Re-emitting semiconductor carrier devices for use with LEDs and methods of manufacture

• US 9,293,622 B2
• Filed: 05/03/2010
• Issued: 03/22/2016
• Est. Priority Date: 05/05/2009
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Smith, Terry L., Leatherdale, Catherine A., Haase, Michael A., Miller, Thomas J., Sun, Xiaoguang, Yang, Zhaohui, Ballen, Todd A., Barnes, Amy S.
• Primary Examiner(s): SUN, YU-HSI DAVID
• Application Number:
  US13/264,487
• Publication Number:
  US 20120097983A1
• Time in Patent Office: 2,150 Days
• Field of Search: 257/84, 257/431, 257/80, 257/82
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 31/055 where light is absorbed and re-emitted at a different wavelength by the optical element directly associated or integrated with the PV cell, e.g. by using luminescent material, fluorescent concentrators or up-conversion arrangements
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: Y02E 10/52 PV systems with concentrators

Abstract

Re-emitting semiconductor constructions (RSCs) for use with LEDs, and related devices, systems, and methods are disclosed. A method of fabrication includes providing a semiconductor substrate, forming on a first side of the substrate a semiconductor layer stack, attaching a carrier window to the stack, and removing the substrate after the attaching step. The stack includes an active region adapted to convert light at a first wavelength λ₁ to visible light at a second wavelength λ₂, the active region including at least a first potential well. The attaching step is carried out such that the stack is disposed between the substrate and the carrier window, which is transparent to the second wavelength λ₂. The carrier window may also have a lateral dimension greater than that of the stack. The removal step is carried out so as to provide an RSC carrier device that includes the carrier window and the stack.

Claims

1. A re-emitting semiconductor construction (RSC) carrier device for use with an electroluminescent device, comprising:

a stack of epitaxial semiconductor layers, the stack being adapted to convert light at a first wavelength λ

₁ to visible light at a second wavelength λ

₂; and

a carrier window attached to the stack, the carrier window substantially transmitting light at the second wavelength λ

₂, and the carrier window being a glass carrier window that is attached to the stack by an adhesive, the adhesive being disposed as a layered structure on an ending surface of the stack and being sandwiched between the glass carrier window and the stack of epitaxial semiconductor layers to bond the glass carrier window to the stack.

2. The device of claim 1, wherein the carrier window has a maximum lateral dimension at least as large as that of the stack, and wherein the carrier window is sufficiently rigid to allow handling of the device without substantial damage to the semiconductor stack.

3. The device of claim 1, wherein the ending surface of the stack comprises a plurality of light extraction features facing towards the carrier window.

4. The device of claim 1, further comprising:

a second window attached to the stack such that the stack is disposed between the carrier window and the second window, the second window substantially transmitting light at the first wavelength λ

₁.

5. The device of claim 1, wherein the semiconductor layer stack includes a first potential well and a first absorbing layer closely adjacent to and having a band gap energy greater than a transition energy of the first potential well.

6. The device of claim 1, further comprising an electroluminescent device optically coupled to the stack of semiconductor layers and configured to emit light at the first wavelength.

7. The device of claim 1, wherein the adhesive is substantially transparent to the light at the second wavelength λ

₂.

8. The device of claim 1, wherein the adhesive has a lower refractive index than the carrier window.

9. The device of claim 1, wherein the carrier window has a thickness of at least 10 microns, and the carrier window is thicker than the stack.