| wpwrak | in the end, you'll have a joystick with which you direct the death ray that picks off those last molecules that resisted everything else you threw at them ;-) | 00:21 |
|---|---|---|
| wpwrak | azonenberg: you guys lost me at KOH vs. HF. i live in HCl+H2O2 stone age. what do these critters do ? i suppose at least one of them is an etchant, but does this make the other ? | 00:22 |
| azonenberg | wpwrak: HF is hydrofluoric acid, which eats | 00:25 |
| azonenberg | SiO2 (glass) and related materials | 00:25 |
| azonenberg | But not silicon or polymer materials | 00:25 |
| wpwrak | sound like nasty stuff :) | 00:26 |
| azonenberg | HF is quite nasty, thats why i work with 2% solution and am still paranoid with double gloves, a face shield, etc :P | 00:26 |
| azonenberg | Overkill considering the stuff in this concentration is household rust remover | 00:26 |
| wpwrak | i usually consider glass and ceramics as my final barrier ;-) | 00:26 |
| azonenberg | But i've seen what the strong stuff can do | 00:26 |
| azonenberg | My photoresist is a polymer that dissolves in a weak solution NaOH (household lye) when it's been exposed to light | 00:26 |
| azonenberg | UV in particular | 00:27 |
| azonenberg | So you shine UV through your mask onto the resist, then develop | 00:27 |
| azonenberg | Then you can use HF to eat away the glassy layer under it | 00:27 |
| azonenberg | but only where light hit the mask | 00:27 |
| wpwrak | (rust remover) hmm, interesting. | 00:27 |
| azonenberg | It's rare, most rust remover is phosphoric acid | 00:27 |
| azonenberg | But Whink brand is HF based | 00:27 |
| azonenberg | KOH is potassium hydroxide (caustic potash) which will eat silicon | 00:27 |
| azonenberg | It also attacks photoresist so i need the Ta2O5 glass layer as a mask | 00:28 |
| azonenberg | i.e. pattern hardmask with photoresist, then pattern silicon with hardmask | 00:28 |
| azonenberg | using two etch steps | 00:28 |
| azonenberg | The nice thing about KOH is that it's sensitive to the bond structure in the silicon crystal | 00:29 |
| azonenberg | It eats nearly 100x faster along one axis than the other one | 00:29 |
| azonenberg | So by choosing the angle that you cut the wafer vs the bond planes you can get almost no etching (surface on the <111> vector), 57 degree sloped sidewalls (surface on the <100> vector), or vertical sidewalls (surface on the <110> vector) | 00:30 |
| wpwrak | brr. messy. i kinda liked whatshername's transistor-making process you once mentioned. obviously, the process control roles are reversed there, but it seems that isn't nothing too horrible to do | 00:30 |
| azonenberg | Jeri used HF | 00:31 |
| azonenberg | Same concentration as I am - 2% from Whink rust remover | 00:31 |
| azonenberg | The main difference is she was doing patterning by hand with electrical-tape masks etc | 00:31 |
| wpwrak | yeah ;-) | 00:31 |
| azonenberg | I'm doing real lithography at several-micron scales | 00:31 |
| azonenberg | And i'm not to the point i can do transistors at this scale by far | 00:31 |
| azonenberg | The first step is MEMS | 00:32 |
| azonenberg | Build a comb drive | 00:32 |
| azonenberg | And before that, basic 2D engraving in Si | 00:33 |
| azonenberg | Shallow etching, 10 microns or so | 00:33 |
| azonenberg | just characterizing the process | 00:33 |
| wpwrak | i don't know much about mems or their use. i have some ideas what a transistor can be good for, though :) one problem i'd envision is just connectivity. that's some more layers. | 00:33 |
| azonenberg | Connectivity, well | 00:33 |
| azonenberg | Etching metal is a solved problem, so is alignment | 00:33 |
| azonenberg | The unsolved problem is how to get the metal there in the first place | 00:33 |
| wpwrak | yup | 00:33 |
