<bart416>
azonenberg, would you trust a 1000 euro piece of equipment to an ikea table?
<azonenberg>
Depends, i dont have any ikea furiture
<azonenberg>
i have over 1000USD of equipment on a relatively cheap table now that's somewhat worrisome
<azonenberg>
while i am planning to replace it soon i don't feel the gear is in any immediate danger
<azonenberg>
And actually its probably closer to 2000USD
<azonenberg>
two microscopes, probing station, and fiber optic illuminator
<smeding>
hmm
<bart416>
well, this table looks sturdy at first sight
<bart416>
but the "wood" at the top is fairly light
<bart416>
If it's a layer of MDF with cardboard under it to fill up the space I don't mind
<bart416>
But else...
<adc>
whos here
<adc>
this should be a fun chan
<berndj>
data point: i have a former bookshelf, made of chipboard, standing outside; i rescued it from the neighbours' trash 3 winters ago, so it's seen some rain.  parts have swollen, but it's still supporting a few potted plants.  that's about as hostile an environment i can think of for the material
<berndj>
my personal advice would be: don't do anything stupid, like standing on a table to change a lightbulb, while there's a k$-value piece of equipment on it.  don't do it anyway if you're unsure it'll hold: injuries are a pain in the ass (probably literally in this case)
<bart416>
lol
<bart416>
I've seen somebody fall through a glass table already
<berndj>
also, unlike wood, chipboard and i guess MDF fails suddenly and catastrophically - it doesn't "yield" like real wood does
<berndj>
glass also doesn't yield :)
<berndj>
although that's likely to have been tempered glass, no?  so lots of little cubes rather than shards, i hope
<berndj>
i get a weird bit.ly frog in an ice cube :(Â Â something about unregistered domain
<berndj>
i'll try again later
<bart416>
just refresh
<bart416>
I also have it sometimes with imageshack
<XgF>
It's also inadvisible to inspect something on the ceiling while walking on a raised surface...
<XgF>
(Yes, the resultant catching of my leg in the subsequent 1 meter drop hurt)
<azonenberg>
hi adc
<azonenberg>
check the logs and lab notes on the googlecode repo to get up to speed on past work
<bart416>
berndj, does it work now?
<berndj>
azonenberg, i'm a bit behind with your tech.  your Ta2O5... do you start with some tantalum chloride in something-solution or what?
<berndj>
nope, still the frozen toad!
<bart416>
Also, please ignore the teken and doom3 posters, they're glued to the wall >_>
<bart416>
:S
<bart416>
Does it work for you azonenberg ?
<XgF>
works here
<berndj>
maybe my isp is doing weird things
<XgF>
It's my general observation that ISPs are like that
<berndj>
okay, getting it via ssh to another box
<berndj>
maybe some confused "transparent" web proxy getting in the way
<azonenberg>
berndj: yes, i do
<azonenberg>
tantalum chloride in ethanol
<azonenberg>
spin coat, then bake in air at 200C for 1 hour
<azonenberg>
emulsitone tantalumfilm is the product i'm using
<azonenberg>
they dont go into detail on the composition on the main page but the MSDS says its tantalum chloride in denatured alcohol
<azonenberg>
and i confirmed that by EDS
<berndj>
ah, the table.  bart416 i wouldn't worry about leaving expensive stuff on it, unless a) you have Mw 9.0 quakes regularly, b) drunken oafs falling around regularly, c) expensive stuff is more than a few dozens of kg
<nathan7>
azonenberg: and then?
<berndj>
azonenberg, i was just wondering how you got past the insolubility of Ta2O5.  i guess the baking is a sort of roasting process, where you substitute Cl ions with O^2- ?
<nathan7>
on a side note, where do you get that TaCl5
<azonenberg>
berndj: The lowest purity i have is my denatured alcohol (paint store grade) and that is actually bad enough that i saw problems resulting from using it to dilute stuff
<azonenberg>
so i'm gonna try and find highier grade at some point
<nathan7>
I need just a catalytic amount of PdCl2
<azonenberg>
nathan7: Emulsitone won't sell you less than four ounces of their stuff
<azonenberg>
fluid ounces that is
<berndj>
salts indeed, i was playing with water drops and a hot pan (leidenfrost effect) the other day.  there was a "sticky" spot where drops got stuck; eventually a distinctive residue of stuff built up on said spot.  i assume it was perhaps a carbonate type thing
<azonenberg>
And the precious metal based ones tend to run around $500 for that volume
<XgF>
azonenberg: Hmm... what sort of purity do you need on the [denatured] alcohol?
