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How LEDs Are Made
An anonymous reader writes "The SparkFun team took a tour of a factory in China that manufactures LEDs. They took lots of pictures showing the parts that go into the LEDs, the machines used to build them, and the people operating the machines. There's a surprising amount of manual labor involved with making LEDs. Quoting: 'As shipped on the paper sheets, the LED dies are too close together to manipulate. There is a mechanical machine ... that spreads the dies out and sticks them to a film of weak adhesive. This film is suspended above the lead frames ... Using a microscope, the worker manually aligns the die, and, with a pair of tweezers, pokes the die down into the lead frame. The adhesive in the lead frame wins (is more sticky), and the worker quickly moves to the next die. We were told they can align over 80 per minute or about 40,000 per day.'"
Pretty sure that if I force my slaves...er...employees to work 12 hour shifts then they will do 57,600 a day...they can pee and have a meal after their shift is over in their cells...I mean barracks. CEO Lucky Good LED Industries CHINA
You have to expect that in a country where manual labor is cheap. In other countries, it makes more economic sense to automate or otherwise fix inefficiencies in the manufacturing process.
Any sufficiently unpopular but cohesive argument is indistinguishable from trolling.
Go to reddit!
We don't care!
The most striking thing to me about that .. article is that the factory was actually closed on a Saturday.
They aren't all 3D printed at home?
Luddites!
I suspect this story may draw comments from people who know something about LED manufacturing. If so, I hope someone can answer this question. I noticed that panels of LEDs, such as used for traffic lights or stage lights, are composed of 200 individual LEDs. So the process is:
Cut one LED panel apart, into hundreds of LED cores.
Glue hundreds of leads to the hundreds of fresh cut cores.
Align hundreds of cores into hundreds of little molds.
Inject resin into hundreds of little modes.
Assemble all of the hundreds of resin-covered LEDs back into a panel again.
Why not this?:
Attach ONE set of leads to the LED silicon panel.
Dip the whole dang panel in resin.
They took lots of pictures showing...the machines used to build them
Yes, they showed them alright, from nearly 10 ft away, without so much as a pointy arrow towards the part they are talking about, not that you'd be able to tell anything from that distance anyway. Seariously, they could be taking pictures of any random industrial machines and you wouldn't know the difference. I was hoping to actually SEE how they're made...considering that's what the title says...
beta sucks. When will it be canceled?
Machines may be more efficient, but they would need to be manufactured and run on coal electricity. Perhaps we should encourage handmade electronics for the time being.
So, SparkFun can be surprised that a labor intensive process is done in a place that pays employees not very much money? You do the lookup to see what China factory workers earn in a day or week and see how they live. It's nigh impossible to purchase a small appliance or even our favorite tech items that aren't part of this dark and dirty manufacturing scene.
Note: I am speaking as a material engineer who spent about 6 years in R&D for the 65W LED bulbs you can now buy at HomeDepot. The articled failed to mention the most important aspects of the LED manufacturing: wafering and the MOCVD that deposits the light emitting materials (the PN junction) onto the wafer. In short, the steps would include: 1) Crystal growth / wafering / surface prep; (make the wafer) 2) Nitrite epitaxial growth; (grow the light emitting part) 3) Wafer fabrication (cut big wafers down to die-sized chunks) 4) Packaging and testing (encapsulating the die) -- what the article was describing The article only touched upon the 4th step of LED manufacturing, and concidently, the most automated aspect of manufacturing, as well as the part that contains the least amount of patents / trade secrets. The first 3 steps were marginalized as "This is a sheet of LED dies. YunSun buys their dies from a high quality Taiwanese company". To my knowledge, there is no high quality manufacturer in Asia outside of Japan. Samsung makes a great quantity of ok stuff, and China / Taiwan makes a great quantity of shitty stuff that is ruining the entire high profit margin products. Also, all of the major manufacturers of LED dies dare not introduce step (2) and (3) into China / Taiwan due to IP issues. Wafering is important because larger wafer sizes (2in to 4in to 6in) means more dies per area. However, crystal quality becomes harder to control as sizes go up, especially for US-based LED manufacturers that is based on silicon carbide instead of sapphire. The real issue is with the MOCVD, the deposition technique that grows the PN junction which actually emits light. In the world of deposition, MOCVD is archaic voodoo magic and we spent a lot of time praying to deities of deposition that our process would repeat for more than a day. Fab is more systematic than epitaxial growth, and the real science here has to do with light extraction. Again, big money is spent on R&D here, and we dare not bring the manufacturing process to Asia (except for Japan).
Not just the production way is low-tech, this type of LED is depricated for everything but the cheapest crap available.
Modern LEDs are basically all SMD, the high power ones typically mounted on a solid metal core PCB. And those are acutally manufactured in a more modern type of way.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
...squinting at tweezers day-in and day-out for most of your life and the toll that would take on your eyes. It must be even harder for tall people with long arms.
I never did look into how LEDs are made (hey, I just buy and put them to use) and that it is a "cottage industry." And LEDs are made in open air facilities instead of clean rooms. I can start my own LED factory but unlike the author I don't have a basement.
mfwright@batnet.com
More liberal propaganda to justify our loss of lightbulb freedom
When I was last involved with lead it was treated as a hazardous material, gloves and a gas mask at the minimum were required when working with it, or around it.
That's funny considering probably a third or more of the stories here are lifted from reddit.
Go to a foreign country, get invited to take a rare trip through a valuable suppliers factory.
This supplier carefully dresses up for his guests, and makes sure his factory is spotless for the important, honored visitors.
And you show up in a ratty t shirt and wtf are they,capri shorts?
Nothing like showing respect for your hosts. What did you bring as a gift, a used newspaper you read last week?
-Styopa
The hell with that. I want to see how babies are made.
Oh, wait...
They were referring to "lead frames", the wire terminals and internal die supports used in a semiconductor package (before the plastic overmolding is done).
Nothing to do with the toxic heavy metal with the symbol Pb.
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I suppose that makes sense - if a CPU can have millions of transistors in less than one square inch, the wafer density is way to high to have only a few hundred diodes on a chip large enough to handle the heat. Unless of course much, much larger process sizes were much, much less expensive.
this is another factory with more automation.
https://www.youtube.com/watch?v=dDcMarYHknA
make light work!
Modest doubt is called the beacon of the wise. - William Shakespeare
I never knew this style of LEDs were mostly made by hand.
I always assumed it was done by an automated assembly line, like how (mostly) CDs and DVDs are created on automated assembly lines.
Now would enjoy it, if someone could tour a LED light bulb factory, and share how those are made.
Uh, Linux geek since 1999.