Title | Laser-induced nanoscale thermocapillary flow for purification of aligned arrays of single-walled carbon nanotubes. |
Publication Type | Journal Article |
Year of Publication | 2014 |
Authors | Du F, Felts JR, Xie X, Song J, Li Y, Rosenberger MR, Islam AE, Jin SHun, Dunham SN, Zhang C, Wilson WL, Huang Y, King WP, Rogers JA |
Journal | ACS Nano |
Volume | 8 |
Issue | 12 |
Pagination | 12641-9 |
Date Published | 2014 Dec 23 |
ISSN | 1936-086X |
Abstract | Although aligned arrays of single-walled carbon nanotubes (SWNTs) have outstanding potential for use in broad classes of advanced semiconductor devices, the relatively large population of metallic SWNTs (m-SWNTs) that results from conventional growth techniques leads to significantly degraded performance. Recently reported methods based on thermocapillary effects that enable removal of m-SWNTs from such arrays offer exceptional levels of efficiency, but the procedures are cumbersome and require multiple processing steps. Here we present a simple, robust alternative that yields pristine arrays of purely semiconducting SWNTs (s-SWNTs) by use of irradiation with an infrared laser. Selective absorption by m-SWNTs coated with a thin organic film initiates nanoscale thermocapillary flows that lead to exposure only of the m-SWNTs. Reactive ion etching eliminates the m-SWNTs without damaging the s-SWNTs; removal of the film completes the purification. Systematic experimental studies and computational modeling of the thermal physics illuminates the essential aspects of this process. Demonstrations include use of arrays of s-SWNTs formed in this manner as semiconducting channel materials in statistically relevant numbers of transistors to achieve both high mobilities (>900 cm2 V(-1) s(-1)) and switching ratios (>10(4)). Statistical analysis indicates that the arrays contain at least 99.8% s-SWNTs and likely significantly higher. |
DOI | 10.1021/nn505566r |
Alternate Journal | ACS Nano |
PubMed ID | 25495504 |
Related Institute:
Dalio Institute of Cardiovascular Imaging (Dalio ICI)