Magnetic alignment for flip chip microelectronic devices

• US 10,002,824 B2
• Filed: 06/10/2017
• Issued: 06/19/2018
• Est. Priority Date: 11/14/2015
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Agrawal, Ankur, Moola, Srinivas S., Sharan, Sujit, Govindarajan, Vijay
• Primary Examiner(s): Taylor, Earl
• Application Number:
  US15/619,463
• Publication Number:
  US 20170278783A1
• Time in Patent Office: 374 Days
• CPC Class Codes: H01L 21/4846 Leads on or in insulating or insulated substrates, e.g. metallisation H01L21/4821 takes precedence; metallisation of ceramics in general C04B41/51; printed circuits H05K3/00
• CPC Class Codes: H01L 2223/54426 for alignment
• CPC Class Codes: H01L 2223/54473 for use after dicing
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/10135 Alignment aids
• CPC Class Codes: H01L 2224/13082 Two-layer arrangements
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/13147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/16237 the bump connector connecting to a bonding area disposed in a recess of the surface of the item
• CPC Class Codes: H01L 2224/8113 using marks formed on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81132 using marks formed outside the semiconductor or solid-state body, i.e. "off-chip"
• CPC Class Codes: H01L 2224/81141 Guiding structures both on and outside the body
• CPC Class Codes: H01L 2224/81143 Passive alignment, i.e. self alignment, e.g. using surface energy, chemical reactions, thermal equilibrium
• CPC Class Codes: H01L 2224/81191 wherein the bump connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 23/02 Containers; Seals H01L23/12, H01L23/34, H01L23/48, H01L23/552, H01L23/66 take precedence; for memories G11C
• CPC Class Codes: H01L 23/49822 Multilayer substrates multilayer metallisation on monolayer substrate H01L23/498
• CPC Class Codes: H01L 23/49827 Via connections through the substrates, e.g. pins going through the substrate, coaxial cables H01L23/49822, H01L23/49833, H01L23/4985, H01L23/49861 take precedence
• CPC Class Codes: H01L 23/49838 Geometry or layout
• CPC Class Codes: H01L 23/49866 : characterised by the materials materials of the substrates H01L23/14, of the lead-frames H01L23/49579
• CPC Class Codes: H01L 23/544 : Marks applied to semiconductor devices or parts, e.g. registration marks, alignment structures, wafer maps test patterns for characterising or monitoring manufacturing processes H01L22/00
• CPC Class Codes: H01L 23/564 : Details not otherwise provided for, e.g. protection against moisture getters H01L23/26
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA

Abstract

Incorporating at least one magnetic alignment structure on a microelectronic device and incorporating at least one alignment coil within a microelectronic substrate, wherein the alignment coil may be powered to form a magnetic field to attract the magnetic alignment structure, thereby aligning the microelectronic device to the microelectronic substrate. After alignment, the microelectronic device may be electrically attached to the substrate. Embodiments may include additionally incorporating an alignment detection coil within the microelectronic substrate, wherein the alignment detection coil may be powered to form a magnetic field to detect variations in the magnetic field generated by the alignment coil in order verify the alignment of the microelectronic device to the microelectronic substrate.

Claims

1. A method for fabricating a microelectronic structure, comprising:

forming a microelectronic device having an attachment surface, an opposing back surface, and at least one side extending between the attachment surface and the back surface, wherein the microelectronic device attachment surface has at least one magnetic alignment structure and at least one interconnect structure extending therefrom;

forming a microelectronic substrate having a first surface and having an alignment coil formed therein;

forming an alignment detection coil within the microelectronic substrate;

forming a magnetic field with the alignment coil;

aligning the microelectronic device magnetic alignment structure to the magnetic field of the alignment coil;

forming a magnetic field with the alignment detection coil;

detecting the alignment of the microelectronic device magnetic alignment structure to the magnetic field of the magnetic alignment coil with the magnetic field of the alignment detection coil; and

electrically attaching the at least one interconnect structure of the microelectronic device to the microelectronic substrate.

