Tyndall National Institute create first junctionless transistor
By Alan Brandon
March 16, 2010
A team of scientists at the Tyndall National Institute in Cork, Ireland has created what they claim is the world's first junctionless transistor. The invention represents a breakthrough in transistors and nanoelectronics, and has the potential to revolutionize microchip manufacturing.
The approach uses a control gate around a silicon nanowire to control the passage of electrons without the use of junctions.
The Tyndall team, led by Professor Jean-Pierre Colinge, says the transistors are relatively easy to make and could help to extend Moore's law and reduce manufacturing costs.
The transistor is the fundamental building block in electronic devices. On silicon computing chips, the number of transistors reflects the relative amount of processing power the chip has. Since the 1970s the number of transistors built on a silicon chip has grown from just a few hundred to more than two billion transistors on a single chip. Today’s electronic devices are driving the need for more transistors on each chip, while also requiring semiconductor chips that are smaller, more energy efficient, and more cost effective. The conventional transistor architectures used for the last 40 years can no longer keep up with this demand.
Current transistors are based on junctions, which are formed by placing two pieces of silicon with different polarities side-by-side. Controlling the junction allows the current in the device to be switched on and off. Fitting more transistors on a chip requires more precise fabrication methods, which greatly increases the cost of the chip.
Tyndall’s transistor architecture eliminates the junctions and instead uses a control gate around a silicon nanowire to carry the current. The current flow is controlled by the control gate electrically “squeezing” the nanowire using an easy-to-fabricate ring structure. The Tyndall researchers were able to create silicon nanowire only a few dozen atoms in diameter using electron-beam writing techniques.
Colinge and his researchers say the architecture is compatible with current CMOS manufacturing processes, and expect that their design will prove particularly applicable in the manufacturing of transistors at the 10-nanometer scale. The team also believes that their junctionless devices have the potential to operate at faster and use less energy than the conventional transistors used in today's microprocessors.
Tyndall has been in discussions about the new technology with leading semiconductor companies around the world, and report a lot of interest in further development and possible licensing of the technology.
The research was published in Nature Nanotechnology.
For more information visit the Tyndall National Institute.