Embossing stamp for optically diffuse micro-channel

1. An embossing stamp, comprising:

a stamp substrate having a planar surface;

two or more stamp structures formed on the stamp substrate having stamp surfaces extending from the stamp substrate to emboss a micro-channel in a layer, wherein at least one of the stamp surfaces forming the micro-channel is non-planar and incident-light-diffusive;

portions of the embossing stamp between the stamp structures, wherein all of the portions have only flat and incident-light-non-diffusive surfaces; and

wherein the stamp surfaces include one or more stamp side surfaces intersecting the stamp substrate and a stamp bottom surface intersecting a stamp side surface and not the stamp substrate.

2. The embossing stamp of claim 1 , wherein stamp structures closer to the stamp substrate are wider than stamp structures farther from the stamp substrate.

3. The embossing stamp of claim 1 , wherein two or more of the stamp surfaces have surface normals that are not parallel.

4. The embossing stamp of claim 1 , wherein two or more of the stamp surfaces have surface normals that are parallel.

5. The embossing stamp of claim 1 , wherein one or more of the stamp surfaces is at least partially curved.

6. The embossing stamp of claim 1 , wherein one or more of the stamp surfaces is irregular.

7. The embossing stamp of claim 1 , wherein the incident-light-diffusive surface has planar portions that have a dimension less than or equal to 100 microns.

8. The embossing stamp of claim 1 , wherein only the stamp bottom surface is non-planar.

9. The embossing stamp of claim 1 , wherein only the stamp bottom surface is incident-light diffusive.

10. The embossing stamp of claim 1 , wherein at least a portion of the stamp bottom surface is at least as far from the stamp substrate as at least one of the stamp side surfaces.

11. The embossing stamp of claim 1 , wherein stamp side surfaces extend a common distance from the stamp substrate.

12. A method of making an embossing stamp, comprising:

providing a material; and

forming the material into an embossing stamp having a stamp substrate and one or more stamp structures, the one or more stamp structures having stamp surfaces extending from the stamp substrate, wherein at least one of the stamp surfaces is non-planar; one or more portions of the embossing stamp between the stamp structures, wherein the one or more portions are flat and incident-light-non-diffusive; and wherein the stamp surfaces include one or more stamp side surfaces intersecting the stamp substrate and a stamp bottom surface intersecting a stamp side surface and not the stamp substrate; and wherein one or more of the stamp surfaces is an incident-light-diffusive surface.

13. The method of claim 12 , wherein stamp structures closer to the stamp substrate are at least as wide or wider than stamp structures farther from the stamp substrate.

14. The method of claim 12 , further including:

first forming the material into an embossing stamp having a stamp substrate and stamp structures, the stamp structures having stamp surfaces extending from the stamp substrate, wherein the stamp surfaces are planar; and

second treating one or more stamp surfaces to render one or more stamp surfaces non-planar.

15. The method of claim 14 , wherein treating the one or more stamp surfaces includes mechanically abrading the one or more stamp surfaces.

16. The method of claim 14 , wherein treating the one or more stamp surfaces includes plasma treating the one or more stamp surfaces.

17. The method of claim 14 , wherein treating the one or more stamp surfaces includes exposing the one or more stamp surface to a corona discharge.

18. The method of claim 14 , wherein forming the embossing stamp further includes:

providing a liquid material in the mold; and

curing the liquid material.

19. The method of claim 14 , wherein forming the embossing stamp further includes providing a mold having one or more mold surfaces at least one of which is non-planar.