150
8 Nanofabrication on Reactive Block Copolymer Film …
show similar defined patterns. Following hydrolysis and NHS activation, the PtBA
islands can be used to covalently immobilize amino-functionalized molecules.
The changes in the film surface composition induced by the treatment were already
reported in Chap. 3. Based on evidence from XPS and contact angle measurements
with diiodomethane as a probe liquid, PS and PtBA were concluded to co-exist on
the film surface [15].
The morphology of the polymer films was further investigated with intermittent
contact mode atomic force microscopy (AFM), as shown in Fig. 8.2. After annealing
PS 690 -b-PtBA 1210 film at 130 °C, a microphase-separated film was observed with inplane cylindrical structures (Fig. 8.2a, b). The equilibrium domain spacing calculated
based on the AFM data was 80 ± 5 nm. After the cyclohexane solvent treatment,
the surface morphology was characterized by an irregular pattern of protrusions
(Fig. 8.2c, d), which had typical heights of ~4 nm, diameters of 50 ± 5 nm, and a
mean separation distance of 80 ± 5 nm.
The surface area covered by the phase with bright phase contrast in the AFM
images (χ ~ 0.55) showed a clear correspondence with the surface composition
Fig. 8.2 Tapping mode AFM images of spin-coated PS 690 -b-PtBA 1210 films: a Height and b phase
images acquired for polymer films after annealing in vacuum at 130 °C; c Height and d phase
images acquired for polymer films after cyclohexane treatment and drying
8 Nanofabrication on Reactive Block Copolymer Film …
show similar defined patterns. Following hydrolysis and NHS activation, the PtBA
islands can be used to covalently immobilize amino-functionalized molecules.
The changes in the film surface composition induced by the treatment were already
reported in Chap. 3. Based on evidence from XPS and contact angle measurements
with diiodomethane as a probe liquid, PS and PtBA were concluded to co-exist on
the film surface [15].
The morphology of the polymer films was further investigated with intermittent
contact mode atomic force microscopy (AFM), as shown in Fig. 8.2. After annealing
PS 690 -b-PtBA 1210 film at 130 °C, a microphase-separated film was observed with inplane cylindrical structures (Fig. 8.2a, b). The equilibrium domain spacing calculated
based on the AFM data was 80 ± 5 nm. After the cyclohexane solvent treatment,
the surface morphology was characterized by an irregular pattern of protrusions
(Fig. 8.2c, d), which had typical heights of ~4 nm, diameters of 50 ± 5 nm, and a
mean separation distance of 80 ± 5 nm.
The surface area covered by the phase with bright phase contrast in the AFM
images (χ ~ 0.55) showed a clear correspondence with the surface composition
Fig. 8.2 Tapping mode AFM images of spin-coated PS 690 -b-PtBA 1210 films: a Height and b phase
images acquired for polymer films after annealing in vacuum at 130 °C; c Height and d phase
images acquired for polymer films after cyclohexane treatment and drying