<wolfspraul> hi qi-bot
<azonenberg> wolfspraul: is that your CIA bot?
<wolfspraul> no irc logging
<wolfspraul> wait I need to test a bit more
<azonenberg> Ah
<azonenberg> Let me work on setting up CIA then
<B0101> how do you add the CIA bot?
<azonenberg> B0101: cia.vc
<azonenberg> I'm still configuring it
<azonenberg> There we go
<azonenberg> Anybody here interested in getting added to the Google Code project? You'll start out as a contributor plus edit permissions on the wiki
<azonenberg> just send me your googlecode email address
<B0101> Can I do it?
<wolfspraul> azonenberg: I think it works http://en.qi-hardware.com/homecmos-logs/
<wolfspraul> search works too
<azonenberg> B0101: can you join the googlecode project? Sure, PM me your googlecode email
<B0101> Ok... Gimme a second
<azonenberg> wolfspraul: hmm... this means my email shows up in logs *wonders if there's a way to spamproof this*
<wolfspraul> sorry got disconnected
<wolfspraul> azonenberg: those logs are updated every 30 minutes
<azonenberg> ah
<azonenberg> Can you clear them? CIA dumped an email address i'd rather not get too spammed into the channel
<azonenberg> working on a new filter that'll spam-sanitize emails
<wolfspraul> no need to do more instantaneous, I think. From my experience so far, the most important is a good search feature, and that works.
<wolfspraul> sure, will do
<wolfspraul> as for the logs themselves, I can totally give you server access and you can do with them whatever you like
<wolfspraul> so later we can always cleanup, move all to one domain, or whatever you want
<wolfspraul> I'm not an information hoarder :-)
<azonenberg> Lol
<azonenberg> Yeah, as of now i just want the info to be out there where people can find it
<wolfspraul> just email me your public key (wolfgang@sharism.cc)
<azonenberg> SSH or GPG?
<wolfspraul> ssh
<wolfspraul> so I think 'search' is what most people use
<wolfspraul> it works quite well
<azonenberg> Yeah, agreed
<azonenberg> wolfspraul: For now i can't see any easy way of doing search-and-replace on usernames, and since googlecode insists on using emails as usernames i'll just not include the author in the CIA message
<azonenberg> just the files and log message
<berndj> "pyrex" isn't pyrex anymore; "pyrex" is just a trademark, and modern cookware labelled "pyrex" is no longer borosilicate, but just tempered soda-lime glass
<azonenberg> berndj: Interesting
<azonenberg> I knew pyrex was a trademark but i just assumed it was all borosilicate
<azonenberg> Most of my actual labware is Borosil brand
<azonenberg> And i know for a fact that's borosilicate still :P
<CIA-67> [removed] * r78 /wiki/FreeEDATools.wiki: Created wiki page through web user interface.
<azonenberg> I thought i fixed that, hmm
<berndj> labware would typically be borosilicate, i imagine
<azonenberg> Let's try this again...
<berndj> amateur telescope makers greatly regret the decreasing availability of borosilicate
<CIA-67> 79 wiki/FreeEDATools.wiki Dummy commit to test new CIA bot configuration
<wolfspraul> azonenberg: I'll clean it later if you don't mind
<wolfspraul> during the day the log file is open, so I have to restart the bot (don't know better)
<azonenberg> No rush, i just dont want to leave it up there for a long time to get spidered
<wolfspraul> I'll go through tomorrow and remove the address...
<azonenberg> Ok, thx
<CIA-67> homecmos r80 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<azonenberg> There we go
<azonenberg> B0101: You're now a contributor (can file tickets on the bug tracker, comment on tickets, and comment on wiki pages) plus EditWiki permissions
<azonenberg> if i see good work you may get full commit access in the future
<azonenberg> Anybody else?