<azonenberg>
When one says denatured alcohol, i assume that it's just ethanol with maybe 5% methanol
<azonenberg>
but this stuff has other things inside too
<azonenberg>
my guess is there's something oily
<berndj>
sigh, i live in possibly the biggest Pd-producing country in the world, but i bet there's no way i can get any in less than ton quantities here
<XgF>
Denatured alcohol always has other stuff inside
<XgF>
Generally things like flavorants so it tastes disgusting
<nathan7>
denatonium
<nathan7>
generally
<azonenberg>
Correct
<azonenberg>
But that's present in trace quantities in my HF too
<nathan7>
o.o
<azonenberg>
and doesnt cause any problems
<bart416>
azonenberg, you need medical grade ethanol
<bart416>
seirously
<nathan7>
like you'd taste it before it's too late
<bart416>
*seriously
<XgF>
The list for UK denatured alcohol is pretty large
<bart416>
It's not that hard to get
<berndj>
or that purple stuff for methanol.  hobos here use bread to "filter it out", apparently
<bart416>
But it's pure
<azonenberg>
bart416: i'm seriously considering doing so
<azonenberg>
apparently you can buy it taxed as a beverage which saves all of the recordkeeping from buying untaxed 100% ethanol
<azonenberg>
costs an extra few $$ per unit volume but if its 500ml of ACS trace metal grade ethanol then the extra $5 wont matter
<bart416>
Or you could try a bottle of cheap russian vodka
<bart416>
That's usually fairly pure ethanol as well :P
<azonenberg>
bart416: waaaay too many organics in that
<azonenberg>
insoluble organics that is
<bart416>
Organics can survive in that?
<XgF>
...99% ABV grain alcohol maybe?
<nathan7>
of course, bart416
<nathan7>
ethanol itself is organic =p
<bart416>
nathan7, I was joking :|
<nathan7>
hits bart416
<bart416>
No but seriously, cheap russian vodka is probably far more pure than your denatured alcohol
<bart416>
but they had something that was chemically identical to SU-8 at first glance
<bart416>
might have been mistaken
<azonenberg>
i see
<nathan7>
If I could find someone who needed 0.5g of PdCl2, I can't afford a gram of that shit
<nathan7>
man, drugs are cheaper than this
<azonenberg>
lol
<bart416>
Palladium is expensive :(
<nathan7>
I should use the Wacker oxidation to make drugs to be able to afford the PdCl2
<nathan7>
except I need the PdCl2 in the first place
<nathan7>
=p
<bart416>
Where could you get palladium cheaply
<bart416>
mhhh
<nathan7>
I should start stealing catalytic converters, I guess
<azonenberg>
:p
<bart416>
Probably
<bart416>
Maybe steal one from a car accident scene before the police gets there
<bart416>
lol
<nathan7>
heh
<bart416>
nathan7, hey cheer up
<bart416>
It's still cheaper than platinum!
<nathan7>
true
<bart416>
Platinum is cool though
<bart416>
Probably one of the safest materials you can possibly handle
<azonenberg>
Gold comes pretty close
<azonenberg>
in terms of unreactivity
<bart416>
well, from a medical point of view gold is better
<azonenberg>
Pt/Pd/Au are all very unreactive
<berndj>
wonders if platinum dust in your lungs would catalyse some mega bad reaction
<azonenberg>
would prefer not to find out experimentally
<berndj>
i thought titanium was pretty much king in terms of biocompatibility. but maybe rather due to relative cost and mechanical properties
<bart416>
pure elemental platinum or not berndj ?
<XgF>
berndj: isn't it the king in terms of biocompatibility while bring /rigid/? :p
<berndj>
bart416, i dunno?  i thought Pt as catalyst was pretty much just the metal?
