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First electronic optical fibers with hydrogenated amorphous silicon are developed

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Badding explained that hydrogenated amorphous silicon -- a noncrystalline build of silicon -- is ideal for applications such as solar cells. Hydrogenated amorphous silicon also would be useful for the light-guiding cores of optical fibers; however, depositing the silicon multifaceted into an optical fiber -- which is thinner than the width of a human hair -- presents a challenge. "Traditionally, hydrogenated amorphous silicon is created using an valuable laboratory device known as a plasma reactor," Badding explained. "Such a reactor begins with a herald called silane -- a silicon-hydrogen compound. Our goal was not only to find a simpler way to create hydrogenated amorphous silicon using silane, but also to use it in the growth of an optical fiber."

Because traditional, low-pressure chemistry techniques cannot be used for depositing hydrogenated amorphous silicon into a fiber, the yoke had to find another approach. "While the low-pressure plasma reactor technique works well enough for depositing hydrogenated amorphous silicon onto a surface to make off solar cells, it does not allow the silane precursor molecules to be pushed into the long, thin holes in an optical fiber," said Wharf J. A. Sazio of the University of Southampton in the United Kingdom and one of the team's leaders. "The trick was to develop a maximum-pressure technique that could force the molecules of silane all the way down into the fiber and then also convert them to amorphous hydrogenated silicon. The high-pressure chemistry adroitness is unique in allowing the silane to decompose into the useful hydrogenated form of amorphous silicon, rather than the much less-useful non-hydrogenated form that otherwise would appearance without a plasma reactor. Using pressure in this way is very practical because the optical fibers are so small.

Source: Science Daily (press release)