Drawing Microscopic Patterns with Electrons

Today we're looking at Electron Beam Lithography using a scanning electron microscope
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==== More E-Beam Litho! ====
peterbjornx has recently been converting his SEM to run litho patterns. Particularly interesting since it's very DIY (vs the python api for my machine):
- / 1489776638841737217
- / 1487015399388598277
And of course the infamous Sam Zeloof did a video on the topic years ago 🙂
- • Making Tiny Things wit...
==== Never Gonna Give You Up :) ====
Never Gonna Give You Up remix by Kingdom Power Music ( • Rick ASTLEY - Never Go... )
Kingdom power music
Instagram: / kingdompmusic
==== Timeline ====
0:00 Intro
2:02 Electron Beam Lithography
4:56 Substrate Choice
6:02 PMMA Resist
7:47 How do e-beam resists work?
9:35 Development
10:47 Results!
14:18 Dose Dependence
15:06 Resist Thickness
15:19 Substrate
15:22 Accelerating Voltage
16:03 Proximity Effect
17:06 Emission Current
17:35 SEM vs EBL
19:50 Fast Beam Blanker
21:13 PMMA dosing - Positive vs Negative resist
22:21 Next Steps
22:49 Curiosity Rover Wheel!

[@AppliedScience]

Really cool stuff! I'm looking forward to the rover wheel design course.

[@BreakingTaps]

Thanks Ben!

[@st3althyone]

NEEEEEERRRRRDDDDSSS!🤣😆🤣

[@seditt5146]

@@BreakingTaps Have you two ever collabed? I could only imagine what the two of yall could come up with.

[@st3althyone]

@@seditt5146 That would be amazing.

[@felixman9691]

Meeeee toooo!!

[@HM-Projects]

Mixed feelings, I don't see many taps breaking in your videos anymore. I'm very glad that you're making these videos though 😘

[@BreakingTaps]

Fear not! I've been doing a lot of machining work lately in the new shop and hope to be showcasing it in future projects (including, alas, many broken taps). Have some interesting stuff that will feature various machining and engineering stuff :)

[@jimurrata6785]

​@@BreakingTaps I hope you've made yourself an EDM to eat those broken taps out of the hole. 👍

[@keith_cancel]

This is still technically subtractive manufacturing. Just so tiny that you can't use a tool to directly cut the features so one use acids instead for example. Although it can also become additive if instead of using an acid you deposit something lol.

[@seditt5146]

@@keith_cancel Currently its just photoresist correct? I believe he could go any direction from here. Vapor deposition would yield additions. Acid etching could create subtraction. Hell pretty sure he could even use this to dope the wafer because I am almost sure I remember seeing it done somewhere in which they placed solutions with the dopent on top and the electron knocks some atoms into the silicon. It gets put in the photoresist. I'm over here excited after I was able to recently create my own specific gravity balance with scales of roughly 20 milligram and 4mg tolerance thinking i have good precision and this dudes over here capable of making his own nm microchips and shit.

[@UnitSe7en]

No spigots, nozzles or stopcocks, either!

[@izzieb]

I used to watch pictures painted with electrons all the time. Now I'm watching this video, which is painted with electrons in a different way.

[@nixietubes]

Or both ways if you're cool 😎

[@ProjectileGrommet]

Underrated comment

[@AsymptoteInverse]

Come to think of it, electron beams are probably how a lot of people saw Rick Astley for the first time. And now he's back!

[@MrApple-yw9vp]

Ive been Rickrolled by an SEM image, nothing could prepare me for that...

[@Mireaze]

I know this video took a while, but I'm glad you never give up, you never let us down

[@1224chrisng]

he truly never ran around or deserted us

[@st3althyone]

I see what you did there. 🤨🤨

[@tomjohnson5713]

He never even said goodbye... how rude

[@nathanwilson58]

Amazing how far your home cleanroom has come! Some of the smallest features were probably washed away during development due to their high aspect ratio. I suggest a post-exposure bake unless you want to invest in a bottle of adhesion promoter.

[@BreakingTaps]

Noted! Will look into some adhesion promotor!

[@st3althyone]

Friends help friends get baked. 😆😆

[@EvanZalys]

PMMA doesn’t really need standard adhesion promoter. An ion mill or o2 plasma should do the trick.

