<azonenberg>
Going pretty well, I'm going to be doing another few experiments over the weekend with the goal of preparing specimens to cross-section image on the SEM later on
<azonenberg>
i want to measure some of my layer thicknesses
<azonenberg>
My Si wet etch process pretty much works, the only thing left to do is fix the exposure source (better lamp) and use a thinner Ta2O5 layer to reduce overetch
<azonenberg>
if all goes well i'll do another evaporation run in mid-august on half of a <110> wafer coated in ~50nm Ta2O5
<azonenberg>
put 100-200nm of Cu on that
<azonenberg>
then cleave into dies and start actually building devices
<B0101>
oh, thats interesting.
<azonenberg>
End of August to early September i should be able to do some high-aspect-ratio tests
<azonenberg>
then soon after that build an actual comb drive
<azonenberg>
all of the other processes are mostly figured out
<azonenberg>
I'll probably do the first version really simple, only a couple of fingers with barely visible motion
<B0101>
hmm... ok
<B0101>
Azonenberg: You should make some videos about your experiments
<azonenberg>
B0101: Maybe at some point
<azonenberg>
A lot of the litho has to be done under darkroom conditions so there wouldnt be much to see
<azonenberg>
But if i have some time i can try to set something up
<B0101>
Do you have an electron microscope?
<B0101>
Ok, I am just kidding, of course its too expensive
<azonenberg>
B0101: Not *yet*
<azonenberg>
But i can get access to one on campus here and there
<azonenberg>
And I plan to buy one in about 5-10 years when i have the budget
<azonenberg>
It'd cost about as much as a decent car
<azonenberg>
*nice car
<azonenberg>
$20K ish
<azonenberg>
Hmm
<azonenberg>
If I evaporate 80/20 NiCr it should resist KOH nicely
<azonenberg>
without need for a secondary hardmask
<azonenberg>
But i dont know if it will work with tungsten boats
<bart416>
azonenberg, IR camera...
<azonenberg>
?
<bart416>
Isn't the photoresist UV sensitive?
<azonenberg>
Oh
<azonenberg>
You mean for filming stuff
<azonenberg>
Yeah, IR would work if i had one
<azonenberg>
The only IR camera i have is focused for really short range
<azonenberg>
like 6"
<azonenberg>
And isnt easy to refocus (electrical tape holding the lens elements together, etc :P)
<bart416>
Old CCD webcams are pretty IR sensitive if you remove the filter and replace it with a piece of photo film
<azonenberg>
bart416: Thats actually what i have
<azonenberg>
I have no filter at all
<azonenberg>
so it's sensitive to visible + IR
<bart416>
Ah
<azonenberg>
But the lens got a bit messed up and kinda hacked
<bart416>
Then again, I sort of had a lot of time to perfect it
<azonenberg>
so its held together in what happens to be a very short range focus
<bart416>
We have to do some sort of uhm thesis like test at the end of highschool
<bart416>
(obviously less complicated)
<bart416>
Mine was about tracking a hand against a wall
<bart416>
We solved the skin colour problem by IR, also way less noise heh
<bart416>
But it depends on a camera to camera basis if it works well
<bart416>
The cheaper ones are usually easier
<bart416>
azonenberg, how paranoid are those idiots :|
<azonenberg>
lol no idea
<bart416>
Also, I got my BGA soldering process to work while drunk, lol
<azonenberg>
lol
<bart416>
That's the good news
<bart416>
The bad news is that I went through roughly 40 ICs to get it to work well
<azonenberg>
Lol
<azonenberg>
What pitch?
<azonenberg>
and what kind of pcb?
<bart416>
scrap pieces of dual layer PCB
<azonenberg>
And what kind of chips?
<bart416>
0.4mm
<azonenberg>
o_O
<bart416>
NVRAM
<azonenberg>
and i thought the 0.8s i had were small
<azonenberg>
Grr
<azonenberg>
Four more pins to route
<bart416>
lol
<azonenberg>
in a sea of wires between an FPGA and a SRAM
<bart416>
I'm looking into package on package for my ARM Cortex board
<azonenberg>
These things are blurring the line between PCBs and ICs
<azonenberg>
using photolithography and plasma etching for vias
<azonenberg>
resistors and caps embedded in the board
<bart416>
I wonder if you could layer / layer deposit your own PCB to more than two layers
<azonenberg>
Given a vacuum evaporator and such, i could make them using IC-style materials :P
<azonenberg>
500nm Cu + 200nm SiO2
<azonenberg>
per layer
<azonenberg>
Start with a dual layer FR4+30um Cu substrate for power
<azonenberg>
lay down a thick dielectric layer, punch vias
<azonenberg>
fill vias with conductive material and CMP flat
<azonenberg>
Well its 0430 here and i've been up a bit longer than planned... time to get some sleep lol
<bart416>
lol
<bart416>
'nite
<R0b0t1>
azonenberg, whoah
<berndj>
azonenberg, hi.  speaking of vacuum evaporators, do you think FR4 would outgas too much for a nice layer of Cu?  at least Cu isn't crazy reactive like Al is, but still... need to have a good free path length
<berndj>
that pacman ghost thing or whatever it was is cute :)
<nathan7>
berndj: the nyanotechnology?
<lekernel>
given that FR4 smells sometimes, it probably outgases
<azonenberg>
berndj: Hmm
<azonenberg>
I've evaporated Cu before, but on Si and SiO2
<azonenberg>
and Ta2O5
<azonenberg>
if anything outgasses it'd be the epoxy
<azonenberg>
the glass wont care
<azonenberg>
lekernel: What you might be smelling is particulates though
<azonenberg>
But yes, it probably does
<azonenberg>
berndj: also, that's a nyan cat
<berndj>
oooh the one that's rainbow-propelled!
<azonenberg>
Yeah
<azonenberg>
Didnt you recognize it?
<berndj>
no, my pop culture fu is rather weak
<B0101>
Azonenberg: Hi, have you got any updates or discoveries
<azonenberg>
B0101: Running some copper experiments tonight in an hour or so
<B0101>
hmm for the interconnects?
<azonenberg>
For hardmask, actually
<azonenberg>
I want to see a) how well it survives KOH, and b) design a better etch