Antireflection structures with an exceptional low refractive index and devices containing the same
AssigneeNational Tsing Hua University
InventorsRong-Ming HO, Han-Yu HSUEH, Ming-Shiuan SHE, Hung-Ying CHEN, Shangjr GWO
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Abstract
Nanoporous polymers with gyroid nanochannels can be fabricated from the self-assembly of degradable block copolymer, polystyrene-b-poly(L-lactide) (PS-PLLA), followed by the hydrolysis of PLLA blocks. A well-defined nanohybrid material with SiO2 gyroid nanostructure in a PS matrix can be obtained using the nanoporous PS as a template for the sol-gel reaction. After subsequent UV degradation of the PS matrix, a highly porous inorganic gyroid network remains, yielding a single-component material with an exceptionally low refractive index (as low as 1.1).
Claims32
A process for preparing an antireflection structure comprising the following steps:
- a) coating a layer of an organic solvent solution of a block copolymer having first polymer blocks and second polymer blocks on a substrate modified with an organic material, wherein said first polymer is selected from the group consisting of poly(L-lactide), poly(D-lactide), poly(lactide), poly(acprolactone), and said second polymer is selected from the group consisting of poly(styrene), poly(vinylpyridine), and poly(acrylonitrile);
- b) solvent annealing the resultant coating layer from step a) by placing the coated substrate from step a) in an atmosphere containing a vapor of nonpreferential solvent so as to form a film of the block copolymer having the second polymer blocks as a matrix thereof and the first polymer blocks having a gyroid nanostructure in the matrix;
- c) selectively degrading said first polymer blocks to form correspondingly gyroid nanochannels in the matrix of said film;
- d) filling an inorganic filler into the gyroid nanochannels in the matrix of said film in a liquid mixture of a filler precursor under so-gel conditions;
- and
- e) removing the second polymer block matrix of said layer by using an ultraviolet light exposure, calcination, organic solvent, a supercritical fluid or a combination thereof to obtain an layer of porous inorganic gyroid network on the substrate.
Dependencies are inferred from the claim text.