Methods for wafer-level packaging of microfeature devices and microfeature devices formed using such methods

• US 7,807,505 B2
• Filed: 08/30/2005
• Issued: 10/05/2010
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: Mirion Technologies Incorporated (American Capital Limited)
• Original Assignee: Micron Technology, Inc.
• Inventors: Farnworth, Warren M., Wood, Alan G.
• Primary Examiner(s): Huynh; Andy
• Assistant Examiner(s): HO, HOANG QUAN TRAN
• Application Number:
  US11/215,780
• Publication Number:
  US 20070045875A1
• Time in Patent Office: 1,862 Days
• Field of Search: None
• US Class Current: 438/113
• CPC Class Codes: H01L 21/568 Temporary substrate used as encapsulation process aid H01L21/4832 and H01L21/566 take precedence
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2224/04105 Bonding areas formed on an encapsulation of the semiconductor or solid-state body, e.g. bonding areas on chip-scale packages
• CPC Class Codes: H01L 2224/12105 Bump connectors formed on an encapsulation of the semiconductor or solid-state body, e.g. bumps on chip-scale packages
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/73259 Bump and HDI connectors
• CPC Class Codes: H01L 2224/81005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2225/06513 Bump or bump-like direct electrical connections between devices, e.g. flip-chip connection, solder bumps
• CPC Class Codes: H01L 2225/06586 Housing with external bump or bump-like connectors
• CPC Class Codes: H01L 24/96 the devices being encapsulated in a common layer, e.g. neo-wafer or pseudo-wafer, said common layer being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/97 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 25/0652 the devices being arranged next and on each other, i.e. mixed assemblies
• CPC Class Codes: H01L 25/0657 Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/18161 of a flip chip

Abstract

Methods for wafer-level packaging of microfeature devices and microfeature devices formed using such methods are disclosed herein. A method for packaging microfeature devices in accordance with an embodiment of the invention can include releasably attaching a plurality of first known good microelectronic dies to a carrier substrate in a desired arrangement. In several embodiments, for example, the first dies can be releasably attached to an attachment feature on the carrier substrate. The method can also include attaching one or more second known good microelectronic dies to the individual first dies in a stacked configuration to form a plurality of stacked devices. The method further includes at least partially encapsulating the stacked devices and separating the stacked devices from each other.

Claims

1. A method for packaging microfeature devices, the method comprising:

releasably attaching a plurality of first known good microelectronic dies to a generally rigid, temporary carrier substrate in a desired arrangement, wherein the carrier substrate is patterned with the desired arrangement before releasably attaching the first known good dies, and wherein the temporary carrier substrate has a form factor corresponding to a form factor of a semiconductor wafer;

attaching one or more second known good microelectronic dies to the individual first dies in a stacked configuration to form a plurality of stacked devices;

at least partially encapsulating the stacked devices; and

separating the stacked devices from each other.

2. The method of claim 1, further comprising removing the first dies and corresponding second dies from the carrier substrate after at least partially encapsulating the stacked devices and before separating the stacked devices from each other.

3. The method of claim 1 wherein the individual first dies include an integrated circuit and an array of terminals electrically coupled to the integrated circuit, and wherein the method further comprises:

removing the stacked devices from the carrier substrate after at least partially encapsulating the stacked devices and before separating the stacked devices from each other; and

attaching electrical couplers to corresponding terminals on the first dies before separating the stacked devices from each other.

4. The method of claim 1 wherein at least partially encapsulating the stacked devices includes encapsulating the stacked devices using a film-assisted molding process.

5. The method of claim 1 wherein at least partially encapsulating the stacked devices includes encapsulating the stacked devices using a glob-type dispensing process.

6. The method of claim 1 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching an active side of the individual first dies to the carrier substrate; and

attaching one or more second known good microelectronic dies to the individual first dies includes electrically coupling terminals on the individual second dies to corresponding pads at a back side of the individual first dies.

7. The method of claim 1 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching a redistribution layer on an active side of the individual first dies to the carrier substrate; and

attaching one or more second known good microelectronic dies to the individual first dies includes electrically coupling terminals on the individual second dies to corresponding pads at a back side of the individual first dies.

8. The method of claim 1 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching a back side of the individual first dies to the carrier substrate; and

attaching one or more second known good microelectronic dies to the individual first dies includes electrically coupling pads on the individual second dies to corresponding terminals at an active side of the individual first dies.

9. The method of claim 1, further comprising forming redistribution layers on the second dies after at least partially encapsulating the stacked devices and before separating the stacked devices from each other.

