Abstract

We report on the formation of nonalloyed Ti and Ni ohmic contacts to ZnO films grown by pulsed-laser deposition. The experimental results show a lower barrier height of the Ti/ZnO samples than that of the Ni/ZnO samples (due to the lower work function of Ti than Ni), suggesting the Fermi-level unpinning at the interfaces. Based on the thermionic-emission or the thermionic-field-emission model, we found weak barrier-height dependence of the contact resistivity, implying that the presence of hydroxide in ZnO (i.e. the formation of the narrow depletion region at the metal/ZnO interface) resulted in the excess current component related to tunnelling, which led to the formation of the low-resistance nonalloyed metal/ZnO contact. The measurement temperature dependence of the contact resistivity revealed that the dominant current transport mechanism is field emission.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.