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>> Good morning everyone and welcome to. The mic technique of an artist and it's a pleasure to meet you all or the cynic technical women are sorry for the slide later this morning just quickly I want to share about our scenic program that is funded by n.s.f. and the scenic is one among the 16 different and n.c.i. sites are closer United States and our goal is to open up our infrastructure facilities like Michael fabrication and one of have a kitchen and characterization concepts through extraordinary users so that along with our internal Georgia back users and our partners joins bill of nanoscience and man engineering users extra No users from other academic institutions other industries and garnered Arnie's Asians will have the opportunity to use our facility.

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More information is available at the website scenic conduct Gattex Doc edu so feel free to look at it for more information we also provide currently. While our campus is closed for the global pandemic going all around and you know we also provide our users are free consultations with our technical staff experts and so feel free to use that opportunity with that said you know we have completed 3 technical webinars and today is the 4th one by Dr Hans Chen.

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He's going to talk about 14 of the graph here at our facility is going to give all of you of prophecies and if your payments available for external use that access as well as in turn and use that access as well next week we'll have Mr Richard Schaeffer talk about laser my commissioning at Georgia Tech i.e. n i e n stands for Institute for electronic and nanotechnology that is one of the interdisciplinary research institutes at the Georgia Tech campus so if you have not signed up.

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Register the link provided on top of the slight. To be able to send you the necessary information for a arc of the human With that said it's a pleasure to invite. And interview as my colleague Dr function and he received his bachelor's and master's degree in chemistry from the field on inner city in 2004 and he had assumed his b.s.d. from George attack in chemistry in 2000 and fire and a later was a post-doc.

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At the Institute for electronics and an a technology before joining. As a research scientist in 2008 toll could only Dr Hans and is the process support manager had the Institute for electronic $700.00 technology as the result interests include chemical e. sensed of effect of defect ancestors memes see mass device integration and organic organic electronics and over that interaction it's a pleasure to invite Dr Hunton to talk about 4 of the Gadhafi had our facility in her and all of your processes and acumen not a hunch or.

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Thank you par I think they're ready to join my talk so today I'm going to talk about the list for the father of b. this is very fundamental. Talk about the technique in about the process in detail in art of an interview is our equipment said and what kind of material available are entered the line of my talk I'm going to talk about fundamental flaws our graffiti in including with the concept and in quantum prominence in the repeat and then I'm going to talk about all of those details in the staff in it's there what is the detail and what the problems usually happen on the part of the staff and Latham then they should use our equipment the material said Are you in clear So let's start with the fundamental of the fellas are afraid so policies are free actually in the process you're going to produce a 3 d. the measurement pad on the surface a way for even the lightest and the material or card for that actually just big this for a fee is the most complicated and expensive staff during one of the I think provocations almost one 3rd of the cost was used on the list of of this they have and that including You've been listening to be including the followers of a fee so in our regular processing steps in we spend lots of efforts on of some of these.

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So the concept lists are a few actually there's the 2. Categories So if you already have a pattern you want to transfer the pattern from an existing master 2 or substrate it will kind of contactless our feet so in this contact with summer free there are also a to suck out group of positives are a fee and negativeness our feet so positively summer feet actually you have existing mask which is let me.

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Pointer though you get existing mask with the pattern on it you want to transfer exactly the pattern to your substrate Ok so if after seeing the result of this that you got exactly the same pattern that appeared only your mask with heart of positive side everything but on the other hand if you are creating of Hatter and that is in the UK that of your in this thing are pattern with cardinality of the soccer field so it's in the reversed way and work in making that Ok so this too.

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Is Actually you already have a matter and I have a pattern only to transform to your substrate and now become more and more popular is mask less well as are a feat which is often called it there at writing so you design your pattern with a computer you can use all kind of in software if you use all the cat which is the most easy one to use and then serial equipment you can directly using kind of media you leave the laser and to write a pattern directly to your substrate so in old time maybe 10 years ago you have to use a project printer or stepper to make that happen which is the time consuming expensive and this stays with the the mask the less a liner of here and make the cards and.

