Inside a Huge PCB Factory - in China
Inside a Huge PCB Factory in China

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Today we're visiting JLCPCB (, one of the largest prototype PCB manufacturers in China. We're getting an exclusive factory tour of one of their newest printed circuit board factories in Huizhou, just outside of Shenzhen, to see the PCB manufacturing process step-by-step. Are you an electronics geek or a DIY enthusiast that loves soldering projects that's always wondered how to make that PCB? Today we're going to see how it's made! Thanks to JLCPCB for sponsoring this video! Share this video: Subscribe to the channel here: Edited by auram - Gear for this video: Main camera: Main lens: Other camera: Microphone: Wireless microphones: Audio Recorder: Facebook: Twitter: Instagram: Music: Shlow Motion Pt. 2 - oomiee (Licensed through Epidemic Sound) Young Bones by Jake Maynard - Calaveras (Licensed through Art List) Water - Seamus Mcnamara (Licensed through Epidemic Sound)


James Kim : I think Lily really enjoyed the tour of the factory, she learned a lot from the tour guide.

Jr Sarath : When you know everything - SHE : Yeah

BiggityBoggityBoo : Why are people complaining about him repeating everything she said? He's doing it on purpose so we can fully comprehend and actually hear what it is she's saying. Without his commentary I would have missed a lot of what she was saying and had to replay and turn things up just so the details weren't missed. His repetition is also for clarification, so that something hasn't been lost in translation. He repeats back to her what he understood about what she said, so that something wasn't misunderstood.

lespaul36 : I love that you used JLCPCB. I had a design I wanted made and since I am used to stuff from China taking a while I was cool with that. Their shipping options were all a rush shipment for me in the USA. So I was bummed because the expense of the shipping wasn't worth the expense for a non commercial board. I messaged them saying I would love to use them but the shipping was high for someone like me as a hobbyist. Unlike any company I have dealt with, they responded saying that they wanted to add more economical shipping and actually did it. I am waiting for my second order and totally happy with my first. I really expected sloppy work, and got a great product. They also sent a pen (I am sure for advertisement) that was awesome. I highly recommend them.

Bassem B. : Is she giving you a tour or are you giving her a tour? Haha :D fascinating factory, great video, documentary level!

