The photodetection characteristics of a Brilliant Blue-FCF implemented device for organic-based optoelectronic applications

Abstract

The optical properties of sol-gel-based brilliant blue-FCF (BB-FCF) thin film are analyzed for photodetection applications. The effect of the presence of the BB-FCF interface on the microelectronic characteristics of the designated Cu/BB-FCF/n-Si device is elucidated by comparing to its reference Cu/n-Si device. The systematic investigation of photodetection properties of the integrated device is performed between the 20–100 mW/cm2 illumination intensities. First, the optical features of spin-coated BB-FCF thin film are investigated by UV–Vis measurements, and the absorbance of the film is elucidated by the efficient optical absorption in the wavelength of ∼350–700 nm with the calculated optical indirect band gap of 1.72 eV. Next, the frequency-dependent capacitive behavior, charge transport mechanism, and the electronic parameters of both the rectifying Cu/n-Si and the implemented Cu/BB-FCF/n-Si devices like the ideality factor, the barrier height, and series resistance are estimated using the Thermionic emission and Norde's function methods. Subsequently, the photodetection properties of the engineered device with a BB-FCF functional dye interface are studied under a solar simulator with different power intensities. The effect of the illumination intensity and applied reverse bias voltage on the figures of merit, including photoresponsivity, photodetectivity, response speed, and linear dynamic property, are analyzed under an illumination of 20–100 mW/cm2. The designated device with a BB-FCF interface has achieved significant and fast, stable on/off switching sensitivities, with 524 ms and 629 ms rising and falling times, respectively. Therefore, the prepared BB-FCF-based device has good and stable photoresponse performance, and the Cu/BB-FCF/n-Si architecture device may be a strong candidate for photonic and optoelectronic device applications, particularly in rapidly developing organic material-based device technology.