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Lower and lower and make the time very shorter so it's becoming more and more popular if they even when you. Ok let's talk about it so we're going to introduce some important promenaders about philosophy the most important is the year falls at the material which is called for this and also light what kind of light what important thing about the light and what that important part of the final mask Ok Well we're going to talk about something about equipment in the car and also talking about environmental condition or a factor for the summer process and we're going to discuss in the lead here when we talk about the process so that generally steps in full authority you have to go through the know you don't have to go through every step in but it's generally speaking you have to go through priming the coding the reverse a little sloppy lime exposure some are this you need to do post-exposure big you need to develop and some time in the heartbreak and you have to check if the call is good enough to let's start with floor that's Ok so for that if you ever have used one of those you know it's sticky material it's if it's full of sensitive you can only open it under the yellow light inside a clear so what that actually containing that liquid so majority of the solvent Ok so you care in the resin which is not for sensitive but it carries the polymer and the liner and you have the sense of hi there which is actually material sensitive to the light and also the additive will change the property of the reverse and provide some special aspect.

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And there are 2 types of 4 of those and calmly you've been clear so part of there are those and then of that so with heart our talk about part of you can part of the reverse you are expose your resist and over the mask here or were is a light can pass ensue with a transparent part of the mask and expose this area so you stop exposure remove the mass and and stripping the realest up you see this part will go away so that part of the we're exposed part of will become solid or can be removed or matter of this if you expose into the lap if they apparently that same thing but after you remove.

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Put in the developer it will dissolve and expose part so what exposed area will remain on the substrate so this will cover narrowing of the so comparing those 2 or there's usually just a speaking part the really the offer better rather Lucian I mean you can get smaller power.

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And now they resist the resolution of the poor rather than part of the Due to the kinds welling in the film and so part of more commonly used in i.c. publication but for special but very popular past that color loved art which is used to departed verifying patterns and negative that have very been very useful so in our queen in narrative it's a very popular and relative taking part in reversing morning expenses and with the relative cheaper.

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This is the full chemistry of the past the fun of that I don't hope everybody can remember that it was a chemical structure of those but remember a part of part of the reverse This is starting material which is called the hero or the and here it is installable Ok so the fall of house or happened when in if the chemical If supposed to a photon and also very important is the water over here so if without water this reaction that it happens so after exposure in the m.b. in the environment need to provide enough water molecules for the reaction to taking place so finally it will turn to this chemical which is our soluble in base so there's a chemistry happen then turn insoluble material into a solid one which are now doing this and little bit different so after exposure that the base material will starting to ready for cross link with another molecule in need a staff which is politics for debate give it limited energy so it can start a craft link with the neighbor molecule the only long chain of the cross lengths that need politics over a pig so without both this that doesn't happen so in this you know sea and water molecule in wafting over here.

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Another type of reverse actually is called Chemical Ali amplifier of the ellipse different from the yearly so one we're typically them for is as you eat series s. you wade through this in the Permian you parts the basin and there are still if falls apart of will become insoluble after process in this reversed there is a chemical look like that Ok so after exposed to our follow up to light it will produce a proton this proton during the post-exposure bake process will cause of Carter craft link of the park the molecule So this is chain reaction like and colors of the fact it will self callout itself and here or the corner of the molecule cross-linked like that so it is.

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Another big type of reverse in just logical understand what the mechanism behind those are for the chemistry so what the function of the 4 of the cell provides to functions transfer patterns so you can create a pattern of substrate for the leaders that if you either do the part of something or the trait or you want to access your supplement your off so those on the 2nd function will be protecting the underlying material during subsequent process like cash like plantation.

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So what's a requirement on the father of the us so one hair resolution that means we can make smaller and smaller patterns so he obviously you the center of this you can get higher resolution but we also wanted to be high actually list and so when we put into the pattern action processor wanted the little with then the heart condition in the plasma so obviously the center of this will give you a poor chemical actually there's that sense in the 2 or contradictory need to find a balance you want that resolution also you want to find it and actually that's them also you one of those 2 stick 3 of substrate well and you're one of those 2 can be prosperity in a different kind of heart I think condition different temperature different committee but that's a requirement of but of this so I'm talking about resolution so I just mentioned the center of the batter but the thickness is not the only condition that's like to guarantee the resolution so if you want to make a new pattern smaller and smaller not only you have to use the center of this you also have to look pay attention to your exposure condition to your kit well up in process so many of the different conditions actually will help for increase the revolution.

