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I've put the word etching in quotations as the method to get conductive tracks on a glass or plastic film might not involve a subtractive approach as with traditional PCBs of applying a conductive layer (such as ITO in this case) and then removing the unneeded part, but rather an additive approach such as printing or drawing the tracks on a transfer medium sheet and somehow transferring it to the glass or plastic (such as PET) film, etc. later, or printing/drawing directly on the glass or plastic film somehow.

Need two transparent conductors in an arrangment like this on a transparent plastic film. Such as ITO on PET. But it doesn't have to be ITO necessarily.

enter image description here

Of course for others it can be anything else such as this.

enter image description here

There are too many tracks and their size and their gaps are going to be sub milimeter, so hand drawing is out of the question.

Will be running few milliamps and about 8 VDC. Size of the whole film is going to be 10 cm x 5 cm max.

Since one may need to run dozens or maybe hundreds of tests with different widths, gaps and arrangments, is there is a way to print conductive material on a PET or similar transparent film at home, such as with a modified laserjet or inkjet printer, or a modified mini CNC? What can/should one use for the transparent conductive "ink" and the film and what should one use to get their drawing from a digital file onto real film/glass?

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closed as unclear what you're asking by Trevor_G, DerStrom8, Sparky256, PeterJ, Voltage Spike Jan 3 '18 at 22:50

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ change the word from "etching" to "laying" \$\endgroup\$ – jsotola Dec 29 '17 at 17:56
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    \$\begingroup\$ eeek.. my eyes.... \$\endgroup\$ – Trevor_G Dec 29 '17 at 18:06
  • \$\begingroup\$ What chemical properties are necessary for the conductive tracks (ITO) in this "capacitor" geometry? What dielectric properties? are needed for insulator (PET is well known to be low leakage). ITO is usually vacuum sputtered over a mask removed after. \$\endgroup\$ – Sunnyskyguy EE75 Dec 29 '17 at 18:06
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    \$\begingroup\$ That's quite the shopping list of requirements to do at home. Your best bet is probably a photographic process with plating of some sort. But way too specialised for me to comment much further than that. \$\endgroup\$ – Trevor_G Dec 29 '17 at 18:17
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    \$\begingroup\$ Sorry Trevor, images like this merge into a solid color at lower resolution or as a thumbnail. Had to be done \$\endgroup\$ – Mark Legault Dec 29 '17 at 18:29
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You can buy glass with Indium-Tin-Oxide coating and etch it with 55% HCL at room temperature. The Adafruit item is out of stock, but it should be possible to find other suppliers. Thickness of the ITO is 1850Å.

Etch rate is approximately 25Å (2.5nm) /second. Good results were reported using AZ 1350H photoresist. Total etch time would be less than 1.5 minutes.

You would need something like film and a vacuum exposure setup to get good resolution and exposure.

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  • \$\begingroup\$ any ideas if it will work with ITO coated PET though? \$\endgroup\$ – Mark Legault Dec 30 '17 at 0:47
  • \$\begingroup\$ Maybe. PET compatibility with 10% HCL is listed as "good", but "poor" against concentrated HCL. roboworld.com/wp-content/uploads/2017/08/… \$\endgroup\$ – Spehro Pefhany Dec 30 '17 at 2:49
  • \$\begingroup\$ As long as ITO can be etched with 10% HCL \$\endgroup\$ – Mark Legault Dec 30 '17 at 7:29
  • \$\begingroup\$ @MarkLegault It might withstand more concentrated acid for the very short exposure time- a minute or two of etch time- or even the 10% acid might affect the transparency, especially if it has to sit for 20 or 30 minutes. Easy enough to try, except for the hazmat shipping charges on acid. Retail hardware store muriatic acid is of reasonable intermediate strength but AFAIUI it may be more aggressive as it is not pure. \$\endgroup\$ – Spehro Pefhany Dec 30 '17 at 8:17
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    \$\begingroup\$ chemistry.stackexchange.com/questions/88071/… \$\endgroup\$ – Mark Legault Dec 30 '17 at 15:53

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