Nori-Atnep Lynobrac : The PTH (plating through-hole) process is very complicated but I'll try my best to describe what's happening. ----- DESMEAR -----{1,2} It all begins with the desmear which usually consists of 3 different process baths and is necessary for two reasons. First of all, one has to remove the so-called smear (all the stuff that forms due to high temperatures during the (laser)drilling process), debris and dirt. The other reason for the desmear is to roughen the surface so that the deposited copper adheres better. The first bath in the desmear process is called sweller and contains chemicals that permeate into the cavities of the base material (the glass fiber epoxy resin composite) thereby letting the base material swell up, hence the name. The second bath is often referred to as the actual desmear and contains a concentrated solution of alkali permanganate and hydroxide. Under these conditions organic materials, such as the smear, decompose and glass is etched back. The third bath contains reducing agents that help to get rid of permanganate and manganese dioxide residues. ----- PRE-TREATMENT ----- The next process step is usually referred to as the pre-treatment. It is composed of up to 5 process baths. Please keep in mind that i'm only explaining the most common type of process which is an ionogenic palladium activation process (other activation processes such as colloidal palladium (as explained in a recent video by applied science) and direct plating processes that work without any but one pre-treating bath also exist and are used in the industry). (1) Conditioner The conditioner contains chemicals that help the activator to bind to the surface of the base material and copper. (2) Etch Cleaner The Etch Cleaner contains agents that remove oxide layers on any superficial copper. (3) Pre-Dip This is a bath containing chemicals that protect the activator from drag-in and helping the activator to get even into the smallest VIAs. (4) (Ionogenic Palladium) Activator The activator basically contains cationic palladium compounds that can bind to the base material. Check out the palladium price in order to understand why this process is so expensive. (5) Reducer{3} The reducer contains reducing agents, that reduce the cationic palladium [Pd(2+)] to elemental palladium Pd(0). This is important in the subsequent step, as the Pd(0) acts as a catalyst. ----- COPPER PLATING -----{4} Following the pre-treatment comes the electroless copper bath (ECB). This bath is used to deposit a thin layer of copper (usually around 1 µm give or take) that makes the whole PCB conductive so that it can then be plated in a conventional galvanic copper bath. Besides copper the ECB contains a reducing agent, alkali hydroxides and complexing/chelating agents as well as often stabilizers. The Pd(0) on the surface of the PCB catalyzes a chemical reaction in which the reducing agent is able to reducer the cationic copper Cu(2+) to elemental copper Cu(0). Since this reaction is autocatalytic it keeps on going once the palladium is covered in copper. However, the copper deposition using an ECB is very slow, expensive and doesn't give a nice surface finish. Therefore, the PCB is only treated for a short period of time and a galvanic copper bath is used in order to plate the desired thickness (commonly around 25 µm). The galvanic copper bath contains different chemicals (called leveler, brightener and suppressor) that help with via filling, surface finish, etc. . Keep in mind that the overall process leads to an entirely copper covered PCB so structuring is once more necessary. Afterwards the superficial copper tracks, pads and so on are covered with tin in an immersion tin process or with gold in a nickel/gold process. This is necessary because soldering to the bare copper is very difficult since copper oxide layers will trouble the solder adhesion. ----- References ----- {1} J. Kirmann, X. Roizard, J. Pagetti, et al., J. Adhes. Sci. Technol., 1998, 12 (4), 383–397 (doi: 10.1163/156856198X00100). {2} K. L. Mittal., J. Vac. Sci. Technol., 1976, 13 (1), 19–25 (doi: 10.1116/1.568850). {3} O. A. Sadik, H. Xu, A. Sargent., J. Electroanal. Chem., 2005, 583 (2), 167–175 (doi: 10.1016/j.jelechem.2005.05.013). {4} M. Paunovic., Mod. Electroplat., 2010, 1, 433–446 (doi: 10.1002/9780470602638). If you don't have access to these publications, try using sci-hub... looks dodgy, is used by many scientists=)

mikami sham : Incredible video, I'm Chinese, I also find Lily's English is limited, so I'm so thankful Strange Parts translated them into English-friendly language. THIS, is like what I'm seeing in Discovery Channel!!

Ooga Booga : Normal people: Wow what an amazing video, I sure learned a lot! Me: haha at 9:00 she says peepee

reda Khaidar : 23:20 Windows XP never die XD

off roader : Really enjoyed this Scotty. You've produced content on par with the quality I would normally only be able to watch on a BBC television documentary. Thank you for your hard work and I look forward to seeing where you go next.

sdguy123 : You were kinda freaking them out with the constant sudden hand movements.

S/V Tattoo : A Chinese factory with quality control, safety first, no slaves or children in sight, and nobody jumping out windows. Thanks for showing what factories in China are actually like, and not what the news in an unnamed country would like us to believe.

Stevens Garage : Next vid: Factory tour of the factory that makes the pcb drilling machines. They look insanely complicated

Lazy Bunny : Great video, only just now saw this. TBH, checking out the JLCPCB website, those prices are really good. And i mean Really Good.. So i'll actually probably be ordering from them pretty soon. Since i'm getting tired of DIYing proto boards.

Xavier Ancarno : Please go to a battery cell factory - Lipo or Li-ion

renyin wang : You should go to the Huawei headquarter in Dongguang city! It amazing!

Jamie East : should add component placement also. any type. fully functioning circuit

宋家樟 : Am I delusional, or this guy talks a bit like conan o'brien. Anyone else think so?

MDW8 : Mr. Liew has the personality of a PCB

Brock Elmore : How it’s Made with actual personality! Awesome, keep up the great work Scotty.

