Fig. 2.

Illustration of processing steps for spin coating used to synthesize the multilayered thin films. Step 1: A Pyrex glass is used as a substrate and is coated with Silane to allow easy removal of the cured PDMS. Step 2: The mixture which contains PDMS, TiO₂, and curing agent is dropped on the substrate. Steps 3 and 4: The mixture is spun for 5 min depended upon the rotational speed of each layer. Step 5: After the end of spin coating, the PDMS mixture is placed on a hot plate at 150°C for 1 h to cure it.