| azonenberg | there are several deposition processes (sputtering and evaporation are the two big ones) but both need high vacuum | 00:34 |
| wpwrak | which requires some alchimist's lab in paris | 00:34 |
| azonenberg | Lol, or something i build here in new york | 00:34 |
| azonenberg | The first step will be etching these patterns http://i.imgur.com/VDW36.png just a few microns deep | 00:34 |
| wpwrak | and people are worred about cern's black holes eating geneva ;-) | 00:35 |
| azonenberg | Lol | 00:35 |
| azonenberg | Black is informational only (not on the actual mask) | 00:35 |
| azonenberg | The outer disk around each pattern is the field of view of my exposure system (about 500 microns) | 00:35 |
| azonenberg | Blue areas are masked off, white is to be etched | 00:36 |
| azonenberg | Everything outside the disk is not etched | 00:36 |
| wpwrak | damn small. i still kinda like the idea of a dual BR direct exposure system. | 00:36 |
| azonenberg | I'm still thinking of direct write but not for exposure on the wafer | 00:36 |
| azonenberg | it'll be used for making metal-on-glass masks | 00:37 |
| azonenberg | that are then used in my projection system | 00:37 |
| wpwrak | if you have it, why not use it for everything ? | 00:37 |
| azonenberg | Because it can pattern but has little alignment capability | 00:37 |
| azonenberg | unless you build it in a far more advanced way | 00:37 |
| azonenberg | The idea was, stick mask blank into the system | 00:37 |
| azonenberg | zero it *somewhere* on the blank | 00:37 |
| azonenberg | expose, develop, etch | 00:37 |
| wpwrak | hmm. i'd try to align with perhipheral features. edges, holes made for that purpose, whatever. | 00:38 |
| azonenberg | now you have your mask, 100nm of (say) nickel plated on glass | 00:38 |
| azonenberg | With 50 micron (for example) features | 00:38 |
| azonenberg | Feed that into my current exposure system | 00:38 |
| azonenberg | Reduce 10x | 00:39 |
| azonenberg | You now have 5um features and a 2mm FOV, which is enough for a pretty good sized die | 00:39 |
| azonenberg | It'd be enough to build a 4004 i think | 00:39 |
| wpwrak | 2 mm is plenty, yes | 00:39 |
| azonenberg | 500um is FOV with 40x objective | 00:39 |
| azonenberg | 2mm is FOV with 10x | 00:39 |
| azonenberg | But that also means my feature size grows 4x so the only way to prevent that is to make the mask 4x smaller | 00:40 |
| azonenberg | i.e. 50um half-pitch vs 200um (the limit of my printer) | 00:40 |
| azonenberg | I could even hit 5mm if i used the 4x obj but that'd be pushing it | 00:40 |
| wpwrak | or just use direct writing ;) | 00:40 |
| azonenberg | Because i'd need 20um features on the mask | 00:40 |
| azonenberg | And those would be so small i wouldn't be able to see them at 40x magnification easily and get good alignment | 00:41 |
| azonenberg | 100x is about the minimum to get micron-level alignment | 00:41 |
| azonenberg | And like i said, i'd love direct write onto the wafer | 00:41 |
| azonenberg | I just think it's beyond trhe scope of a rev 1 process | 00:42 |
| wpwrak | whatever rev 1 may be :) for me, your inverted scope is an excellent hack. not only for the idea itself, but also because it breaks down one of those imaginary barriers. | 00:43 |
| azonenberg | Exactly | 00:43 |
| azonenberg | That was the single biggest unsolved problem for me, my group at RPI was puzzling over lithography and mask alignment for months | 00:43 |
| azonenberg | thinknig about building an optical column from scratch | 00:44 |
| azonenberg | Then i realized we already had one, problem solved | 00:44 |
| wpwrak | but for a more dependable process, it seems to me that BR drives are an excellent opportunity. they have the resolution and, thanks to mass-market volumes, they're relatively cheap. | 00:44 |
| azonenberg | Yeah, I fully agree with you there | 00:44 |
