Graphenea has introduced two new products to ease the work of customers who perform research into graphene-based sensors. The products, named S11 and S12, build upon the existing “GFET for sensing” product lineup, which is designed with the needs of customers in mind.
The GFET-S11 chip houses 31 graphene devices with a van der Pauw (vdP) geometry, distributed in three different sizes – three with a 2x2mm2 footprint, fourteen with a 500x500µm2 footprint, and fourteen with a 125x125µm2 footprint. The vdP geometry is an alternative to Hall Bars, which are provided through the GFET-S10 product. Both geometries are used for precise measurements of current in graphene devices. Supplying both geometries will work in favour of the customers, as there are research groups that have a setup optimised for Hall bar configuration, whereas others are accustomed to vdP. The availability of various graphene device dimensions on one chip allows investigation of geometry dependence on device properties, shortening optimization.
The GFET-S12 has an interdigitated contact geometry. This contact scheme is particularly suitable for gas sensing, as it maximizes current density for a certain bias while conserving much of the active sensing area. The devices are arranged in a grid pattern with different graphene channel widths and electrode gaps, which would help the customer to explore the effect of different contact schemes within the same die. All the devices have the same channel length (1mm), but three different widths (50µm, 100µm and 200µm). The interdigitated contacts have three different gaps (8µm, 15µm and 25µm).
Graphene field-effect transistors (GFETs) have unprecedented sensitivity to the surrounding environment and are an ideal transducer for a variety of sensing applications. Depending on the application, GFETs can be tuned to be sensitive only to the stimulus of interest and have shown breakthrough performance in areas such as graphene device research, quantum transport, gas sensors, chemical sensors and magnetic sensors.