Physical characterization of 5′,5″-dibromo-o-cresolsulfophthalein (BCP) spin-coated thin films and BCP/p-Si based diode

The organic 5′,5″-dibromo-o-cresolsulfophthalein (BCP) compound thin films were deposited simply through spin coating technique from a pre-prepared solution of different molarities. Differential thermal analysis (DSC) and thermogravimetric analysis (TGA) of the starting powder compound were investigated to obtain the thermal stability and phase transformation of the compound. The structure, morphology, and optical properties were analyzed for all the prepared films of different molarities. Structural analyses revealed the nanocrystalline composition of all the prepared thin films. The resulted thin films nanostructure feature is verified by utilizing both the field emission scanning-electron-microscope (FESEM) and the high-resolution transmission electron microscope (HRTEM). Optical absorption exploration of BCP thin films was carried out in the limit of 200–2500 nm wavelength. The results revealed no changes in optical properties with molarity change. Al/p-Si/BCP/Au junction was prepared and investigated electrically in dark conditions and the diode parameters were extracted. The obtained diode can be employed in many applications such as rectifiers, clipper circuits, clamping circuits, reverse current protection circuits, logic gates, voltage multipliers, flexible electronics, and many other optoelectronic applications.