Method for selective deposition of a thin self-assembled monolayer
View Patent ↗A method for selective deposition of self-assembled monolayers to the surface of a substrate for use as a diffusion barrier layer in interconnect structures is provided comprising the steps of depositing a first self-assembled monolayer to said surface, depositing a second self-assembled monolayer to the non-covered parts of said surface and subsequently heating said substrate to remove the first self-assembled monolayer. The method of selective deposition of self-assembled monolayers is applied for the use as diffusion barrier layers in a (dual) damascene structure for integrated circuits.
1. A semiconductor device, the device comprising a damascene copper interconnect structure and a self-assembled monolayer, wherein the damascene copper interconnect structure comprises exposed dielectric parts and exposed copper parts, and wherein the self assembled monolayer is selectively deposited exclusively onto the exposed dielectric parts by bonding through a head group, but is not deposited on the exposed copper parts of the damascene copper interconnect structure, wherein the self-assembled monolayer comprises a plurality of molecules of chemical formula (Z) 3 Si—R 3 —SH, wherein —R 3 — is an alkyl chain, wherein —SH is a terminal group, wherein the head group is —Si(Z) 3 , and wherein Z is independently selected from the group consisting of CH 3 , Cl, C 2 H 5 , OCH 3 , and OC 2 H 5 .
2. The semiconductor device of claim 1 , wherein the damascene copper interconnect structure is a dual damascene structure.
3. The semiconductor device of claim 1 , wherein said self-assembled monolayer comprises a plurality of molecules of chemical formula SH(CH 2 ) 10 SiCl 3 .
4. The semiconductor device of claim 1 , further comprising a direct copper-to-copper contact between copper at a bottom of a via and copper in a trench of an underlying level.
5. The semiconductor device of claim 1 , wherein R is an alkyl chain of n carbon atoms, and wherein n is an integer from 1 to 30.
6. The semiconductor device of claim 5 , wherein n is an integer from 1 to 18.
7. The semiconductor device of claim 6 , wherein n is an integer from 6 to 16.
8. The semiconductor device of claim 1 , wherein R 3 is an alkyl chain of formula —(CH 2 ) n —, wherein n is an integer of from 1 to 30.
9. The semiconductor device of claim 8 , wherein n is an integer from 1 to 18.
10. The semiconductor device of claim 9 , wherein n is an integer from 6 to 16.