[@CharlesVanNoland]

My late father named his precision machine shop "Sub-Micron Precision". He wasn't doing anything that precise. We could hold +/-0.001" but his whole theory was that people would just hear the name and believe it. Miss you dad, wish you could see how far I've come on my own with CNC machines and life as a husband and father. RIP

[@joejane9977]

take all the time you need for content. the mental health of our creators is worth it

[@cdburner5911]

Fun fact about the rover wheels, the engineers at JPL were developing (though it didn't fly with curiosity) a modified wheel with a Raman spectroscopy sensor in it, where it would take continuous samples as the rover drove. Really clever. It was behind a sapphire (I believe) window.

[@graealex]

Raman (after the guy), not ramen, the noodles

[@cdburner5911]

@@graealex Doh! My bad. Thanks for correcting me.

[@HuygensOptics]

Glad you're back Zach! And on top of that with a lithography video, my favorite subject. Being Rick-rolled in that intro was great! 😃.

[@BreakingTaps]

Thanks! Was a nice little YT holiday, feeling much more refreshed now :) I have several of your videos queued up for watching since I've been away, and I hear rumor your most recent one has a fun surprise 😄

[@HuygensOptics]

@@BreakingTaps That is correct, you can exercise your dance moves while at the same time get informed about some important optical concepts and terminology😉. KZbins AI classified the video as "Comedy" which was not very good for views, because of course it wasn't. Ah well, who cares. Most important thing is to keep doing the things you like most.

[@BreakingTaps]

Oof, always frustrating when the Algo decides a particular video should or shoudn't be shown. I have some videos which I spent months on do terribly, and others that I basically threw together in an afternoon and expected to do awfully become some of my most viewed. Sigh 🙃

[@RobertElderSoftware]

This video has convinced me that the first practical homebrew DIY CPUs will be created using electron beam lithography instead of photo-lithography. The advantage of having a higher beam precision and not having to deal with unwanted exposures from lighting in the room would be a huge advantage. The disadvantage of much longer production times won't really be an issue when you are your own customer.

[@graealex]

Not really, hard vacuum and electron beam makes it pretty complicated. Still thinking about Huygens home-made DLP stepper. And DIY stuff doesn't need to be small either, you're not going to get a good enough and consistent process control for multiple masking, etching and doping steps at nm scale at home. A 4004 is 10um structure, yet until now, no DIY version has been made. But should be more than doable with rather simple photo lithography.

[@RobertElderSoftware]

@@graealex That's a good point, I forgot about the need for a good vacuum. I wonder if there is any kind of novel and 'innovative' way that you could just not use a hard vacuum, or maybe just a lesser one? I suppose the problem with normal atmospheric pressure is probably that it causes electron scattering? I wonder if there would be some clever way to avoid/minimize the electron scattering with different gasses/materials etc.?

[@keith_cancel]

@@RobertElderSoftware Applied Science showed how to make a scanning electron micro-scope years ago. A lot of overlap so that could be used as a starting point instead if one does not want shell out tons of money for something pre-built.

[@graealex]

@@keith_cancel But you have to agree that the DIY microscope was shite, compared to the commercial one he got as a replacement, although still quite an old model. Making this stuff "at home" is just not feasible.

[@hamjudo]

Check out Sam Zeloof's work. He made his own UV lithography setup and made the first DIY integrated circuit in his parents' garage. It was an OpAmp, but his long term goal is to make a CPU. He has graduated from highschool and is now off at college. I wouldn't be surprised if he shifts his focus to something even more amazing than making a DIY CPU.

[@beartastic-ftw]

Oh, definitively take care of you first, youtube second - kudos for that and being open about it!

[@smellsofbikes]

Item 1 is how much I love the almost spy scene at the beginning matched with the googly eyes on all the equipment. Item 2 is all the rest of it is just amazing.

[@BreakingTaps]

Googly eyes truly make the world a better place 😊

[@nonsquid]

With this resolution, you should be able to print a conductive tuned antenna array for a specific light wave frequency. For example, a blue laser with a known wavelength of 490nm would have a dipole antenna length of 490nm that would exactly absorb the coherent light energy and convert it to electrical power. Could you print a tuned array of 490nm dipoles then hit it with a blue laser to see what kind of conversion factor you would get? If you could print a whole array of different dipole antenna with lengths in the visible range, you could make efficient light collectors for detectors or possible power generation.

[@randomname4726]

I would love to see this in a video.

[@BreakingTaps]

Well that sounds interesting! Will do some reading, this is way outside my knowledge at the moment but it sounds like it could be a really fun project!

