title: Ratiometric, filter-free optical sensor based on a complementary metal oxide semiconductor buried double junction photodiode.
abstract: We report a complementary metal oxide semiconductor integrated circuit (CMOS IC) with a buried double junction (BDJ) photodiode that (i) provides a real-time output signal that is related to the intensity ratio at two emission wavelengths and (ii) simultaneously eliminates the need for an optical filter to block Rayleigh scatter. We demonstrate the BDJ platform performance for gaseous NH3 and aqueous pH detection. We also compare the BDJ performance to parallel results obtained by using a slew scanned fluorimeter (SSF). The BDJ results are functionally equivalent to the SSF results without the need for any wavelength filtering or monochromators and the BDJ platform is not prone to errors associated with source intensity fluctuations or sensor signal drift.
authors.affiliation: Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Ka Yi
authors.initials: KY
authors.lastname: Yung
authors.affiliation: Department of Biomedical Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Zhan
authors.affiliation: Department of Biomedical Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Albert H
authors.initials: AH
authors.lastname: Titus
authors.affiliation: Department of Chemistry, University of Missouri, Columbia, MO 65211-7600, USA.
authors.forename: Gary A
authors.initials: GA
authors.lastname: Baker
authors.affiliation: Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA. Electronic address: chefvb@buffalo.edu.
authors.forename: Frank V
authors.initials: FV
authors.lastname: Bright
mesh_terms: D000641:Ammonia / Q000032:analysis; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004867:Equipment Design; D005470:Fluorometry / Q000295:instrumentation / Q000379:methods; D006863:Hydrogen-Ion Concentration; D008670:Metals; D009284:Naphthols / Q000737:chemistry; D010087:Oxides; D038761:Photobleaching; D012235:Rhodamines / Q000737:chemistry; D012666:Semiconductors
chemical_list: D008670:Metals; D009284:Naphthols; D010087:Oxides; D012235:Rhodamines; C000605839:seminaphthorhodamine-1 carboxylate; D000641:Ammonia
keywords: Buried double junction; Complementary metal oxide semiconductor; Fluorescence; Integrated circuit; Ionic liquid; Sensing