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Ultra-Thin Alternative To Silicon

Posted by Soulskill on from the delicious-thin-mint-technology dept.

An anonymous reader writes "There's good news in the search for the next generation of semiconductors. Researchers with the Lawrence Berkeley National Laboratory and UC Berkeley have successfully integrated ultra-thin layers of the semiconductor indium arsenide onto a silicon substrate to create a nanoscale transistor with excellent electronic properties (abstract). A member of the III–V family of semiconductors, indium arsenide offers several advantages as an alternative to silicon, including superior electron mobility and velocity, which makes it an outstanding candidate for future high-speed, low-power electronic devices."

22 of 83 comments (clear)

  1. Arsenic compounds by Formalin · · Score: 2, Interesting

    I know there is already arsenic compounds in other devices (Some LED colours, GaAs based FETs, etc)

    LED's aren't such an issue, because even when you kill them they usually stay contained within their epoxy. IC's and transistors on the other hand like to explode violently on occasion.

    Just curious about the health hazards, if any apply. I've been known to kill some silicon on occasion ;-)

    Sounds interesting anyway.

    1. Re:Arsenic compounds by dbIII · · Score: 3, Informative

      I'd say a lot safer than that green wood you see in playground equipment that has been treated with an arsenic compound to stop termites from eating it (and that stuff has been tested a lot because some kid somewhere is going to chew it). If we are going to be irrationally scared of elements then Teflon would scare the crap out of everyone.
      The answer as usual is how the stuff will behave with any bit of your body that it is likely to come in contact with and that decides what sort of hazard it is. For instance reactive stuff is an obvious hazard and things that will get into your lungs and never get out or break down another. This stuff is going to have very strong covalent bonds that stomach acid isn't going to touch.
      Oddly enough someone at the University I was working at in 1998 made a very thin diode junction of a very similar material using chemical vapour deposition and he wasn't the first to do so. Making a thin layer of the stuff is relatively easy, making an isolated very tiny transistor is hard.

    2. Re:Arsenic compounds by tom17 · · Score: 2, Informative

      Yes, and Arsenic. It's CCA (Chromated Copper Arsenate)

      However, this is being phased out for Alkaline Copper Quaternary or Copper Azole. In the EU, CCA is no longer allowed for domestic or residential applications. It's also being used more in north america now too.

    3. Re:Arsenic compounds by ChrisMaple · · Score: 2, Informative

      As of about 4 years ago, the formulation for copper-based wood preservatives was changed to eliminate arsenic; the arsenic compounds becoming illegal for residential use in the United States. New compounds are copper azide and other copper-organics.

      --
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  2. Four words why this is useless. by the_raptor · · Score: 4, Informative

    Restriction of Hazardous Substances.

    There are already a bunch of non-substitutable components that can't be used because of RoHS. Adding arsenic to make faster electronics is just not going to fly (it doesn't matter if current methods are just as toxic, everyone knows about Arsenic and RoHS is half PR). Researchers should be concentrating on making electronics less toxic so we don't keep poisoning African and Asian kids (working for electronics "recyclers") with last years iPhones.

    --

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    CINC, 4th Penguin Legion
    1. Re:Four words why this is useless. by Dr.+Spork · · Score: 4, Insightful

      We're talking about a 10nm layer across the surface of a chip - that's about a square centimeter. If anyone seriously complains about 50% of this being Arsenic, I would happily scrape it off and eat it in front of them. I don't think it would be a quantity large enough for the human eye to see.

    2. Re:Four words why this is useless. by bertok · · Score: 4, Informative

      That's just under 3 micrograms of arsenic. According to our trusted interwebs source, wikipedia: "The acute minimal lethal dose of arsenic in adults is estimated to be 70 to 200 mg". In other words, each chip contains about 1/25,000th of the lethal dose, in a non-soluble form.

      I'll think you'll be fine.

    3. Re:Four words why this is useless. by BradleyUffner · · Score: 3, Funny

      multiplied by millions or billions of chips. k.

      He's only going to eat one... How many do you think the average person is going to eat?

    4. Re:Four words why this is useless. by Graff · · Score: 3, Interesting

      multiplied by millions or billions of chips. k.

      Spread out over 149 million square kilometers. At a billion chips that comes out to be less than 7 chips per square kilometer. As someone else pointed out, it's about 3 micrograms of arsenic per chip for a total of about 20 micrograms per square kilometer.

