Generation of noise power at THz frequencies using CMOS schottky diodes in avalanche breakdown

Abstract

The viability of using CMOS schottky diodes in avalanche breakdown to generate noise power at THz frequencies was evaluated. Two sets of test diodes manufactured in TSMC's 65nm CMOS process were characterized in order to determine the optimal diode design for generating noise power. Measurements show that shallow trench insulation separated (STI) schottky diodes have nearly ideal breakdown characteristics while polysilicon gate separated (PGS) schottky diodes have poor breakdown performance due to the premature breakdown of fringe fields. Then two antenna arrays theoretically capable of radiating THz noise were designed using STI diodes. While measurements showed that these diodes are capable of generating up to 30 dB of additional noise power at low frequencies, no noise power was detected at THz frequencies in three separate measurement attempts. This work concludes with recommendations for future work to conclusively determine the viability of this approach.