In 2006, Hitachi developed a 0.15mm-sized RFID chip
hitachi.com110 points by julkali 6 days ago
110 points by julkali 6 days ago
The most amazing thing about this (and another tiny RFID chip that was on HN recently) is not that you can print them on wafers, but that you can cut up the wafers and handle these tiny dies. Imagine you manufactured sugar, but had to manipulate each sugar grain separately.
It thought it was an interesting analogy, so I looked up the size of a typical sugar crystal. It's between 450 and 600 microns. So these chips are 3 to 4 times smaller than that even.
I was in a project with MAN Roland and the university of Dresden at the same time and the most important thing is roll to roll printing. This actually works well if you do not need an external antenna. What was the holy grrail at the time was to print also the antennas, get a decent coupling and then actually also do item and not only batch level tracking of the packaging you would print. Particular Pharma was really interested in terms of anticounterfeiting at low cost.
I have always wondered how this works (along with wire bonding), especially in an economic way.
Chips being cheap makes sense at the lithography / wafer level because sure, you can stamp out thousands of them at once. But once you need to dice them up, bond wires to them, and package them... how on earth do you do that so efficiently that each chip can be sold for fractions of a cent?
Packaging used to be a huge portion of the industry, in the 80's when pin counts exploded and litho got cheaper it was usually the most expensive part of a chip.
Today, it's cheaper mostly because of flip chips and Wafer Level Chip Scale Packaging (WLCSP). You build the bond pads as a normal litho step, and use a dielectric that's non-wettable between them. Then you can just use a mask to produce a grid of solder balls in the right places, drop the chip on them and put it in an oven. When the solder melts, the chip will self-align on it, so long as it's not too far off. It's uncanny to see it move.
Lots of automation. Dicing is automatic, bonding, testing are automatic. The manual work is mostly just transporting materials.
The bonding machines are crazy. Definitely look it up on YouTube, the machine puts down bond wires super fast.
The other part of it is sheer scale. Once you start making thousands or millions of something, economies of scale drive the costs way down
Bond wires really are a thing of the past now except in niche applications or legacy chips. Flip chip designs have the die directly interface with a substrate that is then soldered to the board. With the kinds of speedy signals modern chips use, bond wires introduce impedance mismatch that degrades quality. This is related to why you don't see many new designs using pins.
And for reference there's a section in this BBC film about how it was done in the 1970s, by hand: https://www.bbc.co.uk/programmes/p01z4rrj
If you can shine lasers at them to etch out a chip trace, then you can shine lasers to carve up the chip. Just use stronger lasers.
Well, these ones are RFID chips, so they don't need to be connected at all - they are read wirelessly.
If you want the bare chips and not full assembled labels the usual packaging is uncut wafer and cutting out and handling the individual dies is your problem.
> If you want the bare chips and not full assembled labels the usual packaging is uncut wafer and cutting out and handling the individual dies is your problem.
This does not match my experience, although I imagine it's true in some parts of the industry. I've seen bare dice usually delivered as KGDs (known good dice -- tested at the individual level, not just the wafer level). These used to be shipped in waffle packs, but I've more recently seen blue tape used for delivery, and going straight into pick-and-place.
This is the really interesting Thing!!!! And: how they can have different ROM content (code) for each chip
How big is the saw if you're cutting up 150 micron pieces of wafer?
Sometimes a diamond saw is used but modern processes use lasers to score the die and then the wafer carrier expands to break along the scores.
Still needs an antenna tuned to the RFID frequency which will be much larger than the chip. It's cool engineering but doesn't mean you can have a working sub-mm tag.
No, but the chip does usually put a cap on the thinness of the whole assembly (e.g. for cards). This means you can have a paper-thin NFC sticker (which we have now, I guess).
The chip is still the majority of the cost of the inlay, so making a smaller chip is the key to driving total down and unlocking new use cases.
Also, you can find previous announcements of Hitachi's μ-Chip series. In 2001, evidently, they put out a 0.4 mm x 0.4 mm chip.
Not being programmable at all and just transmitting a 128 bit number would help get the size down.
