Method of fabricating sub-micron hemispherical and hemicylidrical structures from non-spherically shaped templates
A method for manufacturing hemi-cylindrical and hemi-spherical micro structures is provided. A pattern is formed onto a substrate, and a layer of material is subsequently grown onto the substrate. Due to growth characteristics, the layer will form radially symmetric features when grown to an appropriate thickness.
1. A method of making a stamper or stamper ancestor for fabricating an optical disk comprising:
forming a single layer substrate having a corrugated upper surface profile;
depositing a layer of material onto said upper surface so as to form a combined substrate and layer structure having an upper surface profile comprising an adjacent series of structures having a substantially hemi-cylindrical contour.
2. The method of claim 1 , wherein said forming comprises grooving a substrate with a spiral groove.
3. The method of claim 1 , wherein said forming comprises depositing, exposing, and developing a photoresist.
4. The method of claim 1 , wherein said forming comprises etching through an exposed and developed photoresist layer.
5. The method of claim 1 , wherein said forming comprises forming a substrate having an approximately sinusoidal upper surface profile.
6. The method of claim 1 , wherein said forming comprises forming a substrate having an approximately rectangular upper surface profile.
7. The method of claim 1 , additionally comprising: depositing metal onto said combined substrate and layer structure; removing said metal to form an inverted replica.
8. A method of making an optical data storage media, said method comprising:
forming a single layer substrate having a corrugated upper surface;
depositing at least one layer of optically active material over said substrate;
depositing a layer of material onto said optically active material so as to form lenses over said optically active material having a substantially hemi-cylindrical contour.
9. The method of claim 8 , wherein said depositing at least one layer of optically active material comprises depositing a phase change stack.
10. The method of claim 8 , additionally comprising bonding a substantially transparent cover sheet onto said lenses.
11. The method of claim 10 , wherein said cover sheet comprises polycarbonate.
12. A method of making an optical data storage medium comprising:
forming one or more convex substantially hemicylindrical structures with a deposition process characterized by substantially uniform growth on a single layer substrate;
serially replicating said structures to form a stamper having one or more convex substantially hemicylindrical structures;
molding a plastic blank using said stamper as part of a mold assembly to form a plastic substrate having one or more concave grooves with a substantially hemicylindrical contour; and
filling said grooves with a dielectric material so as to form convex lenses when viewed from the surface of the plastic blank opposite from the grooved side.
13. The method of claim 12 , wherein said plastic blank comprises polycarbonate.
14. The method of claim 1 , wherein depositing said layer of material comprises vacuum deposition.
15. The method of claim 1 , wherein depositing said layer of material comprises sputter coating said material onto said upper surface under vacuum conditions.
16. The method of claim 1 , wherein depositing said layer of material comprises a process characterized by substantially uniform growth.
17. The method of claim 1 , further comprising:
depositing a separation layer by accumulating inorganic material onto said upper surface.
18. The method of claim 17 , wherein said inorganic material is accumulating by a process selected from the group consisting of sputtering, electroplating, and other deposition technology.
19. The method of claim 1 , wherein said corrugated upper surface profile comprises a profile selected from the group consisting of (i) alternating convex and concave structures, (ii) grooves having an approximately sinusoidal cross section, (iii) grooves having a rectangular cross section, (iv) grooves having a trapezoidal cross section and (v) grooves having a flat sided geometric shape.
20. The method of claim 1 , wherein forming said substrate having a corrugated upper surface profile comprises the steps of:
forming a pattern of photo-sensitive synthetic resin on said substrate using one or more lithographic techniques;
etching said substrate to remove substrate material from between elements of said pattern of photo-sensitive synthetic resin; and
removing said pattern of photo-sensitive synthetic resin.
21. The method of claim 8 , wherein said layer of material deposited onto said optically active material comprises a material selected from the group consisting of gallium phosphide (GaP), gallium arsenide (GaAs), indium phosphide (InP), indium arsenide (InAs), germanium and indium antimonide (InSb).