#homecmos IRC log for Saturday, 2011-08-27

azonenbergnathan7: ping04:24
azonenbergI ran a test of parallel lines on the 5um process04:25
azonenbergNot entirely successful, my exposure lamp burned out halfway through the run so it underexposed :P04:25
azonenbergbut i decided to develop and etch anyway to see what i got04:25
azonenbergNowhere near all of the pattern came out but i did demonstrate optical resolution adequate to clearly separate the lins04:26
azonenbergpic following in a bit04:26
CIA-67homecmos r116 | trunk/lithography-tests/labnotes/azonenberg_labnotes.txt | Today's lab notes05:03
azonenbergLatest test on the 5um process05:35
azonenbergNot exactly successful, these are supposed to be unbroken lines05:35
azonenbergBut it demonstrates i have the optical resolution to hit 5um05:35
azonenbergi just need to improve the develop/etch process05:35
azonenbergA lot :P05:35
azonenbergswkhan: check out the link above05:37
azonenbergthis is what i'm working on in my living room fab05:37
azonenbergthe 5um process is under active development but isnt yet feasible, the 20 gives reasonably good results but i still have some glitches in my exposure system05:38
nathan7azonenberg: pong07:58
azonenbergtoday's test run07:59
azonenbergoveretched and underexposed but does demonstrate adequate resolution07:59
azonenbergthe 5um process is clearly not ready for prime time though lol07:59
azonenbergthese are, even so, the smallest structures i've made to date07:59
azonenbergnote the scale bar07:59
azonenbergnominally 5.29 micron half pitch08:00
azonenbergthey were theoretically 5.29 lines and 5.29 trenches but as you can see i overetched08:01
azonenbergso the trenches got bigger and the lines got destroyed08:01
nathan7It's a start08:01
nathan7..don't you have this "wait, whoa, I can _MAKE_ _FIVE_ _MICROMETER_ _STRUCTURES_"08:02
nathan7every once in a while?08:02
nathan7I have that with 3D printers08:02
nathan7every once in a while, I go like "wait, WHOA, I can _PRINT_ _OBJECTS_"08:02
nathan7azonenberg: :D08:05
azonenbergand lol, i have that sometimes with all kinds of projects08:05
azonenbergThis gives you a better idea of the devastation caused by the underexposure http://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-08-26/5h10_002_annotated.jpg08:06
azonenbergthe entire circular field should have had grating in it :P08:06
azonenbergthat's the FOV of my system08:07
azonenbergAnother potential problem is that i am testing on a decently thick copper layer08:08
azonenbergYou normally dont think of a micron as being thick :P08:08
azonenbergBut when you're trying to do 5um features in it08:08
azonenbergusing a *wet etch*08:08
azonenbergrather than RIE08:08
azonenbergit becomes problematic08:08
azonenbergthis is comparable to doing around a 150um PCB trace in 30um copper08:09
azonenbergDoable, but requires careful process control08:09
azonenbergthe shiny areas are the only part of the lins that weren't at least somewhat attacked08:09
azonenbergagain, severe overetch08:09
azonenberghttp://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-08-26/5h10_008_annotated.jpg is the side of the exposure field showing the edge of the etched area08:10
azonenberghttp://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-08-26/5h10_012_annotated.jpg is the edge of the die08:10
azonenbergthe copper doesnt quite go all the way to the edge because some of it chipped off when i cleaved the die off the wafer (coating was done before separation of dies)08:10
azonenberghttp://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-08-26/5h10_014_annotated.jpg is another corner shot08:11
azonenbergThat last pic is cool because it's showing submicron features lol08:12
azonenbergnot created by me, but present on the edges nonetheless08:12
azonenbergi've been looking at some of the rough bumps along the edge and it looks like i'm able to clearly resolve points around 600nm apart08:14
azonenbergi'm looking to see if there are any smaller features i can find08:14
azonenbergto enahance resolution i turned off the red/blue channels which eliminates any chromatic aberration08:15
azonenberghmm, one of the pinholes near the bottom left of the film looks to be around 350nm wide08:15
azonenbergthe crack on the middle left is around 400ish08:16
azonenbergSo do you know what that means?08:16
azonenbergIt means my optics are good enough for submicron resolution if i had a mask that was fine enough08:18
azonenbergi could potentially hit say 500nm with these lenses if i had a fine enough mask08:18
nathan7azonenberg: ..awesomesauce08:19
azonenbergThere are of course some downsides08:19
azonenbergFirst off, it'd be immersion lithography08:19
azonenbergWhich would mean i'd have to clean oil off the die after exposure before developing08:20
azonenbergwithout scratching anything08:20
azonenbergso i'd need a solvent/surfactant that dissolves or emulsifies my immersion medium without harming photoresist etc08:20
azonenbergsecond is that the FOV of my 100x objective is around 160 um :P08:20
azonenbergso that'd be the maximum die size lol08:21
azonenbergRealistically though, i do intend to attempt that soon08:21
azonenbergi have a selection of immersion oils from Ted Pella inbound that i'm gonna play with and see which gives good results08:21
azonenbergAnd lol, are any of you guys among the 8 fans of immersion litho on facebook other than myself?08:22
nathan7I sould08:23
azonenbergMost semiconductor people use water for immersion but i'd need a water immersion objective so for now i'll be using normal microscope immersion oil on my oil lens08:23
azonenbergthere are a lot of highly technical topics on fb that have zero or a handful of fans lol08:24
azonenberglike Ta2O508:24
azonenbergi'm the only fan https://www.facebook.com/pages/TantalumV-oxide/11662823838500308:24
--- Sun Aug 28 201100:00

Generated by irclog2html.py 2.9.2 by Marius Gedminas - find it at mg.pov.lt!