AW Photographic : Chinese are amazing people. Hard working and so clever. We wouldn't have half the gadgets we use today without china

Dave Lick : I totally get the reason why she says yea and you explain the tour, You both made this a very enjoyable experience. Thanks

Anthony LoPrimo : Amazing video and I'm glad I was able to see what the process is like. I have only one complaint/remark on the video... FIX THE MASTERING!!! I have the volume increased so I can hear you and the others, and then the music kinda jumps up super loud! It's like commercials on TV, haha... The show is really low, and the commercials are super loud lol

Keith Handy : This process is so satisfying to watch. I just placed my second order with this company.

Victor Panunzio : I freaking love this. The content, your sheer enthusiasm, everything in this channel is something I never knew I wanted or needed in my life. Thank you man. I’d love to see the process of making a GPU in a factory

A H : Wooow I am impressed with how complicated is the process and the amazing quality assurance. World class work China!

ObsoletePowerCorrupts : 2:40 The (corrosive) "strong alkali" photoresist might be Sodium Metasilicate.

EdWilsonPhoto : Coming to very much admire the Chinese , their energy, motivation, and smarts.. Thanks!

Velo1010 : I don’t think her real name is “Lilly”.

illiteratebeef : The background noise was rough and youtube's auto subs sucks, so I subtitled the video for you.

Erk Sampat : So happy to see this video on JLCPCB's website!

Victor Savelle : Great video. Yes she said "yeah" a lot, but it was prompted almost every time. She is very polite. Camera work was great, I got a bit lost in the process here an there, but it was very thorough. You're learning very fast, sir. I see the leaps ahead in quality, even though this minidoc is a newer format for you. My CC is in a case like this (where you take over the explanation of a scene), don't confirm each explanation, finish with a downward inflection. You did that sometimes. Overall, great work. I do like to offer CC because a "dope vid" only gets you so much info.. ;)

Руслан Андр : Ухх и клево же )) половину правда пришлось додумывать, ибо не понял.. Но супер!!

peter shchepin : I’d like to see a tour of an assembly proses after PCB manufacturing.

Catherine Green : Cool, thanks for sharing!!! I am really interested in PCB manufacturing. As I know, Shenzhen Mincom pcb manufacturer is great as well, hope someday you can make a review of it!!!

Alice : I really like this video. It's very help for me. We usually introduce our fab. to our customers/auditors and this video give us a good example to how to explain the processing methodology. And if you also show the inspection way, frequency and sample size, it'll be the most perfect on the earth. Looking forward to next line tour video.

Rodrigusificacionn : Is Connor McGregor showing us a factory.

Amfamora : He reminds me of Conan O'Brien Did you See Lily roll her eyes at one stage heh Good video though

Yuan Zong : This is amazing. I am working on a project related to PCB. This has been so helpful!

Blade Jade : Really good video showing PCB process. Could you advice the dark room lamination degree to avoid filming to the PCB? :)

jonka1 : Oh Dear. All that effort and co-operation from the company and this is what we get. Thank you to James Kim for his superb comment.

Eric Peltier : Great video, Scotty! I knew a few things about how multi-layer PCB boards were created, but to see ALL the steps is SO cool. I have no idea how they do Inventory Control at that speed!

nikhilesh garudapally : Well. it looks like you are giving her the factory tour. You have amazing knowledge.

connie xu : jlcpcb is mad with the price,not sure the quality

akrinah : Don't know whether she guides you through the fab or you guide her :D But I'm happy you explained it. She is not that easy to understand. I must admit, no Chinese would understand if I tried to speak my little bit of Chinese :D

Adver Space : The lady said the word ‘YA’ over 250 times,.. I counted,😂😂😂 She hardy said anything rather than YA, great video.....

Djo Tiger : 25:00 the guy on the right was like : "i dont even know what this blond guy saying but since his smiling i gss its a good thing" LUL

DaKatz : Are you giving the tour or is she?

Wisnu Wardhana : you can use english when you talk to us and use mandarin when you ask or interviewing them, then you can add the subtitles so they not struggling to explain #imo