Multilevel structured surfaces

1. An apparatus comprising:

a substrate having a surface with electrically connected and electrically isolated fluid-support structures thereon, wherein

each of said fluid-support-structures have at least one dimension of about 1 millimeter or less,

said electrically connected fluid-support-structures are taller than said electrically isolated fluid-support-structures, and

a difference between a height of said electrically connected fluid-support-structures and a height of said electrically isolated fluid-support-structures is sufficient to prevent a fluid locatable on said electrically connected fluid-support-structures from contacting said electrically isolated fluid-support-structures.

2. The apparatus of claim 1 , wherein a height of said electrically isolated fluid-support-structures is sufficient to prevent a fluid locatable on said electrically isolated fluid-support-structures from contacting a base layer of said substrate.

3. The apparatus of claim 1 , wherein a height of said electrically connected fluid-support-structures is at least about 5 microns greater than a height said electrically isolated fluid-support-structures, said height of said electrically isolated fluid-support-structures is at least about 2 microns, and a lateral separation between adjacent ones of said electrically isolated fluid-support-structures is less than about 3 microns.

4. The apparatus of claim 1 , wherein a lateral separation between adjacent ones of said electrically connected fluid-support-structures ranges from about 1 to about 20 microns.

5. The apparatus of claim 1 , wherein a density of said electrically isolated fluid-support-structures within at least one region of said surface is greater than a density of said electrically connected fluid-support-structures in said region.

6. The apparatus of claim 5 , wherein said density of said electrically isolated fluid-support-structures ranges from about 2 to about 10 times greater than said density of said electrically connected fluid-support-structures.

7. The apparatus of claim 1 , wherein said electrically isolated fluid-support-structures are interspersed between said electrically connected fluid-support-structures.

8. The apparatus of claim 1 , wherein each of said fluid-support-structures comprises a post and said one dimension is a lateral thickness of said post.

9. The apparatus of claim 1 , wherein each of said fluid-support-structures comprises a cell and said at least one dimension is a lateral thickness of a wall of said cell.

10. The apparatus of claim 1 , further comprising an electrical source that is electrically coupled to said electrically connected fluid-support-structures, said electrical source configured to apply a voltage between said electrically connected fluid-support-structures and a fluid locatable on said surface.

11. A method comprising,

reversibly moving a fluid locatable on a substrate surface, comprising:

placing said fluid on said substrate surface, said surface comprising electrically connected and electrically isolated fluid-support-structures thereon, wherein

each of said fluid-support-structures have at least one dimension of about 1millimeter or less,

said electrically connected fluid-support-structures are taller than said electrically isolated fluid-support-structures, and

said fluid lies on tops of said electrically connected fluid-support-structures;

applying a voltage between said fluid and said electrically connected fluid-support-structures thereby causing said fluid to lie on tops of said electrically isolated fluid-support-structures; and

removing said voltage thereby causing said fluid to lie on said tops of said electrically connected fluid-support-structures.

12. The method of claim 11 , wherein a temperature of said surface remains substantially constant during said moving.

13. A method, comprising:

forming a plurality of electrically isolated fluid-support-structures on a surface of a substrate; and

forming a plurality of electrically connected fluid-support-structures on said surface, wherein

each of said fluid-support-structures have at least one dimension of about 1 millimeter or less,

said electrically connected fluid-support-structures are taller than said electrically isolated fluid-support-structures, and

a difference between a height of said electrically connected fluid-support-structures and a height of said electrically isolated fluid-support-structures is sufficient to prevent a fluid locatable on said electrically connected fluid-support-structures from contacting said electrically isolated fluid-support-structures.

14. The method of claim 13 , wherein forming said plurality of electrically isolated fluid-support-structures comprises depositing an electrically insulating layer over said surface and patterning said electrically insulating layer.

15. The method of claim 14 , wherein said patterning comprises removing portions of said electrically insulating layer that do not define said electrically isolated fluid-support-structures.

16. The method of claim 13 , wherein forming said plurality of electrically connected fluid-support-structures comprises forming an electrically conductive layer over said surface and patterning said electrically conductive layer.

17. The method of claim 16 , wherein said electrically conductive layer is formed over said electrically isolated fluid-support-structures.

18. The method of claim 16 , wherein said patterning comprises removing portions of said electrically conductive layer that do not define said electrically conductive fluid-support-structures.

19. The method of claim 16 , further comprising forming an electrically insulating coating over said electrically connected fluid-support-structures.