Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

3M tape with anisotropic z-axis electrical conductivity

3m.com

Post reply on HN
Print view View original

51–60 of 146 posts

Re: 3M tape with anisotropic z-axis electrical conductivity

#51

Post by t_mann »

jlebar wrote: post #39
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

> A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. The relevant question isn't whether they make great products, but whether their stock is undervalued. We in the tech world are used to "great products" -> "stock price always goes up", but in the "real world" there's no reason…

And an efficient-market-PoV should, from an investor PoV, be put back on the shelve together with the other econ fairy tales like general equilibrium, rationality,... There's a reason funds prefer to hire STEM PhDs over economists.

Re: 3M tape with anisotropic z-axis electrical conductivity

#52

Post by markdown »

dxuh wrote: post #44
markdown wrote: post #27

Earlier quoted context omitted.

Their "prowess" saw DuPont give cigarettes laced with new toxic chemicals they made to their employees to test the chemicals effects. Every human on earth has Dupont chemicals in their blood that will never go away, but accumulate over the course of our lives. These are "forever chemicals" that never break down. When you die you pass them on. They are in the animals you eat, in the beverages and water you drink, they…

That Netflix link is not available everywhere and also quite time-consuming to review. Obviously it is also a dramatic piece rather than a (semi-)scientific. I had a brief look at the PFAS wikipedia page ( https://en.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_subst... ), which is what that Netflix movie seems to be about, but it's also quite wordy and the claims you make can not be found on there as-is. Maybe you wa…

https://www.popsci.com/story/environment/dark-waters-chemica...

Basically, the US government allows companies to sell new chemicals they invent, completely unregulated. You could make a toxin today that kills everyone who touches it 10 years after they ingest it, and you would be free to market and sell this product. The chemical is presumed safe until evidence to the contrary comes to the knowledge of the govt.

That's how Dupont poisoned people all over the world. They sold unregulated chemicals they invented that nobody but them knew about.

One report by the Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey (NHANES) found PFAS in the blood of 97% of Americans... The number of new PFAS chemicals appear to be increasing, and exposure is difficult to assess. - https://www.niehs.nih.gov/health/topics/agents/pfc/index.cfm

Re: 3M tape with anisotropic z-axis electrical conductivity

#53

Post by magicalhippo »

n4bz0r wrote: post #42

Could this be used for CPU (or some other truckload-of-pins chip) "reballing"? Does it do well under a bolted-on radiator / pressure plate? For instance, many old Playstation 3 systems go faulty because of the poor quality solder on the CPU/GPU that tends to crack over time. Being a normie, it's really hard to fix something like that at home. But this tape seems like it could save the day.

> Could this be used for CPU (or some other truckload-of-pins chip) "reballing"?

The datasheet[1] says the minimum gap between conductors is 0.4mm, so based on that it should work for 0.5/0.65mm BGA.

Also would clearly affect the speed you can run things at due to introducing parasitics. But would certainly be fun to try.

[1]: https://multimedia.3m.com/mws/media/66235O/3m-electrically-c...

Re: 3M tape with anisotropic z-axis electrical conductivity

#54

Post by mensetmanusman »

systemvoltage wrote: post #23
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

3M is an awesome company. I've worked with them to produce custom adhesives for us ($MM orders). Their products have exceptional quality, reliability and performance. What you see in a datasheet is what you're going to get (or better). 3M's consumer products (Scotch, etc.) are also excellent. Anytime you use 3M products, you don't need to worry. I like that consistency and it brings peace to the mind. I'll pay more f…

One cool thing now is that 3M releases finite element data packages for adhesive tapes, digital prototyping!

https://www.3m.com/3M/en_US/bonding-and-assembly-us/resource...

Re: 3M tape with anisotropic z-axis electrical conductivity

#55

Post by a9h74j »

addaon wrote: post #32
mrfusion wrote: post #29

Earlier quoted context omitted.

I don’t quite get how that’s useful.

Besides an occasional process improvement over soldering, this can be applied in cases where soldering cannot, for example with very heat-sensitive components such as OLEDs.

Perhaps also on stress-sensitive components such as high-stability voltage references.

