Passive DNA Sensor with Gold Electrodes Fabricated in a CMOS Backend Process

A sensor for electrical detection of DNA is fabricated in a CMOS production line. A gold deposition process module is integrated in a CMOS backend process. The sensor principle is based on immobilization of singlestranded DNA probe molecules on an array consisting of interdigitated gold lines and subsequent hybridization with labeled target DNA strands. The electrical signal results from an electrochemical redox cycling process. Successful DNA detection experiments on the basis of such ‘passive’ chips are performed. This passive arrangement represents a test run for the extension of this principle to develop fully electronic DNA sensor arrays on active CMOS chips.