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Research Discovery Could Revolutionize Semiconductor Manufacturing

Soulskill posted about a year ago | from the nobody-thought-to-use-playdoh-before-this dept.

Technology 64

New submitter arobatino writes "A new method of manufacturing semiconductors which eliminates the substrate (in other words, no wafer) could be much faster and cheaper. From the article: 'Instead of starting from a silicon wafer or other substrate, as is usual today, researchers have made it possible for the structures to grow from freely suspended nanoparticles of gold in a flowing gas. "The basic idea was to let nanoparticles of gold serve as a substrate from which the semiconductors grow. This means that the accepted concepts really were turned upside down!" Since then, the technology has been refined, patents have been obtained and further studies have been conducted. In the article in Nature, the researchers show how the growth can be controlled using temperature, time and the size of the gold nanoparticles.'"

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64 comments

expect to be able to ... p-n diodes (4, Informative)

RichMan (8097) | about a year ago | (#42124255)

That is like 1950's technology levels. A long time before they can make million gate devices.

There are many many problems associated with replicating sub-nanometer scale patterns on a ground flat substrate. If they don't have a planaer substrate they are going to have lots of problems creating the required imaging patterns. Note that at the current scales you can't print a | object as a simple | you have to make it look like an I, essentially doing what is called dog-boneing because of eteching and diffraction effects. And multiple parallel lines have big problems with diffraction effects.

So currently it seems without a substrate then can make ...... a single p- or n- type semiconuctor material that is unsuitable for anything else.

Re:expect to be able to ... p-n diodes (0, Informative)

Anonymous Coward | about a year ago | (#42124343)

Please don't use ellipses to ...... your sentences. It is ............ to follow your writing.

Re:expect to be able to ... p-n diodes (2, Funny)

Anonymous Coward | about a year ago | (#42124525)

Agree. It is much clearer to (drum roll) make the ellipses into drum rolls. Terminating Tadah's! can also add a sense of (drum roll) occasion. Tadah!

Re:expect to be able to ... p-n diodes (5, Funny)

Anonymous Coward | about a year and a half ago | (#42124869)

Eh, an ellipsis can be fine in the middle of a sentence. His sin is the number of periods.

There are three periods in an ellipsis. Three.

Understand, everyone? Three shall be the number of periods, and the number of periods shall be three. Four periods thou shalt not add, neither addest thou two periods, excepting that thou then proceed to three. Five is right out.

Re:expect to be able to ... p-n diodes (1)

runeghost (2509522) | about a year and a half ago | (#42125555)

Someone with mod points, plz mod parent up. It's funny AND true.

Re:expect to be able to ... p-n diodes (1)

a_hanso (1891616) | about a year and a half ago | (#42126177)

THERE ARE FOUR PERIODS!!!

Re:expect to be able to ... p-n diodes (1)

djl4570 (801529) | about a year and a half ago | (#42127155)

Are you mistaking lights for periods?

84 days? (1)

Taco Cowboy (5327) | about a year and a half ago | (#42126353)

There are three periods in an ellipsis. Three.

Lemme see ... 28days X 3 ... an ellipsis is equal to 84 days?

Re:expect to be able to ... p-n diodes (3, Funny)

Anonymous Coward | about a year ago | (#42124475)

Tell me more about this porn-type semiconductor material. Do you have a link?

Re:expect to be able to ... p-n diodes (0)

Anonymous Coward | about a year and a half ago | (#42124645)

blah blah blah you're missing the bigger picture
something green is being replaced with gold.
RON PAUL RON PAUL RON PAUL

Re:expect to be able to ... p-n diodes (0)

Anonymous Coward | about a year and a half ago | (#42125873)

essentially doing what is called dog-boneing

  Yay, bestiality!

Re:expect to be able to ... p-n diodes (1)

djl4570 (801529) | about a year and a half ago | (#42127129)

So your point is that this is the Wright Flyer of a new technique? If so I look forward to the next Glenn Curtis and the corresponding era of biplanes.

gold is a contaminant (2, Informative)

Anonymous Coward | about a year ago | (#42124257)

gold is a very severe contaminant for silicon, and many other semiconductors.
It sits energy wise in the center of the band gap and kills mobility with traps.

Gold is rigorously excluded from silicon FABS, not even let in the same room.

Re:gold is a contaminant (2)

ChrisMaple (607946) | about a year and a half ago | (#42125071)

Gold is rigorously excluded from silicon FABS, not even let in the same room.

