METHODS FOR BONDING SUBSTRATES

• US 20200135690A1
• Filed: 07/24/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: LIANTO, PRAYUDI, SEE, GUAN HUEI, THIRUNAVUKARASU, SRISKANTHARAJAH, SUNDARRAJAN, ARVIND, DAI, XUNDONG, FUNG, PETER KHAI MUM
• Granted Patent: US 11,309,278 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 20/023 Thermo-compression bonding
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: H01L 2224/02166 Collar structures
• CPC Class Codes: H01L 2224/0345 Physical vapour deposition [PVD], e.g. evaporation, or sputtering
• CPC Class Codes: H01L 2224/03462 Electroplating
• CPC Class Codes: H01L 2224/0348 Permanent masks, i.e. masks left in the finished device, e.g. passivation layers
• CPC Class Codes: H01L 2224/0361 Physical or chemical etching
• CPC Class Codes: H01L 2224/03616 Chemical mechanical polishing [CMP]
• CPC Class Codes: H01L 2224/039 Methods of manufacturing bonding areas involving a specific sequence of method steps
• CPC Class Codes: H01L 2224/03901 with repetition of the same manufacturing step
• CPC Class Codes: H01L 2224/04 Structure, shape, material or disposition of the bonding areas prior to the connecting process
• CPC Class Codes: H01L 2224/05017 comprising protrusions or indentations
• CPC Class Codes: H01L 2224/05073 Single internal layer
• CPC Class Codes: H01L 2224/05124 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/05147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05166 Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/05547 comprising a core and a coating
• CPC Class Codes: H01L 2224/05564 Only on the bonding interface of the bonding area
• CPC Class Codes: H01L 2224/056 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 2224/05609 Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/05611 : Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/05613 : Bismuth [Bi] as principal constituent
• CPC Class Codes: H01L 2224/05616 : Lead [Pb] as principal constituent
• CPC Class Codes: H01L 2224/05639 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/05644 : Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/05647 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05666 : Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/08 : of an individual bonding area
• CPC Class Codes: H01L 2224/08145 : the bodies being stacked
• CPC Class Codes: H01L 2224/29124 : Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/29147 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/2957 : Single coating layer
• CPC Class Codes: H01L 2224/29582 : Two-layer coating
• CPC Class Codes: H01L 2224/29609 : Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/29611 : Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/29613 : Bismuth [Bi] as principal constituent
• CPC Class Codes: H01L 2224/29616 : Lead [Pb] as principal constituent
• CPC Class Codes: H01L 2224/29639 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/29644 : Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/29647 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/29666 : Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/80 : 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 2224/80203 : Thermocompression bonding, e.g. diffusion bonding, pressure joining, thermocompression welding or solid-state welding
• CPC Class Codes: H01L 2224/80357 : being flush with the surface
• CPC Class Codes: H01L 2224/80815 : Reflow soldering
• CPC Class Codes: H01L 2224/80896 : between electrically insulating surfaces, e.g. oxide or nitride layers
• CPC Class Codes: H01L 2224/80905 : Combinations of bonding methods provided for in at least two different groups from H01L2224/808 - H01L2224/80904
• CPC Class Codes: H01L 2224/83031 : by chemical means, e.g. etching, anodisation
• CPC Class Codes: H01L 2224/83092 : Atmospheric pressure
• CPC Class Codes: H01L 2224/83097 : Heating
• CPC Class Codes: H01L 2224/83375 : having an external coating, e.g. protective bond-through coating
• CPC Class Codes: H01L 2224/83379 : Material
• CPC Class Codes: H01L 2224/83895 : between electrically conductive surfaces, e.g. copper-copper direct bonding, surface activated bonding
• CPC Class Codes: H01L 2224/94 : at wafer-level, i.e. with connecting carried out on a wafer comprising a plurality of undiced individual devices
• CPC Class Codes: H01L 24/03 : Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/08 : of an individual bonding area
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• 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 24/83 : using a layer connector
• CPC Class Codes: H01L 24/94 : at wafer-level, i.e. with connecting carried out on a wafer comprising a plurality of undiced individual devices
• 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 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/013 : Alloys
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/381 : Pitch distance

Abstract

Methods for bonding substrates used, for example, in substrate-level packaging, are provided herein. In some embodiments, a method for bonding substrates includes: performing electrochemical deposition (ECD) to deposit at least one material on each of a first substrate and a second substrate, performing chemical mechanical polishing (CMP) on the first substrate and the second substrate to form a bonding interface on each of the first substrate and the second substrate, positioning the first substrate on the second substrate so that the bonding interface on the first substrate aligns with the bonding interface on the second substrate, and bonding the first substrate to the second substrate using the bonding interface on the first substrate and the bonding interface on the second substrate.