<azonenberg> B0101: The FreeEDATools wiki page is just a start, if you're looking for something to work on feel free to add some more content there
<B0101> ok
<azonenberg> As with all of the other wiki pages, of course, but that's one that i specifically know needs work
<azonenberg> Going to grab a bite, then off to the lab for some testing of liftoff patterning using a slightly thicker hardmask than yesterday
<berndj> i just checked, magic's native file format looks pretty merge-friendly
<azonenberg> berndj: Interesting, I might have to take a look at that
<berndj> its UI does however look like something that escaped from 1980
<azonenberg> I'm not really tied down to Glade very much, i only have a few test patterns and i can always dump them into a GDS and pull them into another tool
<berndj> but i found i got used to it fairly quickly
<azonenberg> Want me to set you up on the googlecode project too? You can add such info to the wiki
<berndj> i don't think i'll be much of a contributor, but do as you like ;)
<azonenberg> well if you're interested pm me your googlecode email
<CIA-67> homecmos r81 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<CIA-67> homecmos r82 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<B0101> Oh, CIA logs any changes to the wiki...
<azonenberg_lab> Time to have some fun...
<azonenberg_lab> B0101: There seems to be a little formatting glitch on the EDA tools page - i think you need a blank line after the heading marker for it to format right
<azonenberg_lab> Other than that, good start
<B0101> ok noted
<azonenberg_lab> W00t
<azonenberg_lab> This one looks pretty good
<azonenberg_lab> Gonna try baking it and KOH'ing
<azonenberg_lab> Some residue in areas that should have been lifted off but the hardmask looks undamaged where it should be
<azonenberg_lab> pics coming shortly
<azonenberg_lab> opens 4-inch cassette labeled "Furnace carrier wafer" (aka "cookie sheet")
<CIA-67> homecmos r83 | trunk/lithography-tests/labnotes/azonenberg_labnotes.txt | Updating lab notes for today's experiments.
<azonenberg_lab> Pics uploading in a few
<azonenberg> Uploading...
<azonenberg> Other files in the dir are other shots from the same session but this one is a nice overview of the successful die at 100x
<azonenberg> waits another 45 mins for wafer to bake
<azonenberg_lab> Die is in KOH now, here's hoping it works...
<CIA-67> homecmos r84 | trunk/lithography-tests/labnotes/azonenberg_labnotes.txt | Updating lab notes
<azonenberg_lab> :( didnt work
<azonenberg_lab> hardmask broke off during the etch
<azonenberg> Some pattern was visible though
<azonenberg> So i'm not sure what happened
<azonenberg> Suspecting thermal shock during baking
<B0101> hi
<CIA-67> homecmos r85 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<B0101> Azonenberg: Fixed the problem
<B0101> I am going to find and add more links...
<CIA-67> homecmos r86 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<CIA-67> homecmos r87 | wiki/FreeEDATools.wiki | Edited wiki page FreeEDATools through web user interface.
<CIA-67> homecmos r88 | wiki/FreeEDATools.wiki |
<CIA-67> Edited wiki page Free EDA Tools through web user interface.
<CIA-67> Edited most of the links and edited summary
<B0101> Hi
<B0101> Azonenberg: Did your etch succeed?
<azonenberg> B0101: Not as well as I'd like
<azonenberg> The hardmask cracked during baking and broke off
<azonenberg> But i'm very close
<azonenberg> i think i just need to do slower heat/cool cycles and use a slightly thinner hardmask
<azonenberg> if it's too thick it cracks more readily
<azonenberg> I noticed the first coat was too thin so i did a second
<azonenberg> but the second i spun too slowly and it got way thicker than i had intended
<azonenberg> i overcompensated
<B0101> oh, by the way, i did editing to the Free EDA tools wiki
<B0101> I have got all the links
<B0101> You could take a look to see if my edits were OK.
<azonenberg> I glanced through them an hour or so ago, they look fine
<azonenberg> Kinda busy atm, will hopefully be free later today
<B0101> ok
<bart416> azonenberg, did you already modify an oven so you can control it with a computer?
