Characterization and performance evaluation of nanostructured rod-like CdTe/Si fast-response visible light photodetector

Abstract

Nanostructure rod-like cadmium telluride (CdTe)/Si fast-response visible light photodetector was fabricated under diverse energies using pulsed laser deposition approach. The interdependence between structural and optical features along with in-depth photodetection evaluation was thoroughly demonstrated. Particularly, augmented photocurrent (Iph) behavior was observed (68.9–92.3 μA) at energy of 140 mJ and 220 mJ, respectively; such occurrence was noticed under illumination of 575 nm and 6 mW/cm2. This was accomplished along bandgap alteration of 0.07 eV and rod-like diameter of 70.12 nm. In conjunction, the optimum geometry (@220 mJ) responded well to incident wavelength range with maximum responsivity (Rλ) of 15.38 mA/W at 575 nm, around which lower profile was perceived. The incident power revealed positive linear correlation (R2= 0.989) with Iph at which values of 92.3 and 183.3 μA were achieved under 6 and 26 mW/cm2, respectively. The time-dependent characteristics demonstrated response-time of 90.8 ms. evidencing fast-response aspect of the optimum device.