I wonder if someone has figured out how to use inkjet or screen printing to make a simple wifi/bluetooth transmitter or an NFC tag.
So far I've only seen the antennas printable but not the transistor logic.
So far I've only seen the antennas printable but not the transistor logic.
I'd be surprised if an inkjet can't get higher resolution than screenprinting. Doesn't solve the transistor issue the OP was asking about though.
It's almost possible to inkjet print circuitry with transistors in research applications; see [1]. 20 micrometer resolution is relatively easy, so a WiFi/BT or NFC antenna (~millimeter scale) is very possible. I agree, the tricky bit is making (a) enough transistors to for the radio at (b) sufficiently high frequencies. As in [1], inkjet-printed transistor circuits have at most ~10 transistors as of yet (and NFC chips, with > 512 bit memory, need at least hundreds if not thousands). According to [2], inkjet printed organic transistors are in the range of MHz frequencies; NFC (~13 MHz) may be possible; WiFi (~2.2 GHz) may not be for a while yet.
[1] https://news.ycombinator.com/item?id=24129506 [2] https://doi.org/10.1021/acsnano.6b06041
In that Era the state of the art was multiple layers of ceramic substrate. Modern techniques like Volterra have allow you to print the ink and insulation. No reason it can't also print resistors. You can have a ten layer single sided board, printed in your lab in an afternoon. My only issue with it is the relatively poor conductivity of the conductive ink. But that will be solved eventually.