Comparison of organic diode structures regarding high-frequency rectification behavior in radio-frequency identification tags

In this article, we compare the direct current (dc) and high-frequency performance of two different organic diode structures, a vertical diode and an organic field effect transistor (OTFT) with shorted drain-gate contact, regarding their application in a rectifying circuit. For this purpose, we fabricated both diode structures using the organic semiconductor pentacene. dc measurements were performed showing a space-charge-limited current mobility of more than $0.1{\mathrm{cm}}^2∕\mathrm{V}\mathrm{s}$ for the vertical diode and a field effect mobility of $0.8{\mathrm{cm}}^2∕\mathrm{V}\mathrm{s}$ for the OTFT with shorted source-drain. High-frequency measurements of those diode structures in a rectifier configuration show that both types of diodes are able to follow the base-carrier frequency of $13.56\mathrm{MHz}$ which is essential for viable radio-frequency-identification (rf-ID) tags. Based on those results we evaluate the performance limits and advantages of each diode configuration regarding their application in an organic rf-ID tag.