Optical Addressing Electronic Tongue Based on Low Selective Photovoltaic Transducer with Nanoporous Silicon Layer.

S V Litvinenko,V A Skryshevsky,D O Bielobrov,V Lysenko

doi:10.1186/s11671-016-1589-0

Abstract

The electronic tongue based on the array of low selective photovoltaic (PV) sensors and principal component analysis is proposed for detection of various alcohol solutions. A sensor array is created at the forming of p-n junction on silicon wafer with porous silicon layer on the opposite side. A dynamical set of sensors is formed due to the inhomogeneous distribution of the surface recombination rate at this porous silicon side. The sensitive to molecular adsorption photocurrent is induced at the scanning of this side by laser beam. Water, ethanol, iso-propanol, and their mixtures were selected for testing. It is shown that the use of the random dispersion of surface recombination rates on different spots of the rear side of p-n junction and principal component analysis of PV signals allows identifying mentioned liquid substances and their mixtures.

Highlights

Nowadays, the research and development of sensory systems like lab-on-a-chip [1, 2] for monitoring of toxic compounds in the atmosphere, water, food, and the identification of chemical composition of the outer space at all are becoming important task
One of the approaches in solving this problem is by using of large arrays of low selective semiconductor sensors
We present an experimental verification of new conception of an electronic tongue on the base of an array of low selective sensors that produce lightinduced photovoltaic signals (PV)

Summary

Introduction

The research and development of sensory systems like lab-on-a-chip [1, 2] for monitoring of toxic compounds in the atmosphere, water, food, and the identification of chemical composition of the outer space at all are becoming important task. The problem of the low selectivity makes the semiconductor sensor application very complicated. One of the approaches in solving this problem is by using of large arrays of low selective semiconductor sensors. It appeared during the researches of mammalian senses. Biological explorations show that high sensitive and selective mammalian organs of taste and smell consist of many low selective receptors of different types [3]. Such great selectivity is explained by the advanced signal treatment that is gained from the receptors’ array by the peripheral and central nervous system

Methods

Results

Conclusion