Recently in MRS Fall 2008 Category
Happy holidays and see you again next year. For dates, check out the MRS website.
Walking up and down the aisles, I must have counted well over a dozen scanning probe microscope (SPM) makers from across the globe with products to promote. What started as a "home built" instrument has matured into a plug-and-play piece of product design.
At the exhibit, most of the SPMs on show are more than just display items. More and more firms are encouraging attendees to turn up with a sample for imaging, which makes the MRS fall meeting a great opportunity to find out which SPM works best for you.
When it comes to flattening vertically aligned carbon nanotubes (CNTs), the diameter of the "rolling pin" is critical. As Sameh Tawfick explained in his talk yesterday afternoon, if the pin is too large then it buckles the CNTs and destroys the alignment. If the roller is too small then it gets caught up in the forest of nanotubes and leads to patchy densification.
The team's goal is to prepare a well defined sheet of the material that can then be used for contact printing structures such as interconnects. And who would be interested in this? Well, Intel for one, if the author affiliations provide a clue.
Some more facts and figures just in - Tawfick revealed that a 0.6 mm pin is ideal for a 1 mm high CNT forest. Once flattened, the structures are dipped in solvent to further densify the material before transfer printing.
Related story -
Inventors roll out nanotube paper
Show floor area 600 has been dubbed the "Nano" aisle at this year's exhibit. Attendees taking a stroll in this direction are treated to super plush carpeting and can stop by at the open seminar area. Here, industry experts take turns to give advice on a range of nano-related topics such as image analysis, AFM probe selection and new tools for extreme environments, all in easy-to-handle 25 minute slots. The snappy tag line for the presentations, which run from Tuesday - Thursday, is "No selling - just information on how does it work and can I make use of it?"
Room 302 was the venue for Zhong Lin Wang's explanation of nanopiezotronics - the use of piezoelectric nanowires in electronics.
Wang showed the audience how semiconducting nanowires can be configured to form a piezoelectric diode, a humidity sensor, a piezoelectric transistor and a nanogenerator. What's more, if you make the nanowire out of CdS then the nanogenerator becomes light sensitive, providing power only when illuminated.
Related stories -
Sitting in on symposium T, it was time to find out more about mobile energy - specifically, batteries that can be bent.
Pritesh Hiralal from Cambridge University, UK, is part of a team working on all-solid thin-film batteries for portable applications, or as he phrased it - flexible batteries for flexible electronics.
Hiralal's approach is to redesign a standard zinc-carbon cell layer-by-layer and the latest prototype features a combination of electrospun carbon fibre cloth, single-walled carbon nanotubes and ceramic nanoparticles.
There's more work to be done, but the initial results are encouraging and show that the flexible cell is able to withstand several bending cycles.
Howard Wang of Binghampton University, US, gave an update on the performance of sintered metal nanoparticles. The team is pulling together technology to realize high-performance roll-to-roll electronics and has been successful in using inkjet-printed metal nanoparticles to interconnect devices on the flexible and often temperature sensitive substrates.
Wang sources his particles from NanoMas - a supplier of silver nanoparticles measuring 2 nm in diameter. The reduction in melting point with particle size means that the researchers can run their sintering process at just 100 degC, which opens the door to a wide range of roll-to-roll compatible films.
Related stories on nanotechweb.org -
Electrical sintering joins up nanoparticles
Laser sintering strikes gold with nanoparticle ink