The importance of interdisciplinarity research as a means of addressing some of the most intractable global problems and quality-of-life issues, cannot be overstated. Given this, the Centre’s activities are at the crossroads of engineering, physics, biology and chemistry and these can be split into three broad areas: energy, nanomaterials and fabrication technologies/electronic devices.
Energy Research at EMTERC focuses on innovative ways to generate electrical energy using methods and modalities at the micro and nanoscale. In this regard, there are two main streams of energy research: photovoltaics and power electronics.
Intensive research is currently underway to develop more efficient technologies for low-cost/large area applications in photovoltaic technology. The work is currently divided into two areas; inorganic poly-silicon (poly-Si) solar cells and hybrid organic/inorganic devices.
Inorganic poly-silicon (poly-Si) Solar Cells
Poly-Si thin film cells have higher efficiencies than amorphous silicon (but unfortunately are produced at high temperatures (600-7000C) which make them incompatible with glass/plastic substrates. We have demonstrated for the first time a photovoltaic solar cellwhich uses poly-Si films produced at low temperature (≤4000C) using an in-house, novel growth process with high growth rates and over large areas
Hybrid Organic/Inorganic Devices
Currently the majority of organic photovoltaic devices are made of blends of photoconductive polymers such as poly-hexylthiophene (P3HT) and fullerenes such as PCBM. EMTERC research is looking at adding novel inorganic nanostructures to the blend in order to improve solar cell performance.
There are two main streams in power electronic research. One is focused on novel power semiconductor device structures and materials. And the second is looking at the application of the novel control techniques to minimise energy loses in power electronics systems.
Electron Devices and Materials
Novel power device topologies with improved energy consumption for automotive application (100V), currently commercialised by On Semiconductor. High voltage power devices (1.2kV to 3.3 kV). Electro thermal analysis of the power device performance under high temperature operations. Development of Gallium nitride nanostructures for power device application.
Control Systems and Gate Drive Technologies
Research is looking at the active gate drive based on modified pulse width modulation, which allows control of power devices during a complete switching cycle, thereby minimising energy losses and extending the operational boundary of the power device. Also, development of the intelligent control systems for solid state lightning applications.
With the huge potential of nanomaterials for addressing issues ranging from energy generation to healthcare applications, EMTERC has a vibrant and continually developing stream based on their growth, production and integration into functional devices. These activities are broadly split into two areas (i) materials synthesis (ii) instrumentation development.
We are constantly looking for ways to develop novel methods of producing any functional material on the nanoscale; and by extension, means by which they can be integrated into devices. For example, utilising nanowires as biosensors to enhance significantly the ability to detect early-stage onset of diseases such as Alzheimer’s. With respect to these aims, work within the Centre includes:
- The development of a low-temperature, large-area growth process for nanostructures of zinc oxide
- The utilisation of nanostructures to enhance the efficiency of photovoltaic devices
- The integration of nanomaterials and thin-film deposition processes for multi-purpose material synthesis
- Investigations of amalgamating the unique properties of carbon nanotubes with communication technology
- Nanomaterials for biosensing applications
- Novel synthesis of nanoscale materials to aid in drug delivery
Instrumentation development for the growth of nanomaterials
Whilst using existing technologies and methods for nanomaterial synthesis is an obvious route for their investigation, we are also interested in developing novel instrumentation which could enhance their application in areas such as cheap and flexible electronics:
- Developing inks of semiconducting and metallic nanoparticles for printable electronic devices
- Using mechanical stamping methods for the production of materials and devices
- Developing low-cost, industry-compatible methods for nanomaterial growth
Fabrication Technologies & Electronic Devices
EMTERC has a long history in the investigation and development of electronic devices and their fabrication; and it is with this in mind that the Centre is moving forward into areas that both builds upon this history and which explores novel methods of fabrication and device development.
Emerging Memory Devices
The demand for more efficient and faster memory structures is greater today than ever before. The efficiency of memory structures is measured in terms of storage capacity and the speed of functioning. However, the production cost of such configurations is the natural constraint on how much can be achieved. Organic memory devices (OMDs) provide an ideal solution, as they are inexpensive, and at the same time promising high performance:
- Work carried out within EMTERC on OMDs is at the leading edge of their development and continues to be a vibrant, developing stream of research.
- Investigating the electrical charging mechanisms of gold nanoparticles for use in novel memory applications
Low Temperature Large Area Electronics
A great deal of work has been done within the Centre on low temperature processes for the synthesis of electronic materials for large area and flexible electronic applications, eg thin film transistors (TFTs); and progress continues to be made in this area including:
- The development of an in-house deposition system for thin-film materials
- Extensive work on the fabrication of TFTs incorporating zinc oxide.
- Liquid phase deposition of insulating materials
- Synthesis of organic polymer layers as high performance dielectrics
- Analysis of novel high-k materials
The possibilities within the self-assembly paradigm could lead to the development of virtually any functional device or system. An area that is ideal to exploit using this method is the synthesis of nanomaterials using interdisciplinary research methods.
This is a growing area of interest within the Centre where in addition to materials synthesis, the fundamental electronic, optical and other physical properties are analysed. In this manner - and together with investigating potential methods for organisation of such materials - new areas at the interface of different disciplines can be explored for application in eg nanoelectronics and nanomedicine.