Graphenea has introduced two new GFET (graphene field-effect transistor) sensing devices, aimed at customers with biosensing requirements. Both devices are designed for measurements in a liquid medium.
The GFET-S21 is a modification of the S20. It contains 12 graphene devices connected in parallel, with encapsulation over the metal contact pads to avoid long-term degradation and to reduce leakage currents. There is also a large, non-encapsulated electrode across the center of the chip, which allows liquid gating without needing an external gate electrode. Due to the parallel connection of many devices, this architecture enhances signal-to-noise ratio and reduces parasitics. The averaged signal is more robust compared to using just a single graphene device, also allowing for driving larger currents (~mA) through the chip, which eases integration with standard measurement electronics.
The GFET-S22 also contains 12 devices, however they are grouped in 4 sets of 3 graphene channels. The S22 is aimed for users who wish to functionalize each set with a different biomarker, for multiplexed biosensing, or for “electronic nose” applications in gas sensing, where each set responds to a different analyte.
These new GFET architectures that can now be ordered from the Graphenea store complement the established GFET devices such as the S10, S11, S12, S20, and GOFET. Each of these architectures is designed with a specific customer requirement in mind, although they are all aimed at lowering the entry barriers to graphene sensor research. Custom chip designs are also available upon request through our Graphene Foundry service.