Innovation Seminar Series - Porous nitrides: Adding value by taking material away?

Speaker: Professor Rachel Oliver, Department of Materials Science and Metallurgy, University of Cambridge

orous semiconducting nitrides are effectively a new class of semiconducting material, with properties distinct from the monolithic nitride layers from which devices from light emitting diodes (LEDs) to high electron mobility transistors are increasingly made. The introduction of porosity provides new opportunities to engineer a range of properties including refractive index, thermal and electrical conductivity, stiffness and piezoelectricity.

A novel etching process has been developed, which allows complex subsurface porous multilayers to be straightforwardly fabricated, but leaves the top surface of the material almost unaltered and suitable for further epitaxy.  Etching proceeding vertically from the top surface through channels formed at naturally-occurring defects in the crystal structure of GaN. This new defect-based etching process provides great flexibility to create novel device designs, enabling improvements to light extraction efficiency in LEDs for solid state lighting and new approaches to strain management in LEDs for microdisplays.  These discoveries have formed the basis of a spinout company, Poro Technologies Ltd, which has recently announced a new technology which allows full-colour microdisplays to be created from a single wafer of nitride material, a transformative approach in terms of reduction in manufacturing complexity.

Registration: https://www.eventbrite.co.uk/e/porous-nitrides-adding-value-by-taking-material-away-tickets-795190655657

Professor Rachel Oliver is a materials scientist, inventor and spinout founder who also campaigns for equity in science and engineering research.  Her passion for understanding and engineering the small-scale structure of materials to enable new technologies was recognised in 2021 by the award of a Fellowship of the Royal Academy of Engineering and her selection as an IEEE Photonics Society Distinguished Lecturer.  She currently holds a prestigious Chair in Emerging Technologies from the Royal Academy of Engineering.