Seamless covalent cleaving
Mechanosynthesis faces the problem that one needs to build onto something as support.
One can't start free floating in a vacuum,
one can't build off a free floating gas molecule that is not bond to anything.
But also the mechanosynthesized parts
- are supposed to be not covalently connected in the final assembly or
- are supposed to get covalently connected to a different place via seamless covalent welding avoiding limitations of in place mechanosynthesis
The idea is to mechanosynthesize direct onto the same material (diamond onto diamond, silicon onto silicon, and such)
Thus incurring no lattice mismatch issues and being able to use just the build skills fro this one material.
but to make an acute angle concave notch at the base where the crystolecule product part meets the flat build plate
So then the part is finished an applied large sidewards force can break the part off in a very predictable way
In a way that ideally does not damage the build-plate and crystolecule product by atoms ending up on the wrong side.
Cleaveoff and product part in-machine-phase-retention (= preventing shoot-off)
When breaking off the product crystolecule part then
one needs to leave some angular freedom but still apply full form closure
as vdW forces will not be sufficient to prevent the crystolecule from shooting off ballistically
to the next nearest random surface that might be a far away place and surely will be an unknown place.
Escape of machine phase.
Heck in macroscale UHV volume as in today's UHV systems
one may even get a relative to nanoscale huge gravitation parabola as trajectory
before it hitting a wall never to be found again.
Post treatment of cleaved surfaces
The cleaved surfaces end up depassivated and they can
★ either be passivated with some further mechanosysthesis
★ or be left as is for later seamless covalent welding off site at some other place
… possibly still forming bulk-detached parts but bigger parts. Pairwise combination or bigger.
If there is some damage (some atoms ended up on the wrong side) then post treatment can do the need repair on both sides but for more advanced systems this would be highly undesirable as this prevents factory assembly line style open loop control in highly optimized advanced gem-gum factories.
If wildly different breaks happen then the geometry needs to be changed.
Or more angular freedom in the break-off needs to be given.