Methods and system for mass production, volume manufacturing of re-entrant structures

A system for mass production, volume manufacturing of reentrant structures, the system comprising:

• a first and second rollers disposed with a gap between them;
• the gap dimensioned to surround an array of non-curable thermoplastic pillars protruding from a substrate and the substrate;
• relative rotation of the first and second rollers_being configured to draw the array and the substrate through the_gap;
• at least one temperature adjusting component configured to_provide a temperature gradient from a surface of the non-curable thermoplastic pillars disposed farthest away from the substrate to a surface of the substrate;
• a temperature at the surface of the non-curable thermoplastic pillars disposed farthest away from the substrate being the temperature at which_a non-curable thermoplastic material of the non-curable thermoplastic pillars is substantially malleable;
• the temperature gradient being provided by heating a roller from the_first and second rollers, the roller being in contact with the surface of the non-curable thermoplastic pillars disposed farthest away from the substrate, to a first temperature while maintaining another roller from the first and second rollers, the another roller being in contact with the substrate, at a second temperature;
• a ratio between the first temperature and the second temperature being selected such that nonuniform flow_is produced in the non-curable thermoplastic material;
• at least one pressure adjusting component configured to apply pressure on the surface of the non-curable thermoplastic_pillars disposed farthest away from the substrate;
• the pressure_and the temperature at the surface of the non-curable thermoplastic pillars disposed farthest away from the substrate selected to cause irreversible deformation of the non-curable_thermoplastic material;
• whereby the re-entrant structure is formed;
• a driver component configured to drive rotation of the_first and second rollers;
• and
• a system controller configured to control the driver component, the at least one pressure adjusting component and the_temperature adjusting component;
• wherein the substrate is of a same_material as the array of non-curable thermoplastic pillars;
• wherein the system further comprises:
• an apparatus for forming as the array of non-curable_thermoplastic pillars, the apparatus comprising:
• third and fourth rollers disposed with a gap between_them;
• the gap dimensioned to surround a sheet of_the non-curable thermoplastic material;
• relative rotation_of the first and second rollers being configured to draw_the sheet through the gap;
• at least one other pressure adjusting component configured to provide a predetermined pressure between third and fourth rollers such that the sheet of the non-curable thermoplastic material is contact with the fourth_roller;
• wherein a flexible mold is disposed on the fourth_roller, the flexible mold having an array of apertures and_a predetermined thickness, wherein each aperture of the array of apertures has a diameter of 200 nm to 15 um, a height of 400 nm to 15 um, and a center to center spacing of 400 nm to 45 um;
• and
• at least one other temperature adjusting component configured to heating at least the fourth roller such that_a surface of the sheet of the non-curable thermoplastic material is heated to a temperature at which nonuniform flow is produced;
• whereby the array of non-curable thermoplastic pillars is formed;
• another driver component configured to drive rotation of the third and fourth rollers;
• and
• wherein the system controller is also configured to control_the another driver component, the at least one other pressure adjusting component and the at least one other temperature adjusting component;
• wherein the sheet of the non-curable thermoplastic material_is a flexible sheet disposed on a film roll and is configured to_be provided to the third and fourth rollers and the first and second rollers in a continuous matter such that continuous rollto-roll processing for forming the array of non-curable thermoplastic pillars and the re-entrant structures.