The immobilization and electrical response of single-stranded DNA molecules on pentacene transistors

The immobilization and electrical response of single-stranded deoxyribonucleic acid (ssDNA) on pentacene-based transistors have been studied. The result displays that ssDNA molecules may be well immobilized onto pentacene film surface observed by atomic force microscopy. The device parameters of transistors including drain-source current and threshold voltage exhibit an obvious change by comparing with pristine transistors that can be attributed to the additional positive charges induced by immobilized ssDNA molecules. Furthermore, the dependence of electrical response on the ssDNA solution concentration was disclosed.