Date: 09/07/2012

Reliable EUV light for semiconductor lithography/etching for nodes deeper than 20nm

A start-up research company called Zplasma founded by researchers of University of Washington have found a way to produce Extreme Ultra Violet (EUV) light source from the fusion energy, where Hydrogen elements forms Helium and produce huge light and energy.

Semiconductor industry is looking for reliable EUV light source for making chips below 20nm. The challenge is producing a EUV light which lasts long enough to etch the silicon as per requirement. The present 193-nanometer ultraviolet light is of no use for very deeper nodes. Present techniques to produce EUV light lasts just 20 to 50 nanoseconds. Zplasma's light beam lasts 20 to 50 millionths of a second, about 1,000 times longer, as per the release.

Uri Shumlak, a UW professor of aeronautics and astronautics says "In order to get smaller feature sizes on silicon, the industry has to go to shorter wavelength light. We’re able to produce that light with enough power that it can be used to manufacture microchips.”

UW beam lasts up to 1,000 times longer than competing technologies and provides more control over the million-degree plasma that produces the light, as per the research members.

EUV
The lab equipment includes a small system that measures plasma for electronics applications, attached to a larger tank containing plasma for energy research.

Chip industry need now a 13.5-nanometer light. Such extreme ultraviolet light can be created only from plasmas, which are high-temperature, electrically charged gases in which electrons are stripped from their nuclei, as per the researchers.

The news story from the washington.edu states "The electronics industry is trying to produce this extreme ultraviolet light in various ways. One takes a droplet of tin and shoots it with a laser to make plasma that releases a brief spark of light. But so far this spark is too brief. Chip manufacturers use a $100 million machine to bounce light off a series of mirrors and eventually project the light onto a silicon wafer; each step absorbs some of the light's energy."

"Over the past decade, the primary issue with these extreme ultraviolet light sources is they just can't produce enough power," Shumlak said. "It's a stumbling block for the whole semiconductor industry."

The UW group's specialty is a lower-cost version of a fusion reactor that uses currents flowing through the material, rather than giant magnets, to contain the million-degree plasma. Their method also produces plasma that is stable and long-lived.

"It's a completely different way to make the plasma that gives you much more control," said Brian Nelson, a UW research associate professor of electrical engineering.

EUV
Four capacitors are used to supply up to 10,000 volts to separate the xenon electrons from their nuclei, creating an electrically charged plasma.

"That translates directly into more light output, more power depositing on the wafer, such that you can move it through in some reasonable amount of time," Shumlak said.

A gift last fall from the Washington Research Foundation helped the team shrink the equipment from the size of a broomstick to a new version the size of a pin, which can produce a sharp beam, said in news story.

Zplasma is looking for investors in making use of this technology for the industry.

To hint you what's the latest happening in producing EUV using Tin plasma: Gigaphoton has achieved maximum of 5.2% Conversion Efficiency (CE), with an average of 4.7%, while producing extreme ultraviolet (EUV) energy from tin (Sn) plasma. The industry target is 5.0% CE required for the first generation, production EUV scanner.

To read the news from washngton.edu visit:

http://www.washington.edu/news/articles/plasma-startup-creates-high-energy-light-to-make-smaller-microchips