| azonenberg | It's just something that should be saved until the rest of the process is somewhat more mature | 00:44 |
| azonenberg | If you want, i can set you up with access to the project http://code.google.com/p/homecmos/ so you can hack on the wiki and start throwing thoughts in there | 00:45 |
| wpwrak | (building an optical column) looks like one of those problems that seem ridiculously simple - once you've solved them ;-) | 00:45 |
| azonenberg | Exactly, once you have all the numbers and plans anybody can go build it | 00:45 |
| azonenberg | It's the engineering that's hard | 00:45 |
| azonenberg | And, once you've built it, the calibration | 00:45 |
| azonenberg | getting everything precisely in focus | 00:45 |
| wpwrak | i have a strong belief in the law of large numbers ;-) | 00:47 |
| azonenberg | Lol | 00:47 |
| azonenberg | And this is a solved problem with the microscope - which is a pretty nice piece of glass for the price | 00:47 |
| azonenberg | The only big problem is chromatic aberration at higher powers | 00:47 |
| azonenberg | But when using monochromatic light from an LED? Non-issue | 00:47 |
| wpwrak | the microscope looks more like a mid-way point. it solves the problem at hand, showing that it can be solved, but it suffers many limitations as well (FOV, for one) | 00:48 |
| azonenberg | Correcty | 00:49 |
| azonenberg | Hence why it's a rev 1 process | 00:49 |
| wpwrak | besides, it's not really "cheap". while BR is, by and large. | 00:49 |
| azonenberg | The big problem, like i said, with BR is alignment | 00:49 |
| azonenberg | It's going to have to be done like they do with steppers | 00:49 |
| azonenberg | you have purpose-built alignment marks around the edge of the die | 00:49 |
| azonenberg | that it calibrates off | 00:50 |
| wpwrak | i stil think you can just use opportunistic alignment. find any features, and align to them. | 00:50 |
| azonenberg | Maybe for rev 3? But it'd be tricky | 00:50 |
| azonenberg | This would be quite the hack if we pulled it off though | 00:50 |
| azonenberg | Direct write laser lithography system with 5um or better features | 00:50 |
| wpwrak | you only care about repeating what you did before. but there's no absolute origin or orientation. | 00:50 |
| wpwrak | indeed. Intel@Home ;-) | 00:51 |
| azonenberg | Good point, only alignment matters | 00:51 |
| azonenberg | But what about if you have a nearly blank mask? | 00:51 |
| azonenberg | Also, when you say "align to them" | 00:51 |
| azonenberg | The detector is easy | 00:52 |
| azonenberg | But how do you see it? | 00:52 |
| azonenberg | Illuminate with the laser? Bear in mind every laser pulse punches a hole in the photoresist | 00:52 |
| wpwrak | i'd align with the chip/fragment. or if that doesn't work, make a hole and align with that. | 00:52 |
| wpwrak | (not sure about the cleaning, though) | 00:52 |
| azonenberg | Hole meaning drilled? | 00:52 |
| azonenberg | Waaay too imprecise | 00:52 |
| wpwrak | yes | 00:52 |
| azonenberg | Do you have any idea how small five microns is? | 00:52 |
| azonenberg | Hint, typical human hair is 20um across | 00:53 |
| azonenberg | Let's say you drill a hole 1mm across | 00:53 |
| wpwrak | you only care about finding the same edge several times again | 00:53 |
| azonenberg | You need to be able to localize to within 1/50 of the hole diameter | 00:53 |
| azonenberg | And you'd need >1 hole to get rotation locked down as well as position | 00:53 |
| azonenberg | It'd just be too imprecise | 00:54 |
| wpwrak | sure. make as many holes as you want. the first one is expensive, the rest is free ;-) | 00:54 |
| azonenberg | lol | 00:54 |
| azonenberg | the other thing is, in MEMS, puncturing the die can be problematic | 00:54 |
| azonenberg | You might need a big piece for a heatsink or whatever | 00:54 |
