Demonstration of RF-DC conversion using dual diode rectifier circuit for rectenna with diamond Schottky barrier diodes

Dual diode rectifier circuits with two diamond Schottky barrier diodes (SBDs) for a rectifying antenna (rectenna) were fabricated for RF to DC conversion. A feature of diamond SBD structures is double NO₂ hole doping layers in order to form low Ohmic contact resistance and increase concentration of two dimensional hole gas at diamond surface. SBDs have good rectifier properties with on/off ratio larger than 5 orders. High current density of 24 A/cm² was obtained at the forward voltage of -2 V. A dual diode rectifier circuit with two diamond SBDs was constructed by selecting values of circuit components such as DC block capacitance and load resistance to make output voltage larger. In experimental, DC output voltage as large as 4 V was obtained for RF input voltage with 10 MHz and amplitude of 9 V.