Stabilization structure including sacrificial release layer and staging cavity

• US 9,166,114 B2
• Filed: 01/30/2013
• Issued: 10/20/2015
• Est. Priority Date: 12/11/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: LuxVue Techonology Corporation (Apple Inc.)
• Inventors: Hu, Hsin-Hua, Bibl, Andreas
• Primary Examiner(s): Mondt, Johannes P
• Application Number:
  US13/754,717
• Publication Number:
  US 20140159065A1
• Time in Patent Office: 993 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B81C 99/002 Apparatus for assembling MEMS, e.g. micromanipulators micromanipulators per se B25J7/00
• CPC Class Codes: H01L 21/56 Encapsulations, e.g. encapsulation layers, coatings
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68318 Auxiliary support including means facilitating the separation of a device or wafer from the auxiliary support
• CPC Class Codes: H01L 2221/68368 used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate
• CPC Class Codes: H01L 2221/68381 Details of chemical or physical process used for separating the auxiliary support from a device or wafer
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/7598 specially adapted for batch processes
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/83 using a layer connector
• CPC Class Codes: H01L 2224/95001 involving a temporary auxiliary member not forming part of the bonding apparatus, e.g. removable or sacrificial coating, film or substrate
• CPC Class Codes: H01L 2224/95136 involving guiding structures, e.g. shape matching, spacers or supporting members
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/75 Apparatus for connecting with bump connectors or layer connectors
• CPC Class Codes: H01L 24/80 Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
• CPC Class Codes: H01L 24/81 using a bump connector
• 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 27/153 in a repetitive configuration, e.g. LED bars
• 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 2924/1461 : MEMS
• CPC Class Codes: H01L 33/0093 : Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/48 : characterised by the semiconductor body packages

Abstract

A method and structure for stabilizing an array of micro devices is disclosed. The array of micro devices is held within an array of staging cavities on a carrier substrate. Each micro device is laterally surrounded by sidewalls of a corresponding staging cavity.

Claims

1. A stabilization structure comprising:

a carrier substrate;

an array of micro devices on the carrier substrate, wherein each micro device includes a device layer with a bottom surface;

a stabilization layer including an array of staging cavities corresponding to the array of micro devices, wherein each staging cavity includes sidewalls of the stabilization layer that completely laterally surround at least a portion of a thickness of the device layer of a corresponding micro device; and

a sacrificial release layer that completely covers a bottom surface forming a lower main surface of each staging cavity, spans along the sidewalls of each cavity, and spans underneath an entirety of the bottom surface of the device layer of the corresponding micro device;

wherein the array of micro devices is embedded in the sacrificial release layer within the array of staging cavities, wherein the stabilization layer spans directly underneath each micro device.

2. The stabilization structure of claim 1, wherein an embedded portion of each micro device is embedded in the sacrificial release layer within the array of staging cavities, and the embedded portion of each micro device is completely laterally surrounded by the sacrificial release layer.

3. The stabilization structure of claim 2, wherein the sacrificial release layer spans directly over the sidewalls of each of the staging cavities.

4. The stabilization structure of claim 1, wherein the sacrificial release layer comprises an oxide or nitride material.

5. The stabilization structure of claim 1, further comprising a sacrificial cap layer over the array of micro devices and the sidewalls of each of the staging cavities.

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

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

8. The stabilization structure of claim 1, wherein each micro device has a maximum width of 1 to 100 μ

m.

9. The stabilization structure of claim 8, wherein each staging cavity has a maximum width of 1 to 100 μ

m.

10. The stabilization structure of claim 8, wherein each staging cavity has a maximum width between 0.5μ

m and 20 μ

m larger than the maximum width of a corresponding micro device within the staging cavity.

11. The stabilization structure of claim 8, wherein the sidewalls are 0.5 to 20 μ

m wide.

12. The stabilization structure of claim 1, further comprising a conductive contact on the bottom surface of the device layer of each micro device.

13. The stabilization structure of claim 12, wherein each micro device is a micro LED device.

14. The stabilization structure of claim 13, further comprising a conductive contact on a top surface of each micro LED device.

15. The stabilization structure of claim 12, wherein each micro device is a micro chip.

16. The stabilization structure of claim 15, further comprising a plurality of laterally separate conductive contacts on the bottom surface of the device layer of each micro chip.

17. The stabilization structure of claim 16, wherein at least one of the laterally separate conductive contacts on the bottom surface of the device layer of each micro chip is electrically connected with a landing pad of the respective micro chip.

18. The stabilization structure of claim 12, wherein each conductive contact comprises a diffusion barrier and a bonding layer between the diffusion barrier and the sacrificial release layer.

19. The stabilization structure of claim 1, wherein each staging cavity shares one of the sidewalls with an adjacent staging cavity.

20. The stabilization structure of claim 1, wherein each staging cavity shares sidewalls with a plurality of corresponding adjacent staging cavities.