Except when it isn't. It was used a great deal in the early years (1960s, 1970s ?) to improve turnoff time in diodes and TTL logic.

Re:gold is a contaminant (3, Informative)

phaserbanks (1977290) | about a year and a half ago | (#42125927)

Yep. Sometimes you want to introduce recombination centers to kill the lifetime. Nowadays they zap the wafer with radiation to do this.

Re:gold is a contaminant (1)

gagol (583737) | about a year and a half ago | (#42126889)

I am curious about this process, anyone have a source?

Re:gold is a contaminant (3, Funny)

Neil Boekend (1854906) | about a year and a half ago | (#42127245)

Depends on the radiation you want. Americium is a readily available alpha radiation source and I probably have a couple of grams of it. Radium is also good as alpha source and easily available to but it's a bit spread out in normal houses. For gamma sources you may use gamma ray bursts, but since they are deep-space based I don't know whether anyone can claim to have them. I do not know where you'd get a beta ray source as a consumer.

Re:gold is a contaminant (1)

gagol (583737) | about a year and a half ago | (#42127591)

LOL, I was refering to source articles material. Good thing I was not specific as you would not have enlightened my day with your serious humour. I have no intention to use a smoke detector as heat sink... that would be very, very stupid. I am curious as to foundries radiating their wafers to shorten the life of their products. After all, they seek good yields and that would kinda go against it. I will file this meme under "urban legends" or "stuff-mythbusters-should-test" until further evidence.

Re:gold is a contaminant (1)

Tim the Gecko (745081) | about a year and a half ago | (#42129101)

I am curious as to foundries radiating their wafers to shorten the life of their products.

I think you misunderstood the phrase "introduce recombination centers to kill the lifetime". The lifetime being referred to is the lifetime of excess electrons/holes. So it's about speeding the devices up, not about making them fail at some time in the future.

Re:gold is a contaminant (1)

phaserbanks (1977290) | about a year and a half ago | (#42179703)

They use electron radiation. The radiation creates defects in the crystal lattice. Those defects act as recombination centers for holes and electrons. The increased recombination rate correspondingly increases the gain of bipolar transistors.

Like Tim the Gecko said, we're talking about carrier lifetime (Tau), not device lifetime.

Re:gold is a contaminant (3, Informative)

crgrace (220738) | about a year and a half ago | (#42125601)

Gold is rigorously excluded from silicon FABS, not even let in the same room.

Actually gold is the highest quality metal for bondwires or top-level bondpad metalization. You're right that gold is a severe contaminant, but it is also a very good conductor, and is easy to work with. It most certainly used extensively in fabs, although care is taken not to contaminate. I used gold interconnect in a chip just a few months ago, in a very up-to-date process.

The vast majority of chemicals used in a fab will severely degrade circuits if they are introduced into the process at the wrong time or in the wrong way. Gold is not a special exception here.

Re:gold is a contaminant (1)

Neil Boekend (1854906) | about a year and a half ago | (#42127291)

Most discrete wire bonding processes are moving from gold to copper. Not due to contamination, but due to cost. Gold costs E700 per km of 23 mu wire, copper costs about 70. Copper is difficult to master though.
If you are producing 1 billion SMD transistors a day then the few milimeters of gold wire in each transistor are starting to count.

Re:gold is a contaminant (1)

crgrace (220738) | about a year and a half ago | (#42130383)

Most discrete wire bonding processes are moving from gold to copper. Not due to contamination, but due to cost. Gold costs E700 per km of 23 mu wire, copper costs about 70. Copper is difficult to master though.
If you are producing 1 billion SMD transistors a day then the few milimeters of gold wire in each transistor are starting to count.

I agree with you 100%. The original comment indicated gold is not used in semiconductor processing, and I was pointing out that was not true. Our stuff is lower volume so we're still using gold bondwires (can't justify the expensive equipment upgrade).

Re:gold is a contaminant (1)

mk1004 (2488060) | about a year and a half ago | (#42131565)

Aluminum bond wires are used extensively as well, and have been for many years.

Re:gold is a contaminant (0)

Anonymous Coward | about a year and a half ago | (#42128303)

Gold is used only after everything is done, usually when the chip is finished (encapsulated in oxide) and cut. Gold is strictly forbidden near the front end of line (fabrication of the transistors)

Right now "only" nano-wire (2)

Morpf (2683099) | about a year ago | (#42124273)

...but if they really manage to make circuits I am really impressed.

