Zero-bias microwave detectors based on array of nanorectifiers coupled with a dipole antenna

• An array of nanodiodes has been developed to rectify RF signals at zero bias.
• The nanodiode array was fabricated at low cost, using only one lithography step.
• The device’s responsivity attained was ∼70 V/W with NEP of ∼0.18 nW/Hz1/2.
• The intrinsic responsivity can achieve up to ∼5 kV/W with NEP of ∼2.6 pW/Hz1/2.
• Zero-bias rectifiers offer low dc power consumption and low 1/f noise.

We report on zero-bias microwave detection using a large array of unipolar nanodevices, known as the self-switching diodes (SSDs). The large array was realized in a single lithography step without the need of interconnection layers, hence allowing for a simple and low-cost fabrication process. The SSD array was coupled with a narrowband dipole antenna with a resonant frequency of 890 MHz, to form a simple rectenna (rectifying antenna). The extrinsic voltage responsivity and noise-equivalent-power (NEP) of the rectenna were ∼70 V/W and ∼0.18 nW/Hz1/2, respectively, measured in the far-field region at unbiased condition. Nevertheless, the estimated intrinsic voltage responsivity can achieve up to ∼5 kV/W with NEP of ∼2.6 pW/Hz1/2.