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What you want to know like part of there are those have better revolution just due to you had a small inside the parliament cell if you want to achieve high resolution. Resolutions that we used to recommend to you particularly this. Whenever you want to use the pick of resist the most important thing you need to study that they the suit the provided by the manufacturer so when you get the data ship you have to look through important methods still in that the suggested processing condition Ok I just the are.

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From f.d.r. to 20 they were shipped so this suggests that for stellar film and cetera film what kind of paging time exposure doles and pose those are exposure to computer and high angle conformation So this is your starting point in different clear and different equipment all we have to either just or of optimize your process to make the working for your project and other nother important method from they wish it the same curve so you always have to start a study that both of them put if I am trying to you your 227.0 which is this curve I want to see if I want to get a few about 7 Micron and what is what is these.

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I should use a look at this curve and this is 7.5 microns Micron is right here so I look at so I probably use 3500 r.p.m. I can get the 7 microns thickness and to you so this is very useful information it's of study before you started speak only.

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This is the father of this and the developer and the stripper provided by clearance so we provide the real for free so if you come to Georgia Tech ilar clean room you don't have to buy your own if you're just using this this series of or this work for you so to provide form different segments so this is the sickness you you can get at 3000 rpm if you spin fast you can get a thinner film so our partner is there's cover for part of our Leica on a micron up to 50 microns you can diffuse those combination of the those you can get that's that nice and then all of those nearly this too will set if I'm also a user of use and you the rel according developer instead person you can finish your process with material with provider but also this is not only one of those used by users in our community a.v. Siri other in their theory and fury and p.m.a. are very very popular so if you think you want to try some other there's to see whether it's that better and you really can ask you there to do your favor give a small man have a try that's no problem so almost Are you there are friendly to consider the material with you.

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Cyclists talk about a locked case so we're talking about u.v. light. This is the standard light wavelengths that star will appear in the street in for a fuller sucker process so most popular or even if you are equipped with the mark or a lamp so you can get a g. line which is $436.00 nanometer each line for fire and then a meter eyeline $65.00 and then a meter Ok if you equip the with Ixion or laser you can get those higher wavelengths and they are clear we are for they really are for the h. y. for fine and we are in Heinlein's 365 millimeter impress the pole you can get this resolution but is not on our side this is probably can get it ts m. c. or Intel in our clear and with 4 fly you probably can get something close to one micron and with the.

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U.v.. You can get something like a point 6.8 micron resolution with our equipment. So if you really is not nearly equipped on our must line or so if you need that capability need to send a request at. That to put the lamp. Must line. So what are those special aspects truck so if you look at the emissions spectrum of the marker lamps you will understand so this is the are a spectrum of the lab so who is see this 3 sharp pixel here according to those 3 lines that use in the fall is of a piece of this I light a flying g. lines so that a g. on the stand at the other will and there is almost a very very low emissions all that means are not much function has been sent out that way where so you have to select those when learn so you can get enough functional if you really even the laser that's become simpler you only have a one way in their locker learn pick an afro have the steeps you'll be over here I believe and how we doing all of it here but there's efficiency way lower than the laser so it and I have to do long exposure to have enough phone time to know this.

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Only other start and still resist have to be able to absorb the fall of home that's then allowed by the life force so if you study a part of the of the this is the. Absorber incur for normal. Speech you praise part of their lives so you can see this 3 way less restrictive 545 and force 37 so there are enough of his origin so it's not complete or left with a thought from peak but it's pretty close so that means this really wavelengths and resist can have enough absorption in taking the photon but the full chemistry to happen so the green line this is after it is exposed so there's Of lot and become much lower and this is the basement you're almost have very little of loss in those Cleveland.

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But another story is for. Other type of this like s u 8 if you study the absorption curve of a few weight you will find at. Baseline or. July and there absorption is very very low so that's actually as you weight in they receive is mentioned if optimized for highlight only 65 here but if you have a laser or other just light source you can provide that even shorter wavelength you can see absorption will be much much higher and also inside straight on you see the different wavelengths of the parabolic you have penetrating the resist it's going to be different so this is all very important consideration and we will pick up the wavelength and the material for a process we recently have the challenge that our new muscular less liner has equipped with 375 nanometer laser which is over here so we felling that we have to you've very high exposure time to get the expose properly so that absorption occur can partial and when that.