<bart416>
elemental platinum shouldn't cause too much problems
<bart416>
some irritation I figure
<bart416>
also titanium has its mechanical properties
<bart416>
But gold has some interesting ones as well
<bart416>
azonenberg, that's another thing
<bart416>
You could potentially make bio implants with your Tantalum Oxide processes
<berndj>
heh, okay, not metallic Pt, but cisplatin would be nasty
<azonenberg>
bart416: Not likely :P
<azonenberg>
And i have no idea how biocompatible ta2o5 is
<bart416>
Nah, tantalum is biocompatible
<bart416>
It should be
<bart416>
Ta2O5 is stable as far as I remember
<azonenberg>
its a glass
<azonenberg>
almost indestructible
<azonenberg>
HF is about the only thing that attacks it chemically
<azonenberg>
An order of magnitude or so slower than SiO2
<bart416>
how are the oxygen atoms arranged around it again?
<azonenberg>
No idea
<azonenberg>
I treat it as potentially dangerous since i'd rather not find out the hard way it wasnt harmless
<azonenberg>
iow, with the same caution i'd use with my HF, conc. HCl, etc
<berndj>
except with those you KNOW a priori that they're not harmless!
<azonenberg>
Correct
<berndj>
and they make it pretty obvious that they aren't
<azonenberg>
But the MSDS for this substance indicated it hadnt had any formal toxicity studies conducted
<azonenberg>
So i treat it as potentially nasty
<azonenberg>
i may well be overreacting
<azonenberg>
but i'd rather be safe
<bart416>
looks like Ta2O5 is safe
<azonenberg>
How about the chloride though?
<berndj>
well, i wouldn't inject myself with TaCl5 solution, but if i spilled some on my skin i'd probably wash it off and not worry too much
<bart416>
well yeah, only found one paper on it but meh
<bart416>
Chlorides are bad generally
<azonenberg>
The glass is pretty obviously stable
<azonenberg>
The chloride is what i'm concerned about
<bart416>
Chlorides are generally rather reactive
<azonenberg>
Hence the usual gloves-lab coat-goggles routine
<berndj>
i can't imagine the chloride ion itself could cause much harm: you have plenty of it in your body
<azonenberg>
berndj: The concern is the Ta+ ion
<berndj>
any toxicity would have to be special to the tantalum ioin
<bart416>
Tantalum on its own is biocompatible
<azonenberg>
bart416: Metallic, sure
<berndj>
yeah; i'm just countering the "chlorides are bad" thing.  i think they're generally bad because chlorides are generally more likely to be soluble, hence can get through your skin?
<bart416>
berndj, just saying chlorides are generaly rather reactive, not that they themselves are bad
<bart416>
It's too complicated to bother
<bart416>
Quick glance I'd say Ta+ would start acting very similar to Mg+
<azonenberg>
Meaning?
<bart416>
You're not going to die from it unless it are large quantities
<azonenberg>
Lol
<azonenberg>
But still, i have no plans to become any more casual in my handling of it
<bart416>
lol
<bart416>
You don't want Tantalum bones?
<azonenberg>
lol
<bart416>
What?
<bart416>
Where do you think Magnesium ends up?
<azonenberg>
i'm saying, i dont :P
<bart416>
I thought you'd love that azonenberg, imagine how fun MRIs would become :P
<azonenberg>
lol
<berndj>
my *guess* would be you have more to worry about from the pH effects of TaCl5 interacting with your body than from Ta(V) itself
<azonenberg>
Looks like its nasty if it gets inside
<azonenberg>
but doesnt penetrate skin
<berndj>
but: that page does have a safety section
<azonenberg>
its corrosive but not toxic on skin contact
<berndj>
poison by intraperitoneal route.  iow, don't eat it
<azonenberg>
Yeah lol
<berndj>
lol, LD50 at 1900mg/kg (the higher of two values)
<berndj>
that's close to death by overeating
<azonenberg>
1.9 grams/kg? Yeah lol
<azonenberg>
thats a LOT
<azonenberg>
i dont even know if my entire bottle of solution is that much
<berndj>
i guess treating everything as potentially harmful is a good idea, but on balance i don't think it's necessary to treat it the same way you treat piranha!
