An Integrated Low Temperature Co-Fired Ceramic-Based Clark-Type Oxygen Sensor

Abstract

Low temperature co-fired ceramic (LTCC) electronic packaging materials are applied for the advantages of their mechanical durability, low cost, flexibility of the layered manufacturing, and capability to integrate both electronic and microfluidic functions in a single LTCC module. Clark-type oxygen sensors are electrochemical devices that are widely used for sensing dissolved oxygen in biological applications. In this paper, a Clark-type oxygen sensor has been developed using the LTCC thick-film technique instead of the traditional silicone/glass micromachining, and it consisted of an LTCC substrate with three electrodes (working electrode, counter electrode, and Ag/AgCl reference electrode), a polydimethylsiloxane (PDMS) oxygen permeable membrane and a PDMS reservoir. The fabricated Ag/AgCl reference electrode demonstrated high density with longtime stability. Cyclic voltammetry and chronoamperometry were measured to evaluate the electrochemical properties of the LTCC-based Clark-type oxygen sensor. The reduction current had a linear relationship with oxygen concentration. Meanwhile, the LTCC-based Clark-type oxygen sensor exhibited comparative performances, including low residual current, <;5%, and fast response time, 7.5 s, compared with the literatures.