Silicon Nanowire Technology
Sustaining the shrinking of electronic devices
Moore's law predicts that the number of transistors that can be attached to a microchip will double once every two years. To fit more transistors on a chip, engineers need to design ever smaller transistors. However, there are limits to how much smaller electronic devices can be made, and these are expected to be reached by 2020.
Nanowires, which are incredibly thin – about 20,000 times thinner than a strand of human hair – may be a solution.
Scientists from the Institute of Microelectronics (IME) have developed a technology for fabricating silicon nanowires that is expected to drive the miniaturisation of electronic devices beyond 2020. With this technology, they have come up with a novel transistor architecture in which the gate surrounds the wire channel and multiple nanowire channels can be stacked vertically, making it possible for high-speed logic circuits and memory cells to work at low voltage.
As IME’s nanowire fabrication technology uses silicon, a relatively cheap material, and is compatible with conventional semiconductor technology, it can lead to the low-cost mass production of nanowire devices and circuits with applications in many areas.
One important use of silicon nanowires is in optoelectronics, which deals with electronic devices for generating, emitting, modulating, transmitting and sensing light. The unique quantum characteristics of the nanowires make them very suitable for such applications, and compatibility with current semiconductor technology will allow the integration of optical elements with electronics. This can translate into an overall system which is not only smaller but faster and has more functionality.
Silicon nanowires also offer advantages in thermoelectric cooling or power generation devices due to their improved thermoelectric efficiency. Solar cells and fuel cells stand to benefit from the technology; micro-batteries that use a bundle of silicon nanowires as electrode material can store several times the charge of existing lithiumion batteries with conventional electrodes. Using this silicon nanowire fabrication technology, IME scientists have been able to develop highly sensitive biomedical and environmental sensors.
Last Updated on 18 October 2009