Optically powered energy source in a standard CMOS process for integration in smart dust applications

Abstract

In order to miniaturize nano-power sensor nodes or smart dust, an optically powered energy source is developed to replace traditional batteries or solar cells. This energy source consists of two photodiodes, which are P-well/DN-well and N-well/P-sub. The two photodiodes with an area of 1.5mm2 were fabricated using the UMC 0.25μm CMOS process and tested using an 830nm laser. Measurement results show that the energy source is able to generate a voltage from 0.5V to 0.8V with a 3.5% conversion efficiency. The proposed energy source was made using a standard CMOS process and therefore can to be integrated with the smart dust circuit on a single chip.