<azonenberg>
i wouldnt use piranha in this lab lol
<berndj>
at some point you incur more risk in trying to avoid the original risk, than from accepting the original risk itself
<berndj>
(which i'm not saying you're doing)
<berndj>
how closely can you control the layer thickness?
<azonenberg>
Process control, especially on the tantalum oxide layers, is a sticky point right now
<azonenberg>
i'm having trouble getting consistent good film quality
<azonenberg>
Photoresist and other stuff i can spincoat fine
<berndj>
and, can you produce a "clean" layer of Ta2O5 (smooth, mainly, and uniform thickness)?
<azonenberg>
Over what area?
<bart416>
mhhh, how hard would it be to dispose silver on acrylics
<berndj>
over a square foot or so :)
<azonenberg>
Not even close :P
<azonenberg>
i've had trouble on 2-inch wafers getting uniform coatings
<berndj>
what thickness do you typically try to deposit though?
<azonenberg>
50-100nm
<berndj>
i'm just wondering if it's useful as a reflection-enhancing coating on optics (telescope mirrors)
<azonenberg>
No, in fact the opposite
<azonenberg>
its routeinely used as an antireflective coating on lenses :P
<berndj>
its insolubility would be a boon
<berndj>
antireflective vs reflection-enhancing is just a matter of film thickness :)
<azonenberg>
Hmm, good point
<azonenberg>
In any case i'm having trouble getting good yields with it
<azonenberg>
tonight i'll actually be conducting some experiments with the goal of removing it from my process
<berndj>
in fact i'm surprised they'd use it as an ANTIreflective coating - i'd imagine its "high" refractive index is higher than that of the lens material?  do you have any idea what its index of refraction is?
<azonenberg>
2.5ish i think?
<azonenberg>
thats for bulk material though
<azonenberg>
thin films may be different
<berndj>
would 100nm count as "thin film"?
<azonenberg>
but yes i think its higher than that of the lens
<azonenberg>
Yes
<azonenberg>
Submicron, generally
<azonenberg>
as a rough rule of thumb
<berndj>
still, it's an interesting idea; sounds like it's better than impossible to get hold of, it's water-insoluble, and good transmission window
<berndj>
what sort of non-uniformity were you getting?
<azonenberg>
First, pinholes in the surface
<berndj>
local or global, specifically?
<azonenberg>
those were local and went all the way through the layer but were tiny
<berndj>
i think pinholes wouldn't be a problem for a reflection coating
<azonenberg>
Then there were global thickness variations as well, probably due to viscosity of the solution
<azonenberg>
i think i need to thin it down more
<berndj>
more important would be if you could maintain thickness to within a dozen percent over a square foot
<azonenberg>
A dozen percent? Hmm
<azonenberg>
I'm getting visible color variations right now over a 2-inch wafer
<berndj>
even if not, it would probably still be better than no coating at all
<azonenberg>
But hopefully the process can be improved to the point that this goes away
<berndj>
do you know that those color variations are due to film thickness variations, and not just viewing angle?
<azonenberg>
They show up under microscopy from a straight-down angle
<berndj>
you could expect circles of fixed path length-difference showing up
<azonenberg>
and are consistent as i move around
<berndj>
sounds like the film then
<azonenberg>
these are theta-related
<azonenberg>
streaks going from center out to the rim, slightly thicker or thinner than the rest
<berndj>
oh right, yes, that does sound like what i'd expect from spin coating + too much viscosity
<azonenberg>
Yes
<berndj>
in fact i'm still surprised that spin coating works at all in giving a ~uniform film thickness
<azonenberg>
I need to get higher purity ethanol
<azonenberg>
to thin the solution down
<azonenberg>
the stuff i was using seems to be contaminated somehow
<berndj>
could ethanol evaporation be causing problems?  you'd have locally more-concentrated regions, which would be more viscous
<azonenberg>
I dont think so, i got better results in the past
<azonenberg>
there is a contaminant somewhere and i suspect my ethanol
<azonenberg>
But one experiment was anomalous
<berndj>
anyway, i don't think one can (easily) spin-coat a miror!
<azonenberg>
i got the same result from using pure tantalumfilm with no dilution
<azonenberg>
so either it wasnt as pure as i thought
<azonenberg>
or there is another variable out there
<azonenberg>
one i'm not seeing
<berndj>
wait, how much water was in your ethanol again?
