[Article] Solder-less circuits (apparently) - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: December 01, 2022, 06:18:14 pm
content: Wow, consider me... Amused. I think. Sounds like a wonderful way to generate e-waste and make thingseven lessrepairable. Not to mention that assuming that the entire industry would abandon solder is laughable (obviously)https://www.eetimes.com/solders-days-should-be-numbered-there-is-a-better-way/

author: Benta
author_rank: Super Contributor
timestamp: December 01, 2022, 08:02:28 pm
content: A 1000+ words saying... nothing. Not worth the read. Friends, save your time.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 02, 2022, 04:46:04 am
content: Quote from: eti on December 01, 2022, 06:18:14 pmI don't think the idea that all or a large chunk of the industry changing the way they do things is inherently laughable or unreasonable. The industry has made many major shifts over the years. But the linked article is pretty much content free even by press release standards, and doesn't say anything about what they actually do. There are some links to white papers posted in the comments section but if they can't be bothered to explain the basics of their technology I'm not going to go read their website.

author: tooki
author_rank: Super Contributor
timestamp: December 02, 2022, 07:37:08 am
content: There’s basically nothing on the website either.

author: ebastler
author_rank: Super Contributor
timestamp: December 02, 2022, 09:36:02 am
content: Well, there is a wee bit on information, to be fair:QuoteThe basic idea seems to be that they physically attach the components to a carrier, without any electrical connections. Then "encapsulate" them, presumably embedding them in epoxy or such to get a clean planar surface in the same plane as all the component contacts. Then make the connections by adding traces, in a process similar to what is used for making bare PCBs today.But indeed, where's the beef?

author: tom66
author_rank: Super Contributor
timestamp: December 02, 2022, 11:39:24 am
content: I can't see how you could achieve the density of connections for something like QFN or BGA. If this works - and that's a big "if" - it's going to be limited to the simplest circuits, unless there's some as of yet undisclosed magic process to improve the reliability and connection density.I'm also not sure how encapsulating everything in epoxy is supposed to reduce e-waste, when doing so will make it impossible to repair an assembly.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 02, 2022, 12:30:48 pm
content: Quote from: ebastler on December 02, 2022, 09:36:02 amPCBs are mostly made using a subtractive process. I suppose it might be possible to deposit copper onto a photoresist mask like is done for making chips.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 02, 2022, 01:47:15 pm
content: In about 2011-2013 Jennifer Lewis and others had a startup in Akron, OH for making circuits without solder. That is, additive PCB's. I can't find that news release, but her she is giving a lecture on it:https://www.youtube.com/watch?v=Sry17B8SYGk That process uses the well-known Tollens reagent with modified reagents. Here's her original publication in JACS:https://pubs.acs.org/doi/abs/10.1021/ja209267cI suspect the order of process is to attach components, make connections, then encapsulate as needed.

author: coppercone2
author_rank: Super Contributor
timestamp: December 02, 2022, 07:10:57 pm
content: well you can still mill it and use rubberized abrasives for cleanup then install PCB sections. Annoying trash like chip flip glue packagesSomeone is going to develop a repair tool that uses pace microchine technology to automill PCB and avoid mangling the metal too much, like a cleaning mill. I wonder if you can put a RF current into the conductors and then have the mill avoid the traces by detecting proximity to RF fields to remove 90% of the gunk and then hand polish away the rest after some chemical weakening using fiberglass sticks.Typical xenomorph problem.

