Plasma etching pushes the limits of a shrinking world

Nov 10, 2011

Plasma etching (using an ionized gas to carve tiny components on silicon wafers) has long enabled the perpetuation of Moore's Law -- the observation that the number of transistors that can be squeezed into an integrated circuit doubles about every two years. Without the compensating capabilities of plasma etching, Moore's Law would have faltered around 1980 with transistor sizes at about 1 micron (the diameter of a human hair is approximately 40-50 microns wide). Today, etch compensation helps create devices that are smaller than 20 nanometers (1,000 times smaller than a micron).

Now more than ever, plasma etch technology is used to extend semiconductor device fabrication into the nanoelectronics age -- and technologists at Lam Research are developing techniques for the manufacture of even smaller, faster, and more densely packed multi-functionality chips. The question now is how much smaller and faster can the go? The answer has much to do with plasma etch technology.

One of the most critical steps of , plasma etching creates finely delineated features in the conductive and dielectric (insulating) layers on . Plasma etch techniques can also compensate for limitations in lithography, the optical process that develops the "template" for creating nanoelectronic structures on . Transistors and other components are now so small that lithography can no longer produce templates with the necessary precision to pack millions of onto small integrated circuits. While researchers are working on new lithography technology ( or ) to overcome this limitation, plasma etching is used to compensate for lithography's imperfections by filling in gaps and smoothing out edges of the tiny components on the chip (Figure 1). Plasma etching also enables other techniques that extend current lithography capabilities, including double patterning (a method of overlaying two patterns to achieve the original design) and directly shrinking structures smaller than the template dimensions.

Yet, plasma etching itself is now facing the fundamental limits imposed by the basic laws of physics and chemistry. Because etching is involved in forming the critical structures of every semiconductor device, Lam Research technologists are learning to better control the behavior of the various components of the plasma (a gaseous mixture of charged and neutral particles) during the etching process. The ultimate goal would be to selectively etch one layer of atoms at a time (atomic-layer etching or ALE), without disturbing the bulk of the material underneath.

Over the next 5 years, improving plasma etch technology will be key to extending Moore's Law further and manufacturing the next-generation of consumer electronics devices.

Explore further: Ray tracing and beyond

Provided by American Physical Society

4 /5 (1 vote)
add to favorites email to friend print save as pdf

Related Stories

Trenches create memory space

Sep 12, 2006

The requirements are tightening up. Computers are having to become more and more efficient. A new technology boosts memory capacity: etching the silicon wafer creates deep trenches that increase its capacity ...

Custom-Sized Microlenses

Aug 30, 2004

Optical components have joined the trend towards miniaturization. There have, however, been no methods available thus far to produce custom-sized glass lenses. A new process now enables the low-cost, high-volume manufacture of ...

Nuclear fusion research key to advancing computer chips

Aug 18, 2009

( -- Researchers are adapting the same methods used in fusion-energy research to create extremely thin plasma beams for a new class of "nanolithography" required to make future computer chips.

Recommended for you

New method for non-invasive prostate cancer screening

9 hours ago

Cancer screening is a critical approach for preventing cancer deaths because cases caught early are often more treatable. But while there are already existing ways to screen for different types of cancer, ...

How bubble studies benefit science and engineering

10 hours ago

The image above shows a perfect bubble imploding in weightlessness. This bubble, and many like it, are produced by the researchers from the École Polytechnique Fédérale de Lausanne in Switzerland. What ...

Famous Feynman lectures put online with free access

11 hours ago

( —Back in the early sixties, physicist Richard Feynman gave a series of lectures on physics to first year students at Caltech—those lectures were subsequently put into print and made into text ...

Single laser stops molecular tumbling motion instantly

15 hours ago

In the quantum world, making the simple atom behave is one thing, but making the more complex molecule behave is another story. Now Northwestern University scientists have figured out an elegant way to stop a molecule from ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Nov 14, 2011
A Figure 1 is missing http://matthieu.l...ples.png