<azonenberg>
now i can finally try KOH etching with a proper hardmask :)
<bart416>
azonenberg, I did something far more useful!
<azonenberg>
?
<soul-d>
nice , here ill need to use shed so probably won't do much during winter    did find some vacuum stuff but those are called "vacuum excicator"  there is a cheap 5 eur -> http://www.labstuff.nl/contents/media/1g.jpg  wich is supposed to be  a stolp kind of thing just looks like bottle to width is 3,1")
<soul-d>
the problem is not that the 5 euro might hurt but donno about actualy putting a vacume on it
<soul-d>
you have any ranges  you typacily want to work at ? like specs of pump  ?
<soul-d>
not to mention shipping it trough mail :)
<azonenberg>
My guess is that a dessicator will not go below, maybe, 1/10 atmosphere
<azonenberg>
but you need to hit the 1E-6 torr range to get good evaporation
<azonenberg>
So, let's see - my next wafer will be a 50mm <110>
<azonenberg>
One 8x8 block in the middle, thats 64 3x3mm dies
<azonenberg>
plus 12 more around it on each side
<azonenberg>
thats another 48
<azonenberg>
112 dies out of one wafer? That should work nicely
<soul-d>
k have any links of correct products
<azonenberg>
No, unfortunately
<azonenberg>
vacuum is on the list of things to explore
<azonenberg>
but i havent done much with it yet
<soul-d>
does it have to be glassware then ? or like like somthing with a porthole view type of construction although glass has it's advantage with it being inert to most stuff
<azonenberg>
Glass bell jar is what i plan to use
<azonenberg>
yes
<soul-d>
need to build a good safe haven first anyhow for stuff like that  but just wondering  would all metals be vapable ? like alu and silver  just all the same ? since always wanted to make own telescope  but  never wanted to do the silver stuff with chemicals maybe lookup how they vapped up their mirrors  (and maybe a area for you to look at ) ATM amature telescope making
<azonenberg>
All metals can be evaporated, given enough heat
<azonenberg>
i qualify that
<azonenberg>
For example, tungsten would be a little bit tricky ;)
<azonenberg>
It's used in fab often though, but deposited by sputtering
<azonenberg>
You can definitely evaporate aluminum
<soul-d>
only read the word in the books but process wasn;t explained
<azonenberg>
it's actually easier than sputtering it, you need a lot of power to sputter it because you need to break the native oxide off the target
<azonenberg>
and you dont know what sputtering is?
<azonenberg>
It's an alternative deposition process that runs at higher pressures than evaporation
<azonenberg>
When you evaporate, you usually run at the `1E-6 torr range
<azonenberg>
evaporation is much higher, more like 5E-2 torr
<azonenberg>
you fill the chamber with an inert gas, typically argon
<azonenberg>
and run high voltage through it
<azonenberg>
the resulting plasma ionizes the gas and causes the gas atoms to strike your target (the material being deposited) and knock atoms off by kinetic energy
<soul-d>
oh yeah i did read on it
<azonenberg>
note that you are mechanically knocking metal atoms off, so the bulk material is well below the boiling or even melting point
<soul-d>
somthing with dark regions of plasma ?
<azonenberg>
in fact, the target is usually cooled for long depositions specifically to keep it from heating too much
<azonenberg>
Since the pressure is so much higher, the deposition is usually pretty conformal
<azonenberg>
as opposed to evaporation which won't coat vertical structures (edges pointing straight toward the deposition source) well
<azonenberg>
Sometimes this is good and sometimes it's bad, but its a factor to consider
<soul-d>
probably hard to setup at home :P
<azonenberg>
Not really
<azonenberg>
i'm in contact with a prof at a SUNY school that is building one on the cheap as a demonstration
<azonenberg>
IN terms of homebrewing, sputtering needs a more complex apparatus and a means of feeding tiny amounts of inert gas into the chamber
<azonenberg>
evaporation needs much harder vacuum
<azonenberg>
you need a second stage pump
<azonenberg>
but sputtering level vacuum is within the reach of a mechanical pump
<azonenberg>
And the lack of deep vacuum is a nontrivial problem as turbopumps are expensive and diffusion pumps are slow
<azonenberg>
So sputtering is actually higher on my feasibility list
<azonenberg>
all i'd need is an argon canister from a welding supplier and a needle valve
<soul-d>
you do need to have nice buget for it all though
<azonenberg>
Yeah, its not a cheap hobby
<azonenberg>
but a few grand vs a few million? Huge improvement