From SLAC Today: “Organic Semiconductor” 

January 6, 2012
Diane Rezendes Khirallah

“Simply put, an organic semiconductor is an organic material whose conductivity can be switched on and off at will. This helpful property gives semiconductors a critical role in the on-off switches at the heart of digital devices.

Many associate the word organic with pesticide-free farm products. But in chemistry, organic refers to compounds that contain the element carbon.

Today’s most common semiconductor is silicon, which, being its own element, contains no carbon. By controlling conditions such as the percentage and type of impurities in the material and varying the amount of electrical current and the intensity of light – whether visible, infrared or X-ray – scientists can control how the semiconductor behaves.

But while silicon crystals are durable and allow electrical current to flow rapidly, they are also rigid and expensive to produce, making large-scale implementation cost-prohibitive (for example, in a large-scale solar array).

In contrast, organic semiconductors – typically plastics and polymers that can be produced in sheets as little as one molecule thick – offer an inexpensive, lightweight, more flexible option. But they don’t yet conduct electricity as efficiently as silicon or operate for as long, which has limited their commercial use.”

The full article is here.

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Magnified view of organic semiconductor crystals recently grown by Stanford chemical engineers, who studied their structural properties at SLAC’s Stanford Synchrotron Radiation Lightsource.Image courtesy Gaurav Giri, Chemical Engineering, Stanford University

Now, here is an example of how this research is being applied today-

The Clean Energy Project (CEP2), at Harvard University is doing work in collaboration with research teams at SLAC.

CEP2 is a project in Public Distributed Computing under the World Community Grid (WCG) arm of IBM’s Smarter Planet initiative. You can make a contribution to this project with the idle CPU cycles on your computer(s). WCG projects run on a small piece of software from UC Berkeley, called BOINC - the Berkeley Open Infrastructure for Network Computing. Just visit the WCG web site or the BOINC web site, download and install the BOINC software. Visit the WCG web site to attach to the project. While you are at WCG, take a look at the other very worthwhile projects and attach to as many as you wish.

Also, at the BOINC web site, you will find a whole host of other projects in the Physical Sciences, Astronomy and Cosmology, Mathematics and other areas. Again, you can attach to as many projects as you like.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science. i1