Near zero-bias MIIM diode based on TiO2/ZnO for energy harvesting applications

• Published in: AIP advances Vol. 9; no. 11; pp. 115207 - 115207-8
• Main Authors: Elsharabasy, Ahmed Y., Alshehri, Abdullah H., Bakr, Mohamed H., Deen, M. Jamal, Musselman, Kevin P., Yavuz, Mustafa
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01.11.2019; AIP Publishing LLC
• Subjects: Algorithms; Aluminum; Atomic layer epitaxy; Bias; Current voltage characteristics; Diodes; Energy harvesting; Insulators; Optimization; Photolithography; Rectennas; Silicon dioxide; Substrates; Temperature dependence; Titanium; Titanium dioxide; Zinc oxide
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.5125255

Energy harvesting rectennas require ultrafast rectifying diodes that are efficiently matched to the optical nanoantenna. These diodes should possess low on-resistance and high responsivity. Here, we introduce a metal-insulator-metal diode composed of a new material, Ti-TiO2-Al. This diode has a 1.0 nm ultrathin insulator layer fabricated using atomic layer deposition (ALD). It has a zero-bias resistance of 275 Ω and a maximum responsivity of 3.1 A/W. To further improve its performance, another ultrathin layer of ZnO was added. The proposed Ti-TiO2/ZnO-Al metal-insulator-insulator-metal diode has a zero-bias resistance of 312 Ω and a maximum responsivity of 5.1 A/W. The two types of diodes are fabricated on a SiO2 substrate using conventional photolithography and ALD. Between 20 °C and 55 °C, the I-V characteristics did not show much temperature dependence. The effective barrier height, dielectric constant, and electron effective mass in each insulator are extracted using a constrained and derivative-based optimization algorithm.