Toward spirometry-on-chip: design, implementation and experimental results

This paper presents a new approach towards the development of a spirometer-on-chip device for point-of-care diagnostics. The proposed device consists of a cantilever based airflow sensor fabricated through a multi-user MEMS process. The deflection of each cantilever beam is measured using capacitive electrodes integrated on a single semiconductor chip. These electrodes are connected to an off-chip custom-made readout interface circuit for the measurement of minute capacitive changes and for the acquisition of data into a computer. Herein, we discuss and demonstrate the characterization results of such a system using a low complexity air-based technique. Additionally, we demonstrate the applicability of these devices for spirometry on breathing tests of human subjects. Based on these results, the proposed spirometer-on-chip shows significant promise for use as a mobile portable system for continuous health assessment of respiratory health.