Fabrication of Nano/Microstructured Organic Films using Breath Figures: Mohan Srinivasarao * Process:
Polymer (0.1~5 wt%) in highly volatile solvent
Moist airflow
PS in CS2
Temperature (oC)
* Effect of Solvent Choice and Air Flow Speed: Solution surface temperature change and supersaturation Parameters: ¾ Mass Diffusivity ¾ Thermal Diffusivity ¾ Specific Heat ¾ Heat Conductivity ¾ Vapor Pressure ¾ Density
CHCl3
C6H6 CS2 Theoretical Time (sec)
* Microstructured Films with Different Polymers, Solvents, Substrates, and Temperature History: 40 μm
PS in CS2
40 μm
PS in Benzene
20 μm
Azide-PPE in CS2
Porous PS*1 or azide-PPE*2 on a glass substrate *1 PS = polystyrene, *2 PPE = poly[p-(phenylene)ethynylene]
20 μm
PS in CS2 on Si PS on Si wafer
15.2 × 15.2 × 4.7 (µm) As made
10.8 × 10.8 × 2.2 (µm) After heating
Azide-PPE on glass
