Journal
COLLOID AND POLYMER SCIENCE
Volume 289, Issue 11, Pages 1283-1294Publisher
SPRINGER
DOI: 10.1007/s00396-011-2450-8
Keywords
Nanocluster; Polystyrene; Lithography
Categories
Funding
- National Nano Device Laboratory
Ask authors/readers for more resources
In this study, we formed grafted polystyrene (PS) brushes possessing nanocluster structures through atom transfer radical polymerization from initiator cores presented on Si surfaces that had been generated using reactive ion etching (RIE). We established the surface grafting polymerization kinetics of the nanoclustered PS chains on the Si surfaces to fit their experimentally determined thickness (ellipsometry) and number-average molecular weight (M-n) of free PS (gel permeation chromatography). The propagation rate (k(p)) and active grafting species deactivation rate (k(d)) were obtained from reactions involving styrene concentrations from 0.2 to 2 M. We also used scanning electron microscopy to observe the morphologies of the PS grafted to the surfaces after various reaction times at various styrene concentrations. The PS brushes grafted onto the Si surfaces under styrene concentrations of 0.2, 0.5, 1, and 2 M exhibited clustered structures having cluster diameters of 12, 28, 42, and 45 nm, respectively; from these observations, we calculated the critical grafting density. In addition, we generated highly dense, well-defined patterns of PS on patterned Si(100) surfaces through the use of a very-large-scale integration process involving electron beam lithography and RIE. We employed the RIE system to generate a high density of reactive species at the bottom of the trenches for graft polymerization. After 21 h of grafting, AFM imaging revealed dense line patterns of nanoclustered PS.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available