Study Optical Properties Of Organic Thin Films And Its Application On Solar Cell

Abstract

Several advantages are available with organic semiconductors, including easy synthesis,straightforward purification, high solubility, inexpensive manufacture, and significantindustrial significance. Therefore, materials for large-scale electrical and optoelectronic devicesmade of organic semiconductors show promise. Therefore, studying the optical properties ofthese materials is very important not only for designing the devices, but also for knowing theirabsorption limits, determine the type of optical transition and the optical energy gap value toassess their viability for solar cell fabrication. For instance, we investigated the opticalcharacteristics of thin films of 4-dimethylaminobenzylidenemalononitrile (DBM). Through theprocess of thermal evaporation, the (DBM) thin films were created. Deposition was carried outon clean optical flat fused quartz substrates for optical measurements at room temperature andat two different thermal annealing temperatures of 323 and 373 K. Using a double-beam spectrophotometer, the transmittance T(λ) and reflectance R(λ) of DBM thin films with athickness of 480 nm were measured in the 200–2500 nm spectral region. It is possible todetermine the absorption index (k) and refractive index (n). Calculations were made for theoptical energy gap and Urbach energy at ambient temperature as well as at various thermalannealing temperatures (323 and 373K). It was found that the indirect energy gap increases withincreasing thermal annealing from 0.9325 eV for thin film as - deposited to 0.9575 eV at 373.The optical characteristics of DBM films can be changed by thermal annealing, which hasnumerous significant uses, including high-capacity communications networks.. This meansthat the material is suitable for use in manufacturing solar cells.