[@Eltro101]

@@BreakingTaps You can get SPR plates pre-coated with gold that should enhance the coupling with the light even more

[@mikejones-vd3fg]

@@BreakingTaps The commenter is suggesting that with this technology, it would be possible to create a pattern of tiny metal antennas on a surface that are specifically designed to absorb a particular wavelength of light. For example, they mention a blue laser with a wavelength of 490 nanometers. The antennas would be designed to have a length of 490 nanometers, which would make them efficient at absorbing this particular wavelength of light. By creating an array of these antennas, it may be possible to create an efficient light collector or power generator. When the antennas absorb light, they generate an electrical current. By creating an array of different antenna lengths, it may be possible to efficiently collect a wide range of different wavelengths of light, which could be useful for applications like solar energy or high-resolution imaging. (Chatgtp maknig sense of the comment)

[@mikejones-vd3fg]

to be fair chatgtp also just repeated what the original commenter said, without understainding that we dont understand lot of the industry specific terminology and if youre goal is to help people understand, its not helpful talking this way, so i just respsonded with "i dont understand" and it gave a more clearer explanation for someone whos not deep into this stuff, a simple array of small attenas for power genreation, sort of like maybe how solid state fans with their many vibrating membranes that give them some crazy blowing air efficiencey compared to spinning fans. Same could happen with solar energy which could be huge. Solar in the winter is pretty inefficient unless you have crazy amount of panel, even just a doubling of efficiecy could change that and the more energy independance we have, the less we all fight for oil. And the universe is full of it, yet we're hunkering down to stay on this planet forever which is impossible and shows any lack of foresite about the universe and our time to eventually get off this planet for real will come one day, i hope we're motivated to leave before then. But i have a feeling exploding bombs as propellants isnt going to cut it for energy. And ultimately, the universe made energy, maybe it can happen again? why do we have to suck energy from stars even.. those wont last forever either, where did they get their energy from? maybe we can get some there too. Anyhow I agree with original commentor, it would be cool to see what kind of power efficiecey an array of tiney metal attenas could produce in the same wafer space compared to a solar cell or something. And as good as chatgtp is with its knowlege, it wouldnt have come up with an idea like that, so we still have a purpose hehe.

[@ARVash]

100nm, that's GameCube territory. It would be cool if you used this to print out an 8086 or an arm chip, probably more attainable as you'd have quite a bit of room for mistakes.

[@anon_y_mousse]

Now that is something I'd like to see. Printing old chips to repair old devices would be awesome. Or even just build a whole new one from scratch.

[@st3althyone]

That would be a great project to work on. I’m sure it would take a shit ton of time and effort, not to mention the engineering required to accomplish the task. Not insurmountable, but challenging.

[@andreanardi6301]

Many of the retro chips have a corresponding VHDL implementation from the MiSTer project. I would be could if we could transform those into a silicon design and replace some chips.

[@SianaGearz]

I think you have to consider the small scanning aperture and difficulty neatly stitching together multiple scans. I suggest that very simple chips could be a better first target, sneaking up on 4000 gates which is 6502 complexity. It is perhaps exciting that you can image something really small and fine detail, but you still have difficulty etching and whole chemistry and with lack of cleanroom environment. There are a lot of low complexity custom chips lacking in availability which are dying in classic computers. Also call Sam Zeloof.

[@anon_y_mousse]

@@SianaGearz Not only would that be easier, but it could potentially be very lucrative as well, which would help fund building more infrastructure and allowing for a gradual increase in complexity. I would love to see that happen.

[@thereasoniswhatever5068]

My first run-in with this technology was when I was 13. It took me a while to understand how a microscope could be used to produce images instead of taking them. What helped me open my mind to the idea was a simple camera. If you have a camera it takes a picture, but if you were to shine an image out of the senzor you would literally get a projector. I know it is not the most acourate example, but it helped me understand how a taking device could be used to produce and image.

[@beartastic-ftw]

Congratulations; first time I've enjoyed being rickrolled and not even seen it coming..

[@clint.]

You're videos are never too long! Yes, I may not watch them in one sitting , but I have ALWAYS finished them. Thank you so so so much for sharing explorations of these phenomena with us. I am entranced and truly enlightened while watching your videos. Don't ever stop sharing your incredible talents with the world! ...of course, do it on your own terms, at a healthy and sustainable pace. No one cares if you only post once in a while. Your videos display weeks and months and sometimes years of effort. I am rooting for you man!