Is gold is cheaper than silicon? (0)

Anonymous Coward | about a year ago | (#42124379)

Otherwise I think they'll have trouble selling these things.

Re:Is gold is cheaper than silicon? (1, Informative)

marcosdumay (620877) | about a year ago | (#42124573)

Yes, it is.

The amount of gold this process would use (if it actualy created a circuit) is incredibly low (much less than the amount of silicon in a current chip), and gold is an order of magnitude cheaper than purified silicon.

Re:Is gold is cheaper than silicon? (4, Informative)

viperidaenz (2515578) | about a year and a half ago | (#42124755)

If gold were an order of magnitude cheaper than a silicon wafer Intel would be making a huge loss on their processors.
a 200mm wafer is 0.775mm thick. A quick google says this is about $1200. I'm not sure when this was, but the price keeps dropping.
If you made a 200mm x 0.775mm gold disk, it would weigh 470g. The price of gold is currently $55.40/g. That's a $26,000 hunk of metal, 20x the price of silicon wafer.
Going on the 'order of magnitude cheaper' If a 200mm wafer cost $260,000 for 31,415mm3 of surface area it would be impossible to get more than 60 xeon 8800's (513mm2) (much less, since the die in a CPU is square so the edges re unusable and there is probably a need for cutting lines, not to mention yield), The raw die alone would cost $4,333.

Re:Is gold is cheaper than silicon? (0)

Anonymous Coward | about a year and a half ago | (#42124891)

on the scale that intel makes them a full wafer costs about a buck for the silicon price (maybe less as silica is very abundant at the eaths crust)
its all the process that they do to that wafer that make the price go up
the industrial wherehouse guys who buy out the fabs when they go out of bussines throw the wafers away --they are worthless except for curiosity value
its getting your fab set up and EVERYTHING all the process worked out that costs big bucks

Re:Is gold is cheaper than silicon? (1)

TubeSteak (669689) | about a year and a half ago | (#42125009)

Here's a website with some numbers so you can make a proper comparison between the cost of silicon and gold: http://pvinsights.com/ [pvinsights.com]

Semiconductor grade polysilicon = PV Grade Poly Silicon

Re:Is gold is cheaper than silicon? (2)

viperidaenz (2515578) | about a year and a half ago | (#42125243)

Those prices are not related to the price of a silicon wafer used to manufacturing semiconductor devices. Check out http://www.gsaglobal.org/email/2010/general/0222w.htm [gsaglobal.org] in 2009 a 200mm wafer cost about $780. Silicon is much lighter than gold, so a wafer would be much less than 470g. Very, very far off the $22/kg for the silicon used in solar panels.

Re:Is gold is cheaper than silicon? (0)

Anonymous Coward | about a year and a half ago | (#42125549)

Those prices are for fully-processed wafers, not raw silicon wafers (which are significantly cheaper). Certainly not $22/kg, but still much cheaper than $780.

Re:Is gold is cheaper than silicon? (3, Interesting)

phaserbanks (1977290) | about a year and a half ago | (#42125965)

Our foundry uses 200 mm wafers. I think the cost is around $20 per wafer. I don't know, because the substrates are so cheap, they don't even charge us. Epi is a little more expensive because of the extra processing -- maybe $50.

I imagine the cost scales with wafer diameter. 200 mm is relatively old technology.

Re:Is gold is cheaper than silicon? (1)

GerryGilmore (663905) | about a year and a half ago | (#42125205)

Look - obviously they're talking about a radically different technique of manufacturing so it's a little bit of apples and oranges. Having said that, you're fundamentally correct in that the even more radical difference in price of the basic building blocks makes it questionable as to the ultimate cost effectiveness. BTW, kudos to these guys for pushing the envelope!!!

Re:Is gold is cheaper than silicon? (1)

viperidaenz (2515578) | about a year and a half ago | (#42125403)

I realise the techniques are completely different. I was correcting the false statement "gold is an order of magnitude cheaper than purified silicon."

Re:Is gold is cheaper than silicon? (1)

artor3 (1344997) | about a year and a half ago | (#42125725)

a 200mm wafer is 0.775mm thick. A quick google says this is about $1200. I'm not sure when this was, but the price keeps dropping.