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This is a diagram for the worker lamp the explorer system must our math line or so the marker lamp is over here so it goes through a complicated optical system and folly will serve the lens you can get a unified very parallel to the u.v. light to expose your wafer over here Ok but remember over the time the lamp going to dictate the mechanical system moves so from time to time we need to calibrate the system to make sure the light intensity didn't drop and make sure the uniformity of the light will be uniform across that exposed area.

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So when you do exposure there are a couple of different modes you can select depends on the clipping you're using most of the must Kalina will provide those 2 modes for exposure contact moles and proximity Mole the difference between that if there are any gap between your photo mask and your reverse if you applied Lee has your preserves to your mask that's consider earth contact human in the contact more there are a couple of like soft contact hard contact in a vacuum contact but in present poll there is just should leave no gap in between so the resolution you see the creation will depend on the way when to use and the resists sickness that means you the shorter way was for you thinner of this you can get better at the ocean in a proximity mold there the gap in between so there the reason for people even kept in there so maybe the surface kind of rough and not flat or you have some kind of delicate structure you don't want to.

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Break that so you leave a gap in there so we see the revolution become more complicated so the distance that it went will affect your illusion. So in the projection mode actually there is no contact with the mask and it's a very the best in there so you actually through the light goes through a lens and finally like you cast the pattern on your substrate Ok so that usually involved in more expensive instruments so currently clear and does not have projections liner So our new research center has a one so if you're interested and we can introduce you to our packing Research Center.

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Though this is the market really explain why the best and can call the in the expansion of a pattern so that increased to physical model on Fresno and from whole I don't spent too much time over a year this letter to understand so diffraction can calling the pattern change and also there are the reflection you never work with a perfect substrate so your substrate has kind of a pattern or roughness still light in lending to your substrate surface and will be reflected to.

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Direction so that it also can call the the change of deformation of the pattern during the fall it's obvious that. Surfing other park is full mast so this is the typical for mass So actually this is. A layer of a crawl or. I or our side and on the transparent substrate substructure it yearly is made of solar wind or also like a glass or fins to score or of course it is the best material because almost transparent if you me.

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But if most expensive so I think the whole lime is more popular in the research and yearly we have masks are you how do you look to make math but this is we have the math lifeline or the making for the math way easier so we actually encourage our new There are 2 main math and.

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There was a relationship between mass and resists Ok so there are 2 types of reverse reverse and power in part of the reverse if you want to make a pattern like that's so I have to depend on which resists I use and I can shoot different designs of mass So if I'm using their end of the earth them in this part which remains on the substrate need to be exposed so I need to open a window on the chrome mask and let light into patterns through this area so we can cross-link my full reverse can make that remain if I knew them parted there are that's Ok so I want this part to stay this part cannot be exposed to of light so I have to use cron to block the light on this area and make the rest area transparent so I can hold or I can get the pattern so same parent you can ring with different reversed you can get the Lackland same thing.

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So you really would call the math with majority of the area as transparent part of Clearfield math and math with majority of the area are as. If Dark or opaque were kind of dark few matched. There though when you tried to do alignment there is kind of. Challenges with Clearfield math is much easier because you can see through most of the area with a dark few math you want you to see so in those areas so you have need to think about open the window for green alignments when you design them that's how to make a mass so this makes a mass not much difference in the size of it but you need to for the high resolution you need to get a very good coating over this in the acromion the yearly of biomass clade which already have a chromium and very thin resists layer over there so if you use a lathe or equipment to write the pattern and after development you open the area which is you want to catch the chrome off though you soak your math plates in the chrome actions you can as from off after you remove that for this you can get.

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Your power for the mass So now it's very easy and to make. Your own math for math with our math less line or so we are for the help to making that in well also have an instruction for you how to or you don't or mask less line or to make your own master.

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Other environmental conditions including temperature or a few minute he vibration air pressure is actually controlled by the clearance so from time to time if we see any fluctuation the temperature of the minute it but the notify the universe stop doing this aren't we because we're going to see some sort of different result and we usually think that when the original Pira time particle contamination in Africa with both cleaner and user so we try our best to keep the Queen in particle level in the normal range but if you or you don't thoroughly clean your substrate you also likely will see the particle contamination on your substrate and you will suffer a fall on the poor resolution Ok now talking about the process in detail in your follow the summer of fish.

