Study of microwave circuits based on Metal-Insulator-Metal (MIM) diodes on flex substrates

This paper demonstrates fabrication and characterization of thin-film Ti-TiO₂-Pd based Metal-Insulator-Metal (MIM) diodes on flexible substrates. MIM diodes with contact areas of 9 μm² and 48 μm² were fabricated, and a comparison is made for their DC and RF performances. The current-voltage characteristics of the fabricated diodes show strong non-linearity. The diodes are also tested for microwave circuit applications such as detection, frequency multiplication and mixing over a frequency range of 1-18 GHz. The devices show strong second harmonic frequency multiplication for fundamental frequencies of 1-10 GHz. Details of DC characteristics, RF rectification, mixing and multiplication using MIM diodes are presented.