Method for fabrication of optical element, and optical element having three-dimensional laminated structure

• US 20070031108A1
• Filed: 11/08/2004
• Published: 02/08/2007
• Est. Priority Date: 11/07/2003
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Sugita, Mitsuro, Yonehara, Takao
• Granted Patent: US 7,272,290 B2
• Time in Patent Office: Days
• US Class Current: 385/147
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/12 of the integrated circuit kind electric integrated circuits H01L27/00
• CPC Class Codes: G02B 6/12002 Three-dimensional structures
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices
• CPC Class Codes: G02B 6/13 Integrated optical circuits characterised by the manufacturing method
• CPC Class Codes: G02B 6/136 by etching
• CPC Class Codes: G02B 6/14 Mode converters

Abstract

A method for production of an optical element includes preparing a first member having formed on the surface of a first substrate 101 a first layer 103 by at least one of epitaxial growth and pore-making (micropore-making) and a second member having a porous layer for layer separation formed on a second substrate 104 and having formed thereon a second layer by at least one of epitaxial growth and pore-making (micropore-making), bonding the first layer 103 and the second layer, separating the second substrate 104 and the second layer of the second member from each other at the porous layer for layer separation in the second member, to form a laminated structure on the first substrate 101, forming a refraction index distribution pattern produced by a difference in refraction index in the plane of at least one of the first layer 103 and the second layer.

Claims

1. A method for production of an optical element comprising the steps of:

(A) forming a first layer on the surface of a first substrate by epitaxial growth or micropores-making;

(B) forming a porous layer on the surface of a second substrate;

(C) forming a second layer on the surface of the porous layer by epitaxial growth or micropores-making;

(D) bonding the first layer and the second layer to each other; and

(E) separating the second substrate from the second layer at the porous layer.

2. The method according to claim 1, further comprising step (F) of forming a refraction index distribution pattern on the first layer after step (A).

3. The method according to claim 1, further comprising step (G) of forming a refraction index distribution pattern on the second layer after step (C).

4. The method according to claim 1, wherein said steps (B) to (E) are repeated with the outermost layer on the first substrate as the first layer after step (E).

5. The method according to claim 4, wherein the refraction index distribution pattern formed on the second layer is a pattern having a periodic refraction index distribution formed in at least one direction as a result of repeating steps (B) to (E).

6. The method according to claim 4, wherein the second substrate in step (B) in a cycle is reused as the second substrate in step (B) in a following cycle.

7. The method according to claim 1, wherein step (B) is a step of forming a porous layer comprised of two layers different in porosity and the separating in step (E) is carried out at the boundary of the two layers.

8. The method according to claim 4, further comprising a step of placing a light emitting element layer between layers.

9. A method for production of an optical element comprising the steps of:

(a) forming alternatingly porous layers and microporous layers on a first substrate;

(b) forming a refraction index distribution pattern on the microporous layers collectively;

(c) bonding a second substrate to the porous layer or microporous layer being the outermost layer;

(d) separating a pair of microporous layers spaced by the porous layer at the porous layer;

(e) shifting the separated microporous layers from each other along an in-plane direction, and bonding the shifted microporous layers to each other; and

(f) repeating said steps (d) and (e) for each porous layer.

10. An optical element in which layers having refraction index distribution patterns formed thereon are deposited to form a three-dimensional periodic distribution of refraction index,

wherein a period of the refraction index in a direction of deposition is determined by the thickness of the plurality of layers and a sequence of refraction index distribution patterns of the deposited layers.

11. The optical element according to claim 10, wherein a light emitting layer is placed between the layers to form a photonic crystal laser.

12. The optical element according to claim 11, wherein a light emitting layer having in the direction of deposition a plurality of periodic refraction index distributions different to each other and emitting a light of a wavelength corresponding to each period is placed two-dimensionally along the layer.

13. An optical device comprising:

a light source layer emitting a light of a specific wavelength; and

a photonic crystals being formed on the light source layer and including a light emitting layer which receives the light emitted from the light source layer and emits a light of a wavelength different from a wavelength of the received light,

wherein the photonic crystals are photonic crystals in which the wavelength of the light emitted from the light source layer is out of a photonic band gap and the wavelength of the light emitted from the light emitting layer is within the photonic band gap.

14. The optical device according to claim 13, wherein a plurality of photonic-crystal layers are stacked, and the wavelength of a light emitted from the light emitting layer in a lower photonic crystal layer is out of a photonic band gap of an upper photonic crystal layer.