Abstract: Methods and apparatus for positioning a structure on a polymer layer are described. A method may involve forming a first polymer layer. The method may further involve positioning, by an apparatus, a structure on the first polymer layer, where the apparatus comprises a rod having a first end that supports the structure as the structure is being positioned and a plunger located around the first end of the rod that presses the structure onto the first polymer layer as the structure is being positioned. And the method may involve forming a second polymer layer over the first polymer layer and the structure, where the first polymer layer defines a first side of a body-mountable device and the second polymer layer defines a second side of the body-mountable device opposite the first side.