[@adrianpip2000]

Glad you're taking care of yourself, and smart enough to have a break when needed! Also, I rly love your videos. I'm just a humble chemist to-be, but I thoroughly enjoy videos like these (you, Applied Science, Huygens Optics, BPS Space, etc.). Rly hope to be able to have my own small workshop at some point in the future

[@Holagrimola]

you're so good at explaining these kinds of things, it's so easy to follow, and actually understand, really a rarity on youtube!

[@ryannickles3218]

This is one of those videos where I wish I could like it twice.

[@joshgilligan5466]

Absolutely loving your content, you've been a large motivator for side projects of my own (currently attempting to build a light sheet microscope)

[@st3althyone]

OMFG! We’ve been Rick Rolled via Scanning Electron Microscope. This has to be the most Giga Chad Rick Roll ever. Congratulations!

[@RiffZifnab]

Finally a use for all those CD case covers! (: Glad to hear you were able to take some time off when you need it. Those wheels already look amazing, also it's great they are made from the same (general) material. It's bonkers to think how much force was required to abrade away that much aluminum. (:

[@BreakingTaps]

Thanks! And yeah, it also blows my mind how the real wheels were made. Much larger, milled from a single block of aluminum, and the "skin" of the wheel is just 0.75mm thick! 🤯

[@SeanBZA]

@@BreakingTaps I know a machinist who made new bushings for a machine. Bronze, and he started with a 60kg block of continuously cast bronze alloy, and the final bushing was sub 1kg. Plus nearly 60kg of scrap as shavings, he ended up with a final wall at 2mm in places, from the 400mm diameter original block. Needed to put in both eccentric holes for adjusting, plus machine in the gear teeth on a ridge to allow it to be adjusted, plus all the oil grooves and passages to allow both sides to receive lubrication. No drawings of the original, just good measurements of the existing shaft and the hole, plus the worn part to take measurement from. That was about a month to make the two, each coming as separate 60kg cast blocks.

[@st3althyone]

That is so amazing!

[@adriandewambrechies2204]

I recently started my PhD and got my hands on an SEM, I can relate so much with this video and it’s super helpful thank you so much!!

[@CEOofLibertyMutualInsurance]

As someone who works in a materials characterization lab and is about to start a project with EBL, this video has been great for getting an idea of what I'm up against. TYSM!

[@WaffleStaffel]

Funny, I just today happened across Richard Feynman's *1959* lecture _"Nanotechnology, There’s Plenty of Room at the Bottom"_

[@bok..]

that rover wheel is super fascinating! I would totally buy one because as someone with Autism its always nice to have something tactile for sensory stimulation. Also i like space stuff.

[@23chaos23]

DUDE! best video yet, freaking loved it!

[@RichardGreco]

I did research in using MeV proton beams for lithography. Proton beam writing has advantages, high aspect ration (depth vs beam size, ~1 um^2 vs 60-100um depth). Accidentally created buried features, where the surface was under exposed (electronic stopping small) and the buried region was fully exposed (nuclear stopping high near end of range). Ice cold 70% IPA is a amazing improvement. We used IPA/MIBK as a developer and had a hard time finding the perfect balance of dosing and developer, especially for deep feature.

[@fluffy_tail4365]

this channel is just incredible man

[@sambojinbojin-sam6550]

An idea for the production problems at 13:38 might be to throw a small ultrasonic piezo transducer in while you're giving it the acetone bath. Essentially vigorously shaking the fluid, instead of the wafer itself, to give a more thorough monomer removal process. Might speed it up a bit though. Or delaminate it a little more. I have no idea what power or frequency you'd be aiming for (it would be container and liquid volume dependent anyway I'd guess).

[@mystamo]

Woah Zach this channel blew up! Do all your projects have to be soooooo incredible?

[@SeanJonesYT]

Hey man! I've been watching your videos for a few years now and these videos have become an instant click when I see a new one launch. I'm curious what your background is and how you got into this space; what did you study in school and how did you start? You and Ben from AppliedScience are my biggest inspirations for my dream of having an awesome home lab I can run experiments in, but I don't have a background in engineering and I just graduated university with a computer science degree so I'm not sure where to start. Looking forward to the next one!

