Method to fabricate layered material compositions

• US 6,812,482 B2
• Filed: 08/28/2001
• Issued: 11/02/2004
• Est. Priority Date: 04/21/1999
• Status: Active Grant

• Current Assignee: National Technology & Engineering Solutions Of Sandia LLC (Honeywell International Inc.)
• Original Assignee: Sandia Corporation (Martin Marietta Corporation)
• Inventors: Fleming, James G., Lin, Shawn-Yu
• Primary Examiner(s): Mulpuri, Savitri
• Application Number:
  US09/941,820
• Publication Number:
  US 20030104700A1
• Time in Patent Office: 1,162 Days
• Field of Search: 430/321, 438/22, 438/800, 438/962, 372/39-41, 372/43
• US Class Current: 257/17
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices

Abstract

A new class of processes suited to the fabrication of layered material compositions is disclosed. Layered material compositions are typically three-dimensional structures which can be decomposed into a stack of structured layers. The best known examples are the photonic lattices. The present invention combines the characteristic features of photolithography and chemical-mechanical polishing to permit the direct and facile fabrication of, e.g., photonic lattices having photonic bandgaps in the 0.1-20μ spectral range.

Claims

1. A photonic or phononic lattice structure, comprising:

(a) a plurality of honeycomb layers stacked one above the other, with each honeycomb layer being formed by depositing and patterning layers of a first material and a second material to form a honeycomb structure from the first material with the remainder of the honeycomb layer comprising the second material, and with adjacent layers of the plurality of honeycomb layers being laterally displaced relative to each other along a diagonal thereof;

(b) an interconnection layer sandwiched between each pair of adjacent honeycomb layers for interconnecting the adjacent honeycomb layers at vertices thereof, with the interconnection layer being formed by depositing and patterning layers of the first material to form dots wherein the vertices are interconnected, with the remainder of the interconnection layer comprising the second material, wherein the first and the second materials are selected from the group consisting of polycrystalline silicon, amorphous silicon, silicon nitride, silicon dioxide, silicate glasses, III-V semiconductors, II-VI semiconductors, II-IV semiconductors, transparent oxides, sol-gel glasses and spin-on glasses.

2. The structure of claim 1 wherein a third material is substituted for the second material after formation of the plurality of honeycomb layers and each interconnection layer.

3. The structure of claim 1 further comprising a substrate whereon the each honeycomb layer and interconnection layer are supported.

4. The structure of claim 1 wherein the honeycomb structure comprises a plurality of interconnected rods, and the thickness of each honeycomb layer is equal to one-quarter of the length of one of the rods.

5. The structure of claim 4 wherein the dots are circular in the plane of the interconnection layer.

6. The structure of claim 5 wherein the circular dots have a diameter substantially equal to one-half the length of one of the rods.

7. The structure of claim 1 wherein the thickness of each interconnection layer is twice the thickness of each honeycomb layer.

8. The structure of claim 1 wherein the plurality of honeycomb layers forms a four-layer periodic structure having a bandgap therein.

9. A photonic or phononic lattice structure comprising a plurality of honeycomb layers formed from interconnected rods, with adjacent honeycomb layers being laterally shifted along a diagonal relative to each other and being connected together through an intervening layer, wherein the plurality of honeycomb layers forms a periodic structure having a bandgap therein, and with each rod comprising a material selected from the group consisting of polycrystalline silicon, amorphous silicon, silicon nitride, silicon dioxide, silicate glasses, III-V semiconductors, II-VT semiconductors, II-VI semiconductors, transparent oxides, sol-gel glasses and spin-on glasses.

10. The structure of claim 9 further including a substrate for supporting the plurality of honeycomb layers and each intervening layer.

11. The structure of claim 9 wherein the thickness of each honeycomb layer is equal to one-quarter of the length of each rod.

12. The structure of claim 9 wherein each intervening layer has a thickness equal to twice the thickness of the honeycomb layers.

13. A photonic or phononic lattice structure comprising a plurality of stacked hexagonal-pattern layers of interconnected rods separated by intervening interconnection layers having a triangular array of dots formed therein, with adjacent of the hexagonal-pattern layers being laterally displaced relative to each other along a diagonal, and with the dots connecting vertices of the interconnected rods of one hexagonal-pattern layer to the vertices of the interconnected rods of an adjacent hexagonal-pattern layer, with the interconnected rods and the dots comprising a first material, with a second material filling in spaces between the interconnected rods of each hexagonal-pattern layer and spaces between the dots of each interconnection layer, and with the first and the second materials being selected from the group consisting of polycrystalline silicon, amorphous silicon, silicon nitride, silicon dioxide, silicate glasses, III-V semiconductors, II-VI semiconductors, II-IV semiconductors, transparent oxides, sol-gel glasses, spin-on glasses, gases, air and vacuum.

14. The structure of claim 13 further comprising a substrate whereon the hexagonal-pattern layers and interconnection layers are supported.

15. The structure of claim 13 wherein the thickness of each hexagonal-pattern layer is equal to one-quarter of the length of each rod.

16. The structure of claim 15 wherein the thickness of each interconnection layer is twice the thickness of each hexagonal-pattern layer.

17. The structure of claim 13 wherein the dots are arranged in a triangular array.