Levelers for copper deposition in microelectronics
View Patent ↗A composition for electrolytic plating in microelectronics which contains a leveler that comprises the reaction product of an aliphatic di(t-amine) with an alkylating agent. Electrolytic plating methods employing the leveler, a method for making the leveler, and the leveler compound.
1. An aqueous electrolytic composition useful in filling submicron features of a semiconductor integrated circuit device or through silicon vias,
the composition comprising:
an acid;
copper ions; and
a leveler that comprises an oligomer and/or polymer compound comprising salts comprising a cation having a structure:
wherein:
G is selected from the group consisting of a single covalent bond, —O—, —O-((A) r -O) s — and -((A) r -O) s —
A has the structure,
B has the structure,
D has the structure,
each of p, r, t, u, w, and y is an integer between 1 and 6 inclusive, each of q, v, x, k, and z is independently an integer between 0 and 6 inclusive, s is an integer between 1 and 10 inclusive, k is at least one when v or x is other than 0, q is at least one when G is other than a single covalent bond, at least one of v or z is at least one when G is a single covalent bond,
each of R 1 to R 6 , R 9 to R 19 , R 23 , R 25 and R 34 is independently selected from the group consisting of hydrogen or lower alkyl comprising 1 to 4 carbon atoms, each of R 7 , R 8 , R 20 , R 21 , R 22 , R 24 and R 33 is independently selected from the group consisting of substituted or unsubstituted aliphatic hydrocarbyl having 1 to 4 carbon atoms, and n is between 1 and 30;
provided that, when prepared by reaction of an alkylated agent of structure (I)
with an amine compound of structure (II)
in which R 13 is hydrogen said leveler may comprise or consist of polymer or oligomer chains that correspond to structure (III) except that R 13 is displaced in some or all repeat units by reaction with the structure (I) alkylating agent through which said polymer or oligomer-chains are cross-linked.
2. The composition as set forth in claim 1 wherein G is —O—, —O-((A) r -O) s — or -((A) r -O) s —.
3. The composition as set forth in claim 2 wherein s is at least two.
4. The composition as set forth in claim 3 wherein R 7 , R 8 , R 20 , R 21 , R 33 , and R 33 are methyl.
5. The composition as set forth in claim 1 wherein R 13 is alkyl.
6. The composition as set forth in claim 1 wherein x is at least one.
7. The composition as set forth in claim 1 wherein each of R 7 , R 8 , R 13 , R 20 , R 21 , R 23 , and R 33 is methyl.
8. The composition as set forth in claim 1 wherein said leveler comprises an oligomer or polymer compound selected from the group consisting of
9. The composition as set forth in claim 1 wherein the leveler has an average molecular weight between about 1000 and about 5000.