Creating a purer breed of semiconductors
FANS OF ELECTRON mobility research rejoice! Boffins at Germany’s Physikalisch Technische Bundesanstalt (PTB) have come up with a brand spanking new high-vacuum semiconductor crystal generation process which purports to produce crystals five times purer than all previous known epitaxy systems.
PTB’s new system apparently relies on an innovative molecular beam epitaxy system, with GaAs (gallium-arsenide) and AlGaAs (aluminum-gallium-arsenide) semiconductor heterostructures forming a base. These are then evaporated in a vacuum and laid down in atomic layers, only a few nanometers thin. These then form an electron layer within the crystals, called a two-dimensional electron gas.
Mobility of electrons depends quite significantly on lowering the amount of impurities, so, to mop up the nasty stuff, the boffins have added special cooling panels to suck up any unwanted waste.
To generate the crystals themselves, a special ultrahigh vacuum is used. At 15 orders of magnitude beneath standard atmospheric pressure, you could say, it sucks. Big time. It is also, by no means, an easy feat and requires multiple stages of vacuum creation, starting with partial vacuums and moving up.
Once the vacuum has been formed, the molecular-beam epitaxy gets going, allowing the incredibly pure crystals to form using the aforementioned layering system.
All this, ultimately, leads to a much purer form of semiconductor, which is good news for Chipzilla and Moore’s Law advocates, as well as to those looking into things like quantum Hall resistance metrology and new thinking on electrical current as a function of frequency and electron charge.
Exciting stuff indeed. µ
L'Inq
PTB
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Methinks perhaps the title pokes a little at German history, particularly in the past century?

I was at Johnson Space Center recently and saw the HUGE vacuum chamber where they test space hardware. The door alone is over 10m in diameter (40 feet). The NASA guys were telling me they could get down to 10 to the minus 6 torr (one millionth), so these guys getting down to 10 to the minus 15 is quite a feat. But still, NASA is dealing with a slightly larger volume.
A who's a jigga what?

Definitely 10 uber spod points to you for getting in as many unintelligible works in an article as possible, but really... WHAT??
Surely it'd be cheaper to evacuate a chamber mostly, fill it with Helium, evacuate that, flood the remnant with Helium, THEN begin the sensitive process (sensitive to oxidization, carbon dioxide, nitrogen, whatever) than it is to operate fully in vacuum?

And why wasn't the same technique used for all the UV capable telescope mirrors, as well? (since oxygen can degrade significantly, the reflectivity of aluminum).

Displacement of problem gasses is cheaper than a hard vacuum, every time.
This is a nice academic study, but I'm wondering what the point is - especially on a site like this. THIS HAS NOTHING TO DUE WITH MOORE'S LAW! Unless you think somehow this will allow an increased transistor density (which is what Moore's Law is). It could (in theory) produce faster devices - which of course is not Moore's law.

One would think someone writing about MBE, and GaAs would at least know what Moore's law is and be able to distinguish geometric scaling with transistor speed. 
When I read this stunning news about molecular beam epitaxy, I nearly dropped my HobNob.
this begs the question: what kind of research is done on the ISS, and would shouldn't the semi industry be looking into space as the final fabbing frontier?