Big Commitment to Research on Tiny Things
In early November Halmstad University received a grant of about SEK 3 million from the Swedish Research Council for a research project in nanotechnology. The research director is Håkan Pettersson, professor of physics at the University. Together with Professor Lars Samuelson, Lund University, he is also coordinating a recently funded framework program in nanotechnology worth SEK 8 million, also financed by the Swedish Research Council.
"These two projects considerably bolster our research in nanotechnology and enable us to invest in new doctoral studentships and third-cycle education," says Håkan Pettersson.
Research in nanotechnology has been pursued for a long time at the research environment EIS at Halmstad University. Nanotechnology is about creating more efficient components and products by exploiting properties of new materials created when the size is shrunk to a couple of score nanometers.
"A nanometer is one billionth of a meter. It's hard to understand how small a nanometer actually is. One comparison is that the thickness of a regular piece of paper is a hundred thousand nanometers," explains Håkan Pettersson.
"An exciting example of nanotechnology is so-called nanotubes that can serve as a basis for entirely new types of optical components for the electronics industry of the future. Rydberg Laboratory at the University is a major resource in studying the properties of these components. It's a modern laboratory with advanced equipment for experimental activities in science and closely related engineering fields," says Håkan Pettersson.
What the two nanotechnology projects have in common is that they are about producing new types of optical components — such as light diodes and sensors for heat radiation — by "cultivating" optically active nanostructures directly on an inexpensive silicon plate — a chip.
Today's method complicated and expensive Today such components are made separately and then integrated with silicon, which is both complicated and expensive. One major obstacle is that silicon, which is by far the most commonly used material for electronics, cannot be applied in the production of light diodes, for example. Instead other more complicated materials like gallium arsenide or gallium nitride have to be used.
"These are expensive materials that normally cannot be directly combined with silicon. Amazingly, it turns out that if you simply shrink the light diodes or sensors to nano size, making their 'footprint' small enough, mother nature allows them to be directly 'cultivated' on a silicon chip," says Håkan Pettersson.
Million upon millions of nanotubes One example of such tiny structures are so-called nanotubes, which can be described as extremely thin fibers. Among other things, nanotubes have the characteristic that they can be produced by the millions on a silicon surface with the use of a relatively simple technology. The production process is called self-organising and can be defined simply as spraying tiny gold particles onto the silicon surface and then placing the silicon plate in a hot over with gases containing the elements to be included in the finished tubes. A chemical reaction takes place in the border layer between the gold particles and the silicon, which prompts a spontaneous growth of tubes.
!In our projects the challenge is to produce new types of nanotube-based light diodes and sensors directly on silicon for optical communication, or heat-sensing cameras to detect criminals sneaking around in the dark, an incipient skin-cancer tumor, or a planet orbiting a remote star," says Håkan Pettersson.
Potential for more doctoral students The research grants from the Swedish Research Council will mainly be used to finance new doctoral students. Two doctoral students have already been employed at the University and a further doctoral studentship will be advertised soon. Besides Halmstad University and Lund University, Harvard University in the US and the Swedish research institute Acreo will take part in the projects.
Text: LENA LUNDÉN