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Low Voltage/Low power design in future nodes

Next generation computer chips

The world’s growing need for nanocomputers that are even smaller, faster, and more energy-efficient can possibly be met within a few years. Researchers are in full swing designing circuits with very large memory capacity and very low power consumption. They anticipate that this can be particularly important for the spread of portable, wearable, or implantable chips for monitoring different body functions and storing biomedical data.
The photo shows Assistant Professor Moradi.

The traditional transistors in microprocessors are planar tructures. The next generation of transistors has an advanced geometric pattern in three dimensions, and this provides considerably better control of the channel, less leakage current, low-voltage memory,

In a new international collaboration, engineers at Aarhus University will play a key role in designing integrated circuits using new transistors. These can be used in nanocomputers with super memory capacity and ultra-low power consumption.

Researchers at Aarhus University have entered into a formal three-year collaboration with the Interuniversity Microelectronics Centre (imec) to develop and test a completely new and potentially ground-breaking technology.

Imec is a strong partner and a world leader in new developments in microelectronics and nanoelectronics.

Industrial restructuring in sight
In the coming years, researchers will look at opportunities for a new type of electrical circuit that could very well pave the way for a historically large industrial restructuring, according to Assistant Professor Farshad Moradi.

He has been working extensively for years with digital and analogue circuits in nanoscale technologies, and he has a privileged insight in the latest computer technology trends.

“Development in computer technology has been exponential for more than forty years where the number of transistors in microprocessors has doubled about every second year according to what computer scientists know as Moore’s law. There’s much to indicate that we’re at a turning point and that – with the latest technology – we can develop chips with properties that could pave the way for a new chapter in the world history of electronics,” he says.

Microprocessors are traditionally manufactured using a so called complementary metal–oxide–semiconductor (CMOS) technology. One of the major disadvantages of using this technology in its nano-scale regime is that the leakage current of the electronic device increases significantly. This means, in practice, that whether referring to a mobile phone, an ECG monitor or some other sort of device, it will relatively quickly run out of power because it uses the battery’s capacity even when on standby mode.

Low power consumption and super memory
As computer technology gets used in new contexts in which battery capacity is crucial, this leakage current becomes a bigger and bigger problem. In other words, the current technology does no longer match the world’s expanding need for small computer chips with low leakage and high scalability. It applies particularly within the field of biomedicine where very small computers can be sewn into clothes or implanted in the body.

Here it is memory and power consumption that represent the major innovation challenge by far.

“Just to take an example, if you want to measure brain activity over a period of time via a small computer surgically implanted under the scalp, then it’s obvious that it must be capable of saving battery power and storing large amounts of data,” explains Assistant Professor Moradi.

Three-dimensional transistor structure
The technology that can make this a realistic scenario is called FinFET and, fundamentally it is based on a three-dimensional transistor structure that conducts the power.

According to Assistant Professor Moradi, this can reduce power consumption in digital circuits by several orders of magnitude, at the same time as making it possible to provide smaller units with more functionality and memory.

The Aarhus University researchers have the task of testing and further developing the technology and preparing for an industrial conversion to new nano-sized circuits.