10. The method of claim 1 wherein:

the individual first dies include an active side, a back side opposite the active side, and a plurality of terminals at the active side and arranged in a first pattern;

the individual second dies include an array of external contacts arranged in a second pattern different than the first pattern;

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching the back side of the individual first dies to the carrier substrate; and

wherein the method further comprises forming a redistribution layer on the individual first dies after releasably attaching the first dies to the carrier substrate and before attaching the second dies to the first dies, the redistribution layers including a plurality of pads arranged in the second pattern.

11. The method of claim 1 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching first dies having a first footprint;

attaching one or more second known good dies to the individual first dies includes attaching a plurality of second dies to corresponding first dies, the second dies having a second footprint smaller than the first footprint; and

wherein the method further comprises attaching one or more third known good dies to the individual first dies before at least partially encapsulating the stacked devices, the third dies having a third footprint smaller than the first footprint.

12. The method of claim 1 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching first dies having corresponding pairs of devices to the carrier substrate, the individual pairs including devices with logic-type circuitry and devices with memory circuitry;

attaching one or more second known good dies to the individual first dies includes attaching imaging dies to the first dies, the individual imaging dies including integrated circuitry and an image sensor electrically coupled to the integrated circuitry; and

wherein the method further comprises forming optical elements over the individual image sensors before separating the stacked devices from each other.

13. The method of claim 12 wherein forming optical elements over the individual image sensors occurs before at least partially encapsulating the stacked devices.

14. The method of claim 12 wherein forming optical elements over the individual image sensors occurs after at least partially encapsulating the stacked devices.

15. The method of claim 1 wherein releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching the individual first dies to an attachment feature on the carrier substrate.

16. The method of claim 1 wherein attaching one or more second known good microelectronic dies to the individual first dies includes using a reflow process to attach the second dies to the first dies.

17. The method of claim 1, further comprising removing the carrier substrate from the stacked devices after at least partially encapsulating the stacked devices and before separating the stacked devices from each other, and wherein separating the stacked devices from each other comprises cutting the encapsulant to separate the stacked devices from each other.

18. The method of claim 1, further comprising thinning the first dies before releasably attaching the first dies to the carrier substrate.

19. The method of claim 1, further comprising thinning the first dies after releasably attaching the first dies to the carrier substrate and before attaching the one or more second dies to the individual first dies.

20. A method for packaging microfeature devices, the method comprising:

releasably attaching a plurality of first known good microelectronic dies to a generally rigid, temporary carrier substrate in a desired arrangement such that the carrier substrate is substantially populated with first dies, wherein the carrier substrate is patterned with the desired arrangement before releasably attaching the first known good dies, and wherein the carrier substrate has a shape and a thickness corresponding to a shape and a thickness of a semiconductor wafer;

attaching and electrically coupling second known good microelectronic dies to the individual first dies in a stacked configuration to form a plurality of stacked units;

disposing an encapsulant between the stacked units;

removing the carrier substrate from the stacked units after disposing the encapsulant between the stacked units; and

cutting the encapsulant to separate the stacked units from each other.

21. The method of claim 20 wherein the individual first dies include an integrated circuit and an array of terminals electrically coupled to the integrated circuit, and wherein the method further comprises:

attaching electrical couplers to corresponding terminals on the first dies after removing carrier substrate from the stacked units and before cutting the encapsulant to separate the stacked units from each other.

22. The method of claim 20 wherein disposing an encapsulant between the stacked units includes using a film-assisted molding process to at least partially encapsulate the stacked units.

23. The method of claim 20 wherein disposing an encapsulant between the stacked units includes using a glob-type dispensing process to at least partially encapsulate the stacked units.

24. The method of claim 20 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching an active side of the individual first dies to the carrier substrate; and

attaching and electrically coupling second known good microelectronic dies to the individual first known good dies includes electrically coupling terminals on the individual second dies to corresponding pads at a back side of the individual first dies.

25. The method of claim 24 wherein the individual first dies include redistribution layers at the active side, and wherein releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching the redistribution layer to the carrier substrate.

26. The method of claim 20 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching a back side of the individual first dies to the carrier substrate; and

attaching and electrically coupling second known good microelectronic dies to the individual first dies includes electrically coupling pads on the individual second dies to corresponding terminals at an active side of the individual first dies.

27. The method of claim 20, further comprising forming redistribution layers on the second dies after disposing an encapsulant between the stacked units and before cutting the encapsulant to separate the stacked units from each other.

