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Molybdenite As an Alternative To Silicon

timothy posted more than 3 years ago | from the mind-the-gap-sir dept.

Science 169

An anonymous reader writes "Molybdenite (MoS2) can be used to make transistors that consume 100,000 times less energy in standby state. This mineral, which is abundant in nature, is often used as an element in steel alloys or as an additive in lubricants. Research carried out in Switzerland at the Ecole Polytechnique Fédérale de Lausanne's Laboratory of Nanoscale Electronics and Structures (LANES) has revealed that is a very effective semiconductor. Molybdenite's 1.8 electron-volt gap is ideal for transistors and gives it an advantage over graphene (which does not have a gap)."

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Sounds like they are... (-1)

Anonymous Coward | more than 3 years ago | (#35053318)

"Flogging Molly"

Molykote? (4, Interesting)

cvtan (752695) | more than 3 years ago | (#35053330)

Isn't this just Moly disulphide, the lubricant in Molykote? http://www.dowcorning.com/content/molykote/anniversary.aspx?bhcp=1 [dowcorning.com]

Re:Molykote? (2)

macraig (621737) | more than 3 years ago | (#35053422)

Already asked and answered in TFS. What's your point, aside from giving Dow free advertising?

Re:Molykote? (1)

cvtan (752695) | more than 2 years ago | (#35055214)

Point is: Keyboard can be used without engaging brain first and it was past my bedtime. Never heard of any device physics work on moly disulphide even after being in the business for 30 years. All we hear about is how Gallium Arsenide is the material of the future. Glad some people are still being clever. Native oxide on Silicon is still a big advantage though. Molykote is good stuff; no problem giving free advert to Dow. Plus if people want to connect with the material, they can just go buy some to get a hands on feeling (but don't get it on your hands or clothes). A bit easier than getting a chunk of GaAs or InSb to play with.

Re:Molykote? (3, Informative)

pwagland (472537) | more than 3 years ago | (#35053434)

Isn't this just Moly disulphide, the lubricant in Molykote? http://www.dowcorning.com/content/molykote/anniversary.aspx?bhcp=1 [dowcorning.com]

Possibly, from the article:

This mineral, which is abundant in nature, is often used as an element in steel alloys or as an additive in lubricants. But it had not yet been extensively studied for use in electronics.

That is this material has been known about for quite some time, however it's applications to electronics are only now being investigated, and he initial results appear to be quite favourable.

Re:Molykote? (-1)

Anonymous Coward | more than 3 years ago | (#35053502)

The apostrophe has been known about for quite some time, however its application in the English language is something you can investigate.

Re:Molykote? (-1)

Anonymous Coward | more than 3 years ago | (#35053564)

The apostrophe has been known about for quite some time; however, its application in the English language is something you can investigate.

Re:Molykote? (1)

ocdscouter (1922930) | more than 3 years ago | (#35053636)

The identity has been known about for quite some time; however, its application in discussion and debate is something you can investigate.

Re:Molykote? (0)

Anonymous Coward | more than 2 years ago | (#35053754)

The penis has been known about for some time; however.. wait darling, it's working again! I'll be right up!

Re:Molykote? (1, Funny)

BluBrick (1924) | more than 2 years ago | (#35053860)

The horse is known to have been been dead for some time; however its continued flogging is something you can investigate.

Re:Molykote? (0)

maxwell demon (590494) | more than 2 years ago | (#35054040)

I 'sugge'st to put apo'strophe's in front of all 's. It make's a more intere'sting read. :-)

Re:Molykote? (1)

davester666 (731373) | more than 2 years ago | (#35054154)

I assume this product will be treated the same as in the drug industry, so it can be re-patented for the new use, thus extending the patent for the compound for both uses, or does this techique only apply to the drug industry?

Re:Molykote? (1)

wb5bbw (143967) | more than 3 years ago | (#35053452)

If so, that's a very slick solution for semiconductor fabs....

Re:Molykote? (1)

c0lo (1497653) | more than 3 years ago | (#35053556)

Yes, it is. The good news: unlike silicone, you can buy some of it and make your own transistors... errr... isn't it?

Re:Molykote? (5, Interesting)

arivanov (12034) | more than 2 years ago | (#35054082)

Probably not pure enough.

You need 99.995+% purity for most semiconductor stuff (99.999+ for CPUs and memory) which can be achieved only via zone smelting. In order to zone smelt the material needs to be able to re-crystalize after being heated locally in the first place. If it does not you can forget using it as a production semiconductor. There are in fact plenty of materials out there which have electron gaps are more "interesting" than silicon. We just have not figured out how to grow to purify them in quantity.

