Over the past few years, the amount of work that has gone into determining the characteristics of silicon nanowires has increased considerably, mostly because they represent the future of the electronics industry, right next to their carbon nanotube cousins. In their search for ever-smaller technologies, manufacturers are pushing the boundaries of physics research close to the ultimate level, and nanowires are at the forefront of the investigation effort.

Determining the mechanical properties of silicon nanowires has thus become something that many research groups around the world are seeking to determine precisely. Scientists at the North Carolina State University (NC State) have only recently managed a breakthrough in the field, when they have determined some of the traits that the small structures have, as opposed to their larger counterparts. “The mainstream semiconductor industry is built on silicon. These wires are the building blocks for future nanoelectronics,” NC State Assistant Professor of Mechanical Engineering Dr. Yong Zhu says.

The expert is the lead researcher on the new project. His team has found out in experiments that the nanowire variety of silicon is considerably stronger than the large-scale one, a discovery that could pave the way for new light-emitting diodes (LEDs), nanoelectronics, nanosensors, and other electronic devices. As interest in the material grew, various studies published in scientific journals reported conflicting results on the traits of the nanowires, so the NC State team decided to investigate the elastic and fracture properties associated with them.

“Our experimental method is direct but simple. This method offers real-time observation of nanowire deformation and fracture, while simultaneously providing quantitative stress and strain data. The method is very efficient, so a large number of specimens can be tested within a reasonable period of time,” NC State PhD student Qingquan Qin, also a coauthor of the new paper, explains. The researchers have used a vapor-liquid-solid synthesis process for obtaining the nanotubes.

“These properties are essential to the design and reliability of novel silicon nanodevices. The insights gained from this study not only advance fundamental understanding about size effects on mechanical properties of nanostructures, but also give designers more options in designing nanodevices ranging from nanosensors to nanoelectronics to nanostructured solar cells,” Zhu concludes.