Either that's old data, or the company selling the wafers was marking them up, or both. In my company's fab, 200 mm wafers cost around half that.

However, you are forgetting a crucial component: wafers may start that thick, but that's only for mechanical reasons. Prior to packaging the individual die, they get ground down to just ~100 um thickness. If they're growing individual chips instead of shuttling a big wafer around, then perhaps the gold layer only needs to be ~50 um instead of ~750 um. You also don't have wasted substrate around the edge of the wafer. That should at least come close to evening out the 20x difference you calculated. And then you can account for time savings, and perhaps some other advantages, and it starts to look like this tech might have some promise.

The bigger flaw I see is how much the price of gold fluctuates due to speculators. They've driven it up by 500% over the past ten years. Maybe it'll even out or go back down, but maybe not. Lots of companies are moving away from gold bond wires because of it, so I can't imagine many companies wanting to become more dependent on the price of gold.

Re:Is gold is cheaper than silicon? (1)

viperidaenz (2515578) | about a year and a half ago | (#42126245)

It acknowledge it is a completely different manufacturing technique and they're not comparable. As explained in another post I was correcting the false statement of "and gold is an order of magnitude cheaper than purified silicon." Also, you're right about the $1200 price. I found a 2009 price for 200mm wafers is about $780. The inflation adjusted price for gold back in 1994 is $20,000/kg. (in 1994 dollars it was around $13,000). The lowest point in the last 20 years was around 2001, about $10,000/kg or $13,000 adjusted for inflation so I'll give you that one.

Re:Is gold is cheaper than silicon? (1)

budgenator (254554) | about a year and a half ago | (#42131975)

There is no reason that I can think of for the gold substrate to have any thickness as we commonly think of other than being able to physically handle the material. Gold has been beaten into leaf for 5000 year and goldleaf is 0.0001016 mm thick, I'm sure even that is thick compared to what they can do with gaseous deposition where layers thin enough to see through are common. All they need is something solid enough to grow some silicon crystals on.

Re:Is gold is cheaper than silicon? (1)

viperidaenz (2515578) | about a year and a half ago | (#42133449)

Yet again, I was correcting the false statement "gold is an order of magnitude cheaper than purified silicon."
Do slashdot users have reading comprehension problems?

Re:Is gold is cheaper than silicon? (1)

marcosdumay (620877) | about a year and a half ago | (#42133673)

Silicon prices keep dropping, and gold prices keep increasing... And my figures are quite old.

I stand corrected.

The first rule of semiconductor manufacture is... (3, Insightful)

namgge (777284) | about a year ago | (#42124431)

...if you believe your new process/material can be developed to the point where it can compete with traditional silicon devices and/or processing methods you are wrong.

Only if you have an application, such as LEDs where the laws of physics say silicon can't possibly compete is there any chance you will succeed. And even then the chances are you are still wrong.

namgge

Re:The first rule of semiconductor manufacture is. (1)

marcosdumay (620877) | about a year and a half ago | (#42124609)

There will be at least one time that some other process came from nowhere and beat silicon litography in nealy all aspects. (The laws of physics almost assure that.)

The only questions are "when?", "what process?" and "will it come while we still have Moore's law?"

Re:The first rule of semiconductor manufacture is. (1)

geekoid (135745) | about a year and a half ago | (#42125441)

" "will it come while we still have Moore's law?""
we don't have it now. Haven't for years. as a reminder: Double the transistors for half the price per cm2.
When was the last time the number of transistors per cm2 doubles in 18 months? 2203? 2004?

Re:The first rule of semiconductor manufacture is. (1)

dylan_- (1661) | about a year and a half ago | (#42127955)

When was the last time the number of transistors per cm2 doubles in 18 months? 2203? 2004?

Actually, it's every 2 years. The 18 month period was from David House and referred to computing power (due to the combination of transister count increasing and speed increasing).

And the answer to your question would appear to be 2011 [wikipedia.org] :)

Re:The first rule of semiconductor manufacture is. (1)

marcosdumay (620877) | about a year and a half ago | (#42133575)

It's not per cm2. It's per chip. Highter yelds are also part of Moore's law.

The law is as strong as ever, and probably will hold until the next fabs generation (about 7 years). After that, it's only guesses.

Re:The first rule of semiconductor manufacture is. (4, Informative)

crgrace (220738) | about a year and a half ago | (#42125643)

There will be at least one time that some other process came from nowhere and beat silicon litography in nealy all aspects. (The laws of physics almost assure that.)