As far as MoS2 is concerned it does not melt and does not recrystalize (it decomposes straight away) so zone smelting is not an option. It decomposes straight away. So frankly I do not see how you can achieve 99.99+ purity to do anything useful with it.

Re:Molykote? (1)

c0lo (1497653) | more than 2 years ago | (#35054162)

So frankly I do not see how you can achieve 99.99+ purity to do anything useful with it.

My bad: next time I'll explicitly put a *wink*.

Re:Molykote? (1)

adamchou (993073) | more than 3 years ago | (#35053688)

so... what you're saying is my motherboard can now double as lube...

Re:Molykote? (1, Funny)

Anonymous Coward | more than 2 years ago | (#35053814)

This won't help you get laid.

reduction in subthreshold leakage current (4, Interesting)

RichMan (8097) | more than 3 years ago | (#35053344)

In the latest technologies a lot of current is wasted to subthreshold conduction [wikipedia.org] . Current that flows then the transistors should be "off".

A material with a higher bandgap 1.8ev to silicons 1.1ev will naturally have less leakage. As it is an exponential thing the leakage should not just be a reduction of 1.1 to 1.8 thing but much more significant.

Re:reduction in subthreshold leakage current (0)

Anonymous Coward | more than 3 years ago | (#35053576)

For those of us who don't know, what is this gap that's referred to in the summary?

Re:reduction in subthreshold leakage current (0, Troll)

NEDHead (1651195) | more than 3 years ago | (#35053618)

That would be the gap between those who read /. to be cool, and those who actually understand some of what is discussed

Re:reduction in subthreshold leakage current (3, Insightful)

MagusSlurpy (592575) | more than 2 years ago | (#35053924)

That would be the band gap. [wikipedia.org]

Re:reduction in subthreshold leakage current (3, Informative)

GospelHead821 (466923) | more than 2 years ago | (#35055102)

In insulators, there are no energy states that involve conductive electrons. In conductors, all of the energy states involve conductive electrons. In semiconductors, electrons normally reside in a nonconductive state but you can inject some energy and the electrons will be raised to a conductive state. The amount of energy required to raise the electrons to a conductive state is that semiconductor's gap.

Re:reduction in subthreshold leakage current (1)

gstrickler (920733) | more than 3 years ago | (#35053588)

Sounds promising:

Advantages:

  • Higher melting point than silicon
  • Low thermal expansion
  • Low leakage
  • Allows extremely thin layers.
  • US, Canada, Chile, Peru, and China have sizable deposits.

Disadvantages:

  • Expensive
  • Relatively rare
  • Natural deposits contain traces of radioactive rhenium-187

Re:reduction in subthreshold leakage current (0)

Anonymous Coward | more than 3 years ago | (#35053724)

However, it will require more electrons to break the bandgap. Given a high enough switching speed, this might actually INCREASE the total electric current.

not at small scale (1)

gr8_phk (621180) | more than 2 years ago | (#35055226)

Leakage current has been the dominant issue since the days of the P4 and the first nVidia vacuum cleaner. As the devices have gotten smaller, the leakage has gone up significantly. To combat this, they've stopped increasing clock speed and started to use a lot of clock-gating and power gating where parts of the chip are inactive or even turned off. They are at the point where a higher gate voltage to turn on should not offset the reduced power dissipation due to leakage current.

Make better computers, kill more plants (1, Interesting)

Khyber (864651) | more than 3 years ago | (#35053348)

Molybdenum is a CRITICAL trace element in the development of any food crop we have.

This reeks of the dumbest thing one could do, EVER.

Re:Make better computers, kill more plants (4, Insightful)

Shihar (153932) | more than 3 years ago | (#35053366)

I'll keep that in mind before I strip mine any farms for molybdenum. Otherwise, I am pretty sure the plants inside of the middle of a mountain are not going to mind.

Re:Make better computers, kill more plants (-1, Troll)

macraig (621737) | more than 3 years ago | (#35053460)

I am pretty sure the plants inside of the middle of a mountain are not going to mind.

You made fun of him for being overly simplistic (he wasn't, just poorly documented), but then you turned around and committed the same crime of ignorance. Remind me to pass on watching your TED talk.

Re:Make better computers, kill more plants (3, Insightful)

Shihar (153932) | more than 2 years ago | (#35053832)

Um, okay. You can pass on my TED talks. Otherwise, the point stands.

