 | « on: April 05, 2007, 08:53:03 PM » |
Every 4 microns or so, a CNT sidewall defect exists. If some of these defects could be "fixed", an SE ribbon material will surely be around the corner.
The key is to make the repair process cheap. This rules out mechanical repair (using an SPM for instance) over Liftport's calender. To detect the defect co-ordinates, the easiest method I can think of is to have a spun CNT thread zoom by an automated Electron Microscope capable of telling little hexagons and pentagons apart.
Defects change the electrical properties of a CNT so it would be even easier to send electricity through the CNT, provided someone can figure out how to integrate arbitrary sections of an intact CNT into a circuit.
Once detected, hit the defect with an appropriately energetic photon. I don't know the energy required to turn a pentagon and heptagon on a CNT surface into two hexagons (maybe between 2eV-8eV), or if photons can even be fired to hit an Angstrom-sized target. But every other non-mechanical healing method I can think of targets non-defect sites as well, and so *I think* creates more new defect sites than healed.
The photon has to hit the defect site and not hexagons, else *I think* new defect sites would be created. This would require "CNT feed" tolerances sub-Angstrom; that is, the timing between E-beam scan and photon emission (IDK if it is easier to run the beams by the CNT or vice-versa) must be short enough to avoid "losing" the defect co-ordinate. I don't think you can digitally store the defect sites and heal them later. I think the CNT will naturally twist and "slip" whatever Electron Beam co-ordinate mapping system exists.
I'm envisioning an E-Beam Microscope and a very closely attached "hula hoop" of tuned lasers. The CNT spun first through the Microscope and than the ring of lasers.
There are few scientific papers directly about CNT defect repair (two I count) but it doesn't take too much widening of the field to be inundated with CNT papers. Over the months ahead I'll try to sift through (free pre-print) papers that might be relavent to the defect healing methodology described above and post them here or on the ribbon thread. Or I'll revise my little CNT repair factory.
The key is to make the repair process cheap. This rules out mechanical repair (using an SPM for instance) over Liftport's calender. To detect the defect co-ordinates, the easiest method I can think of is to have a spun CNT thread zoom by an automated Electron Microscope capable of telling little hexagons and pentagons apart.
Defects change the electrical properties of a CNT so it would be even easier to send electricity through the CNT, provided someone can figure out how to integrate arbitrary sections of an intact CNT into a circuit.
Once detected, hit the defect with an appropriately energetic photon. I don't know the energy required to turn a pentagon and heptagon on a CNT surface into two hexagons (maybe between 2eV-8eV), or if photons can even be fired to hit an Angstrom-sized target. But every other non-mechanical healing method I can think of targets non-defect sites as well, and so *I think* creates more new defect sites than healed.
The photon has to hit the defect site and not hexagons, else *I think* new defect sites would be created. This would require "CNT feed" tolerances sub-Angstrom; that is, the timing between E-beam scan and photon emission (IDK if it is easier to run the beams by the CNT or vice-versa) must be short enough to avoid "losing" the defect co-ordinate. I don't think you can digitally store the defect sites and heal them later. I think the CNT will naturally twist and "slip" whatever Electron Beam co-ordinate mapping system exists.
I'm envisioning an E-Beam Microscope and a very closely attached "hula hoop" of tuned lasers. The CNT spun first through the Microscope and than the ring of lasers.
There are few scientific papers directly about CNT defect repair (two I count) but it doesn't take too much widening of the field to be inundated with CNT papers. Over the months ahead I'll try to sift through (free pre-print) papers that might be relavent to the defect healing methodology described above and post them here or on the ribbon thread. Or I'll revise my little CNT repair factory.
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