Silicon Diode Structures Based on Nanowires for Temperature Sensing Application

Abstract

In this work, diode temperature sensors based on silicon nanowires (SiNWs) were fabricated. SiNWs were obtained by means of metal-assisted chemical etching of silicon (MACE). The surface morphology of silicon nanowires was studied by the scanning electron microscopy (SEM). The SEM results showed that a periodic array of silicon nanowires with a height of $4.9 \ldots 5.8\ \mu \mathrm{m}$ and a width of $k$ was obtained. The influence of MACE synthesis parameters on electrical and thermosensitive characteristics of the devices was studied. Obtained thermodiodes were studied in two different modes: constant current mode and constant voltage mode. It was found that the maximum values of the rectification ratio (1207) and thermal sensitivity (3 mV/K) were obtained for the deposition time of Ag-NPs of 20 s and the etching time of silicon of 90–150 min. For comparison, obtained rectification coefficient was 3 times higher, and thermal sensitivity was about 50% better than that of a silicon diode without SiNWs.