<azonenberg> bart416: no
<azonenberg> I have a lab oven with a decently accurate thermostat but no custom profile capabilities
<azonenberg> The furnace i am looking at, iirc, has a programmable controller
<bart416> Ah
<bart416> My contraption for reflow is working pretty well I think
<bart416> the temperature control is getting along
<bart416> But it causes pretty big spikes using PWM, so need to figure out a way to fix that
<azonenberg> i see
<azonenberg> I do have a toaster oven that i was planning to turn into a reflow rig
<azonenberg> Just havent done it yet
<azonenberg> wonders how hard it might be to buy some solder balls and make his own FCBGA
<azonenberg> rather than using wire bonding
<azonenberg> if the pad pitch is nice and large it might not be to bad
<azonenberg> too*
<bart416> Did you see those methods to put ICs in flexible flat cables?
<bart416> Or flexible prints?
<bart416> They basically seem to just put them in circuit and solder the traces directly onto it
<azonenberg> You're talking COF (chip on flex)?
<azonenberg> I havent studied it in too much depth
<bart416> Dunno, I've seen a couple of methods when studying methods for reflow soldering
<azonenberg> I just mean COF in particular
<azonenberg> So tonight I'll be running a test using my comb drive mask from the mems-tests directory
<bart416> Don't know if it's that particular method, but the advantages were rather interesting
<bart416> :D
<bart416> How thick is your hardmask now?
<azonenberg> It'll be on <100> and therefore will not be etchable deep enough to work
<azonenberg> But i have more of that and its cheaper
<azonenberg> So i'll test on that and when i get good yields switch to the <110>
<azonenberg> And actually, thickness is TBD lol
<azonenberg> When i spin coat on a blank wafer it's 225nm ish
<azonenberg> But with liftoff its harder to really tell
<azonenberg> The thickness i had in that last image was huge *looks up chart to estimate*
<bart416> Somebody showed something interesting in ##electronics yesterday
<bart416> A DIY electron microscope
<azonenberg> SEM or TEM?
<azonenberg> Or AFM?
<bart416> SEM
<azonenberg> I think i saw that one, was the guy imaging a big nut or something?
<azonenberg> Something large and not getting nearly enough magnification to be useful yet
<bart416> Yeah, it's the same guy, but he later on went to do a grid
<bart416> And was already going into the micrometer range
<azonenberg> Interesting
<bart416> He said he's going to publish his documentation on it on the internet
<azonenberg> Nice
<bart416> So maybe with some luck some nut comes along and makes something you can actually use
<azonenberg> Lol, perhaps
<berndj> btw, what's a good keyword to add when searching for people who do stuff only Big Industry (tm) is supposed to be doing?
<berndj> calling it "homemade" can seem inaccurate
<azonenberg> Yeah, i have no idea
<azonenberg> Makes it hard to find others
<bart416> DIY
<azonenberg> Thats what i used
<berndj> sometimes i have luck just googling the jargon
<azonenberg> Btw - by counting intereference fringes it looks like the hardmask in my last test was something over 800nm thick
<azonenberg> Which explains the cracking
<azonenberg> thats like 4x thicker than it should be
<bart416> wow, 800 nm is really thick
<azonenberg> I did a double coat AND dropped the RPMs
<azonenberg> one or the other is fine, but both is too much
<azonenberg> One layer at max rpm without photoresist in the way gives, as i mentioned, somewhere around 225nm
<bart416> You could probably calculate the thickness of the layers if you bothered with it
<azonenberg> Again all of these values are estimates
<azonenberg> I dont know the refractive index is the thing
<azonenberg> since its spin coated the nubmers are different than for bulk
<azonenberg> its not as dense
<azonenberg> I'm estimating it to be comparable to SiO2, but it isnt
<azonenberg> i could be off by 30% either way
<azonenberg> But it's still way thicker than it should be, that much is certain
<berndj> 800nm already accounting for Ta2O5's highish index of refraction?
