Characterization of a 1024 × 1024 DG-BioFET platform

The use of biological field effect transistors (BioFETs) for the detection of biochemical events will yield new sensing systems that are smaller, less expensive, faster, and capable of multiplexing. Here, we present a novel massively parallel dual-gated BioFET (DG-BioFET) platform with over a million transistors in a 7 × 7 mm2 array that has all these benefits. Utilizing on-chip integrated circuits for row and column addressing and a PXI IC tester to measure signals, the drain current of each sensor in the 1024 × 1024 array is serially acquired in just 90 s. In this paper, we demonstrate that sensors in our massively parallel platform have standard transfer characteristics, high pH-sensitivity, and robust performance. In addition, we use the dual-gate operation and fast acquisition, unique in our platform, to improve the sensing performance of the system. We show that tailored biasing of the two DG-BioFET gates results in signal amplification above the Nernst limit (to 84 mV/pH) and redundancy techniques facilitate differential referencing, improving the resulting signal-to-noise ratio. Our platform encompasses the advantages of semiconductor-based biosensors, and demonstrates the benefits of high parallelism and FET dual-gate amplification for electrical and miniaturized biological sensing.