Silicon
has been established as one of the widely used material in the integrated
circuit since approximately 60 years. It is used to fabricate transistors using
conventional method, where etching of the layers was done to formulate some
structures. However, circuit based on silicon reach its operational speed limit
and does not work above certain temperature. In addition to that, ever
increasing demand of miniaturization has led to the development of advanced
manufacturing technique where nanostructure material plays significant roles
along with the addition of other semiconducting material such as gallium
nitride. It does not only show promise for a new generation of fast, robust
electronic and photonic devices, but also opens up the scope of innovation for
the researchers. Such is the case of three dimensional nanowire transistors,
developed by scientists of University of California.
One of the technical problem silicon substrate
is facing over the years is the lattice parameter mismatch with other
materials. Match is necessary due to the growth technique associated with
integrated circuit, which in turn faces major limitation as far as the growth
material is concerned. To overcome these challenges, nanowire made of semiconductor
materials was made on top of silicon surfaces. Due to the lower surface area of
nanowire which acquires the place of silicon, problem of lattice mismatch does
not arise. The new technology could be used, for example, to build sensors that
can operate under high temperatures, for example inside aircraft engines. In
the near future, machine will be dependent on a variety of sensors and control
systems that operate in extreme environments, such as motor vehicles, boats,
airplanes, terrestrial oil and ore extraction, rockets, spacecraft, and bodily
implants.
The
researchers have been able to make these nanowires operate as transistors, and
combine them into more complex circuits as well as devices that are responsive
to light. They have developed techniques to control the number of nanowires,
their physical characteristics and consistency. The technology also leverages
the well-established technology for manufacturing silicon integrated circuits.