<azonenberg> berndj: 800nm assuming SiO2
<azonenberg> Otherwise, it might be more
<berndj> err, less?  as in, you need less Ta2O5 to give the same optical path length?
<azonenberg> Oh, good point
<azonenberg> Sorry about that
<azonenberg> For SiO2 it would be either 890 or 1510 in the thickest part
<azonenberg> I couldnt tell if one spot on the edge was one fringe or two
<azonenberg> And given how high the index is, my previous estimate of 50nm might actually be overkill for what i had in my old tests
<azonenberg> it might be more like 30
<berndj> do you count under white light?
<azonenberg> berndj: Yes
<azonenberg> Halogen microscope lamp
<berndj> i guess your chart is made for broadband light, but in general, fringes show up much more under narrowband light.  CFLs work quite well
<azonenberg> Yeah
<azonenberg> If you want to try giving a better estimate than me, feel free http://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-06-19/S7300900.JPG
<azonenberg> This is actually Ta2Cl10
<azonenberg> before baking
<bart416> I wouldn't worry about it too much, just make sure it's not too thick so it doesn't crack again
<azonenberg> Yeah, thats why i didnt recalculate either
<azonenberg> It didnt seem worth the effort
<azonenberg> Thoguh getting a ta2o5 color chart would be nice if anyone wants to run the math
<bart416> First get it working, then fine tune it
<azonenberg> And yeah
<azonenberg> Tonight i'll be doing some more tests and we'll see what happens...
<azonenberg> I feel like we're getting close
<azonenberg> Once I get lithography of silicon working pretty reliably it opens up a ton of possibilities
<azonenberg> The next big unsolved problem is metal deposition
<azonenberg> Patterning of metal can be done with an HCl : H2O2 : H2O etch which is CMOS compatible and won't diffuse through my photoresist
<azonenberg> I've used it on copper in the past with good results
<azonenberg> And it wont be nearly as difficult as patterning of, say, SiO2 or Si
<azonenberg> Metal deposition can be done by evaporation or sputtering, pretty much
<azonenberg> Both require vacuum
<B0101> hi, back from Breakfast, what have I missed?
<azonenberg> But sputtering needs a much less deep vacuum since you're actually letting inert gas into the chamber
<azonenberg> something like 7E-1 torr vs 1E-6 for evaporation
<azonenberg> Sputtering has its own set of problems, though
<azonenberg> Even if you ignore the need for inert gas supply
<azonenberg> Since you arent pumping down really deep, there may be traces of oxygen
<azonenberg> and nitrogen
<azonenberg> Meaning that you may get oxide/nitride contamination if you are sputtering anything reactive
<azonenberg> vs gold or platinum or another noble metal
<azonenberg> Noble metals, however, are very tough to pattern
<azonenberg> by anything but liftoff
<azonenberg> And liftoff of a sputtered film is difficult because the coating is pretty conformal
<azonenberg> But if we can figure out how to sputter something like aluminum or copper we're in decent shape
<bart416> 10^-6 is in the range of a normal vacuum pump
<azonenberg> Except copper has its own set of problems when used with CMOS
<azonenberg> bart416: Um, i dont think so
<bart416> well, with normal I mean non expensive azonenberg :|
<azonenberg> The lowest i've ever hit with a mechanical pump was 1.2E-1 torr
<berndj> in the old days people made mirrors with some weird amalgam process
<azonenberg> 2 stage rotary vane
<berndj> no vacuum needed!
<azonenberg> A diffusion or turbopump or similar is pretty much necessary to go much deeper
<azonenberg> The best mechanical pump i've ever seen was advertised as hitting 4E-2 torr which is still high for evaporation
<azonenberg> But realistic for sputtering
<bart416> mechanical is normal for you? |
<bart416> The most normal for me is using a water stream to cause negative pressure differential
<azonenberg> bart416: Normal meaning 2-stage rotary vane like http://unitednuclear.com/index.php?main_page=product_info&cPath=28_52&products_id=405
<azonenberg> bart416: Those things cant go below the vapor pressure of water
<azonenberg> I've used them once
<bart416> azonenberg, you're confusing my definitions of normal with yours
<berndj> put a piece of sodium inside as a getter
<azonenberg> Diffusion pumps are very similar but use oil or something with a lower vapor pressure
<bart416> Normal in what sense?
