Patterned thin-film wavelength converter and method of making same

Patent metadata

Field	Value
Publication number	US-9373761-B2
Application number	US-201414494281-A
Country	US
Kind code	B2
Filing date	Sep 23, 2014
Priority date	Sep 23, 2014
Publication date	Jun 21, 2016
Grant date	Jun 21, 2016

Abstract

There is herein described a patterned thin-film wavelength converter which comprises a substrate having a first patterned surface with a first pattern, and a thin film deposited on the first patterned surface. The thin film consists of a wavelength converting material and has a second patterned surface that is distal from the substrate. The second patterned surface has a second pattern that is substantially the same as the first pattern of the substrate. An advantage of the patterned thin-film wavelength converter is that post-deposition processing is not required to produce a textured surface on the wavelength converting material. A method of making the patterned thin-film wavelength converter is also described.

First claim

What is claimed is:

1. A method of making a patterned thin-film wavelength converter, comprising:
(a) obtaining a substrate having a patterned surface with a pattern of features;
(b) depositing a conformal intermediate layer on the patterned surface of the substrate;
(c) depositing a thin film consisting of a wavelength converting material on the intermediate layer on the patterned surface of the substrate so that a surface of the thin film distal from the substrate has a pattern that is substantially the same as the pattern of the substrate; and
(d) removing the thin film from the substrate by a laser or chemical lift-off technique to obtain the patterned thin-film wavelength converter.

2. The method of claim 1 , wherein the intermediate layer is selected from cerium oxide, Si 3 N 4 , ZnO, HfO 2 , GaN, Ta 2 O 5 , and WO 3 .

3. The method of claim 1 , wherein the intermediate layer comprises cerium oxide.

4. The method of claim 1 , wherein the wavelength converting material is a garnet-based phosphor having a general formula A 3 B 5 O 12 :Ce, wherein A is Y, Sc, La, Gd, Lu, or Tb and B is Al, Ga or Sc.

5. The method of claim 1 , wherein the substrate is selected from aluminum nitride, boron nitride, yttrium aluminum garnet, polycrystalline diamond, single crystal diamond and beryllium oxide.

6. The method of claim 1 , wherein the features have a shape selected from domes, cones, pyramids, and mesas.

7. The method of claim 1 , wherein the pattern of features is selected from a hexagonal pattern, a triangular pattern and a rectangular pattern.

8. The method of claim 1 , wherein the features have a height from 100 nm to 10 μm.

9. The method of claim 1 , wherein the features have a height from 1 μm to 3 μm.

10. The method of claim 1 , wherein the features have a base width from 200 nm to 20 μm.

11. The method of claim 1 , wherein the features have a base width from 2 μm to 6 μm.

12. The method of claim 1 , wherein the features have a pitch from 200 nm to 20 μm.

13. The method of claim 1 , wherein the features have a pitch from 2 μm to 6 μm.

14. The method of claim 1 , wherein the method further comprises attaching the patterned thin-film wavelength converter to a light emitting diode uses a silicone adhesive.

Assignees

• Kundaliya Darshan
• Frischeisen Jörg
• Lenef Alan
• Sorg Jörg-Erich
• Von Malm Norwin
• Osram Sylvania Inc

Inventors

• Kundaliya Darshan
• Frischeisen Jörg
• Lenef Alan
• Sorg Jörg-Erich
• Von Malm Norwin

Classifications

• H10H20/8515

  not being in contact with the bodies · CPC title

• H10H20/882

  Scattering means (H10H20/82 takes precedence) · CPC title

• H10H20/0361

  of wavelength conversion means · CPC title

• H10H20/84

  Coatings, e.g. passivation layers or antireflective coatings · CPC title

• H10H20/8514 Primary

  characterised by their shape, e.g. plate or foil · CPC title