author: hans
author_rank: Super Contributor
timestamp: December 02, 2022, 08:10:56 pm
content: Here is 1 patent:https://scholar.google.com/citations?view_op=view_citation&hl=en&user=6Q4QknsAAAAJ&sortby=pubdate&citation_for_view=6Q4QknsAAAAJ:Mojj43d5GZwCThe figures from fig1-6 depicts a few assembly steps. First components are placed on an adhesive sheet so they are all horizontally level. Then adhesive is applied on top and they are lowered in a negative template (machined or molded). The hole on top is to let excess adhesive escape. The adhesive around the parts are cured, and the sheet on the bottom is removed. How the adhesive finds it way around the part without leaving air bubbles, instead of all going through the vent hole is a mystery to me.This patent refers to the final assembly in which an anisotropic conductor is used:https://patentimages.storage.googleapis.com/fc/dd/f9/f31bfd82598b7a/US20090017264A1.pdfIt basically looks like some kind of a zebra strip material. I suppose the material has very small vertical conductive pillars that are distributed semi-randomly so that any top point can be find conduction to the bottom part of the sheet, but due to the small structure size does not short to nearby pins for a small pitch layouts.I do wonder though.. sure this may be solderless, but it looks like it removes all options of heatsinking for a kind of component. We don't know the thermal conductivity of the anisotropic conductor to the PCB, but I expect it to be fairly poor. The component is molded in, so it would need special provisions to add a heatsink afterwards. Since all electronics consume some kind of power, especially power supplies, I would see that as a major concern. Ironically the thermal stress is one it tries to solve.The website talks about the frame being an integral heatsink to the design. But personally I think: compared to a conventional heatsink, you now add a potentially relatively thick substrate and additional adhesive that needs to correct for machining tolerances of a whole PCB (instead of only the tolerance in 1 part). I don't think those 2 combined can be "better" than what we now have, as it was not it's initial goal. It would probably be very good in distributing the heat around the whole PCB though.Second I wonder about the structural rigidity. We still like through-hole mounted connectors because they can be much stronger than SMT. Sure the component frame may provide extra stability for the connector at the point of largest leverage, perhaps it can also add as a very good mechanical shock conductor and introduce new problems. It may not be solder related, but with respects to bad contacts, metal fatigue in braided wires, etc.And then clearly this concept isn't going to work for all components. Straight up connectors can't be covered by the frame, but how would it be secured in place? Right angle connectors only? Well, FFC connectors also require a lever operation so need to be partially free. Etc.I suppose it can work out, but I'm not convinced that removing soldering is going to suddenly make electronics a lot more reliable.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 02, 2022, 08:22:35 pm
content: Doesn't seem like something that would ever be cheaper, but maybe it could be more robust (the whole thing is potted in the process?) or compact (depends how you build the PCB layers I guess?), or maybe some obscure use cases where solder (leaded or otherwise) isn't otherwise applicable. Which is basically to say, a resin-based, printed/additive alternative to laser-etched ceramic hybrids? Finer pitch than screen printed (multilayer) ceramics?I don't see that it would ever be, like, super higher temperature rated, unless the resin is replaced with a low-fire ceramic that manages to not destroy the components (chip resistors could oxidize, chip capacitors could oxidize too, maybe other effects given their precise formulation?), let alone the silicon chips themselves. (Counterpoint: SiC chips.) But that wouldn't be printed I think; there are known ceramic-tape deposition methods that could be used to build that. Although... if it's getting fired, there must be shrinkage, I don't know how you'd get around that. So nevermind, I guess... But anyway, just to say, it's probably not an alternative to traditional metal-ceramic builds, with solder, braze or wirebond, for high temperatures.Tim

author: eti
author_rank: Super Contributor
timestamp: December 03, 2022, 12:40:35 am
content: I can’t see soldered PCBs being replaced by this. Ever.

author: tooki
author_rank: Super Contributor
timestamp: December 03, 2022, 02:26:44 pm
content: Quote from: NiHaoMike on December 02, 2022, 12:30:48 pmNot really. It’s not like home PCB etching which is purely subtractive. Commercial PCB production is surprisingly a mostly additive process these days. There are some videos by PCB manufacturers going through the detailed steps, and it’s quite different from what one might intuitively expect.

author: coppercone2
author_rank: Super Contributor
timestamp: December 03, 2022, 02:36:18 pm
content: it could be either one IMO, you just need chemical recycling technology for dealing with the byproducts to remake copper. Always efficency improvements to be made there.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 03, 2022, 02:46:15 pm
content: Quote from: tooki on December 03, 2022, 02:26:44 pmThe copper layer still seems to be done as a sheet that gets etched away. The solder mask and silkscreen are done with an additive process.

