Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breakthrough yields simple way to make microscopic electronics

23.07.2004


Scientists achieve smallest-ever spacing in nanoscale structures

In a breakthrough that could lead to dramatically smaller memory chips and other electronic components, Princeton scientists have found a way to mass produce devices that are so small they are at the limit of what can be viewed by the most powerful microscopes.

The achievement is an advance over current techniques, which require expensive and time-consuming procedures to create anything so small. The technique offers a relatively simple, low-cost production method that may lead to greater memory capacity and lower costs for computers, digital cameras and other devices. In addition, the scientists achieved unprecedented success in packing the minute structures into dense clusters.



The researchers, led by engineering professors Stephen Chou and Stephen Lyon, used a technique known as nanoimprinting, in which they press a mold into a layer of softened plastic on a silicon wafer, making microscopic patterns on the surface of the plastic. The patterns can then be transferred to the silicon where they could form the basis of miniature electronic circuits that store digital information.

The goal of the research was to determine how small and dense a pattern could be pressed into plastic with nanoimprinting, said Chou, who invented nanoimprinting in 1994. "This work really pushes the limit down to a few molecules in size," he said.

The scientists published their results in the June 28 issue of Applied Physics Letters. The other authors of the paper include graduate students Michael Austin, Wei Wu, Mingtao Li and Zhaoning Yu and postdoctoral researchers Haixiong Ge and Daniel Wasserman.

The researchers reported that they created tall, thin ridges only 5 nanometers (5 millionths of a millimeter) wide. The researchers believe they made ridges even narrower than 5 nanometers, but could not confirm the results with existing microscopes. "So we still do not know what the absolute limit is," said Chou.

An important aspect of the achievement is not just the small size of the ridges, but also the amount of space between the ridges, Chou said. The spacing, known as "pitch," ultimately determines the density of electronic memory that can be packed onto a chip. In their published paper, the scientists reported that they achieved a 14-nanometer pitch between ridges. They have since reduced it to 12 nanometers. That spacing is a 20-fold reduction compared to the state-of-the-art techniques used in making today’s most advanced computer chips and would result in 400 times more memory in a two-dimensional memory chip, Chou said.

The current method for making nanoscale devices is to carve each piece individually with a beam of electrons, a technique called electron-beam lithography. That process does not achieve the 14-nanometer pitch of nanoimprinting and requires equipment that is much more expensive than anything used in Chou’s technique.

The key to the result was the collaboration between the labs of Chou and Lyon and the combination of their different areas of expertise. Chou, the pioneer of nanoimprinting, was looking for improvements in the molds he uses for pressing patterns into plastics. His standard method for making a mold was to use electron-beam lithography to carve the desired pattern in a piece of silicon, which is then pressed into plastic. This approach is limited by the narrowness of the electron beam, which carves out a U-shaped channel about 20 nanometers wide.

To improve on this level of precision, Chou turned to Lyon, an expert in a technology called molecular-beam epitaxy, which Lyon uses to grow flat sheets of crystals just a few molecules thick. Members of Lyon’s lab grew alternating layers of two materials until they had a wafer hundreds of layers thick. Researchers in Chou’s lab then cut the wafer, exposing the edges of the layers. They applied a chemical that ate away one of the two materials but not the other. The result was a very fine comb-like pattern in which all the teeth and valleys were perfectly smooth and square with atomic precision. The researchers used this creation as their mold.

This mold-making process, though time-consuming, would need to be done only once in setting up a manufacturing process, said Chou. Once the mold is made, it can be used to make countless copies very rapidly.

The research is the latest in a series of nanoimprinting advances Chou has made in recent years. In 2003, Technology Review magazine, published by the Massachusetts Institute of Technology, identified Chou’s work with nanoimprinting as one of "10 emerging technologies that will change the world." His latest study was funded in part by the Department of Defense Advanced Research Projects Administration.

Steven Schultz | EurekAlert!
Further information:
http://www.princeton.edu

More articles from Information Technology:

nachricht Information integration and artificial intelligence for better diagnosis and therapy decisions
24.05.2017 | Fraunhofer MEVIS - Institut für Bildgestützte Medizin

nachricht World's thinnest hologram paves path to new 3-D world
18.05.2017 | RMIT University

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>