| azonenberg | It just strikes me as a really bad idea | 00:54 |
| azonenberg | Whereas if the first exposure etched alignment marks into th esurface | 00:55 |
| azonenberg | At 5um pitch | 00:55 |
| azonenberg | We could then see those markings and align future stages to them | 00:55 |
| wpwrak | you don't need the exact position relative to the hole center or such. all you need is an edge you can detect accurately (with significantly less than infinite tries ;). once you have that, you can always reuse that edge. | 00:56 |
| azonenberg | The other thing is, silicon fractures along cleavage planes | 00:56 |
| azonenberg | A hole is a potential fracture point | 00:56 |
| wpwrak | (mems) yeah, dunno about mems. | 00:56 |
| azonenberg | And, on top of that, each edge of the hole is going to be (at the microscale) broken along one of the cleaveage planes | 00:56 |
| wpwrak | could you try to cut/mill a straight line ? | 00:57 |
| wpwrak | you'd of course end up with a jagged edge, because you won't match the substrate's orientation | 00:58 |
| azonenberg | Well, the substrate will have at least one edge (or a flat for a wafer) parallel to a cleavage plane | 00:59 |
| azonenberg | you'd align theta to that | 00:59 |
| azonenberg | So you're aligned to the crystal structure | 01:00 |
| wpwrak | one degree of freedom solved :) | 01:00 |
| azonenberg | (for the first level) and then etch your main pattern plus alignment markings | 01:00 |
| azonenberg | crosses, vernier scale, etc | 01:00 |
| azonenberg | Around the edges | 01:00 |
| azonenberg | Then the next level just aligns to them | 01:00 |
| wpwrak | doesn't sound too bad. you still need at least two edges to align to, though for each step. | 01:01 |
| azonenberg | No, you need one edge for the first step since you know which plane it's on a priori | 01:02 |
| azonenberg | From there on, you have a cross at each side of the die | 01:02 |
| azonenberg | Align x/y to the center of them | 01:02 |
| azonenberg | and theta so that the lines are parallel to your axes | 01:02 |
| azonenberg | google "byu contact aligner" for Bringham Young Universtity's doc on their manual mask aligner | 01:03 |
| azonenberg | We just need to design an automated system that can read those marks | 01:03 |
| wpwrak | that's your microscope process. but what about the BR process ? there's not much a priori there. the machine has to discover everything on its own, each time the die is inserted. | 01:03 |
| azonenberg | no, you misunderstand | 01:03 |
| azonenberg | You stick the die into it, it scans the edge | 01:04 |
| azonenberg | Determines the crystal orientation (if the first run) | 01:04 |
| wpwrak | yes | 01:04 |
| azonenberg | i.e. you tell it "this is a <100> wafer, align X axis to a <111> plane | 01:04 |
| azonenberg | Then it'll center your pattern on the fragment approximately | 01:04 |
| azonenberg | Future exposures will scan the edge, determine the approximate center (to within 100um or so, really coarse) and then locate the alignment crosses | 01:04 |
| azonenberg | which it will use for the real fine alignment | 01:05 |
| azonenberg | The problem is that we need to figure out how to see those marks | 01:05 |
| azonenberg | and get data that a machine vision system can use to determine the actual position of the die and adjust the stage accordingly | 01:05 |
| wpwrak | ah, you're trying to identify features on the die | 01:06 |
| azonenberg | Correct | 01:06 |
| azonenberg | Its the only way to get precise alignment | 01:06 |
| azonenberg | below a hundred microns or so | 01:06 |
| wpwrak | i was thinking of just (re-)identifying the die's shape | 01:06 |
| azonenberg | Not good enough | 01:06 |
| azonenberg | Some of my substrates are precise rectangles 1cm square | 01:06 |
| azonenberg | you cant tell orientation from that | 01:06 |
