semiconductors from stone knives and bear skins

[hombre]

I'm wondering if it's possible to make LEDs, displays and semiconductors using a big ion deposition machine. The machine would be like a very slow and doubtless huge 'replicator' that can manufacture a wide variety of things by spray-painting atoms onto a substrate.

 

Ideally the device would also dissociate and purify the silicon, metals and other substances as they are used, like a mass spectrometer; it would not have to be frequently dismantled for cleaning or maintenance (unlike a mass spectrometer); and it would not contain anything extraordinarily rare or costly. If anyone takes an interest, how big would such a machine have to be for a yield of, say, a gram of product per day? What would the basic design look like?

 

Right... I'll get it started myself by calculating the obvious. Lets assume that what we're making is mostly silicon. One gram of Si is 2.7 x10^22 atoms. That's 4.4kC (4400 'coulombs') of Si per day (assuming the atom stream is of silicon atoms with one extra or one missing electron); which comes to just 50ma. That's a lot for an ion gun. It's a lot even for 100 ion guns.

 

Using many guns in parallel confuses things a bit. Maybe one biggun?

[Schrödinger's hat]

Sounds like a massive energy sink.

[hombre]

The efficiency wouldn't be great, but efficiency isn't the goal.

[Klaynos]

Something like this:

 

http://en.wikipedia.org/wiki/Physical_vapor_deposition

 

??

 

There is a method that I think is very similar to what you are describing but I can't recall what it's called right now.

[hombre]

Thanks, but what I'm looking for is more like this: Ion beam deposition - Wikipedia, the free encyclopedia

 

Also known as 'soft landing' deposition. To make semiconductors, we need to make micron-sized features.

Edited December 15, 2011 by hombre

[Klaynos]

Micron sized in which direction? Height or lateral? I've spent a bit part of the last 4 years looking into making micronscale structures in a type III-V semiconductor.

[hombre]

Just a functioning semiconductor made by any means. A processor, say, or a power transistor. Imagine a machine that you could dump a bucket of dirt and sand into and get finished semiconductors out the other end.

Edited December 15, 2011 by hombre

[Xittenn]

Hi! Look up ZnO TFT Deposition . . . .

[hombre]

If anyone wants to pursue this further, please post here [link removed by moderator]. Thanks!

Edited December 16, 2011 by Klaynos

[Klaynos]

If anyone wants to pursue this further, please post here [link removed by moderator]. Thanks!

 

It seems you're trying to replace a whole load of complex processes with one black box... That is going to be very costly and probably not worth the effort.

[hombre]

Oi! You took away the link to my ad-less, profitless, inoffensive little board.

 

No, the machine does not make sense in a capitalist system. It's purpose is to provide devices and reactants for electronics, automation and pharmaceuticals in a zero-growth, non-polluting society. There is no other way to make such things without mining and pollution. Afaik.

 

The cost of the machine doesn't matter, only the labor required to keep it running matters. It has to be low-maintenance and made of fairly simple materials. No rhenium. No molybdenum.

 

I'm open to suggestions. We can purify the Si by the old method of crystallization, that at least should simplify the job quite a bit.

Edited December 16, 2011 by hombre

[Klaynos]

Oi! You took away the link to my ad-less, profitless, inoffensive little board.

 

No, the machine does not make sense in a capitalist system. It's purpose is to provide devices and reactants for electronics, automation and pharmaceuticals in a zero-growth, non-polluting society. There is no other way to make such things without mining and pollution. Afaik.

 

The cost of the machine doesn't matter, only the labor required to keep it running matters. It has to be low-maintenance and made of fairly simple materials. No rhenium. No molybdenum.

 

I'm open to suggestions. We can purify the Si by the old method of crystallization, that at least should simplify the job quite a bit.

 

 

I meant cost not just in terms of money but the amount of effort it would take to develop. Any such device would also be incredibly complicated and therefore very susceptible to failures. It's really very complex to go from a lump of rock to a MOSFET.

[hombre]

I am not so pessimistic. I exaggerate when I say 'a bucket of dirt and sand' going in to one end. It's true that such a machine would be mass-rejecting all kinds of stuff that would want to crust all over the interior; but even that can be minimized by starting with pure-ish substances and making it target 'junk spots' to accumulate the garbage (assuming a time-of-flight approach). Aside from a filament (possibly) in the ionizer, the thing would be a bunch of dead-end electrodes and almost no moving parts. The rest is electronics that it can stockpile. What's to break?