28. The method of claim 20 wherein:

the individual first dies include an active side, a back side opposite the active side, and a plurality of terminals at the active side and arranged in a first pattern;

the individual second dies include an array of external contacts arranged in a second pattern different than the first pattern;

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching the back side of the individual first dies to the carrier substrate; and

wherein the method further comprises forming a redistribution layer on the individual first dies after releasably attaching the first dies to the carrier substrate and before attaching the second dies to the first dies, the redistribution layers including a plurality of pads arranged in the second pattern.

29. The method of claim 20 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching first dies having a first footprint;

attaching and electrically coupling second known good dies to the individual first dies includes attaching a plurality of second dies to corresponding first dies, the second dies having a second footprint smaller than the first footprint; and

wherein the method further comprises attaching one or more third known good dies to the individual first dies before disposing an encapsulant between the stacked units, the third dies having a third footprint smaller than the first footprint.

30. The method of claim 20 wherein:

releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching first dies having corresponding pairs of devices to the carrier substrate, the individual pairs including devices with logic-type circuitry and devices with memory circuitry;

attaching and electrically coupling second known good dies to the individual first dies includes attaching imaging dies to the first dies, the individual imaging dies including integrated circuitry and an image sensor electrically coupled to the integrated circuitry; and

wherein the method further comprises forming optical elements over the individual image sensors before cutting the encapsulant to separate the stacked units from each other.

31. The method of claim 30 wherein forming optical elements over the individual image sensors occurs before disposing an encapsulant between the stacked units.

32. The method of claim 30 wherein forming optical elements over the individual image sensors occurs after disposing an encapsulant between the stacked units.

33. The method of claim 20 wherein releasably attaching a plurality of first known good microelectronic dies to a carrier substrate includes releasably attaching the individual first dies to an attachment feature on the carrier substrate.

34. The method of claim 20, further comprising attaching third dies to the second dies in a stacked configuration to form a plurality of stacked units before disposing an encapsulant between the stacked units.

35. A method for manufacturing microfeature devices including first known good microelectronic dies and second known good microelectronic dies, the first dies and second dies including integrated circuitry and terminals electrically coupled to the integrated circuitry, the method comprising:

populating a generally rigid, temporary support member with a plurality of first dies such that the support member is substantially populated with the first dies, wherein the support member is patterned with a predetermined arrangement for the first dies before the support member is populated, and wherein the support member has a form factor corresponding to a form factor of a semiconductor wafer;

coupling second dies to the individual first dies in a stacked configuration;

depositing an encapsulant onto the support member to at least partially encapsulate the first dies and the second dies;

removing the first dies from the support member after at least partially encapsulating the first dies and the second dies; and

cutting the encapsulant to separate the first dies.

36. The method of claim 35, further comprising attaching electrical couplers to corresponding terminals on the first dies before cutting the encapsulant to singulate the first dies.

37. The method of claim 35, further comprising forming redistribution layers on the second dies after at least partially encapsulating the first dies and the second dies and before cutting the encapsulant to separate the first dies.

38. The method of claim 35, further comprising forming redistribution layers on the first dies before coupling the second dies to the individual first dies, and wherein coupling the second dies to the first dies includes electrically coupling the second dies to the redistribution layers on the first dies.

39. The method of claim 35 wherein populating a support member with a plurality of first dies includes releasably attaching the first dies to an attachment feature on the support member.

40. The method of claim 35, further comprising stacking third dies on the second dies before depositing an encapsulant onto the support member, and wherein the method further comprises at least partially encapsulating the third dies.

41. The method of claim 35 wherein depositing an encapsulant over the first and second dies to at least partially encapsulate the first and second dies comprises depositing the encapsulant using a film-assisted molding process.

42. The method of claim 35 wherein depositing an encapsulant over the first and second dies to at least partially encapsulate the first and second dies comprises depositing the encapsulant using a glob-type dispensing process.

43. A method for manufacturing microfeature devices, the method comprising:

providing a plurality of first known good microelectronic dies and a plurality of second known good microelectronic dies;

patterning a generally rigid, temporary support member with a desired arrangement for the first dies, wherein the carrier substrate has a shape and a thickness corresponding to a shape and a thickness of a semiconductor wafer;

releasably attaching the first dies to the generally rigid, temporary support member in the desired arrangement;

stacking second dies on corresponding first dies to form a plurality of stacked subassemblies;

heating the subassemblies to reflow external contacts on the first dies and second dies to electrically couple the first dies to the second dies;

depositing an encapsulant onto the temporary support member to at least partially encapsulate the first dies and second dies;

removing the temporary support member; and

singulating the first dies.