Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Discovery could lead to faster, smaller, cheaper computer chips

20.06.2002


In a discovery that could greatly reduce the size and cost of computer chips, Princeton researchers have found a fast method for printing ultrasmall patterns in silicon wafers.



The method, described in the June 20 issue of Nature, could allow electronics manufacturers to increase the density of transistors on silicon chips by 100-fold while dramatically streamlining the production process. Packing more transistors onto chips is the key to making more powerful computer processors and memory chips.

Researchers in the lab of electrical engineer Stephen Chou used the new technique to make patterns with features measuring 10 nanometers -- 10 millionths of millimeter. The method involves pressing a mold against a piece of silicon and applying a laser pulse for just 20 billionths of a second. The surface of the silicon briefly melts and resolidifies around the mold.


The method eliminates the costly and time-consuming step of etching, or photolithography, which had been the only way to make such small patterns in silicon. While the etching process takes 10 or 20 minutes to make a single chip, Chou’s imprint method accomplishes it in a quarter of a millionth of a second.

"Here you do not need to use all those steps," said Chou. "You just imprint the pattern directly into the silicon. You not only reduce the number of steps, you can do it in nanoseconds."

Chou’s co-authors on the paper are graduate students Chris Keimel and Jian Gu.

In a commentary accompanying the research report in Nature, electrical engineer Fabian Pease of Stanford University wrote that the new method could allow electronics manufacturers to continue the rapid pace of miniaturization that has continued for three decades, but appeared to be running up against fundamental physical limits.

Chou has made a career of breaking what had appeared to be physical limits of miniaturization. In 1996, he developed a method for imprinting nanometer-scale patterns into plastic polymers. That breakthrough greatly simplified the process of making molds, but costly etching was still required to transfer these patterns into silicon.

Chou believed that imprinting would work directly in silicon and could be made to happen much faster.

"People’s intuition is that mechanical processes are very slow, so imprinting cannot be fast," said Chou. "But I knew there is no scientific proof of that. So how do you design an experiment to explore the speed limit of the imprint process?"

The key turned out to be a tool called an excimer laser, which is commonly used in laser surgeries because it can heat just the thinnest surface layer of a material without causing damage underneath. Using conventional etching, Chou made a template of the pattern he wanted out of quartz, which is transparent to the laser beam, and pressed it against the silicon. A brief laser pulse melted the silicon surface around the mold. The silicon does not stick to the quartz.

Revealed by electron microscopes, the patterns the researchers produced look like long, squared-off channels. Each ridge measures 140 nanometers across and is topped by a much smaller ridge just 10 nanometers wide. By comparison, a 10-nanometer ribbon next to a human hair would look like the lead of a mechanical pencil next to a train car.

Chou dubbed the method Laser-Assisted Direct Imprint, or LADI. The University has submitted an invention disclosure, which initiates the process of filing for a patent. He believes the LADI process will mesh well with another of his earlier breakthroughs, his creation in 1996 of the world’s smallest transistor, which requires only a single electron of current. Making common use of such small transistor has been inhibited by lack of a convenient manufacturing process, he said.

Another benefit of LADI, said Chou, is that it eliminates the chemicals used in conventional lithography and is thus more environmentally friendly.

In addition to its commercial applications, the discovery opens an interesting avenue of scientific research, said Chou. Understanding the physics behind melting and solidifying on such small scales will require input from many fields, including materials science, mechanics and microfluidics.

"Scientifically, people are still trying to understand how it works, because it is amazing that it works at all," said Chou.

Steven Schultz | EurekAlert!

More articles from Information Technology:

nachricht Smart Computers
21.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht AI implications: Engineer's model lays groundwork for machine-learning device
18.08.2017 | Washington University in St. Louis

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Molecular volume control

22.08.2017 | Life Sciences

When fish swim in the holodeck

22.08.2017 | Life Sciences

Biochemical 'fingerprints' reveal diabetes progression

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>