<azonenberg>
i dont know
<azonenberg>
The tantalumfilm is 16% solids by weight, the remainder is semiconductor grade denatured alcohol (which basically means ethanol+methanol w/ nothing else)
<azonenberg>
I prepared a dilution of a few drops of this mixed with my ethanol
<azonenberg>
Which is paint store grade
<azonenberg>
i dont even have an msds for it listing the denaturants
<berndj>
yeah, i imagine any water at all would cause partial hydrolysis
<azonenberg>
Ooh, interesting
<berndj>
disclaimer: i'm just parroting wikipedia and my other google results from the last hour
<azonenberg>
you're thinking my ethanol is contaminated with water
<azonenberg>
and that its hydrolyzing some of the stuff on contact without heating?
<berndj>
something like that
<XgF>
Water would be an especially cheap denaturant
<berndj>
so there might be some tantalum oxychloride
<azonenberg>
berndj: The results i was seeing were catastrophic though
<azonenberg>
not a slight degradation in film quality
<azonenberg>
there was no film to speak of
<azonenberg>
It beaded up and didnt stick to the surface
<berndj>
yikes
<berndj>
it was that "flaky" looking stuff in your pics?
<azonenberg>
No
<azonenberg>
worse
<azonenberg>
i pipette a ml or so of the solution (pure or diluted) onto a wafer
<nathan7>
OXYCHLORIDE, POW
<azonenberg>
spin at maximum speed on my spin coater
<berndj>
oh no, the flaky stuff was your PR
<nathan7>
oh
<azonenberg>
before spinning it formed a nice thin layer over the wafer
<azonenberg>
as i spin, i see it gradually thinning
<azonenberg>
then radial lines start appearing
<azonenberg>
(well before it hits the desired thickness)
<berndj>
a sort of surface tension thing?
<azonenberg>
so i remove power and spin down
<azonenberg>
and i see balls of solution in a relatively random pattern across the surface
<azonenberg>
some free, some connected by narrow lines of coated area
<azonenberg>
the rest of the silicon was uncoated
<azonenberg>
wish i had a photo but my hands had something on them and i didnt want to contaminte my camera
<berndj>
sounds like a surface tension issue
<azonenberg>
Agreed
<berndj>
your "silicon" (or maybe more likely, the SiO2 covering it) didn't like the film
<azonenberg>
hence why i suspected a contaminant in the film
<azonenberg>
Since in the past it had worked beautifully
<azonenberg>
I tried stripping native oxide in HF
<azonenberg>
and coating immediately
<nathan7>
quaternary ammonium salt might help with wetting
<azonenberg>
that didnt work any better
<azonenberg>
So i re-grew the oxide in heated 3% H2O2 (didnt wnat to wait a week for it to form on its own)
<berndj>
can contaminants cause such gross changes in surface tension behaviour?
<nathan7>
I figure it'd degrade to N2 during the oxidation steps
<azonenberg>
verified native oxide was present by the water-droplet test
<azonenberg>
and coated again
<azonenberg>
still didnt work
<nathan7>
:(
<azonenberg>
after three or four tries it spontaneously worked
<azonenberg>
i baked it, not wanting to risk losing a semi-decent film
<azonenberg>
then after several tries got an ok-ish one on the back side
<azonenberg>
But i have no idea what the variable was
<azonenberg>
Some of my best Ta2O5 films were gotten by diluting with alcohol
<berndj>
ethanol soaking up whatever impurities were on the wafer?