| azonenberg | http://www.cnf.cornell.edu/cnf_process_photo_step_align.html | 01:07 |
| azonenberg | Scroll down to the bottom | 01:07 |
| wpwrak | you don't need a simple euclidian shape. i think it should be sufficient to identify the chaotic edges. | 01:08 |
| azonenberg | Take it from someone who's done a good amount of machine vision | 01:08 |
| azonenberg | Simple euclidean shapes are waaaay easier to work with | 01:09 |
| azonenberg | And you can get better precision with them | 01:09 |
| wpwrak | oh, fiducials are great - if you have them ;-) | 01:09 |
| azonenberg | What do you mean? | 01:09 |
| wpwrak | i'd add them just for fun. and check them if anything goes wrong ;-) | 01:09 |
| azonenberg | The first mask level is positioned approximately | 01:09 |
| azonenberg | Adds marks for all subsequent alignment steps | 01:10 |
| azonenberg | All of the others lock onto those marks | 01:10 |
| wpwrak | well, our problem is that it's easy to write with high precision and within a large area, but it's hard to see things with high precision within a large area | 01:10 |
| azonenberg | Unless you're built into a microscope | 01:11 |
| wpwrak | where "see things" means a generalized kind of vision | 01:11 |
| azonenberg | You need a camera of some sort, which means an optical column | 01:11 |
| azonenberg | I still think the best option is direct write with little to no alignment onto a mask blank | 01:11 |
| azonenberg | followed by manual alignment using the microscope | 01:12 |
| wpwrak | now, there are some things you can see easily, e.g., whether an edge obscures a narrow beam or not | 01:12 |
| azonenberg | But there's another problem | 01:12 |
| azonenberg | Drift | 01:13 |
| wpwrak | drift of what ? | 01:13 |
| azonenberg | As you pan from one side of the die to the other | 01:13 |
| azonenberg | Alignment will gradually be lost | 01:13 |
| azonenberg | due to imprecisions in the motors etc | 01:13 |
| azonenberg | I suspect you'll need to realign periodically during a long run | 01:13 |
| azonenberg | Especially if stepping multiple patterns on multiple dies on one wafer | 01:13 |
| azonenberg | IOW, if i move 1000um right and 1000um left | 01:14 |
| azonenberg | I won't be exactly where i started | 01:14 |
| wpwrak | if you lose alignment within the die, you're probably screwed. well, unless you can model the loss accurately :) | 01:14 |
| wpwrak | yeah, big wafers would be an issue. i can see that. | 01:15 |
| azonenberg | Well, i think we can all agree that the first draft of the bluray system will have little to no visio ncapability | 01:15 |
| wpwrak | but perhaps that's a version 2 problem ? :) | 01:15 |
| azonenberg | and just be direct patterning on mask blanks | 01:15 |
| azonenberg | Vision is a v3 problem | 01:15 |
| azonenberg | v2 is where we introduce laser direct write | 01:15 |
| azonenberg | v1 is transparencies on microscope | 01:15 |
| wpwrak | v3 then :) | 01:15 |
| wpwrak | i think you still need simple vision for lowering the requirements for v2. 2 x BR player plus a photo diode is still a lot more accessible than a camera-ready microscope | 01:19 |
| kristianpaul | hacking a camera you mean? | 01:21 |
| wpwrak | (fiducials) looking at the patterns, i wonder if they didn't exaggerate perhaps just a little (towards the end) ;-) | 01:22 |
| kristianpaul | i wonder what can you do inverting some lenses on a cheap canon camera, if already on a cheap webcam is not that bad for DIY scopes~ | 01:22 |
| azonenberg | Exaggerate? What do you mean | 01:23 |
| azonenberg | When you're trying to get alignment down to a few nm it's kinda important | 01:23 |
| wpwrak | kristianpaul: ah, i think we covered the "mass market camera" side already :) the somethat disappointing result is that they don't go far enough (sample size = 1, so take this for whatever it means :) | 01:24 |
