Effect of Temperature on the Electrical and Optical Properties of Silver (Ag) Assisted Electrochemically Etched Silicon Nanowires (SINWs)

The present work deals with the study of the effect of temperature on the Raman spectroscopy and electrical properties of the silicon nanowires. The nanowires are fabricated through silver assisted electrochemical etching process. Prior to these studies, the fabricated nanowires are characterized through field emission scanning electron microscopy (FESEM), field emission transmission electron microscopy (FETEM), and X-ray diffraction (XRD) measurements. FESEM reveals the vertical alignment of the nanowires. FETEM indicates the materials to be highly crystalline, which is also complemented by the XRD result. Raman peak is blue-shifted with a decrease of temperature suggesting lattice disturbance at low temperature. Temperature-dependent current-voltage (I-V) measurements are fitted with Cheung’s model and the characteristic parameters viz. ideality factor (n), barrier height (ϕ_b), and series resistance (R_s) are estimated from the fitted plots. At lower temperatures, the value of n highly deviates from the ideal value of unity and is 23.42 at 110 K. The materials are observed to obey space charge limited conduction (SCLC) to trap charge limit current (TCLC) with increasing bias at lower temperatures.