We will solve the manufacturing issues in producing integrated sensor arrays and control electronics at scale (including large area substrates) and demonstrate this via 2 different application areas. These have different device technology and are at different stages of maturity, so lessons learnt from the more mature can benefit the other. This GC also underpins the EPSRC Connected and Resilient Nation priorities by addressing the need for low power, low cost, high sensitivity ubiquitous sensing and imaging.
Semiconductor sensors (electronic, magnetic and optical) are indispensable components in the future Internet of Things (IoT), robotics, industrial non-destructive testing (NDT) of materials and high resolution spectroscopy and imaging. NDT underpins engineering and associated downstream industries in complex in-situ, in-service monitoring (Oil & Gas, Aerospace, Pipe and Rail manufacturing and use and Nuclear Generation), with consequent scientific, commercial and societal benefits. CS will radically improve sensitivity, allow real time data analysis and facilitate disruptive new approaches using e.g. sensor arrays. They will allow inspection in hazardous and remote applications such as deep water oil exploration and in the nuclear industry. According to MarketsandMarkets, the NDT testing equipment market was worth $3.77bn in 2014 and predicted to reach $6.88bn by 2020 (growth of 9% pa). Strikingly, the biggest challenge facing this industry is the lack of qualified technicians to understand and use NDT systems. To offset this the introduction of lightweight, low power use, cost effective and above all ease of use (measurement and interpretation) are key features that our partners require to integrate into their instruments.
This vision will be delivered using new modalities in CS devices and circuits for applications where the superior properties of CS (high speed operation, high sensitivity, radiation hardness, infra-red imaging and high temperature operation) are immediately critical.
The low cost manufacturing of these sensors will rely both on the use of large GaAs substrates (to 150mm), for lower cost processing, and the medium scale integration of the sensors needed for deployments in a number of harsh environments but also with hybrid or grown directly on Si substrates where operational conditions are more benign. We have already produced all GaAs analogue quantum well Hall Effect (QWHE) circuits for magnetic sensing with superior sensitivity, bandwidth and operating temperature as shown in the figure below, which now require full integration.
In terms of optical sensors we will form a disruptive technology, far exceeding the performance of bolometers and the current state of the art Mercury Cadmium Telluride (MCT) and GaAs/GaAlAs QWIP (Quantum Well Infrared Photodetector) technologies that are severely limited by uniformity problems and poor quantum efficiency (~10%) respectively. InAs/GaSb Type II Strained Layer Superlattice (SLS) will be pursued as the superior candidate for the next generation of high performance infrared imaging systems (high operating temperature, multispectrality, large focal plane array and, far infrared domain operation).
Working with our partners we will establish the fundamental limitations of both magnetic and optical technology, i.e. spatial and contrast resolution, image capture and processing rates.
GC2 Programme and Methodology