Микрооптопара (λ = 3.4 μm) на основе двойной гетероструктуры InAsSbP/InAs для измерения концентрации этанола в водном растворе методом МНПВО

We discuss photoelectrical properties of an on-chip attenuated total reflection (ATR) sensor for the ethanol concentration measurements in an aqueous solution. The on-chip sensor/microchip was made from a p-InAsSbP/n-InAs monolithic double heterostructure with three mesas/individual diodes grown on a single n⁺-InAs substrate/waveguide. Two heterostructure diodes were used as photodiodes, while the third one - as a LED. The ethanol concentration was measured via an algorithm based on analysis of the I–V characteristic parameters of a photodiode and the L–I characteristics of an LED.