Molybdenum is generally gathered as a byproduct of other mining operations. The "free" molybdenum in soil that plants uses is utterly unaffected when you tear open a mountain to get at it. The original point of "OMG BUT PLANTS USE IT!" was dumb and reactionary. Hell, just re-read the original post if you are in doubt. This is like if someone declared that they found a novel use for nitrogen and someone else freaked out be cause OMFG nitrogen is critical for all life!!!11!!

There are actual legitimate road blocks to using molybdenum in place of silicon. OMFG the plants!11!!! isn't one of them.

Re:Make better computers, kill more plants (1, Interesting)

Khyber (864651) | more than 2 years ago | (#35053982)

"There are actual legitimate road blocks to using molybdenum in place of silicon. OMFG the plants!11!!! isn't one of them."

Okay, you tell that to a HUGE hydroponics industry responsible for keeping YOU fed by producing the food you buy.

They need that molybdenum WAY more than you do.

We also need that molybdenum for other things, like medical agents.

Oh, wait, those medical agents tend to come from PLANTS.

I have futures in all kinds of elements, from molybdenum to iridium. Why not use something with a higher band gap to reduce the current leakage any further? You've got TONS of other materials that are better suited (and I can think of several off the bat from my own experience in the optoelectronics industry workign alongside Cree and Nichia.)

I don't think you're even close enough to having the relevant experience to be able to talk, sir. Come back when you're actually fabricating semiconductors, okay?

Re:Make better computers, kill more plants (1)

gilleain (1310105) | more than 2 years ago | (#35055224)

I have futures in all kinds of elements, from molybdenum to iridium....I don't think you're even close enough to having the relevant experience to be able to talk, sir. Come back when you're actually fabricating semiconductors, okay?

Because buying futures in metals is exactly the same as being a chip manufacturer....

Although unfair comment, you are the guy that claimed to need a more precise quadratic equation in order to make your LED lights for growing pot, so I'm not particularly sorry.

Re:Make better computers, kill more plants (1)

macraig (621737) | more than 2 years ago | (#35054160)

There might not be any immediate consequences to mining molybdenum in vast quantities, but you're thinking is short-sighted. What we're talking about here tantamount to SEQUESTERING molybdenum out of the environment... where plants can't get at it through natural processes like erosion. Never heard of erosion? It may not affect plants for a millennium, but what doesn't GO around doesn't COME around. This is a finite and closed ecosystem. That was the point of the GP. We're doing the same with many elements, not just molybdenum, and even doing it by the simple act of static farming - continually removing biomass from the same spot - in the first place. It's called soil depletion. Crop plants today don't have the same micro-nutrient value as the same crops 50 years ago; this has been demonstrated.

We'd be better off grabbing it from the Moon, assuming it's present in quantity.

Re:Make better computers, kill more plants (1)

muridae (966931) | more than 2 years ago | (#35054254)

Yes, we are sequestering it. We are storing it so efficiently that there is no chance of it or any other material used in these circuits ever leaching back into the environment in a landfill. It is such a closed system that in a millennium there will be no molybdenum left, it will all have leaked out into these chips. And even if could seep out of these chips, everyone uses their electronics for 100 years or more, none of them are ever disposed of.

Please, for the love of everything you hold holy, don't give green geeks a bad name. Yes, this mineral is very useful for hydroponics as has been pointed out, but that use can exist side-by-side with it's use in electronics. Hell, if it's use in electronics makes them potentially more recyclable, that would be a great improvement. But that idea that we are going to destroy this element, by moving it from one place to another inside a closed system, is absurd.

I will admit ignorance, is there something about these moly circuits that actually does sequester it in a form that plant-life is proven to be unable to use? Something about applying the common mineral form of it over another common mineral will make it as toxic as polonium? Yes, the epoxy shells that ICs are housed in is a problem, but that's something that demands it's own rational arguments and solutions. Does mixing it onto silicon make it impossible to retrieve later? Is all of this some how infinitely more disastrous than it's use as a lubricant?

Re:Make better computers, kill more plants (1)

germansausage (682057) | more than 3 years ago | (#35053410)

Why exactly is making MoS2 devices the dumbest thing one could do, EVER?

Re:Make better computers, kill more plants (5, Insightful)

Mr Z (6791) | more than 3 years ago | (#35053464)

Huh? Just like all the steel we produce somehow reduces the amount of iron plants and animals can make use of? Are you suggesting that a significant fraction of mined molybdenite goes to fertilizer manufacture?

