Implosion nanofabrication
Implosion fabrication is a manufacturing method that allows for very small
(but not yet atomically precise) electric leads down to the low single digit nanometer scale
without the need for hard to access and/or very expensive silicon chip production lab.
While there are processes for making such small leads on silicon these are at the cutting edge (2022) and only accessible
for one-off masks for processors produced in high quantities and very expensive.
More accessible fabrication labs are still expensive (how expensive?) and much lower resolution.
Detailed summary
Below is a bullet-pointed summary from the paper:
"3D nanofabrication by volumetric deposition and controlled shrinkage of patterned scaffolds"
http://science.sciencemag.org/content/362/6420/1281
Process:
- starting out with acrylate hydrogel base (x10 or x20 cross-linked)
- infusion with functionalized fluorescin
- two photon excitation links fluorescin to hydrogel (at a second site beside the functionalised one)
- "patterning": the functionalized fluorescing is linked voxel by voxel (via reverse operated optical microscope?)
(quite strong) anisotropic distortion can be accounted for (it's repeatable) - "removal": remaining fluorescin is washed out
- repetition with differently functionalized fluorescin is possible, but contamination of the former one about 20%
- depositing materials on the patterned active groups (via conjugation chemistries)
- "intensification": depositing more where there already is some of the same
- (in case of metals like silver: chelate excess metal to suppress conductivity at undesired places)
- "shrinking": contracting hydrogel by adding hydrochloric acid or MgCl2 (only former allows next step)
- "shrinking further": by dehydration
- in case of metals like silver: "sintering": by repeating the optical patterning in case of deposited silver
Limits:
- not atomically precise (surface roughness comes near, but no control over individual atoms)
- not atomically accurate
- no hollow voids, scaffold remains in final product
- product not resilient to water
- still relatively experimental (technology readiness level?)
Capabilities:
- shrunken voxels ~50nm
- discontinuous conductors with high conductivity
- no overhang limitations (no layer by layer deposition involved, layer by layer exposure possible)
- Many materials possible: metals, semiconductors, and biomolecules
- in particular: highly conductive, 3D silver nanostructures within an acrylic scaffold (the dried hydrogel)
- big maximal build volume (what exactly effectively after full shrinking?)
- already very fast and can be made even faster
