Efforts to commercialize electronic devices based on graphene have reached significant milestones through the support of the European Union’s 2D-Experimental Pilot Line (2D-EPL) project. Despite over 20 years since graphene's first isolation, the technology for producing graphene devices at scale has struggled to gain traction. The 2D-EPL project, funded by the European Commission with €20 million from October 2020 to September 2024, is set against this backdrop, aiming to establish the first European pilot line for electronic and optoelectronic devices derived from graphene and other two-dimensional materials.
Recently, researchers reported the outcomes from two pivotal multi-project wafer (MPW) runs—the first completed at the end of 2022 and the third at the end of 2023. These runs, which serve as platforms enabling various stakeholders, from universities to small enterprises, to have graphene devices fabricated, were instrumental for the continued advancement of wafer-scale graphene technology.
During these MPW runs, numerous test devices were manufactured to evaluate device quality and its variability. Raman spectroscopy analyses confirmed minimal structural changes to the graphene, underscoring the efficacy of the fabrication processes involved. More critically, electrical measurements conducted on different device types validated the specifications laid out beforehand.
The project's roots are grounded deeply within the Graphene Flagship initiative, which sought to conquer the hurdles standing between scientific potential and commercial applicability of graphene technology. The 2D-EPL project uniquely addresses the discrepancies between the availability of production-ready tools and processes necessary for creating devices and the immediate needs of customers seeking functional devices.
The structure of the MPW runs mirrored the demand from diverse customer bases. The first run largely focused on producing graphene-based sensors, whereas the third run shifted its focus toward graphene electronics. This diversification highlighted the adaptability of the project to various applications and market demands. Design rules and fabrication workflows were established to enable customers to specify their desired outcomes; this flexibility, lauded during the first run, was adjusted for the third run to mitigate process-related challenges faced previously.
Remarkably, the results achieved marked notable success: MPW run 1 saw 94% yield with 122 devices functioning out of 130, and MPW run 3 followed closely with 87% yield from 148 devices out of 170. The quality of the devices surpassed initial specifications, illuminating the project’s ability to meet and exceed expectations.
Despite the progress acknowledged, the project was not without its challenges, particularly related to the technical and procedural components of the fabrication process. Notable difficulties included loose definitions of design protocols and resist residues characteristic of graphene integration—a problem of increasing significance as biosensing applications were targeted.
Lessons learned from the first MPW run directly informed the methodology of the third run. By tightening the design protocols and adapting fabrication techniques accordingly, the project demonstrated its capacity for iterative improvement and responsiveness to stakeholder needs.
The 2D-EPL project encapsulates the commitments of the European research initiatives aimed at bringing graphene technology closer to commercialization. With both MPW run 1 and run 3 culminating successfully, the path forward appears more defined, highlighting the project as both a commercial opportunity and as proof of the substantial advances possible within the field of graphene electronics.