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The very very 1st if I call is the one you have to make sure you dry your substrate it is very very critical so I know a lot of new you the risk of the stab and later they have some trouble with their this on purpose that so why you need to remove the water so the water all you really stuck on not solid conservatives very tightly because we know there silicon have a nature oxide in there so are we have a penguin pond of our after this they're going out and water like to stick with those then going on so you've got the bacon at heart condition like a $150.00 or 200 degrees c. and they can for a least minimum 10 to 15 minutes or even a half of half an hour just to completely remove water and you can't hear surface or have those hydroxyl group of cash through your substrate and that guarantee the later step will be Small's and trouble free so remember this hydroxyl group is still make the service Hydra full and actually we need service to be hydrophobic which is can get to the resists well so after your hydration the 1st that you will you want to do is to substrate priming So just that actually is to promote that he's an of the father of the 2 or substrate you're a silicon wafer surface the chemical used here is Cod have some Matthew vein Ok if we look at a page and the so that chemical can help promote the he should and usually either the spin long enough to let in some dry or you can do a quickly bake in this remove the here.

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So the h.t.m. and the yes the chemical structure of life that Ok so the are the promotion proof the polls here like and this is the initial state of your substrate after being hydration you have high traffic groups you can now and the oxygen over here in the hydro to group like to attack silicon so making solar can bond like this so so can answer the insulin bomb so and the process going to release and age as ammonia Ok so after the process so you will see the surface well and catch the silicon mass to groove in.

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The service company the hydrophobic though this hydrophobic service can stick to the polymer both for the release really well as a product by product you'll see ammonia there so if you open your is to. Borrow you smell strongly ammonia smell they're usually means your face and the eye has gone bad it's not good for them in the Asian anymore so you need to think about like to buy a fresh bar so for such recording that's a normal way of people doing factory coding you can do decoding you can do sprinkling **** in spray calling Cody is not normal when there are clear because these consume too much material the most likely commonly people to skin falling and juice break holding period so you really stink holding if simple and using the wall in the reverse and majority of values or are you the holy.

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Spirit holding well for the last recording. Capability to the she demands group which is have to restructure on a substrate the which is not super sprinkling Another option is actually lamination so. We don't know off the lamination inside the clearing but our 2nd Research Center has a partial capability available for you there to use in the lemon Asian technique actually you apply dry a filter of this film with a liner and you stuck your with your substrate and the filter of this film and between the roller you can heat you can apply the pressure so after everything if you think well your substrate surface you peel the liner layer r. and you cut and you can get the resists stuck on your softer surface then you can go to the normally exposure and development process you like sprinkled in with this.

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And so during the spin coating you lower your substrate you really have a way for on to chuck with a vacuum in there so the vacuum will hold the substrate and you caseloads that small amount of of this over here and you'll start a spinning process and resists going to Spain and spread and cover the whole process surface so your lease a jazz scheme speed is 3 Stalin to $5000.00 and some equipment offer much higher in speed but we usually don't use that height in speed it's just that is scary when you like the spin at $5000.00 r.p.m. So the process think codings So after casting with this just start a spin slowly and the resists going to starting to spread to cover all the surface of your substrate and after all of this is really this to the test the actual resists will be spinning off the substrate and then you keep continue spending and unify the resist film becomes uniform and solvent going to evaporate forming a uniform fill.

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So you're starting to look at the detail it's been courting process actually refined so if ideal you want to get this kind of coloring but we'll start the spending you see the the flow you are this going to move to the end we'll include the spin speed we're going to push even harder to actually resist to the end so someone resists going to go off from the n.f.c. and the final stage when you reach the equilibrium and you are full of very uniform feel in the center and some as the because of surface tension in the hole part of the resists thinker has the x. Ok so we're working with a very viscous resists like the f.d.r. to 20 and we offer in clear you're not considering like a jump from the staff from 0 r.p.m. and all the way to $5000.00 r.p.m. immediately kind of that in a cost like that the resist that are not going to come in every We're going to cover in small portion of your substrate they want instead of several staff let a spinster lowly 1st not to reduce the spread of well cover every were only or substrate and then you just ramp up to the higher speed to let it's been to the statement that you want.

