Chemical Microsystem based on Vertical Integration of Sensor Array and CMOS Circuitry

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

This proposal focuses on the development of chemical sensing microsystems based on a vertical integration of microfabricated sensor arrays and CMOS circuitry. In the vertical integration approach, individual sensor chips or sensor arrays are bonded onto a common CMOS platform containing the biasing, signal conditioning and communication electronics. This way, circuitry and sensor elements can each be fabricated using the most appropriate technology. The vertical integration strongly increases the design flexibility, enables highly modular sensing systems whose components can be tested prior to the final assembly, while maintaining short signal paths between sensor array and circuitry. The proposed work addresses (i) the design and fabrication of mass-sensitive chemical sensor arrays and their driving and signal conditioning circuitry, (ii) the necessary process development for the vertical integration and system packaging, (iii) the characterization and localized deposition of different recognition membranes, and (iv) application testing of the microsystem. The latter focuses on the detection of toxic air pollutants and, in particular, the discrimination of chemically related volatile organic compounds. Intellectual Merit: The intellectual merit of the proposed work stems from the investigation of the limits of the proposed vertical integration in order to optimize the performance of miniaturized chemical sensing systems, leading to a better understanding of involved system aspects. The proposed screening of the membrane characteristics provides basic knowledge on the membrane/ analyte interaction and forms a base for future optimization of polymeric sensing membranes. Broader Impacts: The broader impact of the research project comes from the availability of the proposed chemical microsystem: (i) as an educational tool coupling state-of-the-art microfabrication, sensor technology and systems engineering aspects with applications in chemistry, biology and medicine, (ii) as a sensing platform applicable not only to the application tested in this work, but to a large number of today's chemical and biological sensing needs, and (iii) outreach activities to K-12 students.