Technology requirements for future IC systems include low power computing and communication, sensing capabilities and energy harvesting. These will unlikely be met with silicon technology alone. The InteGraDe project investigates graphene as a potential alternative technology and contributes to bridging the “valley of death” in innovation in these fields. In detail, the proposal focuses on the experimental exploration of novel (opto-) electronic devices and systems based on graphene. Strong emphasis is put on integration, defined as an interdisciplinary approach combining graphene material science, graphene process technology and manufacturing, device engineering and -physics as well as system design. This kind of approach is urgently needed in order to open new horizons for graphene, because it enables a transition from fascinating science to a realistic demonstration of graphene’s application potential in electronics and optoelectronics. The first requirement for the applicability of graphene in ICT is a scalable graphene fabrication technology that can be co-integrated with silicon. The second aspect investigated is the intricate relationship between process technology and graphene device performance. The third aspect to be considered when discussing integration is how devices can be integrated in existing or future systems, including questions of circuit design. Will graphene systems outperform existing solutions and thus replace them? Will new functionalities emerge and generate novel applications? Hence, the key objectives of this project are: 1) a scalable, CMOS compatible large area fabrication technology for graphene and graphene devices, 2) demonstration and assessment of performance advantages and new functionalities of electronic graphene devices, 3) demonstration of graphene-based optoelectronic devices integrated with silicon technology and 4) experimental exploration of the performance potential of graphene-based integrated systems.
The research carried out in InteGraDe has contributed to several breakthroughs. Results on electronic devices includes the first experimental demonstration of graphene hot electron transistors, a compact model for graphene field effect transistors and its implementation in an industrial environment and a first systematic comparison of reliability aspects in graphene transistors with silicon technology. Research on optoelectronics has resulted in several hybrid device concepts, utilizing existing silicon technologies. Several challenging shortcomings of graphene technology have been identified and pointed out to the community, such as electrical contacts, dielectric interfaces and contamination issues in CVD grown graphene. The InteGraDe project has further stimulated and enabled research into nanoelectromechanical sensors and printable electronics based on graphene: The InteGraDe team has demonstrated integrated pressure sensors with highest sensitivity and a new laser annealing technology for solution-based graphene thin films.