This is part of a double webinar featuring Prof. Patrick Parkinson
The non-planar nature of free-standing III–V nanowires creates new opportunities for electronic and optoelectronic device architectures, but also necessitates new strategies for nanowire growth, characterisation and integration. This presentation will discuss these strategies. The growth parameters for catalyst-free and silane-assisted III–nitride nanowire growth by metalorganic vapour phase epitaxy will be discussed. Surface modifications and passivation, achieved either during growth or post-growth, are also necessary for achieving reproducible device performance. We will present the development of a multiplexer chip capable of addressing single-nanowire transistors in arrays. Nanowires, deterministically positioned on the multiplexer by transfer-printing, exhibited reproducible electrical behaviour and high device yield. The multiplexer’s ability to operate from room temperature down to milliKelvin temperatures enables the study of quantum phenomena in multiple and interconnected nanowire devices. A promising route towards flexible electronics involves embedding nanowires in a transparent polymer host matrix. By judicious choice of polymer type and deposition conditions, the encapsulated nanowire array preserves the as-grown orientation of the nanowires and can be removed from the rigid growth substrate, creating a flexible and robust device while permitting re-use of the substrate for subsequent growths. This process technique has been used to create flexible terahertz modulator devices based on arrays of aligned GaAs nanowires.
About the speaker
Hannah Joyce is a TMOS Partner Investigator and Professor in low-dimensional electronics at the University of Cambridge. In 2013, Hannah joined the Department of Engineering at the University of Cambridge, after completing her PhD at the Australian National University and after completing her postdoc at the University of Oxford. In Cambridge she leads a research group focussing on the development of novel nanomaterials for applications in photonics and electronics. Her interests span the growth of novel low-dimensional semiconductor materials, the development of terahertz spectroscopy for contact-free characterisation of nanomaterials, and the development of new nanomaterial-based devices such as photovoltaics, photodetectors and terahertz photonic modulators.