<azonenberg>
the same alocohol that i previously thought was my problem
<azonenberg>
I did an acetone rinse, then a native oxide strip followed by regrow
<azonenberg>
not a full RCA clean but should have gotten everything but trace metals
<azonenberg>
I'm now out of <110> wafers so i cant run any more tests of this type until i order another one from MTI
<azonenberg>
probably next month
<azonenberg>
In the meantime, i have these two wafers
<azonenberg>
one with so-so Ta2O5 on both sides and the other without any oxide
<azonenberg>
both coated in 5nm Cr and 1000nm Cu
<azonenberg>
on the polished sides
<azonenberg>
(one is double side and one is single)
<azonenberg>
Going to do some KOH testing to see how well the CuCr stack handles it
<azonenberg>
if the Cr improved adhesion enough i may be able to ditch the Ta2O5 entirely
<azonenberg>
at least for shallow etches
<azonenberg>
Also, Cr has virtually zero etch rate in KOH
<azonenberg>
actually no sorry
<azonenberg>
i was thinking Ni
<nathan7>
the only etching would come from oxidation and stuff, I figure
<azonenberg>
Cr is around 5nm/min - low but definitely nonzero
<azonenberg>
KOH + Cu i'm told does react slightly
<nathan7>
in an inert atmosphere it'd be zero
<nathan7>
and yes, that forms cuprate if dissolved oxygen is there
<nathan7>
again atmosphere screwing with it
<azonenberg>
How would i go about removing said oxygen? :P
<nathan7>
inert atmosphere, run the water over something reducing
<berndj>
like potassium metal!
<nathan7>
Yeah, that'll reduce your water too.
<azonenberg>
lol
<nathan7>
I figure H2 could help
<azonenberg>
how about cesium :P
<nathan7>
heh
<berndj>
i hope you guys have seen that sodium party website
<berndj>
H2 in presence of catalyst (Pt?): not a bad idea
<nathan7>
Yeah.
<nathan7>
Pd can absorb H2
<nathan7>
and if you buy Pd, azonenberg, give me a little =p
<azonenberg>
nathan7: Do i look like i'm made of money? :P
<nathan7>
0.3g will do, sir
<azonenberg>
good luck finding anyone willing to sell you 300mg of the stuff
<nathan7>
Yeah. I should try cocaine.
<nathan7>
maybe it works as a catalyst.
<bart416>
lol
<azonenberg>
Lol
<bart416>
what do you guys think about using conductive epoxy and then copper plating that
<azonenberg>
bart416: For what?
<nathan7>
that
<nathan7>
I should try that
<azonenberg>
I was considering it for via plating
<nathan7>
that sounds viable
<azonenberg>
:P
<nathan7>
or spend ¬50 on a gramme of PdCl2
<azonenberg>
Use something conductive, maybe silver pen or maybe conductive epoxy
<azonenberg>
then electroplate up
<berndj>
via plating: another interwebs research project that has so far frustrated me
<bart416>
I'm considering it for making multilayer pcbs
<nathan7>
PdCl2 is the standard way of doing vias
<nathan7>
PdCl2, then SnCl2
<berndj>
again, afaict palladium / platinum seem to be involved
<nathan7>
then electroless plate it
<nathan7>
and then electroplate
<azonenberg>
If anyone wants to put some time into developing a non-PdCl2 based process for via plating i'd be interested
<nathan7>
¬50 for 1g of PdCl2, lasts a lifetime
<berndj>
hmm... find a PCB manufacturer who'll let you scoop out a teaspoon of PdCl2?
<azonenberg>
lol
<bart416>
I'm probably just going to end up asking a chemistry professor what's the best way to electroless copper plate something without killing yourself
<nathan7>
Hmm?
<nathan7>
electroless copper is just an aldehyde and a copper salt afaik
<azonenberg>
Like i said i'll gladly collaborate if you guys want to test a process
<nathan7>
I wonder if auric chloride or something would work as well
<berndj>
collaborate, v., t.; we suggest random crazy stuff and azonenberg tries it out
<azonenberg>
lol
<bart416>
nathan7, there's more to it
<azonenberg>
I expect some degree of sanity to the suggestions
<nathan7>
surfactants and things
<bart416>
You need to keep the pH in check
<bart416>
And most methods generate cyanides
<azonenberg>
Oh fun
<azonenberg>
Anybody see problems with silver ink + electroplating?
<nathan7>
not me
<azonenberg>
Do this before laying down photoresist
<berndj>
i think some ppl in the homebrew pcb world do exactly that
<nathan7>
bart416: cyanides, are used for electroplating
<nathan7>
matte electroplating
<azonenberg>
Then spin coat the board in PR, expose, develop, etch
<azonenberg>
Actually, maybe do the PR first
<nathan7>
I have gotten beautiful shiny Cu plates with CuCl2
<azonenberg>
nathan7: CuCl2? Interesting
<azonenberg>
How did you synthesize that
<nathan7>
It works damn well.
