Metal-insulator-metal tunnel diodes on micro/nano antennas for energy harvesting and detector applications

There are open issues related to efficient rectifying device (diode) for effective applications on energy harvesting and detectors based on micro/nano antennas. Some technological approaches have been developed to improve diode performance at Terahertz (THz) and optical frequency regimes. Diodes based on Metal-Insulator-Metal (MIM) structure is one of the best candidates for this task, mainly due to its relative simple architecture, as well as its capability to achieve high frequency operations. The tunneling current mechanism is the main effect that allows fast diode performances. However, there are challenges related to the fabrication process, due to very low thickness of its insulator barrier, usually below 3 nm. Motivated by this, in this theoretical study we design MIM diodes based on very promising insulator for THz and optical frequency operations based on Zinc Oxide (ZnO), combining with Aluminum (Al), Zinc (Zn) and Copper (Cu) metals; we analyze some basic performance features, assuming variations of the insulator thickness. Results show a critical dependence of MIM diode performance on small variations of this parameter. Therefore, this study indicates the necessity of a strict control of the manufacturing parameters.