      Yes, there can be higher concentrations in places like trash dumps but it's still going to take a gigantic amount of these chips in one spot before anyone would have any reasonable concerns about the environmental impact due to the arsenic levels.

      Somehow I think we'll be just fine...

      --
      Sapere aude!
    5. Re:Four words why this is useless. by tulcod · · Score: 2, Insightful

      And even if RoHS would not be an issue, this is not the stuff that will magically make future CPUs faster. The performance bottleneck of integrated circuits is (usually) wire delays. See, signals get sent from one transistor to another using aluminium wires. Those aluminium wires have a bit of resistance, and a bit of capacitance with other wires and the silicon substrate. Heck, more often than not they have so much capacitance with other wires that they get rerouted to avoid signal interference. So if all wires act like (very small) capacitors, and they all have (a tiny bit of) resistance, it takes some time (think sub-nanoseconds here) to build up charge on the other side of a wire, and that is what causes the biggest delays. Routing all wires as efficiently as possible is a research area in itself.

    6. Re:Four words why this is useless. by Muad'Dave · · Score: 2, Funny

      Hungary: Toxic red sludge has reached the [Blue] Danube

      So now we have the Purple Danube? Is Prince performing it?

      --
      Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  3. Re:But we are already running out of Indium... by aramosfet · · Score: 3, Insightful

    I hate it when people post links to articles which require me to login or subscribe to read. Could you atleast tell me whats the "single material" he's talking about?

  4. Re:But we are already running out of Indium... by Dr.+Spork · · Score: 2, Insightful

    Yeah, but if we need layers of about 10nm, I'm quite sure we have enough Indium to make a cpu that's larger than the entire surface of the Earth.

  5. Why thin? by DriedClexler · · Score: 4, Funny

    I thought the purpose of silicone was to make the tits look *thicker*?

    --
    Information theory is life. The rest is just the KL divergence.
    1. Re:Why thin? by the_other_chewey · · Score: 4, Insightful

      silicon != silicone, dammit.

  6. Ultra-Thin Alternative to Silicone - FINALLY by commodoresloat · · Score: 2, Interesting

    This day has been a long time in coming. I'd like to congratulate everyone involved. Younger folks may not realize how important this news is. Thanks to this we FINALLY have a slashdot headline where "Natalie Portman" is actually on topic.

  7. Re:But we are already running out of Indium... by Tumbleweed · · Score: 2, Funny

    Yeah, but if we need layers of about 10nm, I'm quite sure we have enough Indium to make a cpu that's larger than the entire surface of the Earth.

    Wow. With a CPU that big, we'd have enough computational ability to figure out what the question of 'Life, the Universe and Everything' is. We should be able to speed that up, since we can work backwards from the answer. That'd be spiffy.

    Maybe we could run the Hurd on it, too.

  8. About time by Khyber · · Score: 2, Insightful

    I thought this possible a year or so ago while goofing off with diodes, but imagined the method needed to prevent leakage from the alloy would be too difficult to implement on a small scale.

    Glad to see I could be wrong. Science never ceases to amaze and educate me every single day.

    --
    Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
  9. Re:Dumb Question by Raptoer · · Score: 2, Informative

    Put simply, the way a transistor works requires the use of semiconductors. It's a property other than resistance which the transistor requires. When not in a transistor, materials with a high conductivity are used.

  10. Why Bother? by Plekto · · Score: 2, Interesting

    I don't see the point of this when comparing the potential of Graphene based processors. These things, when (not if) they become reality, will have the same impact that perfecting Fusion power will. There's just no reason to spend the time trying to eek out a few more percent when the second that we manage to get the better technology to work, we'll no longer need anything else.

    1. Re:Why Bother? by the_pooh_experience · · Score: 2, Informative

      Because it is possible and demonstratable to grow InAs today. It is grown in bulk, single crystal material. Graphene, while making strides in the "manufacturable" direction, is still practically relegated to grad students shaving pencils with razors onto tape to get a single monolayer film.

  11. That's incredibly naiive by tygerstripes · · Score: 3, Insightful

    If this process is simpler and quicker to reach the fabs, and produces a notable performance increase, then it's worth it to develop. Someone will want to buy it, and that means someone will want to develop it.

    Just to hammer it home: why do you bother, ever, to upgrade your hardware, knowing it'll one day be obsolete?

    --
    Meta will eat itself