Dry adhesives and methods for making dry adhesives

A method of forming a dry adhesive fiber array in a first structure including an etch layer and a barrier layer, wherein the etch layer and the barrier layer are adjacent to each other and are made from different materials, wherein the etch layer includes a surface of the etch layer opposite the barrier layer, comprising:

• forming a plurality of openings through the etch layer [[and ]]to the barrier layer;
• filling openings of the plurality of openings with a material;
• removing the barrier layer from the material in the openings of the plurality of openings;
• and
• removing the etch layer from the material in the openings of the plurality of openings.

A method of forming a dry adhesive multi-layer fiber arrays with a first structure including a first etch layer and a first barrier layer, wherein the first etch layer and the first barrier layer are adjacent to each other and are made from different materials, wherein the first etch layer includes a first surface of the first etch layer opposite the first barrier layer, and a second structure including a second etch layer and a second barrier layer, wherein the second etch layer and the second barrier layer are adjacent to each other and are made from different materials, wherein the second etch layer includes a second surface of the second etch layer opposite the second barrier layer, comprising the steps of:

• forming a first plurality of openings through the first etch layer to the first barrier layer of the first structure;
• forming a second plurality of openings through the second etch layer to the second barrier layer of the second structure, wherein a cross-section of at least one opening of the second plurality of openings is smaller than a cross-section of the at least one opening of the first plurality of openings;
• connecting the first structure to the second structure such that at least one opening of the second plurality of openings corresponds to at least one opening of the first plurality of openings;
• removing the first barrier layer from the first etch layer;
• filling the first and second plurality of openings with a material;
• removing the second barrier layer from the second etch layer;
• and removing the first and second etch layers surrounding the material in the openings of the first and second plurality of openings to form the dry adhesive multi-layer fiber arrays.