<bart416> first with normal I meant non expensive
<bart416> But you define normal as mechanical and other simple designs
<azonenberg> And $300 isnt that bad for a vacuum pump
<azonenberg> Turbos cost >$5K
<bart416> Mechanical not being normal for me as there are so much sub divisions in it :|
<azonenberg> A diffusion pump, though, can probably be done pretty cheap
<berndj> the diy laser guys sometimes make their own diffusion pumps, iirc
<azonenberg> berndj: Interesting
<berndj> or cryotraps
<bart416> You can probably get one fairly cheaply from an old lab equipment sale
<azonenberg> I've never tried doing a cryopump
<azonenberg> But i imagine it's doable
<berndj> i imagine you can get hold of some liquid N2 fairly cheaply
<bart416> Looks achievable enough if you have access to a lathe
<lekernel> is that a diffusion pump?
<bart416> Yes
<azonenberg> I do, my school machine shop has several manuals and one CNC
<berndj> azonenberg, that H-shape fringe thing i'm looking at, is the fringey bit the Ta2Cl layer?
<azonenberg> berndj: The background is silicon
<azonenberg> The fringes are Ta2Cl10
<berndj> ah.  those edges make it real difficult to count :(
<lekernel> azonenberg: cryopumps are super simple, they're just a bottle of zeoliths frozen with liquid nitrogen
<azonenberg> the active ingredient in Tantalumfilm (solvent is denatured alcohol which has already evaporated)
<azonenberg> Which hydrolyzes to Ta2O5 after baking
<azonenberg> lekernel: I know
<azonenberg> It just means keeping cryogenics around
<azonenberg> one more thing to add to the supplies list
<azonenberg> A diffusion pump might be doable though
<bart416> Liquid nitrogen doesn't come cheap...
<lekernel> there is an article explaining how to DIY them in Amateur Scientist
<lekernel> liquid nitrogen is 10 cents a liter unless you get ripped off
<bart416> You get it at 10 cents a liter?
<bart416> Wow o_O
<berndj> yup
<bart416> Where the hell do you buy it?
<berndj> big industrial users of oxygen have tanks of liquid oxygen
<berndj> at the gas yard :)
<bart416> Only place where I can get it here is a small lab about 5km down the road
<berndj> if you have an interesting story (and you do) you could twist someone's arm to let you "find" some while they aren't looking
<azonenberg> lol
<berndj> you don't really care about purity though; just the low temp
<bart416> lol
<azonenberg> True, since i'm not exposing it to the chamber directly
<azonenberg> Just through conduction
<berndj> don't lol, that's how a model rocketry guy i know got his oxidizer!
<azonenberg> o_O
<bart416> berndj, mind you these are the same guys that were willing to sell me nitroglycerine...
<berndj> now you made me lol
<bart416> Not much but still o_O
<bart416> You know where you might find some info on building a good vacuum pump
<bart416> All those fusor project websites
<bart416> You need a pretty good vacuum pump for that
<azonenberg> Yeah, good point
<berndj> hmm, i vaguely recall there being a yahoo group specifically for vacuum stuff
<azonenberg> I was going to save that until I had lithography working, but if anyone wants to do the research and post info to the wiki that'd be great
<azonenberg> Evaporation is a lot easier to do than sputtering and also has better liftoff profiles
<azonenberg> And i'd prefer it, but i need a way of getting deep vacuum
<berndj> does silver count as "noble"?
