Selective Dielectric Capping for Hybrid Bonding
A method for increasing dielectric bonding strength during wafer-level processing is incorporated into a hybrid bonding process. A method may include immersing a substrate into a chemical bath at atmospheric conditions where the chemical bath forms a self-assembled monolayer on metal surfaces of the substrate and selectively depositing a high-k dielectric material to form a dielectric cap on dielectric surfaces of the substrate absent of the self-assembled monolayer.
1 . A method for increasing dielectric bonding strength during wafer-level processing, comprising:
immersing a substrate into a chemical bath, wherein the chemical bath forms a self-assembled monolayer on at least one metal surface of the substrate; and
selectively depositing a dielectric material to form a dielectric cap on at least one dielectric surface of the substrate absent of the self-assembled monolayer.
2 . The method of claim 1 , wherein immersing the substrate into the chemical bath occurs at atmospheric pressure and ambient temperature.
3 . The method of claim 1 , further comprising:
removing the self-assembled monolayer from the substrate;
bonding the dielectric material of the substrate to another substrate with surfaces covered by the dielectric material by contacting substrates together; and
annealing substrates to bond metal surfaces together.
4 . The method of claim 3 , further comprising:
removing the self-assembled monolayer using a plasma-based process for approximately 10 seconds to approximately 60 seconds.
5 . The method of claim 3 , wherein the substrate is a die.
6 . The method of claim 3 , wherein annealing occurs at a temperature of approximately 150 degrees Celsius.
7 . The method of claim 1 , wherein the chemical bath includes an alkanethiol.
8 . The method of claim 7 , wherein the alkanethiol has a linear structure or a benzene ring structure.
9 . The method of claim 1 , wherein the dielectric material is a high-k dielectric material.
10 . The method of claim 9 , wherein the high-k dielectric material is aluminum oxide or hafnium oxide.
11 . The method of claim 1 , wherein the substrate is immersed in the chemical bath for approximately 10 minutes to approximately 30 minutes.
12 . The method of claim 1 , wherein the metal surface is copper, silver, gold, palladium, platinum, cobalt, titanium, nickel, or combinations thereof.
13 . The method of claim 1 , wherein a thickness of the dielectric material is greater than zero nm to approximately 10 nm.
14 . A method for increasing dielectric bonding strength during wafer-level processing, comprising:
immersing a substrate into a chemical bath, wherein the chemical bath forms a self-assembled monolayer on at least one metal surface of the substrate and wherein immersing the substrate into the chemical bath occurs at atmospheric pressure and ambient temperature; and
selectively depositing a high-k dielectric material to form a dielectric cap on at least one dielectric surface of the substrate absent of the self-assembled monolayer, wherein a thickness of the high-k dielectric material is greater than zero nm to approximately 10 nm.
15 . The method of claim 14 , wherein the substrate is immersed in the chemical bath for approximately 10 minutes to approximately 30 minutes.
16 . The method of claim 14 , further comprising:
removing the self-assembled monolayer from the substrate;
bonding the high-k dielectric material of the substrate to another substrate with surfaces covered by the high-k dielectric material by contacting substrates together; and
annealing substrates to bond metal surfaces together.
17 . The method of claim 16 , further comprising:
removing the self-assembled monolayer using a plasma-based process for approximately 10 seconds to approximately 60 seconds.
18 . The method of claim 14 , wherein the chemical bath includes an alkanethiol with a linear structure or a benzene ring structure.
19 . The method of claim 14 , wherein the high-k dielectric material is aluminum oxide or hafnium oxide.
20 . A non-transitory, computer readable medium having instructions stored thereon that, when executed, cause a method for increasing dielectric bonding strength during wafer-level processing to be performed, the method comprising:
immersing a substrate into a chemical bath, wherein the chemical bath forms a self-assembled monolayer on at least one metal surface of the substrate and wherein immersing the substrate into the chemical bath occurs at atmospheric pressure and ambient temperature; and
selectively depositing a dielectric material to form a dielectric cap on at least one dielectric surface of the substrate absent of the self-assembled monolayer.