Deposition-temperature effects on AZO thin films prepared by RF magnetron sputtering and their physical properties

作者：Park Jeung Hun^*; Shin Jong Moon; Cha Su Young; Park Jin Woo; Jeong Se Young; Pak Hyuk K; Cho Chae Ryung

来源：Journal of the Korean Physical Society, 2006, 49: S584-S588.

• AZO
• ZnO
• Al-doped ZnO
• RF magnetron sputtering
• transparent electrode

Transparent conductive thin films have attracted much attention due to their high conductivity and transmittance. In this paper, in order to find the optimal condition for fabricating optoelectronic devices, we investigated aluminum-doped zinc oxide (AZO) thin films prepared by radiofrequency (RF) magnetron sputtering on glass substrates by using a 2 wt.% of Al-doped ZnO target as a function of deposition temperature. The structural, electrical, and optical properties of AZO thin films were studied in terms of the deposition temperature. The crystal structure of AZO thin films had a hexagonal wurtzite structure and the orientation of the sample was along the c-axis, regardless of deposition temperature. The deposition temperature had influence on the average grain size and surface roughness, which could be confirmed by means of SEM and AFM. The average grain size increased with increasing deposition temperature. After increasing the deposition temperature, the surface of the AZO thin film improved but the root-mean-square (RMS) value of the surface roughness slightly increased. Also, the average transmittance of AZO thin films in the visible range (400 similar to 800 nm) was above 90 %. The optical band gap was dependent on the deposition temperature, and the value of the band gap of AZO thin films increased with increasing deposition temperature. The experimental results showed that the electrical resistivity of the AZO films deposited at room temperature (RT) and at 500 degrees C were 8.046 x 10(-4) Omega-cm and 1.297 x 10(-4) Omega-cm, respectively. Based on this work, we can find the best physical conditions of AZO thin films. Therefore, fabricated AZO thin films can be applied to transparent electrodes of OLEDs.

• 出版日期2006-12