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So common problem for spend coding lots of time you reported there way for fall for the spring for the quarter most likely your way for backside is not clean there are some particles there and block the vacuum form holding it or some time or vacuum has some problem and you can check that if you're using 2 small chuck or 2 bridge Chuck is also called the or including one problem and some come from coding including if the streaks you see bubbles are part of whole the regular pattern as be so you have to carefully check those people for a start you have to remove all the dust before casting you you have to blow your service with the now just gone to make a long loosely or test dust away and we cast you don't want to get any bubbles in your the forecast and you need to control spin speed and check the results level to make sure the path is going well.

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Brace coding Ok so if you have like a big pattern like a deep trance or something sticking out your substrate and usually spin calling will not get the uniform coding so the spray calling is better for the kind of project and the stink spray coating so you have to dilute the results because that's to most to resist or to viscous for a spray color you have that allude almost 10 times to make it suitable for spray coloring so that solution goes to a novel and spray called it you have to keep a certain distance leaded to space uniformly on your substrate and on the same time actually the novel is in our spray colored and novel is kind of meat and are like this way and from one side to the another side and your substrates like a turn about a 90 degree and the novels are meander back over the floor turn and so it can ensure are the carrier or the patterns will be covered uniformly with a layer over it that but in spray coating so if I'm coding a plan or structure like that and I'll get a pretty uniform coating but if you're working with something has structure like a trench or a have a like a pillar and you can think of or originally on this area have I have straight layers over here but if I have a pattern over here I have almost like Trip old the our service area or so or realist Relayer will be reduced to almost one layer coating them so in a straight color you're not going to get uniform code in every war it depends on we're looking at like a lot of tranced top corner you will see something different so usually if you will see the reverse the process while looking like that cell was different patterns are in different locations you will see different film sickness.

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For that service off they can so the main function for stopping is to drive the solvent out of your is that you don't want your readers to be sticky and when you take to the mask liner to get exposure so and also the staff can help to improve that he can and make the coating more uniform so normally based on temperature you need to follow the procedures so for the datasheet our clear are offered positive resist the typical bacon temperature from 90 to 100 or 11120 and you need the bacon time and you can just sort of 2nd depend on the sickness if you are working with a 10 micron denser seconds that was not enough you have to baking you have to adjust your baking time accordingly so my typical asked under 4 evaluate whether is baked well or not else have my Twitter on top of the to resist layer if I don't see any marks left in there and I'll see eyes is Ok is a steal I can see some marks left and I'll continue baking for 10 or 20 seconds for what the problem with under baking so yeah at least under baking is to Mussulman still less of a sticky end if you take the sticky wafer to do exposure you will find your resists going to the laminate form your substrate and stuck in your photo mask and that ended up you have to do everything all over again but if you are over bake it that could be even more trouble because film each made crack or the temperature too high over the.

[00:39:46]
Glass temperature and then your on your pattern that the 4. And over baked over that it's very hard to remove So I think you need to control the temperature and control the time in the staff as well so you don't want to avoid over fake Your That's. So a lot of the Exploder So if you only have a one layer to explode you don't need to worry about anything select the right of way of lens and ply the mask and set the distance in the mold and set the exposure time you can get things done fairly easy if you want to do alignment then you have the same thing you need to find a feature it's only a way for and you need to find the features in a mask and when you put them together fairly clear you don't want to put them tightly together you want to leave a gap so you can move around and you will see this is going to misalignment at the very beginning so you need to use the function to move your substrate finally make them align well so you can expose the reverse in condition so for the exposure and you remember and even if you have perfect inversion you still can think of any gap in between mask and your river and you have some come diffraction at the corner so ideally we want to get the readers like that and if you do over it's goes down means the lights going to going to shrink the pan you get a smaller pattern then you factor if you were to underexpose if you didn't expose enough you'll see your pattern well can expand a little bit and also about the profile Ok So assuming we're to the perfect exploded those using the properly so think when the light coming through the mask and go to your substrate a lot of photo will be absorbed by the foot of the earth at the top and when the building deeper and deeper well less and less photon will enter to the very bottom part of the reverse and the exposed part like that and the negative this exposed are like that so after you dreamed of developments you will see after removing this exposure part of part of this was left on.

