Ni-DNA-based Thin-film NDR Device Development*

DNA is a natural one-dimensional nanowire; however, the low conductivity of DNA leads to the uselessness of nanodevices. To increase the conductivity of DNA, metal-doped DNA (M-DNA), such as Ni-DNA, has demonstrated its capability to be a new generation of conducting nanowires. In this study, we developed a flexible gold nano thin-film device by sputtering the gold on a PET substrate. The Ni-DNA could conjugate covalently via Au-S linkage. I-V curves of cyclic voltage scanning indicated that NDR effect and a hysteretic loop can be observed in this device. The NDR effect may be attributed to the Ni ion redox reaction taking place within Ni-DNA. These results indicated that the nano-thin-film Ni-DNA devices show similar I-V responses to the e-beam lithography nano-devices. Moreover, the non-Ni ion redox reaction currents at depletion region (~ +/- 2 V) of Ni-DNA device were observed after external bias +/- 6 V was applied. These results support the conducting mechanism of Ni-DNA which proposed in previous studies. In summary, a flexible device can be fabricated by using simple metal sputtering process, and the I-V responses indicated the Ni-DNA-based nano thin-film device might possess both memristor and memcapacitor behavior which can be used for mem-element electric system usage.