| AVS 60th International Symposium and Exhibition | |
| Thin Film | Tuesday Sessions |
| Session TF-TuM |
| Session: | ALD for Emerging Applications |
| Presenter: | B. Kalanyan, North Carolina State University |
| Authors: | B. Kalanyan, North Carolina State University C.J. Oldham, North Carolina State University W.J. Sweet III, North Carolina State University G.N. Parsons, North Carolina State University |
| Correspondent: | Click to Email |
Low temperature tungsten atomic layer deposition (ALD) using WF6 and dilute silane (SiH4, 2% in Ar) can yield highly conductive coatings on nylon-6 microfiber mats. Coated nonwoven mats are flexible and supple with conductivity of ~1,000 S/cm. We find that an alumina nucleation layer, reactant exposure, and deposition temperature all influence the rate of W mass uptake on 3D fibers. Transmission electron microscopy (TEM) reveals highly conformal tungsten coatings on nylon fibers with complex ‘winged’ cross-section. We calibrate tungsten growth rate on nylon-6 by imaging film thickness on high surface area anodic aluminum oxide. Using reactant gas ‘hold’ sequences during the ALD process, we conclude that reactant species can transport readily to reactive sites throughout the fiber mat, consistent with conformal uniform coverage observed by TEM. The conductivity of 1,000 S/cm for the W-coated nylon is much larger than found in other conductive nonwovens. W-coated nylon mats maintain 90% of their conductivity after being flexed around cylinders with radii as small as 0.3 cm. Metal ALD coatings on nonwovens make possible the solvent-free functionalization of textiles for electronic applications.