Re: 3M tape with anisotropic z-axis electrical conductivity

#56

Post by bialpio »

dxuh wrote: post #44
markdown wrote: post #27

Earlier quoted context omitted.

Their "prowess" saw DuPont give cigarettes laced with new toxic chemicals they made to their employees to test the chemicals effects. Every human on earth has Dupont chemicals in their blood that will never go away, but accumulate over the course of our lives. These are "forever chemicals" that never break down. When you die you pass them on. They are in the animals you eat, in the beverages and water you drink, they…

That Netflix link is not available everywhere and also quite time-consuming to review. Obviously it is also a dramatic piece rather than a (semi-)scientific. I had a brief look at the PFAS wikipedia page ( https://en.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_subst... ), which is what that Netflix movie seems to be about, but it's also quite wordy and the claims you make can not be found on there as-is. Maybe you wa…

Not sure if you'll consider this a more scientific source, but John Oliver also did a piece about PFAS: https://m.youtube.com/watch?v=9W74aeuqsiU.

The list of issues that the wiki article claims are "high certainty" is also quite concerning to me: https://en.m.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_sub...

At the very least, seems that the production is being ramped down - quick skim of the article yielded this quote: "Their [PFASs'] production has been regulated or phased out by manufacturers, such as 3M, DuPont, Daikin, and Miteni in the US, Japan, and Europe."

Re: 3M tape with anisotropic z-axis electrical conductivity

#57

Post by djrogers »

timschmidt wrote: post #50
mardifoufs wrote: post #45

Earlier quoted context omitted.

Yep! But it sadly cannot replace soldering for denser pinout layouts, unless a lot of pressure is applied. Someone tried though; https://tomverbeure.github.io/2019/11/21/Z-tape.html (A bit off topic but that Bloomberg story is still such a mystery to me. It went into quite a bit of details and claimed it had tons of sources, so even if it was a completely false story whoever fabricated it must have put insane amounts…

It was also quite a plausible hack. The faker, if indeed anything was faked, knew more than most. Enough to have done the thing for real.

It was completely implausible - the chip that was identified could not possibly carry enough processing ability to do anything useful as far as espionage goes, had no connectivity to networking, and there was never any evidence of communication from these devices to anything suspicious or unknown.

Re: 3M tape with anisotropic z-axis electrical conductivity

#58

Post by steve_adams_86 »

systemvoltage wrote: post #23
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

3M is an awesome company. I've worked with them to produce custom adhesives for us ($MM orders). Their products have exceptional quality, reliability and performance. What you see in a datasheet is what you're going to get (or better). 3M's consumer products (Scotch, etc.) are also excellent. Anytime you use 3M products, you don't need to worry. I like that consistency and it brings peace to the mind. I'll pay more f…

3M’s consumer abrasives are also remarkably good. Not only are they more effective during use, but they last longer as well, with a much later falloff in abrasion quality. In fact, they last so long that their price (nearly double the price per pad in my case) easily justifies itself.

I have no idea what kind of black magic makes it possible but I’m so glad I gave them a try.

Re: 3M tape with anisotropic z-axis electrical conductivity

#59

Post by calvinmorrison »

systemvoltage wrote: post #23
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

3M is an awesome company. I've worked with them to produce custom adhesives for us ($MM orders). Their products have exceptional quality, reliability and performance. What you see in a datasheet is what you're going to get (or better). 3M's consumer products (Scotch, etc.) are also excellent. Anytime you use 3M products, you don't need to worry. I like that consistency and it brings peace to the mind. I'll pay more f…

3M, Johnson Johnson, Church Dwight, and a bunch of really householdy name companies are all smack in the middle of NJ. It's a sweet spot if you want to hop a few big corporations in your lifetime and work your way up the chain.

Re: 3M tape with anisotropic z-axis electrical conductivity

#60

Post by heavyset_go »

Brian_K_White wrote: post #38
heavyset_go wrote: post #25

Earlier quoted context omitted.

I take it the tape would go in the middle between the circuit board and components?

"I take it the tape would go in the middle between the circuit board and components?" Let me see... "place the tape on a circuit board and place components on the tape"

Thanks, without your constructive comment I would've never known that I was asking a dumb question.
Post reply on HN