Nanofabrication using heated probe tips

We present progress towards scalable, high precision nanofabrication in a variety of materials using heated Atomic Force Microscope (AFM) probes. Temperature control of a heated AFM tip allows nanometer scale thermochemical patterning, deposition of thermoplastic polymers, and surface melting. The challenges that must be overcome to scale such a technology to industrial-scale manufacturing include tip wear, thermal and mechanical control of the cantilever, chemical reaction control at the tip-surface interface, and fabrication throughput. To mitigate tip wear, we have integrated nanocrystalline diamond films onto our heated AFM probe tip. Such diamond tips are extremely resistant to wear and fouling at a self-heating temperature of 400 C and load force of 200 nN over long distances. To improve cantilever temperature control, a closed loop feedback control was designed to allow for 0.2 C precision temperature control during nanolithography. Electrohydrodynamic jetting controls the deposition of polyethylene onto a heated probe tip. Finally, to address throughput, we have fabricated cantilever arrays having independent temperature control and integrated them into a commercial AFM system. We show these advances by patterning thousands of nanostructures of polyethylene and poly(3-dodecylthiophene), with cumulative length more than 2 mm and patterning accuracy better than 50 nm.