TEMPERATURE SENSORS BASED ON SILICON NANOWIRES OBTAINED BY METAL-ASSISTED CHEMICAL ETCHING

Abstract

In this work, temperature sensors based on silicon nanowires (SiNWs), which were synthesized by the method of metal-assisted chemical etching (MACE), were manufactured and investigated. Resistive and diode sensors were obtained on the basis of SiNWs. The sequence of technological operations for the manufacture of temperature sensors was as follows: three-stage cleaning of the surface of silicon plates; metal-assisted chemical etching for the synthesis of SiNWs; diffusion for the formation of a p-n junction in nanowires; application of frontal and rear metallization. Electrical and thermosensitive characteristics were calculated for the obtained sensors: specific resistance, rectification coefficient, thermosensitive coefficients. The influence of MACE synthesis parameters on the electrical and thermosensitive characteristics of the sensors was studied. In particular, the influence of the presence of a texture on the surface of the silicon wafer, the duration of the first and second stages of MACE, additional processing in an isotropic/anisotropic etching, and removal of silver nanoparticle residues on the device characteristics was established. It was found that the maximum values of the thermal sensitivity of the resistive temperature sensor were observed for the textured substrate with additional treatment in acid etching (2851 ppm/K). For the diode-type temperature sensor, the maximum value of rectification coefficient was 676 and the maximum thermal sensitivity was 2.17 mV/K, which were observed for the non-textured substrate with additional treatment in acid etching.