Not so sure about that. Lithography is one of the most highly developed technologies in the history of the world, and has gone far, far deeper than most people expected as early as the 1980s. Proposal after proposal has been made to replace lithography (e.g. e-beam, MBE, etc) but all have to relegated to niche status.

Semiconductor lithography itself is highly, highly leveraged from printing processes going back hundreds of years. With this much brain power and inertia behind it I would be really, really surprised if something beats it in "nearly all aspects". Some aspects, maybe, and lithography may finally hit a show-stopper, but there won't be an "oh my, what a breakthrough" type thing to replace it. I agree it has to be replaced to maintain Moore's law, but it is already beyond comprehension advanced.

Lithography (0)

Anonymous Coward | about a year and a half ago | (#42131411)

Lithography is one of the most highly developed technologies in the history of the world, and has gone far, far deeper than most people expected

Except, of course, when it comes to lithography of ink on paper. In print media, it is being dumped in favor of a more flexible and far cheaper disruptive technology.

Re:The first rule of semiconductor manufacture is. (1)

viperidaenz (2515578) | about a year and a half ago | (#42124783)

Silicon is still used in high power LED's. Cree use silicon carbide.

Not really (3, Insightful)

Chemisor (97276) | about a year ago | (#42124531)

> patents have been obtained

I guess it won't revolutionize anything after all; or at least not for another 20 years.

Re:Not really (2)

viperidaenz (2515578) | about a year and a half ago | (#42124809)

All current techniques are patented too. If they weren't why would someone spend all this research trying to find alternatives. Sometimes patents do help innovation, just never in the software realm.

Somewhat misleading headline (4, Informative)

Hazelfield (1557317) | about a year ago | (#42124537)

This is very cool, but it's got a really long way to go before it can be used to build anything remotely like an integrated circuit. I'm also not sure the benefit will be that large since the wafer cost isn't a very big part of the cost of making integrated circuits today. What I think it can be great for is solar cells, nanotubes and other products where getting rid of the wafer will solve two problems: the cost and the size. If you can make an arbitrarily large solar cell panel, that's a real advantage over wafer-based manufacturing methods.

more gold in semiconductors (0)

Anonymous Coward | about a year and a half ago | (#42124741)

means more gold in my bucket
ive got several ounces saved up already all of it from chips and circut boards. the only problem is finding a reputable HONEST buyer near my home
i have to send it too illinois from california as it is, and i always stress out during shipping that something will happen
im sure these guys will figurre out how to minimize the gold usage but untill they find a happy spot they always go overboard
more power to them

Re:more gold in semiconductors (1)

budgenator (254554) | about a year and a half ago | (#42132273)

Seriously that's not a problem, just send direct to a refiner/assay company like Garfield Refining [garfieldrefining.com] , they'll take anything except mercury, precious scrap metal, grindings, floor sweepings, vacuum cleaner bags, Dental labs and jewelry repair shop even rip up their carpets and send them in and frequently get a check back big enough to pay for the new carpet.

next thing (1)

MakersDirector (2767101) | about a year and a half ago | (#42124921)

Next thing ya know, they are going to 'invent' a 'processor' that is free of mass, tethered to electricity or energy....

And they're going to call it Skynet.

Why, because OHH that's NEVER been done before...

Cmon. How long's this cycle gonna continue, guys? We've been down this road before.

We're all Source Code, WE GET IT ALREADY!

Components? (3, Informative)

hacksoncode (239847) | about a year and a half ago | (#42125149)

I'm getting the impression from the article that they are proposing to use this technique to build semiconductor *components* such as standalone transistors, diodes, etc., etc.

That seems much more feasible than what is implied by the title of this post.

Re:Components? (2)

crgrace (220738) | about a year and a half ago | (#42125663)

I'm getting the impression from the article that they are proposing to use this technique to build semiconductor *components* such as standalone transistors, diodes, etc., etc.
That seems much more feasible than what is implied by the title of this post.

They aren't really proposing much of anything. They are a bit like the guys working on GaAs and InP in the 1980s... once they got two transistors working on a single substrate they exclaimed "This will revolutionize microprocessors!". It didn't.

Standalone components are SOOOO cheap for the most part now, I wonder how they can possibly be displaced.