<azonenberg> berndj: I dont think so
<azonenberg> gold, platinum, ruthenium
<azonenberg> palladium
<berndj> as in, can you etch silver
<azonenberg> I believe so
<azonenberg> Just not sure with what
<bart416> btw, this is one of the results for DIY vacuum pump: http://tubedevices.com/alek/pwl/lc1d/homemade_nixie_tubes.pdf
<berndj> if you want to / have to avoid vacuum (for now), could that silvering process + electroplating help?
<azonenberg> berndj: No, i have other deposition needs that cant be done without vacuum
<azonenberg> For example, polysilicon
<berndj> ah, ok
<azonenberg> I have five silicon crystals suitable for evaporation (5mm cubes) sitting around waiting for a suitable chamber, pump, etc lo
<bart416> wtf, somebody is building a linac in his garage o_O
<berndj> i thought for polysilicon you run some silane (SiH4) CVD type process?
<berndj> yup bart416
<azonenberg> berndj: CVD is the most common method
<azonenberg> But you can evaporate or sputter too
<bart416> That sure as hell beats the fusor guys
<azonenberg> Its just less popular for mass production
<bart416> But you aren't doing mass production...
<azonenberg> Exactly
<azonenberg> Hence sputtering or evaporation are preferred
<azonenberg> i want to avoid keeping SiH4 around at all cost :p
<azonenberg> A small amount of argon for sputtering, if i cant avoid it, ok
<bart416> Yeah, but argon isn't that expensive all things considered
<bart416> Unless if you want enough for the rest of your life
<azonenberg> I'm more concerned about the safety implications of keeping giant cylinders of potentially toxic gases in the living room :P
<azonenberg> A small 20 ft^3 lecture bottle of argon i can handle
<bart416> Argon isn't toxic :P
<azonenberg> but SiH4 is both flammable and toxic and i dont want it around
<bart416> heh
<azonenberg> Argon is inert and pretty harmless
<bart416> Maybe you can use helium, that'd be even cheaper
<azonenberg> Especially if the cylinder is small enough that hypoxia from a leak isnt a serious concern
<azonenberg> bart416: for sputtering you need a reasonably heavy gas
<azonenberg> neon or argon work best
<berndj> something's wrong in http://en.wikipedia.org/wiki/Silicon - check boiling point vs vapour pressure table.  boiling point listed as 2628K, but 100kPa vapour pressure at 3537K???
<B0101> Bye guys, off to work!
<bart416> berndj, go and get a good periodic table, don't use wikipedia!
<berndj> i think even a big cylinder of argon won't displace enough of the air in your room to cause a problem
<berndj> maybe the tiniest of bathrooms
<bart416> the only way I see it cause a problem if it releases its entire contents at once
<azonenberg> berndj: 20 ft^3 isnt a concern
<azonenberg> I just would be cautious about one of the several-hundred-ft^3 ones
<bart416> But then it's probably going to create some extra ventilation holes to compensate for that
<azonenberg> Leaks of those (especially N2) have been known to make a decent sized room hypoxic
<azonenberg> the trouble with inert gases is that you dont realize you're out of air until you keel over
<azonenberg> vs CO2 you notice immediately
<berndj> bart416: door-sized ventilation holes?
<bart416> berndj, I'd say that depends on the material the wall's made from :')
<azonenberg> But in a nice large room (20-30 feet across) 20 ft^3 would be harmless even if released all at once
<bart416> In a nice large room worst case scenario you'd get a little bit light headed
<berndj> 20ft room would be maybe 3200ft^3... displacing even several hundred ft^3 shouldn't kill you
<bart416> Damnit stop working in non SI units, it's confusing o_O
<berndj> air is 20% O2, you'd need to halve that to kill.  funny, was just reading about fire suppression
<bart416> <3 Halon :P
<bart416> It's a shame they banned it
<bart416> Best fire extinguishers ever :S
<bart416> Those regular ones in cars are crap
<bart416> You can't even put out a small camp fire with those
<bart416> Anyway 'nite