[00:41:55]
The profile will look like that and the negative of this will the profile will look like that so this is very important in later consideration. So post-exposure Baker is required for narrative of this with all the staff in those Palmer is not going to cross-link the normal temperature of about $100.00 or $210.00 degree c. you have to do it right after exposure but at the wildland if you are clear it does not provide those kind of spin.

[00:42:25]
Spray Deval we usually does so how are the way for the exposed waiver into a beaker with a developer so the most important you want to control is the time when we usually like control the temperature with just 2 of the developing and room temperature but the bulb isn't very important if you have 2 overdeveloped or underdeveloped you can see things complete different so this is a couple of them for the like of this is what we expect in the right of op and will give you a future like that if you didn't there Welp enough it probably you have them ready on site and if you devolve too much you have were supposed to be there will be crawling away and he's looking like the back straight like that Ok.

[00:43:07]
Hard bake is not usually done by other process but if your the next that you're going to do actually in this is highly strung least recommended by clean staff because if you still have solved the remaining in a field we put in the hive action system that began calling from trouble because it's all going to it's going to take an hour causing some pop in the holes over here so your you need a little higher temperature than your sop a recommend temperature of a part of there's going to be $12240.00 receive that and always remember the last there is to inspect to check if you don't do careful check of this step and when you move to the next process instead of your final of the problem a real name from the for the start of the staff and to solve the problem that at that time could be much fun challenging.

[00:43:58]
Well you have all the process done finished etching off in this deposition and you want to remove the resist the most the Congo is using the Solomons like at the top as Saddam can remove majority up to solve the rivers but some reverse like a. As you wait for the permanent you won't be able to remove a solvent any of the sama So 1st try at the tone if it doesn't work well you can try to strip her like a recommend for this type or this if the last thing I want you to try is the printer or even plasma but those kind of could call in some kind that meter substrate so you need to sink sharply what kind of mess are you for stripping the off problem all too typical of location after full a soccer field one is edging one the.

[00:44:45]
Deposition for actually you see the foot of here will play as protection later for protecting the substrate you don't want to be to be attacked so think if you're this it use in or is not involved bake and the part not going to hatch the resists over here and finally will can ask yourself straight so it's very important it's like you have to harm bake your this well and also make your profile while because if you have a curvature or a kind of a shape profile over here it will be transferred to that you want if you want good perfectly sharp edging deep trench and you will see the corner works here on the shape of that starting from your for that.

[00:45:26]
Another part of very very popular process in this Queenan is lift off actually used to create a very small man apparent on substrate the Usually people do pattern the for this and they evaporate man on top of it then you then use or just remove the father of this with solvents the demand of sticking fuel for this couple go away there you leave the manuals on where you want to be so this is a perfect process but actually in the real situation if you use the part of the resists you get a profile look like that which I explain in a previous life so then at the time you do evaporation you will see your film actually will become continuous and this time if you remove the reversal here and the metal on top of the drill this will not be removing So that's going to be a problem.

[00:46:22]
So. What will recommend it actually is negative this so now there is this give this kind of profile so that when you do deposition it will not stick on the side wall of your vis the video a perfect resolution if you have to use positive there's another solution that using a material card left after this so little resist is not a full sense there but it can dissolve in dilute based solutions so we're doing developing a little bit over time we're going to attack under the for that some will be evaporation it will even have a start on the sidewalk in front of the Poly or this and that gap can ensure it's not you do not form in the printing of metal film because of Sappho to the left of.

[00:47:07]
Ok so last 10 minutes I'm going to introduce our clearance that Ok so we have a strong team maintaining and clearly equipment engineer a big critic women engineer group and a prophet in team and has 3 clear rooms for you to do all the levels are a feat but have Lotty put provide free resist and will allow many different types of treaty for you to play with we have so this is the Power Man you are a spender so you can do all 5 up to 4 use and things been falling over here and offer very high spin speeds even though I don't recommend it to you that high speed speed and you have to clean it up it is time after you.