| azonenberg | +/- 150nm for example | 01:24 |
| wpwrak | azonenberg: (exaggerated) http://www.cnf.cornell.edu/image/stepper alignment global with microscope overlay.jpg | 01:24 |
| azonenberg | what about it? | 01:25 |
| azonenberg | You need to be able to start from any angle and determine the correct position | 01:25 |
| wpwrak | what you really need is an edge. two for 2D alignment. i even get 45 deg crosses, but stepped bars, extra-narrow edges of rectangles with rounded corners ? :) | 01:26 |
| azonenberg | The rounded corners are an artifact of the etch probably, and the long bars are for theta alignment | 01:27 |
| azonenberg | you need a baseline that's good enough to find the other alignnment mark across the wafer | 01:27 |
| azonenberg | then the small stepped bars are probably a vernier scale | 01:27 |
| wpwrak | okay, but that's more process optimizations then | 01:28 |
| azonenberg | for alignment to below the smallest feature scale you can etch | 01:28 |
| azonenberg | i know that the stepper the guys at work are using (not the same model as the one on this page) has a vernier | 01:28 |
| wpwrak | hmm. still looks suspiciously like a process designed for human vision to me. | 01:32 |
| wpwrak | perhaps for some truly advances computer vision as well. but just to find a few edges ? | 01:32 |
| azonenberg | It's advanced vision | 01:33 |
| azonenberg | Those things cost $40M + | 01:33 |
| azonenberg | Lol | 01:33 |
| azonenberg | For my process i envision using a much simpler alignment strategy | 01:33 |
| azonenberg | Probably just a couple of crosses at 0/90/180/270 degrees | 01:33 |
| wpwrak | i guess that's cheap as far as such things are considered ;-) | 01:33 |
| wpwrak | i'd just let the damn machine scan the ragged edge, that's tens of thousands of data points. if you can't mine a decent position from that, what else can you do ? ;-) | 01:35 |
| azonenberg | The thing is that not all of the dies have ragged edges | 01:35 |
| azonenberg | http://www.mtixtl.com/sisinglecrystalsubstrate110orn10x10x05mm1spundoped.aspx | 01:35 |
| azonenberg | 1cm square | 01:36 |
| wpwrak | hey, if it's perfect, even better ;-) find the edge on X, find it one Y, and you're done for the day ;-) | 01:36 |
| azonenberg | Thats the thing, the edges are accurate to maybe 10um or 25um | 01:37 |
| wpwrak | (well, twice each - unless you eliminated rotation as well :) | 01:37 |
| azonenberg | i need alignment to 5um | 01:37 |
| azonenberg | and you still need optical to determine which way is up | 01:37 |
| wpwrak | ah, so there's the great return of the ragged edge then :) | 01:37 |
| azonenberg | Also, http://www.laserlab.com/plotprices.php | 01:37 |
| azonenberg | This is the price to beat, you can get commercial photoplots for $34 for a 12x18 inch film sheet | 01:38 |
| azonenberg | at 4000 DPI | 01:38 |
| azonenberg | Feature sizes on the masks are maybe 25 or 50 um | 01:38 |
| azonenberg | if not better | 01:38 |
| azonenberg | And 12x18 inch film is enough for a complete mask set | 01:38 |
| azonenberg | several times over | 01:39 |
| azonenberg | considering that my exposure system can handle up to a 2cm square mask | 01:39 |
| wpwrak | comparing price is tricky. since we're talking about extremely low duty cycles, almost all of the cost is in up-front investment | 01:39 |
| azonenberg | Correct | 01:39 |
| azonenberg | I'm just saying, unless you are making a lot it may be the case that masks are not viable to homebrew | 01:40 |
| azonenberg | On the other hand, the cost of wafer fab is insanely high and homebrew is the only affordable way to experiment | 01:40 |
| wpwrak | i think direct write is a lot more exciting. also because it reduces the number of steps. each step increases the probability of failure. | 01:41 |
| azonenberg | True | 01:42 |
