Fabrication and characterization of wide band gap semiconductor for ultraviolet sensing based on nanoparticles ZnO and bulk SIC

The aim of the project described in the following consists on the fabrication, optimization and characterization of ultraviolet (UV) photodetectors based on wide band gap (WBG) semiconductors. The fabrication will imply devices based only zinc oxide (ZnO) nanoparticles based devices. The process consist of wafer level patterning of metallic electrodes to contact the ZnO nanoparticle film. The last step performed involves the deposition of the metal nanoparticles through the combination of spark ablation and impaction printing technology trying to create a conductive path between electrodes at die level. The obtained devices undergo a thermal treatment in order to fully oxidize the zinc particles and thus obtaining only a zinc oxide phase, taking into account the temperature effect on the metal electrodes. A morphology analysis has been carried out to understand the roughness and porosity of the film deposited, but anyhow their relevance for the purpose of the material is not really effective for the photodetection mechanism. An electrical characterization of the devices obtained, and other already fabricated photodiode based on silicon carbide SiC. The performances of ZnO samples has been tested in different operating conditions (temperature and light effect). Optical characterization involves both the devices based on the WBG semiconductor which imply the measurement of the optical response of the DUT stimulated by different monochromatic light, then the evaluation of the response time. Finally, we will sum up with the final data and importance aspects to take into account regarding the production method and performances showing their benefits and drawbacks.