Claims

1. A method for bonding substrates, comprising:

performing electrochemical deposition (ECD) to deposit at least one material on each of a first substrate and a second substrate;

performing chemical mechanical polishing (CMP) on the first substrate and the second substrate to form a bonding interface on each of the first substrate and the second substrate;

positioning the first substrate on the second substrate so that the bonding interface on the first substrate aligns with the bonding interface on the second substrate; and

bonding the first substrate to the second substrate using the bonding interface on the first substrate and the bonding interface on the second substrate.

2. The method of claim 1, wherein the at least one material is at least one of Sn, Ag, Pb, In, Bi, or Au.

3. The method of claim 2, wherein at least one of the first substrate and the second substrate comprises at least one of Cu or Al, and at least one of Si, oxide, or a polymer, and

wherein the at least one material is deposited on the at least one of Cu or Al.

4. The method of claim 1, wherein the at least one material is deposited on each of the first substrate and the second substrate to a thickness not exceeding 5 μ

m.

5. The method of claim 1, wherein after CMP is performed, the bonding interface on the first substrate and the bonding interface on the second substrate each has a thickness not exceeding 100 nm.

6. The method of claim 1, wherein bonding the first substrate to the second substrate is performed at atmospheric pressure.

7. The method of claim 1, wherein bonding the first substrate to the second substrate is performed at a temperature not exceeding 250°

C.

8. The method of claim 1 further comprising:

performing physical vapor deposition (PVD) to deposit a first material on each of the first substrate and the second substrate,

wherein performing ECD to deposit the at least one material on each of the first substrate and the second substrate comprises performing ECD to deposit a second material on each of the first substrate and the second substrate, and

wherein performing CMP on the first substrate and the second substrate to form the bonding interface on each of the first substrate and the second substrate comprises performing CMP on the first substrate and the second substrate to form a bonding interface of the second material on each of the first substrate and the second substrate.

9. The method of claim 8, wherein the first material is one of Ti, Cu, and combinations thereof, and the second material is one of Sn, Ag, Pb, In, Bi, or Au.

10. The method of claim 9, wherein at least one of the first substrate and the second substrate comprises at least one of Cu or Al, and at least one of Si, oxide, or a polymer, and

wherein the first material is deposited on the at least one of Cu or Al, and the second material is deposited on the first material.

11. The method of claim 8, wherein the first material is deposited to a thickness not exceeding 1 μ

m, and

wherein the second material is deposited to a thickness not exceeding 5 μ

m.

12. The method of claim 8, wherein after CMP is performed, the bonding interface and the first material on the first substrate have a combined thickness not exceeding 100 nm, and the bonding interface and the first material on the second substrate have a combined thickness not exceeding 100 nm.

13. The method of claim 8, wherein bonding the first substrate to the second substrate is performed at atmospheric pressure.

14. The method of claim 8, wherein bonding the first substrate to the second substrate is performed at a temperature not exceeding 250°

C.

15. A nontransitory computer readable storage medium having stored thereon instructions that when executed by a processor perform a method for bonding substrates, the method comprising:

performing electrochemical deposition (ECD) to deposit at least one material on each of a first substrate and a second substrate;

performing chemical mechanical polishing (CMP) on the first substrate and the second substrate to form a bonding interface on each of the first substrate and the second substrate;

positioning the first substrate on the second substrate so that the bonding interface on the first substrate aligns with the bonding interface on the second substrate; and

bonding the first substrate to the second substrate using the bonding interface on the first substrate and the bonding interface on the second substrate.

16. The nontransitory computer readable storage medium of claim 15, wherein the at least one material is at least one of Sn, Ag, Pb, In, Bi, or Au,

wherein at least one of the first substrate and the second substrate comprises at least one of Cu or Al, and at least one of Si, oxide, or a polymer,

wherein the at least one material is deposited on the at least one of Cu or Al, and

wherein the at least one material is deposited on each of the first substrate and the second substrate to a thickness not exceeding 5 μ

m.

17. The nontransitory computer readable storage medium of claim 15, wherein after CMP is performed, the bonding interface on the first substrate and the bonding interface on the second substrate each has a thickness not exceeding 100 nm.

18. The nontransitory computer readable storage medium of claim 15, wherein bonding the first substrate to the second substrate is performed at atmospheric pressure, and

wherein bonding the first substrate to the second substrate is performed at a temperature not exceeding 250°

C.

19. A method for bonding substrates, comprising:

performing electrochemical deposition (ECD) to deposit at least one material on each of a first substrate and a second substrate and form a bonding interface on each of the first substrate and the second substrate;

positioning the first substrate on the second substrate so that the bonding interface on the first substrate aligns with the bonding interface on the second substrate; and

bonding the first substrate to the second substrate using the bonding interface on the first substrate and the bonding interface on the second substrate.

20. The method of claim 19, further comprising, after performing ECD, performing chemical mechanical polishing (CMP) on the first substrate and the second substrate such that the formed bonding interface on each of the first substrate and the second substrate has a thickness not exceeding 100 nm.