The effect of substrates temperature on pentacene thin films prepared by organic thermal evaporator

The influence of substrate temperature on the physical and optical characteristics of pentacene thin films have been investigated by the experiment and using atomic force microscopy and UV- Visible spectrophotometer. The pentacene thin films were prepared on glass substrates by organic source evaporating system and the substrate temperature was varied between room temperature and 120degC. The results of AFM images and light absorbance indicate that the variation of substrate temperature has a distinguishable impact on both physical and optical properties of pentacene thin films. The AFM images show the increasing morphological grain size when the substrate temperature is risen. In addition, the thin films absorbance graph shown the dominant peaks at 1.82 eV, 1.97 eV, 2.14 eV 2.30 and 2.50 eV are all clearly diminished with increasing substrate temperature. The effect of substrate temperature on pentacene thin film properties are described in detail.