Some issues such as leakage current, tunneling current and light atom diffusion through the complementary metal oxide semiconductor transistors body, especially ultrathin gate dielectric, stoped people to use current element and gate dielectric for the CMOS generations. They have to find an alternative component of CMOS and optoelectronic devices. Some people have focused to organic materials as possible candidate for this demand. Phthalocyanines as possible semiconductor materials have been studied (Theoretically and experimentally) in the present work, which synthesized with sol-gel method with poly venial alcohol (PVA) and Nickel Phthalocyanine (NiPc) in three different concentrations (2.5, 5, 10, and 0.005, 0.01, 0.05), respectively. We examine the optical properties in order to meet the requirements for preparing in optoelectronic organic field transistor (OFET). These solutions are examined and characterized using UV–Vis inspection techniques. The findings indicate that as PVA (10 % in composites) and NiPC percentages (0.05%–5 % in composites) are increased, the conductivity coefficient, , is increased as well. Results indicate that optical conductivity and real, imaginary dielectric, and electrical constants all increase with concentration. We believe that phonons play main role due to composite atom's vibrations, so we need to consider indirect transitions. To our knowledge, the indirect transition for present composite with low band gap energy and phonon energy has not been reported before.