Molybdenum may not be as abundant as silicon, but it's still fairly abundant. (54th most abundant in the crust and 25th most abundant in sea water, says Wikipedia.) And given its fairly high cost, I imagine any increased demand will be offset by its cost. This would limit molybdenum to niche applications where controlling leakage is a must. I imagine MoS2 based semiconductors would only be cost effective if they can figure out how to use as little of it as possible, perhaps with MoS2 over some other substrate.

I can think of much stupider things that we could do (and in fact are doing already), such as bottling water, or hyperfocusing food production on corn and subsidizing large quantities of corn-based ethanol production.

Re:Make better computers, kill more plants (2)

Mr Z (6791) | more than 3 years ago | (#35053504)

And actually, it appears that MoS2 over a silicon substrate is exactly what they're proposing. [eurekalert.org] I knew I should have looked at the blowup first.

Re:Make better computers, kill more plants (1)

The Hatchet (1766306) | more than 3 years ago | (#35053524)

I might add, if you read the article, you would see that it is indeed Molybdenum disulfide on a silicon substrate.

Re:Make better computers, kill more plants (1)

Mr Z (6791) | more than 3 years ago | (#35053546)

Yeah, I missed that. I didn't see it in the article body, but it was obvious when I finally clicked on the image at the right so all the labels were readable.

Re:Make better computers, kill more plants (1)

Kjella (173770) | more than 3 years ago | (#35053674)

I imagine MoS2 based semiconductors would only be cost effective if they can figure out how to use as little of it as possible, perhaps with MoS2 over some other substrate.

Near as I can tell it's dirt cheap. I figure the cost will be the same as current processors, getting it to ultra-pure quality and the etching process. You can get a kilo of not-so-very-pure MoS2 for about a buck [dhgate.com] . Even silicon good enough to make solar cells costs $67 dollars a kilo [greentechmedia.com] according to this 2009 article. The rest is for turning it from a lump of metal to a working processor.

Re:Make better computers, kill more plants (1)

Mr Z (6791) | more than 2 years ago | (#35053762)

Well, according to Wikipedia, pure molybdenum was going for $30,000 a tonne in August 2009 [wikimedia.org] and before that had shot up to $100,000 a tonne for several years. (That works out to $30 / kilo and $100 / kilo respectively.) I based my cost statement on the higher number on the basis that MoS2 semiconductors would increase the demand.

I guess that cost puts it on a par with silicon for bulk material cost. More expensive potentially, but not orders of magnitude more like I was thinking. The rest comes, as you say, from the processing required to turn it into a working processor. Since they're putting it into etched features on a SiO2 substrate, what sort of process are they using to get it there? I guess that's where the money maker is for this process.

Re:Make better computers, kill more plants (1)

Kjella (173770) | more than 2 years ago | (#35053948)

I based my cost statement on the higher number on the basis that MoS2 semiconductors would increase the demand.

Maybe, but that also depends on economics of scale. If it's more of a specialty product today it might go down with volume, unless you run into resource limitations.

Re:Make better computers, kill more plants (1)

Mr Z (6791) | more than 2 years ago | (#35054056)

The spot price of molybdenum was over twice its current price for around 5 years (from ~2004 - 2009). [infomine.com] Given that the drop coincided with the recent economic meltdown, it doesn't seem like a huge leap to suggest that that drop is a direct result of reduced demand

The steep swing suggests that the annual production of molybdenum is fairly fixed (rather inelastic), at least for the time being. This suggests to me that you would probably have to find new mines or new extraction techniques (say from seawater?) to make the supply of molybdenum more elastic, and thus reduce the slope of the supply curve.

Re:Make better computers, kill more plants (1)

Lonewolf666 (259450) | more than 2 years ago | (#35054858)

The image you linked to a few posts back suggests that the amount of MoS2 going into each transistor would be very small.
It shows a molybdenite layer with
width = source-drain distance. I guess we're talking millimeters for a big power transistor here, some 10 nanometers for transistors in a CPU.
thickness = distance between SiO2 substrate and gate. I guess we're talking micrometers for a power transistor here, less for transistors in a CPU.
and length = whatever gate length the transistor has.

Overall, we might end up needing a few milligrams per CPU or power transistor. Losses in the process included. The price of raw molybdenum should have not much of an influence there.

Re:Make better computers, kill more plants (1)

Mr Z (6791) | more than 2 years ago | (#35054078)

Ok, so I googled around and found this interesting report. [roskill.com] It seems that molybdenum production has more or less kept pace with demand. It appears that the price remained high because demand was leading supply slightly. When demand fell behind supply, the price tanked.

