Method for integrating a light emitting device

• US 9,570,427 B2
• Filed: 12/21/2015
• Issued: 02/14/2017
• Est. Priority Date: 06/17/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Bibl, Andreas, Griggs, Charles R.
• Primary Examiner(s): Schoenholtz, Joseph
• Application Number:
  US14/976,541
• Publication Number:
  US 20160111405A1
• Time in Patent Office: 421 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H01L 24/95 at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/165 Containers
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 27/0203 Particular design considerations for integrated circuits
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1244 for preventing breakage, peeling or short circuiting
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/0008 having p-n or hi-lo junctions
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/30 : containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/44 : characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/486 : adapted for surface mounting
• CPC Class Codes: H01L 33/52 : Encapsulations
• CPC Class Codes: H01L 33/54 : having a particular shape
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 : Reflective elements
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

Light emitting devices and methods of integrating micro LED devices into light emitting device are described. In an embodiment a light emitting device includes a reflective bank structure within a bank layer, and a conductive line atop the bank layer and elevated above the reflective bank structure. A micro LED device is within the reflective bank structure and a passivation layer is over the bank layer and laterally around the micro LED device within the reflective bank structure. A portion of the micro LED device and a conductive line atop the bank layer protrude above a top surface of the passivation layer.

Claims

1. A light emitting device comprising:

a substrate;

a bank layer on the substrate;

an array of bank openings in the bank layer;

an electrically conductive dam structure raised above the bank layer;

a corresponding array of micro LED devices within the array of bank openings; and

a passivation layer that spans directly over the bank layer and within the bank openings such that portions of the passivation layer within the array of bank openings are laterally around the corresponding array of micro LED devices, and wherein a portion of the each of the micro LED devices and the electrically conductive dam structure protrude above a top surface of the passivation layer.

2. The light emitting device of claim 1, wherein the electrically conductive dam structure comprises a ground tie line.

3. The light emitting device of claim 2, wherein the ground tie line is 1 μ

m-5 μ

m thick.

4. The light emitting device of claim 3, wherein the ground tie line comprises aluminum.

5. The light emitting device of claim 1, wherein the electrically conductive dam structure runs between rows of the bank openings.

6. The light emitting device of claim 5, wherein the electrically conductive dam structure runs between columns of the bank openings.

7. The light emitting device of claim 1, further comprising a corresponding array of electrically conductive bank structure layers within the array of bank openings, wherein the corresponding array of micro LED devices is bonded to the corresponding array of electrically conductive bank structure layers.

8. The light emitting device of claim 7, wherein the electrically conductive bank structure layers are 1 μ

m or less thick.

9. The light emitting device of claim 1, wherein the passivation layer comprises a thermoset material.

10. The light emitting device of claim 9, wherein the thermoset material is an acrylic.

11. The light emitting device of claim 1, wherein the substrate is a thin film transistor substrate.

12. The light emitting device of claim 1, wherein the electrically conductive dam structure comprises a dam layer and a ground tie line on the dam layer.

13. The light emitting device of claim 12, wherein the dam layer and the bank layer are formed of the same material.

14. The light emitting device of claim 1, wherein the electrically conductive dam structure comprises a dam layer and a via contact on the dam layer.