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(萌妹社区Org.com) -- An approach pioneered by researchers at North Carolina State University gives scientists new insight into the way silicon bonds with other materials at the atomic level. This technique could lead to improved understanding of and control over bond formation at the atomic level, and opportunities for the creation of new devices and more efficient microchips.

Manufacturers build silicon-based devices from layers of different materials. Bonds 鈥� the chemical interaction between adjacent atoms 鈥� are what give materials their distinctive characteristics. 鈥淓ssentially, a bond is the glue that holds two atoms together, and it is this glue that determines material properties, like hardness and transparency,鈥� says Dr. Kenan Gundogdu, assistant professor of physics at NC State and co-author of the research. 鈥淏onds are formed as materials come together. We have influenced the assembly process of silicon crystals by applying strain during bond formation. Manufacturers know that strain makes a difference in how bonds form, but up to now there hasn鈥檛 been much understanding of how this works on the atomic level.鈥�

Gundogdu, along with Dr. David Aspnes, Distinguished University Professor of 萌妹社区ics, and doctoral candidate Bilal Gokce, used optical spectroscopy along with a method of analysis pioneered by Aspnes and former graduate student Dr. Eric Adles that allowed them to examine what was happening on the atomic scale when strain was applied to a silicon crystal.

鈥淪train has been used to affect overall chemistry for a long time,鈥� Aspnes says. 鈥淗owever, no one has previously observed differences in chemical behavior of individual bonds as a result of applying strain in one direction. Now that we can see what is actually happening, we鈥檒l gain a much better understanding of its impact on the atomic scale, and ideally be able to put it to use.鈥�

According to Gundogdu, 鈥淎pplication of even small amount of strain in one direction increases the chemical reactivity of bonds in certain direction, which in turn causes structural changes. Up to now, strain has been applied when devices are made. But by looking at the effect on the individual atomic bonds we now know that we can influence chemical reactions in a particular direction, which in principle allows us to be more selective in the manufacturing process.鈥�

The research appears online in the Sept. 27 Proceedings of the National Academy of Sciences.

鈥淲hile we are able to exert some directional control over reaction rates, there remains much that we still don鈥檛 understand,鈥� Aspnes adds. 鈥淐ontinuing research will allow us to identify the relevant hidden variables, and silicon-based devices may become more efficient as a result.鈥