Patent ID: 8287808

Claim:
An apparatus, comprising: a plurality of closed-cells on a substrate surface, each of said closed cells having external walls that enclose an open interior area on all sides except for the side over which a liquid could be disposed, while being in contact with top surfaces of one or more of said walls, and wherein: each of said closed-cells comprise one or more internal walls that divide said interior area of each of said closed-cells into a single centrally located first zone and a plurality of second zones that define said central first zone, said first zone occupies a larger portion of said interior area of said closed-cell than any one of said second zones, said first and second zones are interconnected to form a common volume among said first zone and said plurality of said second zones of said closed cell, said plurality of second zones are located proximate to said external walls of said closed-cell and, said first zone occupies a portion of the interior area that is at least about two times larger than said interior area occupied by any one of said second zones.