Micro device with stabilization post

• US 9,035,279 B2
• Filed: 07/08/2013
• Issued: 05/19/2015
• Est. Priority Date: 07/08/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: LuxVue Techonology Corporation (Apple Inc.)
• Inventors: Hu, Hsin-Hua, Bibl, Andreas, Chang, Kevin K. C.
• Primary Examiner(s): Valentine, Jami M
• Application Number:
  US13/937,000
• Publication Number:
  US 20150008389A1
• Time in Patent Office: 680 Days
• Field of Search: 257/13, 438/26
• US Class Current: 257/13
• CPC Class Codes: H01L 2224/83005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 24/75 Apparatus for connecting with bump connectors or layer connectors
• CPC Class Codes: H01L 24/83 using a layer connector
• 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 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/005 Processes
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/04 with a quantum effect structure or superlattice, e.g. tunnel junction
• 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 33/32 containing nitrogen
• 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

A method and structure for stabilizing an array of micro devices is disclosed. A stabilization layer includes an array of stabilization cavities and array of stabilization posts. Each stabilization cavity includes sidewalls surrounding a stabilization post. The array of micro devices is on the array of stabilization posts. Each micro device in the array of micro devices includes a bottom surface that is wider than a corresponding stabilization post directly underneath the bottom surface.

Claims

1. A structure comprising:

a stabilization layer comprising an array of stabilization cavities and an array of stabilization posts, wherein each stabilization cavity includes a stabilization post and sidewalls that surround and are taller than a corresponding stabilization post; and

an array of micro devices on the array of stabilization posts;

wherein each micro device in the array of micro devices includes a bottom surface that is wider than a corresponding stabilization post directly underneath the bottom surface.

2. The structure of claim 1, further comprising a sacrificial layer between the stabilization layer and the array of micro devices, wherein the array of stabilization posts extend through a thickness of the sacrificial layer, and wherein the sacrificial layer spans along a side surface of each of the micro devices in the array of micro devices, the side surface running between a top surface and the bottom surface of each micro device in the array.

3. The structure of claim 2, wherein the sacrificial layer comprises an oxide or nitride.

4. The structure of claim 2, wherein the micro devices are micro LED devices.

5. The structure of claim 1, further comprising an array of bottom conductive contacts on the bottom surfaces of the array of micro devices.

6. The structure of claim 1, wherein the stabilization layer is formed of a thermoset material.

7. The structure of claim 6, wherein the thermoset material comprises benzocyclobutene (BCB).

8. The structure of claim 1, wherein the array of stabilization posts are separated by a pitch of 1 μ

m to 10 μ

m.

9. A structure comprising:

a stabilization layer comprising an array of stabilization cavities and an array of stabilization posts, wherein each stabilization cavity includes sidewalls that surround a corresponding stabilization post; and

an array of micro devices on the array of stabilization posts;

wherein each micro device in the array of micro devices includes a bottom surface that is wider than a corresponding stabilization post directly underneath the bottom surface, and each micro device includes an active device layer that is partially contained within a corresponding stabilization cavity.

10. The structure of claim 9, wherein the device layer includes a p-n diode.

11. The structure of claim 10, wherein the device layer includes a transistor.

12. The structure of claim 9, wherein the stabilization cavity sidewalls are taller than the stabilization posts.

13. The structure of claim 9, further comprising a sacrificial layer between the stabilization layer and the array of micro devices, wherein the array of stabilization posts extend through a thickness of the sacrificial layer, and wherein the sacrificial layer spans along a side surface of each of the micro devices in the array of micro devices, the side surface running between a top surface and the bottom surface of each micro device in the array.

14. The structure of claim 13, wherein the sacrificial layer comprises an oxide or nitride.

15. The structure of claim 9, further comprising an array of bottom conductive contacts on the bottom surfaces of the array of micro devices.

16. The structure of claim 9, wherein the stabilization layer is formed of a thermoset material.

17. The structure of claim 16, wherein the thermoset material comprises benzocyclobutene (BCB).

18. The structure of claim 9, wherein the array of stabilization posts are separated by a pitch of 1 μ

m to 10 μ

m.