Abstract: A method for manufacturing a biological field-effect transistor (BioFET) is disclosed. In some implementations, the method may include preparing a carbonaceous dispersion by adding a three-dimensional (3D) graphene into a solvent; depositing the carbonaceous dispersion onto a p-type silicon wafer; spin-coating a positive photoresist over the carbonaceous dispersion; forming source and drain terminals on the p-type silicon wafer, the source and drain terminals in contact with the 3D graphene of the carbonaceous dispersion; removing residual photoresist from the carbonaceous dispersion by placing the p-type silicon wafer in 1-methyl-2-pyrrolidone (NMP); and biofunctionalizing the carbonaceous dispersion with a molecular recognition element configured to alter one or more electrical properties of the Bio-FET in response to exposure of the molecular recognition element to the analyte.

Abstract: A biological field-effect transistor (BioFET) includes source and drain regions formed in a substrate, an insulating layer disposed on a surface of the substrate, a gate disposed on the insulating layer and extending between the source and drain regions, a well region containing an electrolyte solution configured to retain an analyte, a three-dimensional (3D) graphene layer forming a channel region in the substrate, and a passivation layer. The graphene layer is biofunctionalized with a molecular recognition element configured to alter one or more electrical properties of the 3D graphene layer in response to exposure of the molecular recognition element to the analyte. The passivation layer is configured to prevent the electrolyte solution from contacting the source and drain. In some aspects, the 3D graphene layer is produced from carbon-containing inks. In other aspects, the 3D graphene layer includes a convoluted 3D structure configured to prevent graphene restacking.

Abstract: Methods for detecting analytes using a biological field-effect transistor (BioFET) are disclosed. In some implementations, the method includes exposing a three-dimensional (3D) graphene layer biofunctionalized with a biological recognition element to a target analyte, providing a well region containing an electrolyte solution configured to retain the target analyte, allowing the target analyte to disperse throughout the electrolyte solution and bind with the biological recognition element, detecting a change in electrical properties of the 3D graphene layer in response to the target analyte binding with the biological recognition element, determining a presence of the target analyte based on the change in electrical properties, and outputting an indication of the determined presence of the target analyte. In some aspects, the 3D graphene layer may operate as a channel for the BioFET.

Abstract: A method for manufacturing a biological field-effect transistor (BioFET) is disclosed. In some implementations, the method may include preparing a carbonaceous dispersion by adding a three-dimensional (3D) graphene into a solvent; depositing the carbonaceous dispersion onto a p-type silicon wafer; spin-coating a positive photoresist over the carbonaceous dispersion; forming source and drain terminals on the p-type silicon wafer, the source and drain terminals in contact with the 3D graphene of the carbonaceous dispersion; removing residual photoresist from the carbonaceous dispersion by placing the p-type silicon wafer in 1-methyl-2-pyrrolidone (NMP); and biofunctionalizing the carbonaceous dispersion with a molecular recognition element configured to alter one or more electrical properties of the Bio-FET in response to exposure of the molecular recognition element to the analyte.