Let's compare to a Monza R6 chip that was introduced in 2014, I think. This thing is 0.464 by 0.442 mm according to the datasheet, so quite a bit larger even than the 2001 read-only μ-Chip.
But it it has a two-way communication with the controller, and writable memory. You can enable password protection and such.
The newer M800 series is smaller: 0.247 mm × 0.362 mm, but still larger than the 2005 read-only μ-Chip. There are more features: fatter datasheet. Things like a privacy mode: tag remains radio silent unless it sees a specific 32 bit code from the reader.
You know how you can hold a totally unrelated RFID tag to a door reader and have the reader beep, indicating it has communicated with the tag? This looks like the feature that would prevent that. That could be useful.
> tag remains radio silent unless it sees a specific 32 bit code from the reader.
So you could spray sticky rfid chips into an enemy’s hair, undetectable when scanned, and later on you could send the correct signal to identify enemies in the room. Later their hair would be trimmed, leaving no trace.
Aside from the cool privacy aspect, it seems like it would be cool to:
- Attach to insects to later use a detector to find their homes.
- Coat it and eat it to track your digestion.
- Use it in a miniature tornado model or wind tunnel along with a radio spectrograph to have cool visualizations.
- Embed in paintings, 3D models, clothing labels, and more to verify authenticity, get serial numbers, or track inventory.
- Drop a trail of them behind you so others can follow the trail and find you!
In an early example of conspiracy theories that would eventually envelop social media, I actually remember internet commenters pointing to the previous generation of these as supposed "proof" that the government was embedding RFID chips in banknotes to track people (following a blog article by Alex Jones): https://news.slashdot.org/story/04/03/02/0535225/do-your-20-...
If I worked for VISA's marketing team I'd want to spread FUD like this and "XX% of dollar bills have cocaine on them; protect your children with a youth MasterCard!"
For those not familiar with using powered drugs nasally, a credit or debit card is also usually a part of the drug taking toolkit. Its one of those odd occasions when you need both cash and credit.
You usually keep the credit card though and not hand it to someone for a drink 5 minutes later. Using banknotes is not advisable anyway. If you need to do this shit be smart about it.
True and so probably a lower percentage of cards have cocaine on them, but they do share contact points such as swipes and touches.
There has been legitimate interest in putting RFID chips in high denomination Euro bills. It's not a whacky conspiracy theory but something actively being considered.
Honestly I would welcome it in all bills. Cash drawers could become self accounting, and bill sorters and talliers wouldn't have to rely on magneto optical sensing
What never cease to amaze me with conspiracy theorists, is that they keep inventing preposterous “conspiracies” while being totally oblivious about the real world. Like why bother putting chips in banknotes when the government could track everyone in real time through their smartphone.
Sure, but in this case the /. comment was from 2004.
And phone tracking and recording was in place since phones went mobile. Sure, nothing smart there but BTS were there, and NSA was listening on all levels.
CIA/NSA perfected the art of tapping optical undersea cables using special submarines without interrupting data flows in 90s IIRC.
This is what is in euro bills right?
Years later we put a newer version of this chip with a secure element into Bitcoin bills.[1]
Hand waiving a lot of the details, each note basically becomes a hardware wallet with some additional features to prevent double spending.
This is cool, I thought of something similar, didnt know someone implemented it and the swizz like bank note design is neat.
but its still has flaws imo and just makes it a novelty rather than something practical or useful, for example unless the vendor has change, you would have to spend your btc cash denomination as a whole or exchange it for fiat. what if both the vendor & customer didn't have internet access, how would they check if the cash hasn't been used? idk if you can write back to an rfid that may solve some problems
Are you involved in the project? I assume this is essentially a paper-thin HSM/Yubikey, right?
Is there any way I can use these as general-purpose HSMs outside of bitcoin/cryptocurrency contexts? Just as a novelty.
Let's say I just want to store a private key on it and use it for SSH/etc authentication - would that be possible?