<bart416>
nathan7, I can do basic chemistry
<nathan7>
I had some Cu(OH)2 left over from something
<berndj>
HCl + H2O2 + Cu
<bart416>
But I'm certain there is a better way than anything we can come up with
<azonenberg>
Because CuxClx is a waste product of HCl:H2O2 etching of Cu
<nathan7>
azonenberg: get CuO at pottery place
<bart416>
I want something with chemicals I can buy easily without having to fill in 50 pages of paperwork if possible
<azonenberg>
I have a pretty significant amount of it (though dilute)
<nathan7>
hmm
<berndj>
did you mean *pure* CuCl2?
<nathan7>
etch PCBs with CuCl2/HCl(aq)
<azonenberg>
And if i could plate it out onto vias rather than having to dispose of it as hazardous waste
<nathan7>
berndj: (aq), acidified.
<nathan7>
to a fancy green colour :D
<azonenberg>
that would improve things
<nathan7>
I use a copper anode
<azonenberg>
I could certainly boil it down to a reduced volume
<nathan7>
I dunno, I try to keep it somewhat concentrated
<azonenberg>
the stuff i have is quite dilute because whenever i rinse Cu+ contaminted glassware (like etch beakers) i dump the first rinse in the waste jar
<berndj>
nathan7, do you know what potential you need to maintain to avoid etching the electrodes?
<nathan7>
I have a something big amount of transition metal waste
<nathan7>
in the form of hydroxides, some carbonates
<nathan7>
meh, no, all hydroxides really
<nathan7>
berndj: unsure
<nathan7>
I was just plating experimentally for solderability
<azonenberg>
My waste right now is three big 950ml containers
<berndj>
my teenage electrolysis / electroplating experiments always just ended up as a green/grey/brown sludge :(
<azonenberg>
one (nearly empty) is HF based
<nathan7>
well, teenage I am
<nathan7>
and my electroplating seems to go fine (=
<azonenberg>
one is HCl/H2O2/CuxClx/water
<berndj>
which i now figure must've been Cu(OH)n
<nathan7>
Acid, my friend.
<nathan7>
You need more Hz
<azonenberg>
and one is mixed solvent waste (acetone, IPA, ethanol)
<nathan7>
Apparently CuSO4/H2SO4 works well too
<nathan7>
but I have little H2SO4
<nathan7>
fucking hell, a CFL
<nathan7>
a *shitty* CFL at it
<berndj>
the last time i tried to plate anything was to get even just a *little* Cu onto an aluminium laser pointer battery tube
<nathan7>
Al..
<nathan7>
Al is hell to plate
<berndj>
didn't plate nicely at all thoughj
<nathan7>
you need to do zinc first
<berndj>
yeah, that damn oxide layer no doubt
<nathan7>
before you plate *anything* onto Al, Zn first.
<berndj>
but it "worked": i managed to solder something onto the tube
<nathan7>
Al reduction is an excellent way to make metal powders
<bart416>
copper plating acrylic sucks
<bart416>
I've done a few attempts already
<nathan7>
acrylic?!
<bart416>
plexiglas
<nathan7>
awesome
<nathan7>
I know
<azonenberg>
how do you do that
<nathan7>
PMMA, acrylic, plexiglass
<bart416>
azonenberg, as described above
<azonenberg>
But its nonconductive?
<nathan7>
all the on-plastic plating seems to use PdCl2 first
<bart416>
yeah, that's the issue
<bart416>
My film forms
<bart416>
but doesn't stick
<nathan7>
then they do electroless Ni
<azonenberg>
ony plating methods i know of are electroplating, evaporation, and sputtering
<azonenberg>
for metals
<azonenberg>
and CVD for glasses
<azonenberg>
then spinning for polymers
<berndj>
azonenberg, i don't think this falls into your "sane" qualifier, but i was wondering if one could plate a pcb with gelatine or something, add bacteria, a mask, and a germicidal lamp
<berndj>
would be interesting to know the vapour pressure of pcb materials