Quantitative Measurement of Colorimetric Signals in 180nm Standard CMOS Technology

Abstract

In this work, a CMOS based optical read-out system for biomarker sensing is presented. An integrated circuit containing an on-chip photodiode is designed an manufactured in 180nm UMC CMOS Technology. A 3D Printed structure is designed for holding both IC and the marker paper together. Laser light with 637 nm wavelength is applied to the marker paper and the CMOS IC. Optical measurements carried-out are based on the light transmissivity of the marker paper. Both photovoltaic and photoconductive measurements are carried out. The markers are successfully detected with 5mW to 20mW optical power. Images of the marker lines with varying intensity are generated from the measurements. Lastly, theoretical equations are derived, and the feasibility of the system for low power biomarker sensing applications is shown.