[@BreakingTaps]

Thanks! :) So my career has been sorta all over. Went to school for CS, but switched to biology and graduated with a degree in molecular/cellular bio. Worked a few years in labs culturing cortical neurons and running cell assays, aiming to apply to grad schools for a PhD. But decided academic bio was a poor career choice and quit to do some programming freelancing (just simple website stuff at the time). Eventually joined a search/analytics software company (Elastic) and worked there for like 7 years, quit a year or two ago and am now somewhere in between a machine shop and a youtube channel, depending on the day 😅 All the material science/optics/microfab stuff is just interest from an amateur, no real training in it. Just find the stuff really fascinating and that leads to late nights reading papers and dreaming about how it could be done in a more modest, non-lab environment :)

[@anon_y_mousse]

I don't care what anyone says, I love that song and I've loved every Rick Roll I've been served. Although, this is certainly the highest class version I've ever seen and probably will ever see.

[@jperk1022]

Loving the nano science content! I wish I had access to a budget EBL in my lab for small iterations or tests. However I do have direct access to a wide variety of unique optical coatings (both metal and phase change materials).

[@coyotedomino]

somehow simple and accessible, yet also in-depth and complex. fantastic vid! have you seen the thought emporium’s project with neurons? they had trouble getting traces small enough on the slide for neuron growth, but this with vapor deposition would be perfect for that

[@BreakingTaps]

Thanks! And oh yeah, I remember that video! Is he still working on that project (it was a year or two ago iirc)? I'll give him a ping and see if they need any help 👍

[@jakobhalskov]

So educational, well explained and pleasant to watch! You are an awesome inspiration in many ways, and I am happy that you do your best to take care of your self (and share openly about it). Best wishes from a fellow KZbinr from Denmark. / J

[@MBG_Broker]

Man it has been a while. You always manage to just hit that sweet spot between being general nerdy and scientific. A suggestion to what you can use your new found skill for is "microfluidics". Would be cool to see a cell separator or some wacky liquid logic. Hope you the best on future projects.

[@BreakingTaps]

Thanks! ♥ Will take a closer look at microfluidics! I'm only familiar with the field from a really high level, but looks like there are a lot of cool potential projects now that I have a reliable litho technique

[@uggima1]

Great to see more of the work you're doing, always a nice supprise to see a new vid. Don't expect you'll see this but either way thanks for being awesome!

[@BreakingTaps]

Thanks! I try to read through all the comments, although replying to all of them is usually too challenging :)

[@peterbosc]

Thanks for the mention in the description! Hopefully I'll be able to finish my video on this soon :)

[@Veptis]

Some of the cutest things I have encountered is tiny wafer carriers. Like they normally make them for 300mm wafers or 50mm wafers for R&D. But at home I have some for 22mm wafers, or a 10x10 piece sliced from it. And yes, they open up the wrong way.

[@randomname4726]

Really great video, as always! You, 2strokestuffing (Performance 2 strokes are a suprisingly complex science) and Cranktown City are my favorite channels lately.

[@abitofyourbrain]

My gosh that is really beautiful to watch. Also, I love the googly eyes. I thought I was the only one who stuck those on the lab equipt like that Thank you This is very helpful ❤

[@airsoftwwbde]

i love your work, keep it going!

[@jasonbrotherton]

I used to do a lot of EBL on a similarly jank system. It sounds like you would benefit from having a 'dump' area that the beam draws at the end of your process. Basically add a box that takes 30 sec to draw at the end of your pattern of interest. Then you can stop the process within that 30sec window and it won't effect the pattern you care about.

[@DonMr]

This is the video. Magical my friend. Thank you.

[@whoho1]

Your videos are absolutely lovely, i object to this video being to long though. I would have loved more details :) Lookin forward to many more of your uploads. I would love to hear about the design history of those rover weels :)

[@4n2earth22]

You know those great big fans they use in, say, COSTCO or other large warehouses? Yeah, I am one of those. Keep on keeping on! 🌞

[@Spectre4490]

When at 10,000 year new civilization find Rick Roll on piece of silicon, what will they think of?

[@ppage27]

Amazing and very clear video! Learned so much!!

[@subliminalvibes]

Holography. I need this for holography! Sub micron lithography would surely work well for reliable reproduction of interference patterns...

[@chopper3lw]

That's a hella lot of work for a Rickroll! Nice. LOL

[@BreakingTaps]

Only the best for my viewers! 🥰

[@Voulltapher]

What a cool Video! Thank you for making them educational and entertaining without losing too many technical details. And please don't feel obliged to post Videos, stay save :)

[@yotacoil]

Goodness, I have worked in the field, and every day, wondered: this electron microscope can clearly hit this sample exactly the same way an e-beam could, why can't I just write using the instrument that clearly already works? Glorious to see people are doing it!

