Nanoimprint Lithography

An anonymous submitter writes "According to BBC News, researchers at Princeton have developed a die-stamp method for chip fabs. The Princeton site claims they've got to 10nm already. The professor in charge has told BBC News Online that they're '20 years ahead of Moore's Law.' Dubious claims aside, it looks like a handy way to bring down prices even if it doesn't improve ultimate top speed."

Comments

Moore's Law

[emf]

Moore's law really has nothing to do with speed even though people think it does.

"More than 25 years ago, when Intel was developing the first microprocessor, company cofounder Gordon Moore predicted that the number of transistors on a microprocessor would double approximately every 18 months. To date, Moore's law has proven remarkably accurate. "

From : http://www.cnet.com/Resources/Info/Glossary/Terms/ mooreslaw.html

Re:Moore's Law

[Reality Master 101]

Actually, you and the CNet link you posted have it wrong, also. Moore predicted transistor density would double, not the number of transistors on a Microprocessor. Here's the reference from the man himself.

10 nm != .1 micron

[GreenPhreak]

10 nm == .01 microns last time I looked.

1 nm = 1e-9 m
1 micron = 1e-6 m

Nanoimprint Lithography

[Anonymous Coward]

I've experimented with this technique a bit, and surprisingly it is very capable of replicating super tiny features. Surprising because the stamps are most commonly made from a flexible polymer material. They are very good at replicating tiny features from a master fabricated using electron beam lithography. One thing that we weren't able to solve was doing alignments between layers, since the stamps tend to be thick and hard to see through. But this is just an engineering issue that we didn't have the time or inclination to solve.

I was just blown away that we were able to fabricate high fidelity microstructures using what basically amount to a rubber stamp!

But how do you make the mold?

[joshv]

This sounds great, but how do they make the mold, what kind of wear and tear is the mold subject to? My guess is that one of these 'nano-imprint' molds is not going to last all that long.

I am assuming they are relying on something like electron beam lithography to create the imprint mold, certainly this would be a cost/time improvement over direct e-beam litho, but it all depends on longevity of the molds.

-josh

Re:But how do you make the mold?

[pz]

Every day, diffraction gratings are created with about 1nm accuracy using macroscopic tools. My father designed one which does just that. It is not impossible to imagine, therefore, that arbitrary features could similarily be scribed.

The machines which create the diffraction gratings are called ruling engines, and, not unlike the methods used to stamp metal currency, the masters are used to make duplicates which then are used to make the work tools. Each stage can be replicated N times, so while there is a limited lifetime of the entire process, N^3 can be quite large.

Environmentally friendly!

[pokeyburro]

Take note of that third section: no nasty chemicals, they claim. If their claim holds, a company using this tech could make a lot of political capital from it.

Natural questions arise: just how dirty is the current process? Will the details of the method really prove to be as clean as they say?

Re:Environmentally friendly!

[Hoi Polloi]

"just how dirty is the current process?"

Have you ever been to a chip fabrication lab? Those places are nasty; cyanide emergency kits on the walls, phosgene and arsine gases. Bad stuff.

Re:Environmentally friendly!

[Zathrus]

Been to? Hell, I used to work at one. Lovely fab safety classes -- "If you ignore the gas leak alarm, please try to die within 6 feet of the door. That's how long the pole hook is to drag your body out."

Not to mention the horror stories about HF (watch your bones melt!), phosphine and other gasses which can kill you before you smell them (but the MSDS lists them as smelling like lemon... go figure), liquid scrubbers like Pirhana that meant no contacts (if the system backblasts the Pirhana would melt the contacts to your eyes), etc.

That said, this process will only eliminate Photolithography... which is the process that uses the fewest of these amazingly nasty chemicals from what I recall. But I worked mostly with PVD/CVD and etchers, so I could be wrong about Photo's chemical usage.

Re:Environmentally friendly!

[Spunk]

So the term "Clean Room" is something of a cruel joke, eh?

chicken and egg

[g4dget]

You still have to make the mold itself, and since it is in actual mechanical contact with the substrate, it won't last anywhere near as long as an optical mask. So, you certainly have to make masters fairly regularly, and those processes may be disproportionately costly and time consuming (electron beam lithography, nanoprobes, etc.).

Altogether, it looks like a nice process, but it's not immediately clear that it will help.

Re:Important Issue

[YourGarbageMan]

The same way they make phase shift masks for optical lithography. They use an ebeam writer to expose a pattern onto a photoresist layer on a quartz substrate. Then they develop the resist, etch away the quartz and then strip the resist. Ebeam writers have very high resolution and printing patterns of this size is not a problem.

10 nm = 4.97 e-11 furlongs

[elsegundo]

If it helps...

A little math

[quintessent]

The observation that the computing power which can be incorporated in a given sized piece of silicon doubles roughly every 18 months was put forward by the head of Intel, Gordon Moore, in 1965. - BBC News.

We're probably 20 years ahead of the curve, - Professor Chou.

Seems a little exaggerated. Let's look at the numbers.

The article says they're 100x as dense (in area) as current technology.

if 2^7=128, then technology needs to double fewer than 7 times.

7 * 1.5 years = 10.5 years, far fewer than the claimed 20 years.

And this technology is still vaporware, so even 10.5 years is exaggerated.

Sounds cool, though. It would be nice if this really worked.