Structural and Optical Properties of TIPS Pentacene Thin Film Exposed to Gamma Radiation

This study investigates the effects of Gamma-irradiation on the structural, morphological and optical properties of 3,16-bis(tri isopropyl silylethynyl)pentacene (TIPS Pentacene) organic semiconductor films. The TIPS Pentacene thin films were irradiated at 10 to 300 kGy at a dose rate of 1.58 kGy/hr. The films were characterized using X-Ray Diffractometer (XRD), Atomic Force Microscopy (AFM) and Ultraviolet-Visible Spectroscopy (UV-Vis). The XRD analysis showed that the pre-irradiated thin films were of crystalline structure, indicating a broad wave diagram. The XRD and AFM results show that these variations can be attributed to the radiation-induced local heating and microscopic atomic mobility. Based on the UV-Vis results, the thin films exhibit approximately 70% optical transmittance in the visible region at pre-irradiation. At post-irradiation, optical transmittance decreased to 55% at the maximum absorbed dose. The corresponding optical bandgap decreased from 1.87 to 1.50 eV after a total ionizing dose of 300 kGy. The findings showed that TIPS Pentacene thin film has good mitigation towards gamma irradiation and can withstand harsh radiation while retaining its semiconductor properties. It is a potential candidate for flexible electronics for space applications.

Keywords:
TIPS Pentacene; gamma radiation; radiation effects; organic semiconductor