[@mastershooter64]

another breaking taps video let's gooo!!!

[@user-gi3my2qk9b]

Absolutely loved the video!

[@rossknowles5608]

amazing as always

[@RaleighC]

This so cool and your results are absolutely incredible. Shameless plug for my startup, Ephemeraltronics. I'm working on a low cost electron microscope for high schools, universities, and small businesses that hopefully will also enable this exact process.

[@vegandiver]

Super cool! I love EBL. Neat that you can do this for fun at home!

[@WoodsyDotOrg]

I wonder if it would be possible to create PNP/NPN junctions with the over-electron-exposure in the resist. Making the resist itself semi-conductive would be another hurdle though.

[@jinwookim1296]

I'm working on photolitho at Purdue, glad to see others working on it.

[@Jimunu]

I love the old cd/dvd holder lid splatter protector.

[@Kek5kopF]

this man is incredible

[@forbiddenera]

I love how I have you set with the bell on but am seeing this 3 days later. Screw you youtube. I think this is literally like one of maybe two channels I have with the bell on too as the videos are always awesome.

[@BreakingTaps]

♥️

[@kayakMike1000]

That wafer is dope, man.

[@THEOGGUNSHOW]

I'm loving the anthropomorphic lab equipment

[@BreakingTaps]

Everything is better with googly eyes!

[@leflavius_nl5370]

Oh boy dis gon b gud time to take a break in my process engineering excel work.

[@leonbogman5074]

Loved this video!

[@Joao-pm8je]

1:21 most satisfying pour

[@jbrownson]

Love your videos, thanks

[@avelkm]

Great video, as always! Following from the first days) Please take care of yourself, mental health is extremely important! Thanks for education)

[@joels310]

Dude! This is freaky awesome! I kinda want to spend all my nonexistent money on one of these now!

[@jimsvideos7201]

This is at once banal and utterly astonishing.

[@DEtchells]

Another super-cool video! For slightly more automated proximity-effect exposure control, what if you took the image into Photoshop, copied it to a mask layer, then run a Gaussian blur (or some other blur operator) on the mask layer to get something you could use to vary the darkness of the original? You could adjust the amount of the effect with the transparency of the mask layer, and the range of the proximity compensation by varying the radius of the blur operator.

[@BreakingTaps]

Ah that's clever, I like that! Should give a pretty good rough approximation I think, since the effect is mostly a gaussian process under the surface (and some similar but longer range fogging from backscatter on the top). Will give it a shot, thanks for the idea!

[@DEtchells]

@@BreakingTaps Great, I’m happy it was helpful! Ah, I’d only been thinking about the backscatter, but thinking of your results again, I realize that the worst problems were on very fine-pitch detail, so that would have been more the subsurface effect. Ideally then, you probably want two mask layers, to model the two processes separately. The next question is calibration. For the backscatter, perhaps you could create a test structure with a high-exposure spot in the center, and then some sort of radial pattern around it of elements having different exposure levels. Perhaps something like a row of lines spaced broadly enough to avoid the worst subsurface effects. Then make a radial pattern of such rows around the center spot with different exposure levels. Run that and see how the ideal exposure varies as a function of distance from the bright center element, and you should be able to get some approximation of both magnitude and extent of the backscatter effect. Make and test a mask for that. If it’s close, you can then use it as a baseline when figuring out the subsurface effect. Of course, I’ve probably just described a few weeks of experimentation for you, easy from my end 😆 I love this sort of tricky physical system. I’m good at things that involve physical processes and mental models of them - but am complete crap at anything involving higher math. It’s the reason I bailed out of a PhD program in Applied Physics: I barely squeaked through the written exam and knew there was no way I could handle 3 hours of profs throwing problems at me on a whiteboard 😮 I love this kind of stuff though 👍 I forget, do you have a Discord? If you do, I’ll follow it. (PS: It would be way over the top, but I think the ImageMagick package lets you apply arbitrary convolution kernels :-)

[@pasha92]

Cool video, nice result :) Our lab staff would kill me if the spinner chuck I use would be so dirty with photo resist.

[@BreakingTaps]

Haha yeah, I can imagine :) I used to have foil covering it for easy cleaning, but was a PITA with this spinner design. Will just replace the cover at some point instead

[@xanokothe]

Yes Finally!

