Highly efficient MIM diodes for NIR and SWIR applications

Official URL: http://dx.doi.org/10.1117/12.2304346

Metal-insulator-metal (MIM) diodes are highly considered in high frequency applications in form of rectennas for energy harvesting applications due to their fast speed, small size, and ease of fabrication and IC compatibility. In these diodes, insulators are integral part of the device, determining performance parameters. In this study, we have evaluated HfO2 and Al2O3 based MIM diode structures to compare and determine performance parameters, with conversion efficiency being prioritized. The fabrication processes in physical vapor deposition (PVD) systems for the MIM diodes resulted in the devices having high non-linearity and responsivity. Also, to achieve uniform and very thin insulator layer atomic layer deposition (ALD) was used. We implemented the same MIM structure in 10x10 array form, with active area of 200×325 nm2. The efficiency values of same arrays tested with 1200 and 1600 nm wavelength LEDs for 200×325 nm2 diode active area without applying bias. The conversion efficiency value of the HfO2 based structures calculated as 5% for 1200 nm wavelength. These measured values of conversion efficiency are reported for the first time in the literature for MIM diodes in SWIR operation.