<nmz787>
yeah but most companies have beginner models... also, microscopes aren't really anything new tech wise, once you know how to make good defect-free glass and shape it according to some CAD drawings that were verified in simulation... it's pretty straightforward
<nmz787>
surely having /more/ complex optics, or /more/ aberration-correction will not be present in cheaper models... but I'd say it's pretty well split between these and those
<nmz787>
i.e. you aren't getting really really nice optics until you're well into the several thousand-dollar items
<nmz787>
or if you want some snazzy peltier-cooled CCD on the unit, which itself will run thousands
<nmz787>
or some fluorescense filters, or notch for doing Raman
<nmz787>
this goes back to: depends on what you want to do
<nmz787>
personally all my microscopes are from craigslist or a thrift store
<CoolCmos>
any recommendations for doing the simpilist most primitive lithography.. maybe 80s tech even or later if not much different
<CoolCmos>
irc needs time stamping so i know how long its been since the last people were talking
<CoolCmos>
nmz787 ?
<CoolCmos>
please
<nmz787>
CoolCmos: I bought a $100 405nm laser cutter/etcher to do some lithography, with the intent of upgrading it to a blu-ray R/W laser (still 405nm, but with near diffraction-limit optics)
<CoolCmos>
yes but will it come close to any kind of vlsi
<nmz787>
ahh "4/18/2017 - Sorry, we sold out all our kits and stock and we don't have plans to restock our shop.
<nmz787>
"
<CoolCmos>
and i was more concerend with the chemical layers
<nmz787>
CoolCmos: in ~1980 tech was using 1000nm process node
<nmz787>
you said lithography
<nmz787>
that means "light drawing"
<nmz787>
if you're asking about ion implant... that is what you do after lithography
<CoolCmos>
yes on a chemical for layering
<CoolCmos>
no ion implant
<CoolCmos>
insulative
<CoolCmos>
metal
<nmz787>
by chemical, I guess you mean photoresist?
<CoolCmos>
photo resistive
<nmz787>
this is not something that is inside an IC after it is all made
<CoolCmos>
what i dont understand is how you etch metal and remove it
<CoolCmos>
mainly any way
<nmz787>
it is just a 'mask' so when you do ion implant, the stuff with photoresist on it doesn't get the ion dose, only the parts that were not covered will get ion dosage
<CoolCmos>
yes my book was showing it being removed
<nmz787>
the photoresist also gets ion dosage, but then you strip it off
<nmz787>
you add metal by sputtering or deposition
<nmz787>
you etch with etchants
<CoolCmos>
please explain
<nmz787>
what don't you understand about what I just explained?
<nmz787>
you can get photoresist on ebay for like $5
<CoolCmos>
the sputtering and deposition processes methods and etching process methods
<CoolCmos>
nice ill have to get some when im ready
<nmz787>
I really don't know too much, but basically you have a cylinder, at the top is a chunk of metal you wish to sputter, at the bottom is an electrode, and in-between you put your sample/wafer... then you pull vacuum, and use then pass high voltage through (top metal you want to sputter is one electrode, and the bottom electrode is the other)
<nmz787>
the high-voltage will ionize the metal, and it will fly through the vacuum towards the other electrode, but your sample gets in the way and gets coated
<CoolCmos>
great i was trying to avoid hazardous equipment
<nmz787>
etching is either a liquid or gas/plasma phase
<nmz787>
sorry, most stuff requires high-energy to activate/destroy bonds
<CoolCmos>
how is deposition different
<nmz787>
not terribly sure, but I was reading recently about ALCVD (atomic layer chemical vapor deposition) and in that case you use chemicals which have high-reactivity
<nmz787>
usually a metal with some carbon tail
<nmz787>
the metal attaches to the sample, then the carbon tail is pulled away with vacuum as it turns into a gas
<nmz787>
ALCVD uses a two-step process, where a monolayer can only deposit, because the chemical won't interact with itself
<nmz787>
so then use swap to a different chemical
<nmz787>
which re-activates the outer-most layer
<nmz787>
then you repeat those 2 steps
<nmz787>
pulsing the first chemical, flushing, then the second, and so on
<CoolCmos>
if etching is aliquid what does it need more photo resist
<nmz787>
(pulsing meaning with gas pressure)
<nmz787>
please rephrase your last question
<CoolCmos>
to etch the metal
<CoolCmos>
you said etching was a liguid
<CoolCmos>
but you would need to lithograph it first
<nmz787>
right, so the etchant can't touch all the metal
<CoolCmos>
so woudl the same photo resist work for the metal etching
<nmz787>
just like if you put a mask on your face, then someone threw water at you... only your eyes and nose might get wet
<nmz787>
well there are 100s if not 1000s of types of photoresist
<nmz787>
so it depends on the chemistry you are using
<CoolCmos>
ok its late and i had a busy day.. thanks so much for the input
<nmz787>
but if the etchant attacked the resist, then it wouldn't be a very good system