Fig. 3.

SEM images of a double layer polyester device with a height of 300 µm in (a) oblique view and in (b) top view and of a single layer polyester device with a height of 178 µmin top view (c), at 100× and 500× magnification. (d) SEM profile of double layer deep wells. (e) Relationship between designed and measured eccentricity of round features, when engraved into polyester sheets. (f) Profilometer measurements of a range of well designs, indicating the conical well profile. (g) Schematic representation of taper effects by laser ablation onto single and double polyester layers (α is the taper angle) and plot of taper angle vs. laser write speed. All scale bars are 150 µm.