The report has more detailed insights. Enjoy!

Re:Make better computers, kill more plants (1)

PPH (736903) | more than 3 years ago | (#35053746)

Do you really think that making microprocessors with a thin film of MoS2 is going to increase the global demand for the substance beyond that already used for lubricants?

Re:Make better computers, kill more plants (1)

nusuth (520833) | more than 2 years ago | (#35055212)

Lubricant use is pretty niche too; 80% of molybdenum is used in making steel and iron alloys. Granted, that figure includes non-MoS2 use, but electronics industry will probably start synthesis from pure Mo instead of purifying products of existing MoS2 plants.

Re:Make better computers, kill more plants (1)

The Master Control P (655590) | more than 3 years ago | (#35053470)

I'll tell the mining companies to keep that in mind before they turn every atom of Molybdenum in earth's crust over to the semiconductor fabs. Also, I'll ask them not to grind up old chips and dust crops with them. We good?

funny (0)

Anonymous Coward | more than 3 years ago | (#35053484)

as if computers don't end up in a landfill after 18 months.

Re:Make better computers, kill more plants (0)

Anonymous Coward | more than 3 years ago | (#35053514)

Better than using up all the sand on our beaches. Also, it is a trace element. A strip mine in a mountain in the right place could easily produce gigatons of this shit. Plus, I honestly don't think plants will mind that we are using naturally occurring molybdenum disulfide, when most plants use pure molybdenum found in the ground, considering both are prevalent and naturally occurring. Put that in your pipe and smoke it.

Re:Make better computers, kill more plants (1)

Khyber (864651) | more than 2 years ago | (#35053988)

"when most plants use pure molybdenum found in the ground"

Actually, no, molybdenum disulphide is more bioavailable than pure molybdenum to a plant.

Where'd you get your biology degree from?

Re:Make better computers, kill more plants (1)

WillKemp (1338605) | more than 2 years ago | (#35053792)

Don't worry, we're probably going to run out of phosphorous before we run out of molybdenum - and plants are quite partial to that, too.

Let me just say (0)

The Hatchet (1766306) | more than 3 years ago | (#35053472)

Fuck Yea.

Lets totally get this ball rolling, and replace as many current devices and server farms as possible. So many people advocate cleaner energy solutions, but neglect the possibility of ridiculously increased efficiency. I say, if we can make retarded huge increases in efficiency, we can significantly reduce our power consumption. Plus, can you image a goddamn smart phone with a week long battery life?? Or a laptop that runs for days without needing to recharge? A server farm that could be powered by solar power and a few large battery power storage units? Plus, how much less cooling will be required with such an efficient system. We could all afford to power smart dwellings, and increase our use of technology in our everyday lives.

So like I said: Fuck Yea.

Re:Let me just say (1)

amRadioHed (463061) | more than 3 years ago | (#35053506)

You want to save energy by replacing as many of the the currently installed systems in the world? Why do I get the feeling that trashing perfectly good equipment, and manufacturing replacements is not the best use of our energy resources.

Re:Let me just say (2)

x0ra (1249540) | more than 3 years ago | (#35053516)

in reality, you will just get more features out of the same die consuming the same amount of power than today. We did great with small CPU, the software we run on them just became full of bloat (not to speak about all the HD crap). That said, Intel's business is to sell you a new CPU every few years, not make it last 15 years.

Re:Let me just say (1, Informative)

Belial6 (794905) | more than 2 years ago | (#35054038)

That was true up to a point. Over the last 5 or so years, we hit the 'good enough' point on computers. Power efficiency is where it is at now. With the last round of upgrades in my home, I went from an average power usage of 180kw on my computers to an average of 40kw. That doesn't even include the fact that most of my computers can actually go into stand by now.

Re:Let me just say (1)

Kjella (173770) | more than 2 years ago | (#35054432)

Unless we create a magic battery, power consumption will always be a huge thing for laptops and cell phones. Data centers too certainly measure performance/watt. But I agree, for the regular desktop it's no longer a big deal, if it ever was.

Re:Let me just say (3, Informative)

Gaygirlie (1657131) | more than 3 years ago | (#35053612)

Plus, can you image a goddamn smart phone with a week long battery life?? Or a laptop that runs for days without needing to recharge? A server farm that could be powered by solar power and a few large battery power storage units?

