Modeling, Fabrication, and Electrical Testing of Metal-Insulator-Metal Diode

摘要

We fabricated, tested, and modeled metal-insulator-metal (MIM) diodes for application into a nanorectenna energy-harvesting system. The MIM diodes were constructed of a niobium (Nb) bottom metal, niobium pentoxide (Nb2O5) dielectric, and varying top metals (copper, silver, and gold). Modeling and electrical testing were used to extract the dielectric constant of Nb2O5 as well as the metal-insulator barrier heights. The modeling also gave insight into the so-called rectification reversal, where the rectification polarity depends on which transport mechanism (thermionic emission or tunneling) dominates. Including an approximation for the image potential in the model was shown to be critically important in understanding the rectification reversal and quantitatively reproducing the measured electrical data. Future work will focus on verifying extracted barrier heights by photoemission techniques and exploring other material stacks. In addition, the dielectric thickness will be reduced and the temperature varied to further study tunneling dominated rectification.