[@cyber2526]

isn't this how silicon wafer are made? =D

[@cyber2526]

i just got here i haven't watched the entire video yet don't judge XD

[@patrick247two]

Best intro ever.

[@DanielSMatthews]

"Electron beam driven dopant diffusion in semiconductors" is a thing, so what is to stop you writing a custom one-off circuit directly into your silicon wafer? Digital holograms with the interference pattern rendered from 3D geometry files would be fun too.

[@BreakingTaps]

Interesting! Didn't realize that was a thing, will do some reading on the subject! Even without that it should be possible to do small circuits (Sam Zeloof is doing that via more traditional techniques). But being able to dope in a controlled manner with an ebeam is a really interesting possibility. Probably faster/easier/more accurate than traditional thermal diffusion and masking. Thanks for the tip!

[@DanielSMatthews]

@@BreakingTaps If you escape from the _"I need a process that will make millions of these things fast and at a low cost"_ mindset you should be able to do a lot in the bespoke integrated electronics area. It also makes the mind boggle as to what is going on in some classified lab somewhere, and has been for decades.

[@a.bridges]

Very nice patern 😀

[@thomas-nk7kx]

didn't know that you used the Phenom XL, nice surprise! we assemble those at work :)

[@chrisreichelt7202]

As always, great video! Please make a batch of the rover wheels!

[@user255]

Very interesting video. Again. I wonder if this technology is used for military purpose ICs. All I have seen is quite the opposite, old military electronics use even older parts. But I just feel like this could be handy in some psy tech.

[@seeigecannon]

If you are worried about the acrylic not being fully dissolved (so long as it actually is acrylic instead of a contaminate) you can try putting the solution in a ultrasonic cleaner for a few minutes. At work we do this with all of our samples while we are preping them for the HPLC.

[@BreakingTaps]

Will give it a shot! Might also be impurities/contamination in the acrylic itself now that I think about it. I assume those resin pellets aren't processed in super clean conditions...

[@seeigecannon]

@@BreakingTaps something else you could do is run the solution through a syringe filter. At work we have those down to a filter size of 0.2um.

[@1kreature]

I've never been so satisfied of being Rick-rolled before :) And I still get to enjoy the entire explanation of how it was done.

[@CyrusTabery]

Perhaps small nit picks on a great video : 1. Ebeam resolution is not diffraction limited. It is limited by aberration in the lens or from resist 2. Modern Ebeam resists are very similar chemistry to euv and duv resists. They use chemical amplification from an acid catalyst to knock off a protecting group which causes the polymer to be base (or solvent in negative tone develop) soluble. 3. Production Ebeam litho to create reticles is all 50kV landing energy. There is a sensitivity trade off that makes this the best landing energy.

[@BreakingTaps]

Cheers for the corrections!

[@violincrafter]

Not sure if you will ever see this, but I’m a uni student who had to EBL extensively for my project. I noticed a few things different between our processes! First, your use of cold IPA is good, but you’re only putting a couple mL on your wafer. The heat capacity of everything from the wafer to the syringe is going to influence process temp! And temperature is a very important process variable: the kinetics of solvation is proportional to exp(-E/kT)! For me, I take a beaker of 0C 3:1 IPA:H2O and dunk my chip into it, and never let it go. And I VIGOROUSLY stir it around to ensure the exposed areas are always seeing fresh solvent at a consistent temperature. That might solve your particle issue as well. I try to keep my process as close to 30 s develop time as possible. At the last step, dunking the exposure in water will certainly arrest development, but if your PMMA features should be taller than they are wide, you risk the surface tension of the water collapsing your pattern during drying. Along these lines, I always determine the resist clearing “dose”, in uC/cm2, experimentally, and it of course depends on the average exposure of the proximate area. I didn’t see you mention this number, but I always use it as a very important parameter. For Si, the proximate area has about 7 um radius for my 30 kV system (converted SEM). The range is actually shorter for lower kV, but the proximity effect-induced exposure is much larger over that smaller range. Good luck on your future EBL! If you are still doing that.

[@pappi8338]

That was a fantastic read! I work with Thermal Nanolithography, but I have used an Auger Nanoprobe. How long have you been using your recipe for?

[@violincrafter]

I've been using this way since last year. Sometimes I change it up when I don't need that good of a resolution (not much difference in the end really). I increase the develop time and use room temperature.@@pappi8338

[@Scrogan]

I’d like to see what other equipment you’d need to then make diodes or JFETs, now that you have e-beam resists.