You have misunderstood the article. It clearly says molybdenite transistors consume 100.000 times less energy than silicon ones in STANDBY. Not when operational. Sure, it would increase efficiency of mobile devices where you turn unneeded transistors off to save energy, but it would do nothing for when the system is operational and in use. Thus your idea of a server farm being solar powered is completely without basis.

Molybdenite's strength is in mobile applications: when the device is in standby mode it consumes a lot less energy than traditional silicon-based ones. But it has another strength here: silicon is a 3-layer material, whereas molybdenite is monolayer. This means that you can make smaller chips, or cram more stuff in a chip of the same size.

Re:Let me just say (3, Insightful)

MadnessASAP (1052274) | more than 2 years ago | (#35053854)

You're doing some freaky ass computing if all the transistors in your CPU are active at the same time.

Re:Let me just say (1)

pantherace (165052) | more than 2 years ago | (#35053872)

Actually, I could see a use for it, if it can be deposited in parts of a silicon chip: Cutting power to parts of the chip.

Though there are a lot of problems with the few solutions I've come up with in about 2 minutes of reading this. Mostly involving using different materials on the wafer, but if it is that much more efficient, I could see the relatively expensive process of cutting a few parts to be replaced with this out with lasers eventually panning out.

Then again, most of the actual silicon I've looked at personally with any degree of knowledge was 1980s/early 1990s level stuff. Now they are more or less black boxes described by whitepapers.

Oh dear (2)

Tideflat (1858480) | more than 3 years ago | (#35053492)

Oh dear. This means they might have to rename Silicon Valley to Molybdenite Valley, but that doesn't sound nearly as nice.

Re:Oh dear (1)

ColdWetDog (752185) | more than 3 years ago | (#35053508)

Oh dear. This means they might have to rename Silicon Valley to Molybdenite Valley, but that doesn't sound nearly as nice.

Valley of the Molls?

Re:Oh dear (0)

Anonymous Coward | more than 3 years ago | (#35053752)

Filled with Molybdenizens?

Re:Oh dear (0)

Anonymous Coward | more than 2 years ago | (#35053932)

MolyValley does have a ring to it

Molly's Revenge (1)

billstewart (78916) | more than 2 years ago | (#35054034)

Molly's Revenge [mollysrevenge.com] are one of the local Irish bands seen here in the Bay Area. (Apparently they were a follow-on to an earlier band called Dance Around Molly, but with a name like "Molly's Revenge" they eventually had to wrote a song involving someone named Molly and some revenge...)

Re:Oh dear (0)

Anonymous Coward | more than 2 years ago | (#35054366)

Oh dear. This means they might have to rename Silicon Valley to Molybdenite Valley, but that doesn't sound nearly as nice.

Don't worry -- they'll soon molyfy anyone who's upset.

finding a good material is not the problem (4, Interesting)

Goldsmith (561202) | more than 3 years ago | (#35053494)

There are plenty of materials out there that make good semiconductors, the question is: can we make them?

Moly disulfide is a material a couple of different graphene groups have been looking at (hey, we know there's an issue with graphene). What this paper really means is that the Ecole group has figured out how to *make* MoS2 better than other people, and that's really the hard part. Of course, they're still making devices using scotch tape exfoliation...

It's really hard to mass produce 2D materials.

Re:finding a good material is not the problem (0)

Anonymous Coward | more than 2 years ago | (#35053782)

Also, with a field effect transistor, the massive use comes from the simplicity in abundance, doping AND in making an insulating layer. For silicon, the process is: expose the crystal to air/oxygen...DONE. Many of these exotic semiconductors don't have a way to easily add the required, extremely thin, insulating layers.

Re:finding a good material is not the problem (2)

evanspw (872471) | more than 2 years ago | (#35055120)

Sing it, brother! I work in compound semiconductor designing RF chips. I know a lot of silicon guys and very few of them have any clue what makes silicon a damn useful semiconductor (namely, it's oxide). I can't think of another semiconductor that has anything like as nice an oxide as silicon, easy to grow, very effective insulator with decent breakdown. If any of the compound semiconductors had anything like as good a native oxide, there would be no silicon industry (silicon otherwise mediocre electron mobility and band-gap, though ok thermals).

Re:finding a good material is not the problem (0)

Anonymous Coward | more than 2 years ago | (#35053842)

Ecole == School (in French)... the "Ecole group"???

