Year/Course: 2011-2012, Lent 2012

Contacts: Dr Andrew Flewitt, CAPE
Mentors: Marc Bax, Bob Pettigrew

There are many applications where several physical attributes such as light levels, temperature and humidity need to be measured, and others which need gases to be detected. Currently these type of measurements are carried out on separate sensors, working in very different ways.

Dr Flewitt is working as part of an EPSRC-funded joint project between Cambridge, Manchester and Bolton Universities. The research team has developed a new sensor which can measure two or more of these attributes simultaneously. The sensor is based on piezo-electric methods, using a Zinc Oxide membrane which expands and contracts in response to the application of an electrical voltage. As the electrical voltage changes, resonant frequencies can be set up. These are measured in GHz, and are very sensitive to surface changes.

The advantage of this approach is that the whole set of sensors will be on a common platform, greatly reducing the complexity of the total system. The technology is very flexible, small in size (less than 1cm2) and low cost, and could be used in a wide range of applications, from monitoring physical environments to detecting particular microbes or molecules. Clearly a disposable device for detecting microbes would have very different requirements from a sensor inside a car which would need to last for the car’s lifetime.

The researchers have already successfully measured a range of attributes, including temperature and humidity, and have detected several different gases, including ethanol and DEET (the active ingredient in mosquito sprays). However, for the next stage of their work they need to know where the sensor might be used in practice, so that they can focus their efforts on developing something with real commercial and practical value.

The question for the i-Team is to find out where a multiplex sensor on a common platform would be useful, what performance ranges would be needed, and which market offers the most exciting opportunity for the inventors to pursue.