Compacted nanoscale sensors by merging ZnO nanorods with interdigitated electrodes

摘要

ZnO nanorods (NRs) sensors utilizing hybrid or monolithic integration of the NRs on nanoscale or microscale interdigitated electrodes (IDEs) were fabricated and characterized. The IDEs with their finger electrode width ranging from 50 nm to 3 μm were formed on SiO2/Si substrates by nanoimprint lithography or conventional photolithography and metallization techniques, whereas the ZnO NRs were grown by chemical synthesis method. The average diameter of the ZnO NRs is about 100 nm, and their length can be varied from 2 to 5 μm by controlling growth time. When sensing targets, such as molecules or nanoparticles, bind onto the ZnO NRs, the conductance between IDEs will change. As probing test, II-VI quantum dots (QDs) were attached on the ZnO NRs, and clear responses were obtained by measuring and comparing current-voltage (I-V) characteristic of the sensor before and after binding the QDs.