Will Hybrid Circuits Make Silicon a Thing of the Past?

Silicon may soon be rendered obsolete if a new energy-efficient hybrid circuit delivers on its developers' promises.

Researchers from the University of California's Viterbi School of Engineering claim that they have developed a hybrid circuit that combines carbon nanotube(CNT) thin film transistors with other thin film transistors to make a flexible and seamless replacement for silicon chips.

Much like in recent solar cell advances, these two layers of films combine p-type and n-type material to create an extremely energy efficient particle dichotomy. Traditionally, n-type materials are rich with electrons, while p-type materials are electron-starved, but combined, p-type material can help n-type material achieve a level of energy control and efficiency.

Electrical engineer Chongwu Zhou was able to develop this new kind of energy efficient circuit after integrating n-type CNT film transistors with thin film transistors comprised of indium, gallium and zinc oxide (n-type material).

"It's like a perfect marriage," Zhou, said in a recent statement.

The engineer compared the hybridized pairing to the Chinese philosophy of yin and yang, adding, "we are very excited about this idea of hybrid integration and we believe there is a lot of potential for it."

Unlike silicon, CNT technology is extremely flexible, allowing for form-fitting electrode sensors and memory chip bases. This could allow more adaptive monitoring hardware in the emergency room, and could reduce restrictions to ingenuity in computer technology fields.

"The possibilities are endless, as digital circuits can be used in any electronics," said Haitian Chen, who helped develop the first wave of experimental hybrid circuits. "One day we'll be able to print these circuits as easily as newspapers."

To prove these hybrid circuits function with efficiency, Zhou and his team of engineers constructed a scale ring oscillator consisting of over 1,000 transistors. Before this, the largest ring of CNT transistors could only support up-to 200 transistors due to the inefficiency of CNT-based technology alone.

Still, Zhou's "ying-yang" circuit is a long way away from seeing practical application. The next step, the development team explains, is to start testing complicated circuits while they tackle high-demand tasks.

The team hopes to have the circuit ready for commercialization within the next decade.

A study detailing this achievement was published in Nature Communications on June 13.