Re:finding a good material is not the problem (0)

Anonymous Coward | more than 2 years ago | (#35054408)

More importantly, other than a slightly wider gap (GaN, ZnO, organics, ...) and that its 2D (so?), what killer advantage does it have to overturn the silicon X trillion of R&D and Y hundred billion of existing plant and kit?

and a baby's arm holding an apple! (0)

Anonymous Coward | more than 3 years ago | (#35053540)

Like I could resist this! What do YOU want from life?

a king-size Titanic unsinkable Molly Brown waterbed with polybendum,
a foolproof plan and an airtight alibi,
real simulated Indian jewelry,
a Gucci shoetree,
a year's supply of antibiotics,
a Las Vegas wedding,
a Mexican divorce,
a solid gold Kama Sutra coffee pot,
or a baby's arm holding an apple?

Re:and a baby's arm holding an apple! (1)

Anne Thwacks (531696) | more than 2 years ago | (#35054492)

I'll take the Mexican divorce, thanks.

Abundant ... hello? (4, Informative)

angel'o'sphere (80593) | more than 3 years ago | (#35053550)

This mineral, which is abundant in nature, is often used as an element in steel alloys or as an additive in lubricants. That is a joke, isn't it? Or is it just /.? From Wikipedia: Molybdenum is the 54th most abundant element in the Earth's crust and the 25th most abundant element in the oceans, with an average of 10 parts per billion; it is the 42nd most abundant element in the Universe. That is not abundant that is pretty rare. Considering 35% of the planet is silicon ... or is it more? Regards, Angel

Re:Abundant ... hello? (2)

KiloByte (825081) | more than 3 years ago | (#35053640)

It is very abundant compared to what is needed for this task, as opposed to some other proposed replacements. It's not like you need tons of molybdenite.

Re:Abundant ... hello? (4, Interesting)

m85476585 (884822) | more than 3 years ago | (#35053704)

How much of that silicon is ultra pure semiconductor grade? Probably none, so both materials need to go through a refining process. If there are areas with high moly concentrations, it doesn't matter how much the rest of the world has, as long as those mines are enough to meet demand (and can continue to do so for a while).

Re:Abundant ... hello? (1)

Anonymous Coward | more than 2 years ago | (#35053800)

It's so rare that tons of "moly" steel and "moly" grease are used yearly in vehicle and heavy machinery because of it's cost effectiveness. Silicon is very difficult to produce in the grade required for electronics and temperamental as hell in the manufacturing process.

Re:Abundant ... hello? (1)

noidentity (188756) | more than 2 years ago | (#35054052)

Yep, the table of abundance of elements in Earth's crust [wikipedia.org] is damning. 27% Si in crust, 0.00015% Mo in crust.

Re:Abundant ... hello? (3, Informative)

Namarrgon (105036) | more than 2 years ago | (#35054372)

That table you linked to says the annual production of molybdenum is 80 kilotonnes, which is not exactly rare.

It also says that the annual production of electronics-grade silicon is only 5 kilotonnes, so our needs aren't going to be a problem.

Re:Abundant ... hello? (4, Insightful)

mcelrath (8027) | more than 2 years ago | (#35054320)

You don't need 10kg of the stuff to make a semiconductor device. Compare it to gold: we produce about 30x more Mo, and you certainly have a few grams of gold somewhere in your house. Anyway my guess is that it might be laid down in layers on top of an insulating substrate (and the substrate doesn't have to be MoS2). So the quantities required are not out of line with production, despite the fact that it is relatively rare in the universe.

I See A Problem with Molybdenite (1)

LifesABeach (234436) | more than 3 years ago | (#35053560)

"...Molybdenite's 1.8 electron-volt gap is ideal for transistors and gives it an advantage over graphene (which does not have a gap)..."

With Graphene, I can scribble it on Scotch Tape [physorg.com] and get a Nobel Prize [wikipedia.org] ; can I do that with Molybdenite?

Can't reduce anything by more than 1X (0)

Anonymous Coward | more than 3 years ago | (#35053608)

It's not possible to reduce anything by more than 1X - because at that point you are left with NOTHING
  - You can reduce power consumption to 1/100,000 of the previous consumption, but not reduce it by 100,000 x.
- this is just a quirk of mathematics that many people either don't realize, or don't understand.

Re:Can't reduce anything by more than 1X (2)

omglolbah (731566) | more than 3 years ago | (#35053716)

It is not a quirk of mathematics. It is a quirk of language.
While it can be parsed the way you say, most would parse it to mean "1/100000 of previous consumption".
It might not be the "right" way, but it is the way most people read it.