| azonenberg | I think I am going to place a single order from these guys over the summer | 01:42 |
| azonenberg | Include a bunch of test patterns etc | 01:42 |
| azonenberg | And see how small i can actually reach | 01:43 |
| azonenberg | IOW my current lambda is limited by printer resolution | 01:43 |
| azonenberg | So if i have a super high res mask i can push the rest of the process to its limit | 01:43 |
| wpwrak | sounds like a good plan. if there's something you can already get industrially made, even better | 01:43 |
| azonenberg | I'll do the CAD myself since i want to know all of the details of the mask layout | 01:44 |
| azonenberg | $35 plus shipping for 12x18 inches is like 100 test patterns | 01:44 |
| azonenberg | heck, for scale | 01:44 |
| azonenberg | $35 is the cost of a 4-inch wafer | 01:44 |
| wpwrak | the price is certainly affordable enough. well, if you're in the US. seems they don't even do international. | 01:46 |
| azonenberg | They do canada and mexico | 01:46 |
| azonenberg | not sure about overseas | 01:46 |
| wpwrak | does the panama channel make Argentina overseas ? ;) | 01:47 |
| azonenberg | No idea, they just mentioned canada and mexico as being extra fees for shipping etc | 01:47 |
| azonenberg | The very-high-res is $52 | 01:49 |
| azonenberg | Line widths of 12.7um for axially aligned and 25um for diagonal | 01:49 |
| azonenberg | The normal is limited ot 38um for axially aligned and 75 for diagonal | 01:49 |
| wpwrak | line width = resolution * 2 ? | 01:56 |
| wpwrak | no, wait | 01:56 |
| wpwrak | units 1mil/4 micron -> 6.35 | 01:56 |
| wpwrak | (for 4000 dpi) | 01:57 |
| wpwrak | your factor would be dpi*6 | 01:58 |
| azonenberg | Yeah, looks like it | 01:59 |
| azonenberg | so 6pix is the smallest line they can reliably resolve | 01:59 |
| azonenberg | And my printer is 1200 DPI = 21um per pixel | 02:00 |
| azonenberg | times 6 pix = 127 microns | 02:00 |
| azonenberg | 150 is the smallest i've actually tried doing, but 200 is the smallest that gives goodr results last time i tried | 02:01 |
| azonenberg | Actually no, that explains it | 02:01 |
| azonenberg | The printer is 600dpi, not 1200 | 02:01 |
| wpwrak | 5 pixels/line then. still a lot. but okay, considering rounding errors, blur, and all that | 05:41 |
| lekernel | what's a BR drive? | 08:52 |
| lekernel | btw this paper http://www.physics.rutgers.edu/ugrad/387/388s06/film_deposition/Musgraves05.pdf uses direct write with a DLP, which solves the alignment problem nicely | 08:56 |
| lekernel | http://www.youtube.com/watch?v=E0yaGF10Kp8 | 09:04 |
| lekernel | "The patterning of this actuator was done by synchrotron x-ray lithography" lol why? | 09:05 |
| lekernel | it's 30 micron | 09:05 |
| [florian] | lekernel: blu-ray ? | 10:00 |
| lekernel | ah, yeah probably | 10:01 |
| [florian] | morning btw :) | 10:02 |
| lekernel | http://www.public.asu.edu/~aomdw/GLASS/DIFFUSION_PUMP.html | 10:31 |
| lekernel | http://www.cientificosaficionados.com/tbo/difusion/difusora1.htm | 10:50 |
| wpwrak | (BR drive) yes. the idea is to make a direct high-resolution writer from the head assembly of two Blu-Ray readers: one that provides laser and movement in the X direction, and other to move the target in the Y direction. | 11:05 |
| lekernel | roh: how are the rc3 cases going? | 13:48 |
| kristianpaul | lekernel: had you made some tests with OpenCV and mm1? | 16:00 |
| lekernel | no | 16:01 |
| kristianpaul | or and idea where to start with, i think i can econrage a univesiry student to take a look.. | 16:01 |
| kristianpaul | ok | 16:01 |
| kristianpaul | or you have own plans for "Open Vision" on mm1 may be? | 16:01 |
| lekernel | nope | 16:05 |
| kristianpaul | :D ok | 16:06 |
| --- Sun May 22 2011 | 00:00 | |
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