Seed layer for fabrication of antireflective surface structures on optical elements
AssigneeThe Government of the United States of America, as represented by the Secretary of the Navy
InventorsLynda E. Busse, Jesse A. Frantz, Leslie Brandon Shaw, Jasbinder S. Sanghera, Ishwar D. Aggarwal, Menelaos K. Poutous
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Abstract
The invention relates to methods for fabricating antireflective surface structures (ARSS) on an optical element using a seed layer of material deposited on the surface of the optical element. The seed layer is removed during or after the etching, and serves to control etching time as well as the transmission region of the optical element having ARSS. Optical elements having ARSS on at least one surface are also provided.
Claims19
A method for fabricating antireflective surface structures, the method comprising:
- providing a dry-etchable optical substrate;
- applying a solution containing a seed layer to a surface of the optical substrate;
- and
- dry etching the seed layer and the optical substrate to remove portions of the seed layer and the optical substrate so as to form an optical element comprising a plurality of antireflective surface structures (ARSS), wherein a center-to-center spacing between adjacent antireflective surface structures is based on a refractive index of the optical substrate.
A method for fabricating antireflective surface structures, the method comprising:
- providing a dry-etchable optical substrate;
- applying a seed layer to a surface of the optical substrate;
- and
- dry etching the seed layer and the optical substrate to remove portions of the seed layer and the optical substrate so as to form an optical element comprising a plurality of antireflective surface structures (ARSS), wherein a center-to-center spacing between adjacent antireflective surface structures is based on a refractive index of the optical substrate,
- wherein the seed layer is applied by depositing particulates onto the surface of the optical substrate, depositing a layer of metal over the particulates, and removing the particulates prior to the dry etching step.
A method for fabricating antireflective surface structures, the method comprising:
- providing a dry-etchable optical substrate;
- applying a seed layer to a surface of the optical substrate at a temperature between 50° C. and 800° C. above room temperature, wherein the seed layer and the optical substrate have different coefficients of thermal expansion;
- cooling the seed layer and the optical substrate to room temperature such that a plurality of cracks form in the seed layer to form a template for etching;
- dry etching the seed layer and the optical substrate to remove portions of the seed layer and the optical substrate so as to form an optical element comprising a plurality of antireflective surface structures (ARSS), wherein a center-to-center spacing between adjacent antireflective surface structures is based on a refractive index of the optical substrate.
Dependencies are inferred from the claim text.