author: tooki
author_rank: Super Contributor
timestamp: December 03, 2022, 02:47:42 pm
content: Quote from: coppercone2 on December 03, 2022, 02:36:18 pmIf you’re referring to my prior post: It’s not about efficiency, though it benefits that too. It’s that plated through-holes are inherently an additive process, and they’re now omnipresent. Youhaveto do it additively.

author: tooki
author_rank: Super Contributor
timestamp: December 03, 2022, 02:49:43 pm
content: Quote from: NiHaoMike on December 03, 2022, 02:46:15 pmEven in that video, which does NOT cover all the steps in detail, they say that they have to “add copper”.The cladding on the bare boards is just enough to allow a clean etch. It’s then additively built up to the final thickness. This is necessary because played through-holes are necessarily an additive process.(Solder mask can be subtractive, using laminated-on film that’s then exposed and developed, or additively using a silkscreen process followed by UV curing.)

author: coppercone2
author_rank: Super Contributor
timestamp: December 03, 2022, 02:55:02 pm
content: there are down sides to reliability doing it that way vs rolled copper, in terms of surface finish and fracturability. The electrodeposited stuff cracks easier/differently (complex tradeoff). Lots of different way to get even the raw copper sheet for a etch, let alone additive manufacturing.optionsfor PCB raw stock, they like to dip a roller in a electroplate solution and spin it till it gets thick enough to cut off.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 03, 2022, 06:33:33 pm
content: Chemically deposited silver as described is quite shiny (it is still used for front surface mirrors), solderable, and flexible.

author: ebastler
author_rank: Super Contributor
timestamp: December 03, 2022, 07:28:40 pm
content: Quote from: NiHaoMike on December 03, 2022, 02:46:15 pmAh, right. I can see how thinking about additive processes reminded you of that video.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 03, 2022, 10:06:57 pm
content: You seem to suffer the same affliction for pretty, young, its, in skimpy clothes as NiHaoMike does. Just wait 40 years or so, and you will see the light.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 03, 2022, 11:56:51 pm
content: Quote from: ebastler on December 03, 2022, 07:28:40 pmA look inside a PCB factory, exactly on topic.

author: coppercone2
author_rank: Super Contributor
timestamp: December 04, 2022, 01:10:03 am
content: someones wife must have gotten on the computer

author: ebastler
author_rank: Super Contributor
timestamp: December 04, 2022, 08:20:36 am
content: Quote from: jpanhalt on December 03, 2022, 10:06:57 pmYou seem to read something into my comment which I neither wrote nor thought. I think Mike got my drift though.QuoteThat would be the heavenly light by then, I trust...

author: tooki
author_rank: Super Contributor
timestamp: December 04, 2022, 01:00:12 pm
content: Quote from: ebastler on December 03, 2022, 07:28:40 pm(I’m gay, so I’m immune to her sorcery!)

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 04, 2022, 01:03:44 pm
content: Quote from: tooki on December 04, 2022, 01:00:12 pmAnd she's a lesbian.

author: tooki
author_rank: Super Contributor
timestamp: December 04, 2022, 01:19:40 pm
content: Quote from: NiHaoMike on December 04, 2022, 01:03:44 pmGay men aren’t attracted to gay women any more than to straight ones.

author: coppercone2
author_rank: Super Contributor
timestamp: December 04, 2022, 11:31:33 pm
content: they should limit video making to black spheres that float

author: DavidAlfa
author_rank: Super Contributor
timestamp: December 04, 2022, 11:41:10 pm
content: Quote from: eti on December 01, 2022, 06:18:14 pmYeah, saw it yesterday. The whole article seems like a big noisy BS attempt.Apparently they're talking about some sort of electroplating.Repairing those must be a joke. Or they're trying to simply kill repairing at all.Quote from: NiHaoMike on December 03, 2022, 02:46:15 pmHonestly, I tried watching some videos from her, but nope.I mean, I love women, but I hate that behaviour.Look at my giant butt, sorry my teeets are blocking the camera!Give me likes!For example, I like a lot more Diana (Physics Girl), she's a kind of female version of Veritasium.

author: tooki
author_rank: Super Contributor
timestamp: December 06, 2022, 02:49:01 am
content: I was trying to find this the other day but failed, today I was successful.Isn’t the thing in the original post basically a rehashed version of this 1940s technology?