**4. Electronic devices (diodes and field effect transistors: FETs) based on single metal oxide nanowires**

In order to evaluate the electrical properties and to integrate single CuO or ZnO nanowires obtained by wet (chemical synthesis in aqueous solution) and dry (thermal oxidation in air) methods into electronic devices like diodes or field effect transistors, lithographic techniques and thin films deposition techniques were employed.

Firstly, photolithography together with radio-frequency magnetron sputtering and thermal vacuum evaporation were used to pattern Si/SiO2 wafers with Ti/Au (10 nm/100 nm) metallic interdigitated electrodes systems. Subsequently, suspensions of CuO or ZnO nanowires in ultrapure isopropyl alcohol are prepared by ultrasonication and then drop-cast onto the Si/SiO2 substrates patterned with Ti-Au metallic interdigitated electrodes. Afterwards, single CuO or ZnO nanowires are contacted by EBL, FIBID or EBL combined with FIBID. **Figure 7(a)** illustrates a SEM image of a Si/SiO2 substrate patterned with Ti/Au metallic interdigitated electrode system, while **Figure 7(b)** presents a SEM image of Ti/Au metallic interdigitated electrodes having metal oxide nanowires, transferred by drop-casting, between the Ti/Au electrodes.

The electrical measurements of the single CuO or ZnO nanowires contacted by lithographic techniques were carried out at room temperature in a typical twopoints configuration for diodes and a three-points configuration for FETs.
