Innovations in UK nanotechnology could spark a technological revolution, says NanoKTN’s director.
1979-1984 BSc in physics, followed by PhD in materials science (solid-state physics), University of Birmingham
Following his degrees, Reader worked as a post-doctoral fellow at Delft Technology University
1984-93 Section head and researcher at Philips Research and Philips Semiconductors, Eindhoven
1992-98 Head of characterisation and failure department, NXP Semiconductors Crolle
1998-2003 Business line manager, Philips Analytical
2003-2004 Senior business-development manager, RINCE
2004-2008 Sales, marketing and technology director, Innos
2008 Appointed director of NanoKTN
Over the past few years there has been a subtle change in the way we see nanotechnology. Ten years ago it was theshiny novelty of the technology world, with some of the claims for its potential barely distinguishable from science fiction. It was mentioned in a dizzying number of research-grant applications and brandished as a buzz word in the advertising of every sector from compact discs to cosmetics.
These days the frenzy has died down and the mentions of nanotechnology have become somewhat less breathless. But, according to the director of NanoKTN, the nanotech knowledge-transfer network, the sector is still very much alive and kicking. Moreover, innovations from the UK could be about to kick off a technological revolution.
’A number of years ago, there was too much hype around all the wonderful things that nanotech could do,’ Alec Reader admitted. ’But what you need to understand is that nanotechnology is a key enabling technology for a variety of sectors.’
“Market demand is starting to pull nanotechnology in certain directions — and that’s the correct way of doing things”
This, he said, is the reason that there is no planned Technology Innovation Centre (TIC) for nanotechnology. ’It goes across so many areas now,’ he explained. ’There are certain markets for example photonics, which is very much enabled by nano-technology; quantum dots are definitely nanotech. Similarly in sensor systems, the key component is frequently a nanoor micro-sensor, but that’s part of a value chain that goes into making the sensor hardware and the software that goes with it. These sectors are the ones that get the TIC, but nanotechnology shouldn’t get one of its own. The technology is joining the mainstream.’
This trend of nanotechnology moving out of dedicated laboratories and into more clearly defined industrial sectors represents an important way in which nanotech research has changed. ’Market demand is starting to pull the technology in certain directions,’ Reader said. ’And that’s the correct way of doing things. There are real market applications that are being found now and it’s not just technology hype: I’d say that’s the biggest change that we’ve seen over the past few years.’
One area that Reader thinks is particularly exciting for nanotechnology and has been earmarked as a prime sector for a TIC is plastic electronics. This sector started out as the preserve of organic chemists investigating the electrical conductance of long-chain compounds that allow electrons to travel along their lengths in ’bonding clouds’, but in recent years, Reader said, it has moved more and more into the domain of physics. The latest trend, he said, is to combine the organic plastics with inorganic semiconductors, which are a product of nanotechnology.
’The mobility of current carriers in organic semiconductors is terrible extremely low,’ he explained. ’If you switch to inorganics, the mobility is two or three orders of magnitude higher and that opens up a whole new range of applications.’
For example, one of the most important sectors for plastic electronics is the displays market; replacing glass displays with plastic considerably reduces the weight of the display and raises the possibility of flexible screens. While organic-based LEDs for the so-called frontplane of the display are now well-developed, the backplane, the integrated circuits and control systems that direct how the LEDs light up to form the display, are proving trickier.
’The problem with plastic electronics that are based purely on semiconductors is that the switching speeds are very low and that means that you’re limited to things such as e-readers where the display doesn’t have to feature much motion,’ Reader said. ’But, if you can make the transistors in the backplane from inorganic semiconductors, the switching speeds are so much faster that they’re going into the video domain and that’s an enormous market.’
“We have to split volume from value”
The key breakthrough is a system that can spray coating to create a nanoscale layer of an organic semiconductor on a polymer film. Developed at Imperial College, the technique involves spraying a chemical precursor of the semiconductor in solution onto a warmed polymer substrate. The heat causes the precursor to decompose on contact, leaving the semiconductor bound to the substrate.
’The semiconductors are based on indium tin oxide or indium zinc oxide,’ Reader said. ’They’re transparent and, if you dope them lightly, a semiconductor. Introduce a dopant precursor into the mix and you control the conductivity.’
Such systems have been known for some time, but the coating has previously been applied by sputtering a complex process requiring very high vacuum. ’It’s not conducive to large-scale manufacturing,’ Reader said. ’But spray-coating is the breakthrough. There are a number of important innovations: the precursor has to be chosen so that it decomposes at the right temperature; the solvent has to produce a fine enough aerosol spray and to evaporate away quickly enough that it doesn’t interfere with the deposition of the film; the substrate has to withstand a certain temperature range.’ The Imperial team is focusing on patent protection for these, he added.
Once the semiconductor film is produced, it can be structured using the same techniques used to transform blank silicon wafers into integrated circuits, by etching using a mask to protect the areas that form the electronic components. ’I think this will make devices that are cheaper and better than those currently available,’ Reader said. ’They’ll be cheap, flexible displays that will be able to show video.’
However, he admits that enabling such complex devices to be made using simple techniques such as spray coating that don’t require complex or expensive equipment to produce could easily lead to this innovation being exploited by low-cost producers in Asia. ’The Imperial team will probably look to license the technology; it’s for them to decide on the business model. But there is the possibility of a high-value step in taking it from a university idea to a real industrial process. I see the point that high-volume production probably wouldn’t be in the UK but, with the right licensing deal, we could capture the high-value part. We have to split volume from value.’
Q&A Big business
How is research and development in nanotechnology changing as the sector matures?
The universities are still doing more blue-skies stuff, which is what they’re paid to do and that’s great. But business and industry are obviously looking at it from a different standpoint from a market standpoint. They’re thinking in terms of how they can use nanotechnology to give them a unique selling point.
Is this a sector where large companies are getting involved?
There are some larger companies, but it’s primarily in the SME space. A lot of SMEs are detecting that there are niche markets where they can start supplying their products and some of them are doing extremely well at it.
Are these generally companies that have formed around some nugget of university research?
A lot of them are in one way or another associated with universities, yes. They’re not all direct spin-outs, though. Some have been associated with a university for a while and they tend to cluster near to the major research universities in the field, because they tend to need certain skills or certain instrumentation, which universities have. It’s a convenience factor, in a way.
Where are these clusters?
A lot of them are focused around the triangle between Oxford, Cambridge and Southampton, and around the M25, within an hour or so from London. Manchester also has a strong area and there’s a cluster in the Northeast associated with Newcastle.
Do these companies need a particular type of support to help them to flourish?
In a lot of areas we’re getting into technology readiness levels five or six, where we need to get the technology into commercialisation to prove it a bit more. That’s where the developers need to write proposals for the Technology Strategy Board, which would be showing an interest at this stage.
Does this mean that it’s in the dreaded technology ’Valley of Death’, where innovations have previously stumbled?
We could be in the Valley of Death, yes. But where there are proposals as exciting as spray-coating inorganic semiconductors, I think this is such an exciting process that there would be a number of companies in the world that would love to get their hands on this and would come forward with the money. There’s a lot of discussion in government about high-value manufacturing and this is high-value stuff.