[moved here] - some ideas about micro/nano-fabrication and such ...

The project has recently woken up with the μRepRap (RepRapMicron). The idea being to make tiny things with micron or sub-micron resolution. Ultimately, this includes very tiny RepRaps. Progress on [blog.reprap.org]

Vik ;v)

Edited 1 time(s). Last edit at 05/02/2024 10:44AM by VDX.

I plan on going down to the micron level. Everyone wants to use lasers but they're not easy to get in many countries and don't work well once you get down to the micron level. I'm hoping my hardware will scale down even smaller eventually, heading for the nanometre. That's going to be a world of fun because at that scale air molecules are charging around like cannonballs!

... for some decent "microfabrication" in sort of a DIY approach you can use lasers with a fine spot - common fiberlasers have spot diameters around 30 microns, with different optics even down to below 10 microns.

Here I was testing with "laser assisted thermo-transfer" of previously applied spray paint with a fiber laser (30 micron spot) and a blue laser-diode (80 micron spot) - in the videos with only a single layer of maybe 10 microns resulting height ... with "stacking" more layers you can build any wished height or even change the material per layer ... or, when changing the carriers for the sme layer, with different materials in the same layer too, as it can be "transferred" without overlapping:

[www.youtube.com]

[www.youtube.com]

[www.youtube.com]

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

... with the "laser-thermo-transfer" some nanometer thick layers can be "sprayed" or more like "PVD" coated (as in Physical Vapor Deposition) - the lower limit are actually the spot sizes of down to 50 microns with laser diodes or down to 10 microns with fiber-lasers and such (have some UV-DPSS and actually an "green" picosecond laser for testing until end of May).

What would help with finer lateral details would be photo-masks ... or maybe some sort of DIY electron beam gears in vacuum ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I've looked at a system using sheets of chip substrate mask. Worked quite well and I considered using it for RepRapMicron. However, the materials and preparation were too much for the average RepRap maker, expensive, and hard to get hold of.

Also, one development advantage of the probe approach is that you have the basis for a tool that can pick and place. It's all very well making micron-sized objects, but you have to be able to handle them as well!

Vik :v)

... from 1999 to 2006 I was busy with R&D for micro/nano-tech and too handling them (microscopy, micro/nano-positioning, micro-assembly, ...).

If you'll need some help here -- have some of the parts and more in my basement (microscopes, grippers/tweezers, micro-positioning stages, ...)

Here some related images:






Edited 1 time(s). Last edit at 05/02/2024 06:47AM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

How did you make your probe points? I'm just electro-eroding wire with salt water and batteries. Works fine.

Vik :v)

... I had a cooperation (more I had to help them solve some handling issues), from where I've got a bunch of "nano-nailheads" -- it's essentially a halfsphere of gold or platinum with 30µm diameter with a 30 or 50µm long "nano-needle" centered at the flat side.

This nano-needles were around 100 nanometers at the center-point connection and some nanometers at the tip - they were made galvanically by "growing" the metal through "nano-bores", made by shooting accelerated ions through the polymer sheets and then etch/dissolve the below 1 nanometer wide through-hole to the desired diameter (either 100nm straight, or conical from 10nm to 100nm) ... and last let grow the metal through the bores until the "half-spheres" are formed.

As they were embedded in the polymer-sheet with the half-sphere on top and the nano-needle embedded in the sheet, "arming" them was pretty easy by "wetting" a bigger needle tip with some solder, touch the half-sphere with the tinned tip, then heat the connection point with a laser pulse ... and then simply pull the tip out, so the "nano-tip" is breaking free and can be used as probe point.

This super small gold (or platinum) nano-needles were meant for measuring the voltage potentials in living cells.


Here some optical and REM images of the prepared "nano-nailheads" (the half-sphere "heads" with the nano-needles still embedded in the polymer sheet):








And here images from the first Test of "solder-arming" them with a pretty "big" tin-coated needle-tip (the later were much, much smaller):





If you look into the last image, you can see some "shadows" of the nano-needles especially at the topmost left gold body, pointing to top-left

Edited 2 time(s). Last edit at 05/02/2024 05:52PM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

... by the way - with the galvanic approach you can easy manufacture any size and form of tips and probe-points, which you can get as "hollow form" in a plastic sheet.

This would be a perfect use for the UV-LCD-3D-printers with roughly 25 microns big "voxels".

With some tweaking you can get even finer resolution, if you modify a common data-beamer with an UV-LED as light source and adding a reducing lens in front of the optics.


*** EDIT *** - on the second thought -- I have some image transferring "glassfibers" (=fiber-bundles) with 0.2mm diameter and 3000 single fibers and some thicker too, with 10.000 or 30.000 single fibers in the bundle.

The single fibers have a diameter of around 3 microns - so, when focussing an UV-light-image on one end, this "image" will emit from the other end - so it could be used as a "light-stamp" with 3 micron UV-light pixels in a hexagonal arrangement ... would be nice, to "write" some UV-light patterns on a film to use in some sort of (coarse) electronics-DIY ... or micro-etching mechanical parts ... or something different too

Edited 1 time(s). Last edit at 05/02/2024 06:15PM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

... and for "micro/nano-positioning" -- if you look in my first attached image - on the left, above "Positionierer" - this is a 3-axis nano-positioner, assembled from 3 "Piezolegs"-drives.

This setup has a moving/positioning range of 23x23x23mm in XYZ with an overall accuracy of 150 nanometer per "step" or, when in "clamped" mode, even down to sub-nanometer resolution ... what it lacks in this version, is some sort of linear measuring the position for closed-loop ... so it could develop misposition, if the load is not symmetrical or too high ...

Edited 1 time(s). Last edit at 05/03/2024 07:03AM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

What is the use case for this for joe average?

... it's not really meant for Joe average -- more for interested individuals or R&D groups ... either comercial or DIY/OSHW

Edited 1 time(s). Last edit at 05/03/2024 02:54PM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]