POLARIZED WHITE LIGHT DEVICES USING NON-POLAR OR SEMIPOLAR GALLIUM CONTAINING MATERIALS AND TRANSPARENT PHOSPHORS

• US 20140175377A1
• Filed: 02/27/2014
• Published: 06/26/2014
• Est. Priority Date: 04/07/2009
• Status: Abandoned Application

• Current Assignee: Soraa, Inc.
• Original Assignee: Soraa, Inc.
• Inventors: D'EVELYN, MARK P., CHAKRABORTY, ARPAN
• Application Number:
  US14/191,950
• Publication Number:
  US 20140175377A1
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material

Abstract

A light emitting device includes a substrate having a surface region and a light emitting diode overlying the surface region. The light emitting diode is fabricated on a semipolar or nonpolar GaN containing substrate and emits electromagnetic radiation of a first wavelength. The diode includes a quantum well region characterized by an electron wave function and a hole wave function. The electron wave function and the hole wave function are substantially overlapped within a predetermined spatial region of the quantum well region. The device has a transparent phosphor overlying the light emitting diode. The phosphor is excited by the substantially polarized emission to emit electromagnetic radiation of a second wavelength.

Claims

1. A packaged light emitting device comprising:

a substrate member having a surface region;

at least one light emitting diode overlying the surface region, the at least one light emitting diode being fabricated on a substrate characterized by a semipolar or nonpolar GaN orientation, the at least one light diode emitting electromagnetic radiation of a first wavelength;

a luminescent material characterized by a first refractive index being excited by emission from the at least one light emitting diode to emit electromagnetic radiation of a second wavelength; and

a dispersion medium characterized by a second refractive index containing the luminescent material;

wherein the second refractive index is about the same as the first refractive index; and

wherein at least one side of the at least one light emitting diode is in direct contact with the dispersion medium.

2. The packaged light emitting device of claim 1, wherein the dispersion medium comprises a scattering free medium for radiation of the first wavelength and for the radiation of the second wavelength.

3. The packaged light emitting device of claim 1, wherein the dispersion medium comprises silicone.

4. The packaged light emitting device of claim 1, further comprising a second dispersion medium encapsulating the first dispersion medium.

5. The packaged light emitting device of claim 1, further comprising a submount, wherein the at least one light emitting diode is mounted to the submount and the submount is mounted to the surface region.

6. The packaged light emitting device of claim 1, wherein the at least one light emitting diode has a top side, a bottom side, and three sides connecting the top side and the bottom side.