[00:47:48]
To spin coding this is our semi auto spin color so it only takes the waiver for an inch or 6 and wait for it automatically you load a waiver and the rest of you can handle it by hand by the harms and you can order a transfer of waiver from the spinner to the hot plate and so only you need to do is casting the Reserves and the loading your recipe and click rum our spray coder and can handle after 10 years substrate and you can spray the curly those where this available in clear for you to use but if you need to be any kind of different with this and please check with that and we can find a solution and we will also have a lot of different type of winds for you to use and musk liner so this is our traditional liner using certificate 5 eyeline u.v. lamp in the it's a pour up to 6 inch waiver and provide one micron alignment accuracy this is our work or so this is Carson's p.s. I'm a 6 and like this multiple of one elf or 2 we went through City Fire and 4 or 5 Ok And based on a request we can put on the level of there is provide amazingly point to Micron alignment accuracy.

[00:49:04]
So this is the cousin of the t.s.a. it can do vets element with this equipment this is our old Mark Earley the writer so we are in the past 1012 years and this is our mass job and rely on this tool to make the math for users as if they fit in we no longer are you that anymore this is our new tool and most popular 2 years of higher birth and I want 15 math less a line and so this is currently the.

[00:49:36]
Most the Wellcome equipment in the clean room and we Georgia Tech is the 1st university clearing that the purchasers to an alley $150.00 in in the United States the university so this must line offered 2 events 375 and 4 or 5 and you can support up to a buy in the squirt substrate and give your point 5.

[00:50:00]
Micron an accuracy. So here is the. Magnum how the math with a line or so in using lasers I was not using the report lab so the single way when coming over here go to the special lab modulator actually if they're actually processing your file from your software and then can cast that sort of the micro.

[00:50:23]
Rate and directly by the pattern on your substrate and the substrate the plate can move so you can cover that whole area very quickly so you can see these structural conduction one micro and they offer 2 we've learned that but this if you 75 lenses kind of a very behave very different from certificate farm then a meter we're still struggling with that how solve that problem and you can see the good Lymon accuracy and actually you can do real time of focus that means if you're substrate is not even so during the running time you can automatically adjust the focus to make sure whenever the height you can write properly in this case for that you can see the 2 micro features though is that it's very difficult to write a pillar or polar structure like that so you can see it's writing pretty well and this Ok is showing the line accuracy which is the top layer of line pretty well with the previously you're on the substrate and the bird Paul structure a very straight structure is kind of very difficult for traditional must.

[00:51:32]
Be a must lining process of their equipment handle that pretty we'll. The last equipment I want to introduce is really little actually is it or is not traditional no way of informing us of a fever in our one hour music ability in with us none of us are a fee actually provide structure in space Ok so you're in the liquid reverse which is for the green area over here so with a focus beam only on the focal point you will craft link the reverse so actually you can riding the structure in this base Ok so the features of the tool have a $201.00 I mean or lateral Aleutian a foreigner anatomy or vertical revolution it is doing 2 full time polymerization tactic to make that happen so I can explain and that's life and you can ride in 100 my 100 millimeter 400 large area like right on the 4th wave or so it is very fancy technical So let me explain about up to form Palmer they shouldn't so you're wondering so light sanding and this area why this area is not being exposed so if you're using a single photon in which light you see a photon the Palm are going to be polarized and you won't be able to write the facial structure but with 2 photons So actually there are 2 being with the 2 different energy level if it's i.r. laser and folk of b. in meat over here so this specific point and polymer receive one photon and jump to and state intermediate state over here in the 2 immediately get another photon from the 2nd laser beam to jump to 2 to define a levels of releasing the information that means only 2 beings meet in the space and that specific spot can be explained that's why it can offer you the capability of writing the space so here is some showcase for dance and this is Mall as the bust in of Georgia Tech in look in the background of the penny it is the height of a penny so we are creating teeny tiny parts and.

[00:53:38]
This is a picture I got a fond the vendor website itself you can see on we'll see concrete very refence the structure will be known as scrap. Now. This is the end of my talk and. Thank you for listening to my talk and questions. Thank you thank you for your wonderful person to say it's really informative and we appreciate it thank you and he questions.

[00:54:13]
Well if there are no questions thank you all for ending once again I would like to thank our speaker for today Dr Hunt Jim for a very informative. Presentation on 4th of the graph of capabilities at the Georgia Tech I can't.