Silicon photonics is the manipulation of light (photons) in silicon-based substrates, analogous to electronics, which is the manipulation of electrons. The development cycle of a silicon photonics device consists of three stages: design, fabrication, and characterisation. Whilst design and characterisation can readily be done by research groups around the country, the fabrication of silicon photonics devices, circuits and systems requires large scale investments and capital equipment such as cleanrooms, lithography, etching equipment etc. Based at the Universities of Southampton and Glasgow, CORNERSTONE 2.5 will provide world-leading fabrication capability to silicon photonics researchers and the wider science community. Whilst silicon photonics is the focus of CORNERSTONE 2.5, it will also support other technologies that utilise similar fabrication processes, such as MEMS or microfluidics, and the integration of light sources with silicon photonics integrated circuits, as well as supporting any research area that requires high-resolution lithography. The new specialised capabilities available to researchers to support emerging applications in silicon photonics are: 1) quantum photonics based on silicon-on-insulator (SOI) wafers; 2) programmable photonics; 3) all-silicon photodetection; 4) high efficiency grating couplers for low energy, power sensitive systems; 5) enhanced sensing platforms; and 6) light source integration to the silicon nitride platform. Access will be facilitated via a multi-project-wafer (MPW) mechanism whereby multiple users' designs will be fabricated in parallel on the same wafer. This is enabled by the 8" wafer-scale processing capability centred around a deep-UV projection lithography scanner installed at the University of Southampton. The value of CORNERSTONE 2.5 to researchers who wish to use it is enhanced by a network of supporting companies, each providing significant expertise and added value to users. Supporting companies include process-design-kit (PDK) software specialists (Luceda Photonics), reticle suppliers (Compugraphics, Photronics), packaging facilities (Tyndall National Institute, Bay Photonics, Alter Technologies), a mass production silicon photonics foundry (CompoundTek), an epitaxy partner for germanium-on-silicon growth (IQE), fabrication processing support (Oxford Instruments), an MPW broker (EUROPRACTICE), a III-V die supplier (Sivers Semiconductors) and promotion and outreach partners (Photonics Leadership Group, EPIC, CSA Catapult, CPI, Anchored In). Access to the new capabilities will be free-of-charge to UK academics in months 13-18 of the project, and 75% subsidised by the grant in months 19-24. During the 2-year project, we will also canvas UK demand for the capability to continue to operate as an EPSRC National Research Facility, and if so, to establish a Statement of Need.

Southampton and Glasgow Universities currently contribute to a project entitled CORNERSTONE which has established a new Silicon Photonics fabrication capability, based on the Silicon-On-Insulator (SOI) platform, for academic researchers in the UK. The project is due to end in December 2019, after which time the CORNERSTONE fabrication capability will be self-sustaining, with users paying for the service. Based upon demand from the UK's premier photonics researchers, this proposal seeks funding to extend the capability that is offered to UK researchers beyond the current SOI platforms, to include emerging Silicon Photonics platforms, together with capabilities facilitating integration of photonic circuits with electronics, lasers and detectors. These emerging platforms enable a multitude of new applications that have emerged over the past several years, some of which are not suitable for the SOI platform, and some of which complement the SOI platform by serving applications at other wavelengths. Southampton, and Glasgow universities will work together to bring the new platforms to a state of readiness to deliver the new functionality via a multi-project-wafer (MPW) mechanism to satisfy significantly increasing demand, and deliver them to UK academic users free of charge (to the user) for the final six months of the project, in order to establish credibility. This will encourage wider usage of world class equipment within the UK, in line with EPSRC policy. We seek funding for 3 PDRAs and 2 technicians across the 2 institutions, over a 2 year period, to facilitate access to a very significant inventory of equipment at these 2 universities, including access to UK's only deep-UV projection lithography capability. During this 2 year period, we will canvas UK demand for the capability to continue to operate as an EPSRC National Research Facility, and if so, to establish a statement of need. We currently have 50 partners/users providing in-kind support to a value of to £1,705,000 and cash to the value of £173,450.

Graphene is ideal for opto-electronics due to its high carrier mobility at room temperature, electrically tuneable optical conductivity, and wavelength independent absorption. Graphene has opened a floodgate for many layered materials (LMs). For a given LM, the range of properties and applications can be tuned by varying the number of layers and their relative orientation. LM heterostructures (LMHs) with tailored properties can be created by stacking different layers. The number of bulk materials that can be exfoliated runs in the thousands, but few have been studied to date. The layered materials research foundry (LMRF) will develop a fully integrated LM-Silicon Photonics platform, serving 5G, 6G and quantum communications, facilitating new design concepts that unlock new performance levels. Graphene and the other non-graphene LMs are at two different stages of development. Graphene is more mature, and can now target functionalities beyond the state of the art in technologically relevant devices. In (opto-)electronics, photonics and sensors, graphene-based systems have already demonstrated extraordinary performance, with reduced power consumption, or photodetectors (PDs) with hyperspectral range for applications such as autonomous driving, where fast data exchange is a critical requisite for safe operation. Applications in light detection and ranging, security, ultrasensitive physical and chemical sensors for industrial, environmental and medical technologies are beginning to emerge and offer great promise. These technologies must be developed to achieve full industrial impact. The other non-graphene LMs are also at the centre of an ever increasing research effort as a new platform for quantum technology. They have already shown their potential, ranging from scalable components, such as quantum light sources, photon detectors and nanoscale sensors, to enabling new materials discovery within the broader field of quantum simulations. The challenge is understanding and tailoring the excitonic properties and the nature of the single photon emission process, as well as to make working integrated devices. Quantum emitters in LMs hold potential in terms of scalability, miniaturisation, integration with other systems and an extra quantum degree of freedom: the valley pseudospin. A major challenge is to go beyond lab demonstrators and show that LMs can achieve technological potential. The LMRF will accelerate this by enabling users to fabricate their devices in a scalable manner, with comparable technology to large-scale manufacturing foundries. This scalability is essential for LMs to become a disruptive technology. The vision is to combine the best of Silicon Photonics with LM-based optoelectronics, addressing key drawbacks of current platforms. ICT systems are the fastest growing consumers of electricity worldwide. Due to limitations set by current CMOS technology, energy efficiency reaches fundamental limits. LM-based optoelectronics builds on the optical/electronic integration ability of Silicon Photonics, which benefits product costs, but with modulator designs simpler than conventional Silicon Photonics at high data rates, giving lower power consumption.