Electromagnetic characterisation of materials for industrial applications up to microwave frequencies

Advances in electronics technology lie behind all developments in ICT and there is a world-wide demand for ever-faster electronics. To cope with the increasingly-high operational speeds of modern electronic equipment, new measurement techniques are required to assess the electromagnetic materials used in the fastest applications – at microwave frequencies up to 80 GHz.

This project developed a suite of traceable metrological tools for characterising passive (dielectric and magnetic) and active ‘functional’ electromagnetic materials across the spectrum from low frequencies of 100 kHz through radio frequencies (RF) and up to microwave frequencies of 80 GHz. The project developed or improved the performance of a range of measurement instrumentation, for example:

• Two types of nanoscale near-field scanning microwave microscopes (NSMMs) were developed – one with a spatial resolution of tens of nanometres and one with tens of micrometres – to determine the dielectric, capacitive and conductive properties of materials at small scales across a material surface. Understanding these properties at this scale enables the selection of materials with specific features for electronics and other applications.
• The understanding of microscale NSMMs was significantly improved – it is now possible to make traceable measurements of complex permittivity at microwave frequencies.
• Coplanar waveguide (CPW) and split cylinder (SC) techniques were developed to provide traceable measurements on substrate materials and on functional thin films mounted on substrates. These are needed to assess the quality and performance of traditional silicon substrates at high frequencies during the manufacturing process and the performance of thin films.

The new facilities are available at European measurement institutes to support the development of electronic materials, production equipment and devices. An instrument manufacturer is using calibration artefacts and knowledge developed in the project to expand the range of electronic material properties that can be measured and ensure its NSMMs can meet industrial requirements. A company that designs and manufactures RF and microwave components for the mobile telecommunications industry used the tools to better understand and improve the performance of the dielectric resonators used in communications base stations.