2. The method of claim 1, wherein forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface, wherein a height of the at least one magnetic alignment structure is substantially the same as a height of the at least one interconnect structure.

3. The method of claim 1, wherein forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface, wherein a height of the at least one magnetic alignment structure is greater than a height of the at least one interconnect structure.

4. The method of claim 1, wherein forming the microelectronic device having at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one interconnect structure extending from the microelectronic device attachment surface, wherein the at least one magnetic alignment structure is positioned adjacent the at least one microelectronic device side.

5. The method of claim 1, wherein forming the microelectronic device further comprises forming the microelectronic device having at least one corner, wherein the at least one magnetic alignment structure comprises at least two magnetic alignment structures, and wherein a distance between one of the at least two magnetic alignment structures and the at least one microelectronic device corner closest thereto is greater than a distance between another of the at least two magnetic alignment structures and the at least one microelectronic device corner closest thereto.

6. The method of claim 1, wherein forming the microelectronic device having at least one magnetic alignment structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure comprising a ferromagnetic material extending from the microelectronic device attachment surface.

7. The method of claim 6, wherein forming the microelectronic device having at least one magnetic alignment structure comprising the ferromagnetic material extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure comprising nickel extending from the microelectronic device attachment surface.

8. A method for fabricating a microelectronic structure, comprising:

forming a microelectronic device having an attachment surface, an opposing back surface, and at least one side extending between the attachment surface and the back surface, wherein the microelectronic device attachment surface has at least one magnetic alignment structure and at least one interconnect structure extending therefrom;

forming a microelectronic substrate having a first surface and having an alignment coil formed therein, and having an unfilled opening extending into the microelectronic substrate from the microelectronic substrate first surface, wherein the unfilled opening is defined by at least one sidewall and a bottom and wherein a portion of the alignment coil is exposed to the unfilled opening at the least one unfilled opening sidewall;

forming a magnetic field with the alignment coil;

aligning the microelectronic device magnetic alignment structure to the magnetic field of the alignment coil; and

electrically attaching the at least one interconnect structure of the microelectronic device to the microelectronic substrate.

9. The method of claim 8, further including forming an alignment detection coil within the microelectronic substrate.

10. The method of claim 9, further comprising:

forming a magnetic field with the alignment detection coil;

detecting the alignment of the microelectronic device magnetic alignment structure to the magnetic field of the magnetic alignment coil with the magnetic field of the alignment detection coil.

11. The method of claim 9, wherein at least a portion of the alignment detection coil is exposed to the unfilled opening at the unfilled opening bottom.

12. The method of claim 8, wherein forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface, wherein a height of the at least one magnetic alignment structure is substantially the same as a height of the at least one interconnect structure.

13. The method of claim 8, wherein forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure and at least one interconnect structure extending from the microelectronic device attachment surface, wherein a height of the at least one magnetic alignment structure is greater than a height of the at least one interconnect structure.

14. The method of claim 8, wherein forming the microelectronic device having at least one interconnect structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one interconnect structure extending from the microelectronic device attachment surface, wherein the at least one magnetic alignment structure is positioned adjacent the at least one microelectronic device side.

15. The method of claim 8, wherein forming the microelectronic device further comprises forming the microelectronic device having at least one corner, wherein the at least one magnetic alignment structure comprises at least two magnetic alignment structures, and wherein a distance between one of the at least two magnetic alignment structures and the at least one microelectronic device corner closest thereto is greater than a distance between the other of the at least two magnetic alignment structures and the at least one microelectronic device corner closest thereto.

16. The method of claim 8, wherein forming the microelectronic device having at least one magnetic alignment structure extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure comprising a ferromagnetic material extending from the microelectronic device attachment surface.

17. The method of claim 16, wherein forming the microelectronic device having at least one magnetic alignment structure comprising a ferromagnetic material extending from the microelectronic device attachment surface comprises forming the microelectronic device having at least one magnetic alignment structure comprising nickel extending from the microelectronic device attachment surface.