[@jeffreypomeroy6173]

I abandoned using ebeam due to secondary electrons causing excessive resist exposure but i was using hline resist. The process was ridiculously slow at the accelerating voltages i was using. But i made schottky diodes and mesfets with copper sulfide (Cu2S) and aluminum (Mg worked better but reacted with my developer unless capped with Al).

[@gorak9000]

Does he have a working implant process? You definitely need that to start actually building devices.

[@ShopperPlug]

4:00 - In the future I bet E-Beam will be the next tech used for advanced highly integrated and smaller process of semiconductors in which photons just can't suffice and hit it's max limit. I read some patents for making e-beam faster for higher throughput suitable for semiconductor industry, it uses multiple e-beams in one machine, but it was ditched in favor for photo lithography being so standardized and being more commonly known in the industry.

[@nixhound]

Every two minutes I kept pausing the video to show my partner, against her will, because the video was a constant barrage of fascinating images. The thing I kept bring up was that you are working on a smaller scale than bacteria for example. The AFM images were the best of all with their "roughness" was really interesting.

[@gorak9000]

I don't think there are too many people that fully appreciate just what's going on in these videos. It's like the beginning stages of what billion dollar companies with hundreds of thousands of employees do with billions of dollars of equipment, but it's one guy in his shop at home! One the one hand, I'm like "psssh, yeah, I see better stuff every day, but this isn't a multi-billion dollar company - it's just him, in his shop [mind blown]"!

[@AhmedFromKSA]

If you do sell the mars rover wheel's as merch I would definitely buy one!

[@goguen55]

Dito

[@cncrouterinfo]

In addition to that at 20:06 - the beam blanker is not a electro magnet. it is 2 plates which charged positive,negative depending on you want it to blank or not. Actually a super simple piece of electronics to make. Would be easy enough to retrofit.

[@BreakingTaps]

Ah, just electrostatics then. Makes sense, cheers for the note!

[@davemorphling7432]

Thanks for this video! I'm very interested in experimenting with lithography in my "lab" but I don't trust myself enough to deal with chemicals safely. By any chance, are the chemicals involved in e-beam lithography safer to handle?

[@unvergebeneid]

You know you're in the range of nanoscale manufacturing when "a couple microns" qualifies as "really thick".

[@jonathanseagraves8140]

Are you trolling me? That mouse pube at 38 seconds says you are..... annndd then I was rick rolled.

[@BreakingTaps]

That piece of whatever dust really triggered me while editing... was tempted to refilm that specific part just to have a clean wafer. Sigh. Really need to make a clean-air hood or something 🙃

[@sfsinfinity5862]

Rickrolled by electrons. This is amazing.

[@michaelheal3600]

The art of peace is a piece of art-Heal

[@EvanZalys]

Nice video. Ice cold IPA/DI is a good call (see Rooks et. Al.) but we typically don’t puddle develop. We use vigorous agitation with the entire wafer dipped into a Nalgene bottle of IPA/DI. We usually dose at 1600 nC/cm^2. High acceleration voltages aren’t really necessary. We have an elionix HS50 designed for high current that tops out at 50 keV. Works great. PMMA in anisole is also a good call. I think you may be running into issues of the polydispersivity of your resist as you had suspected. You might be able to purify it!

[@EvanZalys]

Also I’ve been doing EBL for about 10 years and never once used PEC. Depends on what you’re trying to do, obviously. For josephson junctions for instance, you just do parameter sweeps until the room temperature resistance comes out right and the thing looks right under AFM.

[@BreakingTaps]

Cheers for the tips, really appreciate it! Will give vigorous agitation a try, and will look into purifying the PMMA (or just tracking down a bottle of the real stuff, can't imagine it's too expensive... I hope? 😅 )

[@EvanZalys]

@@BreakingTaps it's about a grand per bottle from kayaku :(

[@PeregrineBF]

Given your channel name, you might know that Electrical Discharge Machining (EDM) can be used to "drill" out broken taps, including those in rather soft materials like aluminum. It's also one of the only viable ways to drill out a particularly small tap, like a 4-40 or M2 tap. Could be a fun and useful rabbit hole to explore.

[@randomname4726]

That's neat to know, cheers

[@BreakingTaps]

Every time I break a tap, I go down the rabbit hole of looking into those little EDM "hole popper" machines. Seems like it'd be pretty DIY'able!