and optical properties of the films. Although XRD patterns demonstrated that all films had an amorphous phase regardless of annealing temperature, electrical resistivity decreased to as low as 3.2 × 10-4 Ω cm at an annealing temperature of 300°C. The optical transmittance in the visible wavelength region also improved from 80 to 83%. The figure of merit shows that IGZO films annealed at 300°C have the higher optical and electrical performance than other films prepared under different conditions in this study.

The Influence of Al Underlayer on the Optical and Electrical Properties of GZO/Al Thin Films

100 nm thick Ga doped ZnO (GZO) thin films were deposited with DC and RF magnetron sputtering at room temperature on glass substrate and Al coated glass substrate, respectively. and the effect of the Al underlayer on the optical and electrical properties of the GZO films was investigated. As-deposited GZO single layer films had an optical transmittance of 80% in the visible wavelength region, and sheet resistance of 1,516 , while the optical and electrical properties of GZO/Al bi-layered films were influenced by the thickness of the Al buffer layer. GZO films with 2 nm thick Al film show a lower sheet resistance of 990 , and an optical transmittance of 78%. Based on the figure of merit (FOM), it can be concluded that the thin Al buffer layer effectively increases the performance of GZO films as a transparent and conducting electrode without intentional substrate heating or a post deposition annealing process.