With respect, this gives me serious ick. Black mirror vibes.
honestly given how long ago that was I'd not be surprised if everything's completely peppered with chips... one from the manufacturer, one from inventory, one from logistic, one from corporate espionage agent, one from foreign adversary state actor sky really is the limit with these. didn't parmesan put some chips in their cheese too?
Sounds crazy but car and truck tires have had RFID chips for years. I assume most people would be surprised by that.
https://www.tirereview.com/michelin-connect-car-tires-rfid-2...
Stealing people's tires is a common thing. So add an RFID reader to cars with ALPR gear, and they can see if any tires they come across have also been reported stolen. See, it's nothing but wins for the consumer!
Ah yes and then you can sell tire usage subscriptions: model XYZ can only be driven with an active monthly subscription
Imagine if the crazies were right and the Covid vaccines actually did have RFID.
Wouldn't that confuse someone if they were to be scanned and had multiple IDs because they received more than one vaccine as time went by?
The RFID vaccine conspiracy was inspired by another, very different technology Bill Gates helped fund - microneedle vaccines with quantum dot records. I guess RFID was easier for people to understand and it became the go-to conspiracy instead.
https://www.scientificamerican.com/article/invisible-ink-cou...
The RFID vaccine conspiracy theory has been around since the 90s, back when Bill Gates was just a software robber baron, before his Lex Luthor arc.
Is it possible to buy and use such tiny chips?
Used to develop readers based on similar UHF chips (868 MHz in EU). They were quite expensive compared to printed bar codes those were replacing. Also large. With (folded) antennas we are still talking about 40*10 mm minimum for the label. You can not use them on metal surfaces. Readers nearby will interfere as it works by EM wave backscattering, unlike NFC which is essentially a transformer (with electric field intentionally supressed usually). I think it still is a solution looking for problem. QR codes are cheap and NFC (14 MHz) readers are everywhere.
I have a hobby project where I am using UHF tags for counting poultry. The advantage that it gives me is long range (few meters) compared to LF / HF tags. QR code also wouldn't work due to size and distance.
Here's a video.
This looks immensely useful
I've been thinking about ways to count my chickens, making sure they return to the coop and don't get locked out at night. Most of the time all tge birds get in, but occasionally some will dawdle and wind up sitting outside a locked coop door.
You mention this can read for a couple meters. Can it read all the members of a flock, so I could mount a single transmitter in the ceiling if the coop, or is it one at a time, so something that should live above the door
I haven’t played with any stationary antennas but I think it’s possible.
The scanner that is used in the video has configuration for transmit power. At its maximum setting, the range is 15 feet with clear line of sight.
Tags with larger antennas, generally speaking, have longer range but might be too big for younger chickens.
So overall there are a lot of variables.
Really nifty; can I ask what tags you are using? (are they off-the-shelf)
Would be interested in doing something similar
I did work with that recently. Did a few cool demos.
The tags got cheaper and you can even get tags that are intentionally designed for metal surfaces. Unlike NFC (or barcodes, obviously), you can read hundreds of tags essentially simultaneously. But because the reading is far from being perfectly reliable (one thing we found out is that human body blocks the 868MHz RFID completely, even at something like 50dBm EIRP, which is well above what is considered safe for human presence) the applications are indeed somewhat limited.
But apparently there are two classes of applications where this technology is really common: libraries and bulk checkout at sports equipment retailers (seems oddly specific). Both of these things also benefit from the "advanced" features of UHF RFID tags like dual-mode RFID/EAS tags and ability to permanently deactivate the tag by simple command.
When you say "bulk checkout at sports equipment retailers", I guess that you might be referring to Decathlon, that has been adding unique UHF tags to every product for years, both for stock control and checkout.
Anecdote about it, 2019: https://mastodon.social/@russss/102674489508219187
shopping at uniqlo is really nice where you can just dump everything you want into the scanner
https://www.huayuansh.com/uniqlo-global-stores-applied-rfid-...
So that's what's in the smallpox vaccine.
presented in 2005 World Exposition, a time where hydrogen fuel cell was the whole future.
Oh, great. The New World Order can easily slip these into a dose of vaccine and you can be tagged for tracking without ever knowing it!