So on one hand what you state is correct from a mathematical standpoint but on the other hand irrelevant.
It is technically incorrect but the phrase "xxx times less" has become the way people express that something is 1/xxx of what it used to be.
You can yell at people until you're blue in the face but it is pointless to try to change the language back to what it used to be :p

Re:Can't reduce anything by more than 1X (1)

Kjella (173770) | more than 2 years ago | (#35055008)

More and less are opposites, so is multiplication and division. Most people take ten times more to mean x * 10 and ten times less x / 10. Neither is mathematically correct, but it has a certain logical consistency.

Re:Can't reduce anything by more than 1X (0)

Anonymous Coward | more than 3 years ago | (#35053730)

Evidently you've never been swimming in a very cold lake.

Re:Can't reduce anything by more than 1X (1)

nedlohs (1335013) | more than 2 years ago | (#35053884)

English is not mathematics. And no, the rest of us aren't changing our language to match your obsessive needs for it to be so.

Before you mod me "off-topic"... (0)

unitron (5733) | more than 3 years ago | (#35053624)

...for recommending the movie "The Brothers O'Toole", look it up.

This makes one wonder... (1)

Anonymous Coward | more than 3 years ago | (#35053662)

With all of these other materials available for computer circuitry , are their computers manufactured with materials that are far more efficient but cost more (probably enormously more) to produce that are only available to a select few ?

Re:This makes one wonder... (0)

Anonymous Coward | more than 3 years ago | (#35053738)

I mean... Imagine a cellphone(smartphone) with months of talk time and a far more powerful system bus than what we have now.

Taking a page from Mac (2, Funny)

Anonymous Coward | more than 3 years ago | (#35053678)

Google just announced their new browser update, "Chrome Moly".

great, more advertising by press release (3, Interesting)

cats-paw (34890) | more than 2 years ago | (#35054002)

let me know when you have I-V curves for a moly disulpide FET. Both p and n types please.

I learned many moons ago, that one of the most important things about Si is the fact that it's so easy to grow an oxide. It's EXTREMELY useful when processing integrated circuits. Otherwise everything electronic would use III-V's.

Any new material which aims to replace Si is going to need an equivalent process capability.

Personally I'm hoping for a breakthrough in organic semiconductors. I want to be able to screen print transistors at home.

Re:great, more advertising by press release (3, Insightful)

Ranzear (1082021) | more than 2 years ago | (#35054418)

I don't see moly transistors replacing the entirety of silicon transistor applications in the same way that graphene will never replace silicon.

I can, however, see moly transistors stepping in for the power regulation side of a chip and system where efficiency is demanded, and graphene-based 'burst processing' cores that are shut down completely when not in use on the performance side.

Everything is about application, adaptation, and integration of technologies, not seeking out a replacement for every end of the spectrum at once. Silicon is the Jack in the middle, while the specialists should be looked upon as integrable to the whole of transistor arrangement.

Re:great, more advertising by press release (0)

Anonymous Coward | more than 2 years ago | (#35055218)

"I want to be able to screen print transistors at home."

Whatever the hell for?

New Slashdot (0)

Anonymous Coward | more than 2 years ago | (#35054090)

Well the Einstein picture looks fairly accurate... like it's been dead for years! Why do I have to scroll all the way to the bottom to get more comments? Why does this version of slashdot exist?

I for one... (-1)

CptNerd (455084) | more than 2 years ago | (#35054104)

I for one welcome our new Molybdenite masters...

Shattered hopes of Mass Production (0)

Anonymous Coward | more than 2 years ago | (#35054458)

cant wait to upgrade my laptop
and then I thought of something else that could be upgraded
I had hope that this new molymer(?) might need to be in high demand to drive mass production and reduce prices.
using this alternative to silicone for paired spherical enhancements.
a micro chip would use a very small amount compared to these spheres of 200-500ml each
then i came across this sentence

"One of molybdenite's advantages is that it is less voluminous than silicon, which is a three-dimensional material."

I think this would be a disadvantage, especially with all the 3D monitors.

not a replacement (1)

Gravis Zero (934156) | more than 2 years ago | (#35054934)

this is not intended to be a replacement for silicon but rather a supplementary component for transistors. check out the illustration [eurekalert.org] and notice the caption, "This is a digital model showing how molybdenite can be integrated into a transistor."

so not to worry, everyone who has invested their life savings in sand is perfectly safe.

It may be useful... (0)

Anonymous Coward | more than 2 years ago | (#35055104)

... but it's no dolomite, baby!

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