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Researchers in Norway have created a semiconductor on a graphene substrate—absolutely no silicon in the substrate. From the Sept. 28, 2012 news item on Nanowerk,

Norwegian researchers are the world’s first to develop a method for producing semiconductors from graphene. This finding may revolutionise the technology industry.
The method involves growing semiconductor-nanowires on graphene. To achieve this, researchers “bomb” the graphene surface with gallium atoms and arsenic molecules, thereby creating a network of minute nanowires.
The result is a one-micrometre thick hybrid material which acts as a semiconductor. By comparison, the silicon semiconductors in use today are several hundred times thicker. The semiconductors’ ability to conduct electricity may be affected by temperature, light or the addition of other atoms.

The Research Council of Norway’s Sept.28, 2012 news release, which originated the news item, offers this,

Graphene is the thinnest material known, and at the same time one of the strongest. It consists of a single layer of carbon atoms and is both pliable and transparent. The material conducts electricity and heat very effectively. And perhaps most importantly, it is very inexpensive to produce.

“Given that it’s possible to make semiconductors out of graphene instead of silicon, we can make semiconductor components that are both cheaper and more effective than the ones currently on the market,” explains Helge Weman of the Norwegian University of Science and Technology (NTNU). Dr Weman is behind the breakthrough discovery along with Professor Bjørn-Ove Fimland.

“A material comprising a pliable base that is also transparent opens up a world of opportunities, one we have barely touched the surface of,” says Dr Weman. “This may bring about a revolution in the production of solar cells and LED components. Windows in traditional houses could double as solar panels or a TV screen. Mobile phone screens could be wrapped around the wrist like a watch. In short, the potential is tremendous.”

The researchers have patented this work and founded a startup company, CrayoNano. They provide a video animation of the process,

The narrator mentions epataxial growth and the gallium arsenide nanowires being grown on the graphene substrate. For anyone not familiar with ‘epataxial growth’, I found a definition in another Sept. 28, 2012 news item about graphene research on Nanowerk,

One of the best ways of producing high quality graphene is to grow it epitaxially (in layers) from crystals of silicon carbide. For use in electronic devices, it is important to be able to count the number of graphene layers that are grown, as single and double layers of graphene have different electrical properties.

This research out of the UK is based on using silicon as a substrate and you can find out more (excerpted from the  news item about the National Physical Laboratory’s graphene research on Nanowerk),

Recent National Physical Laboratory research, published in the Journal of Applied Physics (“Identification of epitaxial graphene domains and adsorbed species in ambient conditions using quantified topography measurements” [open access]), looked at different topography approaches of determining graphene thickness and investigated the factors that can influence the accuracy of the results, such as atmospheric water and other adsorbates on the graphene surface.

Getting back to graphene substrates, the Research Council of Norway’s news release provides the reminder that this research is about business,

The researchers will now begin to create prototypes directed towards specific areas of application. They have been in contact with giants in the electronics industry such as Samsung and IBM. “There is tremendous interest in producing semiconductors out of graphene, so it shouldn’t be difficult to find collaborative partners,” Dr Weman adds.

The researchers are hoping to have the new semiconductor hybrid materials on the commercial market in roughly five years.

Dexter Johnson in a Sept. 28, 2012 posting on his Nanoclast blog, which is hosted by the IEEE (Institute of Electrical and Electronics Engineers), provides some business perspective,

Weman notes: “Companies like IBM and Samsung are driving this development in the search for a replacement for silicon in electronics as well as for new applications, such as flexible touch screens for mobile phones. Well, they need not wait any more. Our invention fits perfectly with the production machinery they already have. We make it easy for them to upgrade consumer electronics to a level where design has no limits.”

As magnanimous as Weman’s invitation sounds, one can’t help but think it comes from concern. The prospect of a five-year-development period before a product gets to market might be somewhat worrying for a group of scientists who just launched a new startup. A nice licensing agreement from one of the big electronics companies must look appealing right about now.