Possibly useful, but not for logic devices (5, Insightful)

Yarhj (1305397) | about a year and a half ago | (#42125175)

This article wins today's coveted "Most Hyperbolic Headline" award. First off, here's the actual link, for those of you with access to Nature: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11652.html [nature.com]

To understand what the big deal is here, compare baking cookies in your house to a fancy industrial setup: In your home oven you can bake around 20 cookies at once, and you have to put them on a tray. Meanwhile, an industrial bakery has one of those fancy conveyor belt ovens -- dough goes in one side, cookies come out the other, and the conveyor belt itself is the tray. The conventional fabrication process for metallic nanostructures is more like the home method -- you need a tray (usually a silicon substrate, because those are pretty cheap and extremely high-quality), and an reactor of some sort (in this case a really fancy oven that costs more than your car, but still an oven), and you won't be getting any nanowidgets until the kitchen timer dings.

What this will NOT be useful for is logic circuitry. This group has managed to come up with a pretty good method of manufacturing metallic nanorods. That's all well and good, but bear in mind that all of these high quality nanorods are not attached to anything, and not particularly useful in and of themselves. Perhaps they can make individual nanorods into diodes, but even if they do they're still left with essentially a disordered heap of unconnected devices -- try throwing ten toothpicks in the air and having them land in a perfect grid. Now do it for a billion tiny transistors. You may notice that this process does not scale well.

This manufacturing method might actually be more useful in the realm of optics. The real breakthrough here is the fact that high quality metallic nanostructures can be grown without a substrate, and can be grown quickly and continuously. Metallic spheres and rods are actually quite interesting at the nanoscale, and behave in very counterintuitive ways (for instance, suspensions of gold spheres take on very different colors when viewed with reflected vs. transmitted light (See for instance the Lycurgus cup: http://en.wikipedia.org/wiki/Lycurgus_Cup [wikipedia.org] ). People are working away on using those properties to do something more useful than making a better shot glass (for instance, nanostructured metals show some promise at enhancing the efficiency of solar cells), and maybe this manufacturing method will help them out by bringing the cost of high quality research materials down.

Then again, maybe all we'll get is a few overblown press releases and another three weeks of this article on the front page at Slashdot.

Re:Possibly useful, but not for logic devices (1)

Yarhj (1305397) | about a year and a half ago | (#42126381)

Replying to myself with a few clarifications because previewing my post three times is clearly not enough.

0. I forgot a sentence somehow. After the second paragraph, imagine I said "Conversely, the new method is like the industrial bakery -- there's a constant stream of nanowires being manufactured at high speed, and you don't have to wait for an oven to cool down, remove your wafers full of nanowires, then wait for the oven to heat all the way back up before starting another batch.

1. For some reason I decided that the nanowires reported here were metallic -- they are actually III-V semiconductors. Most of what I wrote above still applies, though to get the same plasmonic properties of metallic nanostructures you'd have to dope the nanowires pretty heavily (and even then you'd just wish you were using a metal). Semiconducting nanowires also have interesting optical properties, so if you're not interested in the details you can get away with just doing s/metallic/semiconducting/ on my post.

In more detail, though both metallic and semiconducting nanowires have abnormal optical properties, the mechanisms are different - semiconducting nanowires have very sharp jumps in their absorption spectra due to quantum mechanical confinement (in short: electrons in the structure can only take on certain energy values, so only photons of a particular energy can be absorbed. That's not entirely true, of course, because the electrons in nanowires aren't actually confined in every direction so the absorption features get spread out), whereas metallic nanorods have weird absorption, reflection, and transmission due to the coupling of the electric fields of incident photons to the electrons on the surface of the metal. You can still get plasmonic effects from semiconductors, but they're generally much weaker as the free electron concentration is just that much lower.

Re:Possibly useful, but not for logic devices (0)

Anonymous Coward | about a year and a half ago | (#42161993)

Note that the nanostructure your are talking about is a gold sphere with a single crystal of GaAs nanowire grown out of it. It is a metal/semiconductor hybrid structure.

More porn, stat (0)

Anonymous Coward | about a year and a half ago | (#42126747)

Anything that makes Internet porn viewing cheaper is OK by me.

OK, now how do I wire it to my board? (1)

moeinvt (851793) | about a year and a half ago | (#42130531)

Does my board need to be suspended in a vacuum chamber with a free floating gas substrate so that I can connect this to the rest of the parts?

Obligator (0)

Anonymous Coward | about a year and a half ago | (#42131285)

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