Mass transfer tool

• US 9,511,498 B2
• Filed: 09/11/2015
• Issued: 12/06/2016
• Est. Priority Date: 09/07/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Higginson, John A., Bibl, Andreas, Albertalli, David
• Primary Examiner(s): Jackson, Stephen W
• Assistant Examiner(s): CLARK, CHRISTOPHER JAY
• Application Number:
  US14/852,366
• Publication Number:
  US 20160001450A1
• Time in Patent Office: 452 Days
• Field of Search: 361/234, 297/40
• US Class Current: 1/1
• CPC Class Codes: B25J 15/0085 with means for applying an electrostatic force on the object to be gripped
• CPC Class Codes: B81C 99/002 Apparatus for assembling MEMS, e.g. micromanipulators micromanipulators per se B25J7/00
• CPC Class Codes: H01L 21/67132 Apparatus for placing on an insulating substrate, e.g. tape
• CPC Class Codes: H01L 21/67144 Apparatus for mounting on conductive members, e.g. leadframes or conductors on insulating substrates
• CPC Class Codes: H01L 21/67259 Position monitoring, e.g. misposition detection or presence detection
• CPC Class Codes: H01L 2224/75251 in the lower part of the bonding apparatus, e.g. in the apparatus chuck
• CPC Class Codes: H01L 2224/75252 in the upper part of the bonding apparatus, e.g. in the bonding head
• CPC Class Codes: H01L 2224/75753 Means for optical alignment, e.g. sensors
• CPC Class Codes: H01L 2224/7598 specially adapted for batch processes
• CPC Class Codes: H01L 24/75 Apparatus for connecting with bump connectors or layer connectors
• 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: H02N 13/00 Clutches or holding devices using electrostatic attraction, e.g. using Johnson-Rahbek effect

Abstract

Systems and methods for transferring a micro device from a carrier substrate are disclosed. In an embodiment, a mass transfer tool includes an articulating transfer head assembly, a carrier substrate holder, and an actuator assembly to adjust a spatial relationship between the articulating transfer head assembly and the carrier substrate holder. The articulating transfer head assembly may include an electrostatic voltage source connection and a substrate supporting an array of electrostatic transfer heads.

Claims

1. A mass transfer tool comprising:

an articulating transfer head assembly including an electrostatic voltage source connection, the electrostatic voltage source connection to electrically connect with an array of electrostatic transfer heads, wherein the articulating transfer head assembly includes a mounting surface, the mounting surface to hold a substrate supporting the array of electrostatic transfer heads against the electrostatic voltage source connection;

a carrier substrate holder; and

an actuator assembly to adjust a spatial relationship between the articulating transfer head assembly and the carrier substrate holder.

2. The mass transfer tool of claim 1, wherein the electrostatic voltage source connection includes a resilient conductor to press against the substrate and to electrically connect the substrate with the electrostatic voltage source connection.

3. The mass transfer tool of claim 1, wherein the actuator assembly includes a first flexure coupled with the articulating transfer head assembly to constrain movement of the articulating transfer head assembly in a direction orthogonal to the mounting surface.

4. The mass transfer tool of claim 3, wherein the actuator assembly includes a second flexure coupled with the articulating transfer head assembly, and wherein the second flexure includes a second flexing surface oriented substantially parallel to a first flexing surface of the first flexure.

5. The mass transfer tool of claim 1, further comprising a first position sensor fixed relative to the mounting surface of the articulating transfer head assembly to detect a position of a carrier substrate on the carrier substrate holder.

6. The mass transfer tool of claim 1, further comprising a heater to heat the mounting surface.

7. The mass transfer tool of claim 1, further comprising a second electrostatic voltage source connection, the second electrostatic voltage source connection to electrically connect with the array of electrostatic transfer heads.

8. The mass transfer tool of claim 7, wherein the electrostatic voltage source connection includes a resilient conductor to press against the substrate and to electrically connect the substrate with the electrostatic voltage source connection, and the second electrostatic voltage source connection includes a second resilient conductor to press against the substrate and to electrically connect the substrate with the second electrostatic voltage source connection.

9. The mass transfer tool of claim 1, further comprising a force gauge coupled with the carrier substrate holder to measure a force applied to the carrier substrate holder.

10. The mass transfer tool of claim 1, further comprising a heater to heat the carrier substrate holder.

11. A mass transfer tool, comprising:

an articulating transfer head assembly including an electrostatic voltage source connection, the electrostatic voltage source connection to electrically connect with an array of electrostatic transfer heads;

a carrier substrate holder; and

an actuator assembly to adjust a spatial relationship between the articulating transfer head assembly and the carrier substrate holder, wherein the actuator assembly is to adjust a spatial relationship between the articulating transfer head assembly and the carrier substrate holder in at least six degrees of freedom.

12. The mass transfer tool of claim 11, wherein the actuator assembly includes a first actuator subassembly coupled with the articulating transfer head assembly to adjust an articulating transfer head assembly position in at least four degrees of freedom and a second actuator subassembly coupled with the carrier substrate holder to adjust a carrier substrate holder position in at least two degrees of freedom.

13. The mass transfer tool of claim 12, wherein the first actuator subassembly includes a flexure coupled with the articulating transfer head assembly to constrain movement of the articulating transfer head assembly in a direction orthogonal to a mounting surface of the articulating transfer head assembly.

14. The mass transfer tool of claim 13, further comprising a first position sensor fixed relative to the mounting surface of the articulating transfer head assembly to detect a position of a carrier substrate on the carrier substrate holder.

15. The mass transfer tool of claim 14, further comprising a second position sensor fixed relative to the carrier substrate holder to detect the articulating transfer head assembly position.

16. The mass transfer tool of claim 15, further comprising a third position sensor coupled with the actuator assembly to detect a deflection of the flexure.

17. A mass transfer tool, comprising:

an articulating transfer head assembly including an electrostatic voltage source connection, the electrostatic voltage source connection to electrically connect with an array of electrostatic transfer heads;

a carrier substrate holder;

an actuator assembly to adjust a spatial relationship between the articulating transfer head assembly and the carrier substrate holder;

a fiducial mark;

a first imaging device fixed relative to the articulating transfer head assembly and moveable relative to the fiducial mark, wherein the first imaging device includes a first imaging plane; and

a second imaging device fixed relative to the carrier substrate holder, wherein the second imaging device includes a second imaging plane, and wherein the fiducial mark is located between the first imaging plane and the second imaging plane.

18. The mass transfer tool of claim 17, wherein one or more of the first imaging device or the second imaging device includes a camera.