High-Throughput Study of Surface Pattern Formation in Thin Diblock Copolymer Films
Abstract
Surface pattern formation in diblock copolymer films is investigated as a function of film thickness h and molecular mass M using a high-throughput approach involving gradients of h. Smooth films are observed for extended ranges of h centered about integral multiples of the lamellar thickness L_o, and this effect is attributed to an increase in the surface chain density with increasing h in the outer brush-like copolymer layer. Stable labyrinthine surface patterns resembling spinodal patterns are also observed for other h ranges and the average size λ of these patterns is found to scale as, λ L_o-2.5 M^ -1.5. Hole and island surface patterns occur for h ranges between those of the labyrinthine patterns and the smooth regions and their size is found to similarly decreases with increasing M. The magnitude of the film thickness gradient is found to influence the relative width of the features such that the smooth regions occupy an increasing fraction of the film surface area with increasing film gradient.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2001
- Bibcode:
- 2001APS..MAR.W7001S