The National Physical Laboratory (NPL), the UK's National Measurement Institute, is developing equipment and techniques to support the growing use of organic electronics. The market for organic, or plastic, electronics is expected to be worth £15 billion by 2015 (IDTechEx), and NPL is seeking to ensure the infrastructure is in place to allow businesses to achieve commercial success in this emerging area.
The technology has huge potential in such areas as solar energy, smart packaging, medical diagnostics, displays and lighting, and testing and characterisation of organic electronic devices is becoming increasingly important.
NPL's organic electronics team aims to address these by understanding the fundamental science of organic electronics. Specifically, the team is focusing on two main areas - photovoltaics and printing deposition of organic materials.
To date, the group has:
- Set-up an ultra-high vacuum atomic force microscopy system, enabling precise topographic and electrical measurements on organic films.
- Developed a strategic collaboration with Imperial College London, including a joint postdoctoral research fellow in Excitonic Photovoltaics. X-ray photoelectron spectroscopy has revealed the vertical composition profile of blended organic semiconductor thin-films.
- Determined the structure of organic semiconductor layers for thin-film transistors using molecular resolution atomic force microscopy and X-ray diffraction.
- Developed a wettability model based on chemical mapping, which effectively describes experimental surface energy data, as determined by micro-contact angle measurement of printing substrates.
The next phase of the project is looking to set up a specialized facility for use in fabricating thin-films and devices; support solar cell efficiency improvements through spatial mapping of the work function of photovoltaic blends using imaging ultraviolet photoelectron spectroscopy; and develop photoconductive atomic force microscopy methods for photocurrent response on the nanoscale to further support efficiency gains in solar cell technology.
NPL's metrology expertise has played a role in several Technology Strategy Board-backed projects over the past few years, working with partners from industry and academia.
"In all these projects, our role has been to assist in the accurate measurement and characterization of electronic and chemical properties at the sub-micron level, and often this has included devising novel techniques for making such measurements," said Craig Murphy, project lead.
NPL is also becoming involved in supporting the development of standards for measurement methods related to organic electronics.