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I find it amazing that litography is considered a "simplification of the manufacturing line" compared to century-old technology that essentially consists of win
by the8472 6y ago
I find it amazing that litography is considered a "simplification of the manufacturing line" compared to century-old technology that essentially consists of winding a coil through a magnet. Granted, it's not a bleeding-edge fab process, but it's still a very strange view that considers this a simplification.
- quotemstr 6y agoWhy wouldn't it be? Winding a wire over a coil requires robotics. Making large, complicated 3D objects is finicky, slow, and expensive. Lithography is relatively simple --- it's a uniform batch process. Lithography nodes are complicated and expensive to research --- new nodes require brand new technology and even science --- but once you have a lithography line set up, you can run it over and over and over and over again, because the actual batch process is relatively simple and uniform.
- the8472 6y agoSo winding the coil requires robotics. And any lithography process requires robotics, cleanrooms, aggressive chemistry, vacuum chambers and whatnot.
- quotemstr 6y agoYes, but coiling stuff requires more complex robotics and a robot per coil, since you can wind a wire around only one coil at a time. With big lithography processes, your robot can be simpler (since it doesn't need to reach around or inside a complex shape) and it can process thousands of devices (on a big wafer) all at once instead of individually.
- megous 6y agoWinding a simple coil, like the ones inside speakers, requires just fixing a wire and rotating the core: https://www.youtube.com/watch?v=Np3wogoUsjc https://www.youtube.com/watch?v=Np3wogoUsjc You can make the same maching with many parallel winding heads + cutters and make as many coils as you like in parallel.
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- adamweld 6y agoThis is absolutely not true for the miniaturized balanced armature drivers that this MEMS speaker design is competing with. The coil must be wound in-situ and is usually epoxy potted due to fragility. https://navcomm.eu/img/cms/BA%20opis.jpg https://navcomm.eu/img/cms/BA%20opis.jpg
- megous 6y agoHmm, that's quite a different kind of a beast.
- deleted 6y ago[deleted]
- regularfry 6y agoI would suggest hitting up "speaker coil winding" on YouTube if you think this requires robotics. Sometimes the simplest thing is "pay a human $8/hour". You don't even need to spend millions on a litho node to make it work.
- kazinator 6y agoThis is about miniature speakers, like in ear-buds headphones, not Celestions for your guitar cabinet.
- willis936 6y agoYes but if you want a million an hour, that’s $8 million/hour. Suddenly photolithography seems incredibly cheap.
- zaarn 6y agoDoes it take an hour to wind a coil? Probably not. At worst, a minute for an experienced worker. That gets you to 130'000 $ per hour and 0.13$ human cost per device. Though a minute is very optimistic, you don't need that many windings, if you get it down to 10 seconds, which is a lot of time to wind a coil, you pay 22'000$ and 0.02$ per product. That's fairly cheap and if a robot can do it for less becomes questionable because robots need a lot of maintenance and cost a lot.
- willis936 6y agoWhat if you want 100 billion an hour?
- regularfry 6y agoThen you're screwed no matter what process you use. 100 billion 1 gramme devices is 100,000 tonnes. Per hour. For reference, that's about half the discharge rate of the Rio Grande.
- jononor 6y agoBatch here is the key. One can make 100-10'000 elements at the same time. This using the same equipment and processes that is used for fabrication of other MEMS sensors, techniques that are proven to deliver sub-dollar end-user costs for high performance microphones, accelerometers, temperature sensors, etc.
- Florin_Andrei 6y agoI think OP was referring to the fact that coil speakers are something that Isaac Newton could have made, if he knew how, whereas solid state is just not doable without modern tech.
- regularfry 6y agoIt's clearly not a simplification of the manufacturing line, but I'd consider it a simplification of the final object.
- jacquesm 6y agoFrom a personnel point of view it is a simplification. A robotic line that produces 10x the number of devices with 1/100th the number of personnel may well be worth the capital investment and once it runs it's a black box. Vs the complexities that you get with traditional manufacturing where a lot of the work is so complex that it can not yet be roboticized. If the final product is more geared towards automatic manufacturing that is in fact a form of simplification. I'm quite curious how these sound in practice compared to similar weight/size regular devices. Headphones and cellphones would be an obvious first application.
- kazinator 6y agoIt's the same way that a photocopy machine is a simplified document reproduction system compared to arranging die metal cast printing blocks onto a plate, etc. The photocopy machine is complex, but that's the photocopy machine manufacturer's problem, not the problem of someone reproducing a document.
- adamweld 6y agoI wonder if those that disagree with you have taken a look into the speaker drivers that this MEMS speaker targets (smartphones and earbuds). These devices are many times more complex to manufacture than the large scale dynamic drivers you might find in a pair of desktop speakers, and are definitely not possible to wind by hand. The armature is made with incredibly fine guage wire around a form of precise (non circular) geometry, and needs to be coated with epoxy to stay together. The diaphragm, reed and driver body are also precise parts with their own manufacturing difficulties. In short, I absolutely agree with the article's assertion that replacing these manufacturing methods with lithography is indeed a simplification. Just because the concept of a wound electromagnet has been around for longer does not mean that it is simpler in practice.
- baybal2 6y agoIf you read the article, there is not much lithography inside. It's mostly piezoceramics
- willis936 6y agoIt’s an idea that’s older than photolithography. https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf