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Ink-Jet Printing Custom-Designed Micro Circuits
Nerval's Lobster writes "Researchers have demonstrated a technique that produces inexpensive, functional electrical circuits that can be printed using about $300 worth of materials and equipment, including generic inkjet printers. The technique, developed by researchers from Georgia Tech, the University of Tokyo and Microsoft Research, allows circuits to be printed onto irregularly-shaped materials or almost anything able to go through the paper feed on a printer designed for consumers. The chief advantage of the technique is the ability to print circuits using silver nanoparticle ink rather than relying on the thermal-bonding technique called sintering, which is time-consuming and can destroy delicate base materials. Researchers were able to print new circuits in about 60 seconds on almost any material that could go through the printer, though resin-covered paper, PET film and glossy photo paper worked best, while sheets of canvas cloth and anything magnetic were ineffective. Once printed using silver ink on flexible base material, the circuits can be attached to existing hardware by simply laying or taping them in place and making connections using conductive tape or conductive glue. (Soldering would destroy the underlying material.)"
Tape and glue. LOL. Does this have any real application outside of rapid prototyping?
zosxavius photography
They went shopping, bought a silver pen for handwriting electrical circuits and attached it to a printer???? (Although a plotter would be a better choice)
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Sounds a lot better than the home-brew technique I've use a bunch of times in the past: print the pattern on glossy photo paper using a laser printer, use a clothes iron to transfer the toner off the paper to the copper breadboard, then etch in acid bath. The part that usually screws up is transferring the toner from the paper to the circuit board using an iron.
Better known as 318230.
flexible, odd shapes that are resin encased. Hell think about scaling the units up. You could print a god damn PCB layers instead of the current etching methods. Less Polution and hazardous chemicals needed.
Other possibilities are as they said, flexible plastics (shit used for most cheap keyboards/game controllers) and don't forget OLED displays. Same technique can be used to print them (already being tested).
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But the inkjet cartridges will costs thousands of dollars each ...
>Hobbyists could also use the setup – which cost about $300 – to produce calculators, thermostat controls or other electronics as well, Abowd said.
Or terrorists could......
I know lets BAN inkjet printers
The folks at Hackaday have covered this many times over the past few years. Slow news day?
So they managed to make a flexible printed circuit that can't stand soldering. Not too useful.
There are lots of ways to make printed circuits. Etching them photographically is cheap, simple, and produces consistent quality, so that's how it's done commercially. The iron-on transfer thing some hobbyists use isn't that reliable; a substantial number of boards will be defective. There are little desktop milling machines for making circuit boards.
Nobody does that much any more. Commercial board making services take in a file on line and send back a board by FedEx. Prototype board prices today start at $28, so there's not much incentive to do it yourself. You get good quality and plated-through holes to connect traces on opposite sides of the board. The plating-through process is a mess to do on a small-scale basis, but cheap in bulk.
It might be useful in a few cases, but for most applications the quick turn pcb houses like expresspcb can turn a file into a circuit that is express mailed back in a couple of days for $100 with no human intervention. Since those are standard PCB materials they are reasonable prototypes for real systems.
If these circuits could be soldered it would be a lot more interesting. Too many modern components are in tiny packages that couldn't really be connected with tape or conductiv glue.
With the price of silver going up...who will be able to afford these circuits? Could they do some sort of reaction with...say...copper or something that would exchange out with the silver and leave the silver recyclable? Could they replace the silver with copper? I know silver is a better conductor, but, it would get cost prohibitive.
Rapid prototyping IS a real application. And from there, extremely low runs of custom parts. This would have been useful to me before I sent for 10 PCBs that had two wires crossed, because the normal ink printed tests didn't show the problem, as I couldn't run electricity through them. All I could do was test mechanical compatibility.
You're probably looking at $25+ or more per project just for that stuff.
I was pricing it out once because I have an essential hand tremor that prevents me from being able to solder.
File under 'M' for 'Manic ranting'
I was really interested until I read "tape and/or glue". Hell, if I'm going to use those items, I can probably figure out a better hack, without using electronics at all.
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Instead of printing $ilver nanoparticles$ on plastic which can't even be soldered - it would be much better IMHO to be able to print an etch resist material on copper, then process in semi-normal fashion.
This would be far more interesting if they could produce even low-performance transistors. But I suspect you'd want to start out with a flatbed, and you'd wind up focusing on non-flexible devices that you could build up through many layers. Interestingly, big, low-performance transistors would change some of the typical features of VLSI: you could do incremental testing (before layering on more circuits - perhaps even printing replacement devices if certain already-printed components didn't work. You'd probably also not worry as much about heat, since if your cpu is spread out over much area, its heat density is going to be n^2 lower.
My group has been looking into this for a couple of months.
Lots of laboratories have achieved inkjet-built circuits in the past, to the level of "proof of concept". To date, all of them require exotic materials or expensive materials or have relatively high trace resistance, or some combination of the three. None are suitable for low-end hobbyist application yet. The project from the article is a good starting point for interesting research.
The issue with silver ink is cost: silver ink is massively expensive, even by inkjet standards. To date AFAIK, no one has been able to lay down copper traces with good (meaning: low) trace resistance suitable for prototype boards. A lot of people are working on this.
Inkjet printers can be easily modified to accept thicker material by mechanically raising the head transport mechanism. This usually involves cutting something apart and inserting shims and spacers (machine-screw washers work well), but this is not terribly difficult. Then cut away the angled paper feed mechanism (that bends the paper from vertical to horizontal) and add horizontal rails to guide the media through the unit. Also not terribly difficult. You can then print on just about anything: phenolic, glass, plastic, &c.
Inkjet print heads use one of two mechanisms: thermal and ultrasonic. Thermal vaporizes some of the ink to accelerate the droplet, while ultrasonic uses a piezoelectric mechanism to "squeeze" the droplet out. Almost all printers use thermal heads, Epson being the notable exception. Check the specs to see if the unit you're using has the type of head you want & if your ink can withstand being vaporized without clogging the pores.
Clean unfilled cartridges are available from InkSupply.com for experimenting, and you may need a cartridge chip resetter to reset the counter to "full". You can directly lay down etch resist by using a wax-based ink such as Mispro Yellow.
I've got a modified printer next to me. You can use it to print just about any liquid onto any flat, thin material... and not just conductive traces. You can print fluorescent dyes, or solvents that make microchannel arrays in CD-rom disks (place in spinner to force a liquid through the microarray channels). A colleague at MIT claims that they are printing biologicals as well; ie - laying down micro-organisms on patterned nutrients. (NB: I don't know that the microorganisms are inkjet printed, his may be a hybrid system.)
Lots of potential for interesting research here.
What's the smallest etch resist you've been able to work with?
I don't make boards with my printer, my post was an overview of things other people are doing with the inkjet process. Google "inkjet PCB" will return lots of hobbyist sites that talk about it, such as this one.
I understand that laying down etch resist is a bit harder than my post would imply. The inkjet is accurate enough that the drops form a mosaic of circles with voids between, so the board has to be heated while printing (or after) to get the wax to flow-cover continuously. Also, prepping the board takes some experimentation to find the right method.
I use toner transfer, and can get roughly 8 mil traces, poorly. I haven't yet found the magical incantation to get good, high-quality traces with this method - or maybe I'm the only one looking at the results under a microscope. I suspect it depends heavily on the type of printer used.
Seems to me this is too little too late, for 300$ you can buy TONS of electronics and microcontroller boards and modules on eBay.
I bought some conductive silver in a pen years ago to draw circuits on various surfaces but it always turned out to be a waste of time and you ended up with an inferior mess anyways.
So you suck as as PCB designer? DRC check is PCB 101.
Conductive glue is $2 per syringe if you don't go through a supplier with a 3000 percent markup. http://www.ebay.com/itm/1-Pc-0-2ML-Silver-Conductive-Wire-Glue-Paste-for-Electronics-Repair-Applications-/390614991342?pt=LH_DefaultDomain_2&hash=item5af277c1ee
I was trying to think of a practical application for this in my life. The first think my mind didn't reject was a cell or wifi boosting antenna printed onto transparency film, laminated & kept rolled up when not in use. From the comments, it sounds like conductive tape or glue could be used to attach wires that would be mechanically secured by the lamination process.