| Autor: |
Ali MM; Centre for NanoHealth, College of Engineering, Swansea University, Swansea SA2 8PP, UK., Mitchell JJ; Centre for NanoHealth, College of Engineering, Swansea University, Swansea SA2 8PP, UK., Burwell G; Department of Physics, College of Science, Swansea University, Swansea SA2 8PP, UK., Rejnhard K; Department of Physics, College of Science, Swansea University, Swansea SA2 8PP, UK., Jenkins CA; School of Medicine, Swansea University, Swansea SA2 8PP, UK., Daghigh Ahmadi E; Centre for NanoHealth, College of Engineering, Swansea University, Swansea SA2 8PP, UK., Sharma S; Faculty of Science and Engineering, Bay Campus, Swansea University, Swansea SA1 8EN, UK., Guy OJ; Centre for NanoHealth, College of Engineering, Swansea University, Swansea SA2 8PP, UK.; Department of Chemistry, College of Science, Swansea University, Swansea SA2 8PP, UK. |
| Abstrakt: |
Graphene-based point-of-care (PoC) and chemical sensors can be fabricated using photolithographic processes at wafer-scale. However, these approaches are known to leave polymer residues on the graphene surface, which are difficult to remove completely. In addition, graphene growth and transfer processes can introduce defects into the graphene layer. Both defects and resist contamination can affect the homogeneity of graphene-based PoC sensors, leading to inconsistent device performance and unreliable sensing. Sensor reliability is also affected by the harsh chemical environments used for chemical functionalisation of graphene PoC sensors, which can degrade parts of the sensor device. Therefore, a reliable, wafer-scale method of passivation, which isolates the graphene from the rest of the device, protecting the less robust device features from any aggressive chemicals, must be devised. This work covers the application of molecular vapour deposition technology to create a dielectric passivation film that protects graphene-based biosensing devices from harsh chemicals. We utilise a previously reported "healing effect" of Al 2 O 3 on graphene to reduce photoresist residue from the graphene surface and reduce the prevalence of graphene defects to improve graphene device homogeneity. The improvement in device consistency allows for more reliable, homogeneous graphene devices, that can be fabricated at wafer-scale for sensing and biosensing applications. |
