Semiconductor devices and methods of manufacturing the same
A semiconductor device includes a metal pattern filling a trench formed through at least a portion of an insulating interlayer on a substrate and including copper, and a wetting improvement layer pattern in the metal pattern including at least one of tantalum, tantalum nitride, titanium, titanium nitride, ruthenium, cobalt and manganese.
1. A method of manufacturing a semiconductor device, comprising:
forming a trench on an insulating interlayer on a substrate;
forming a first seed layer on an inner wall of the trench and on the insulating interlayer, the first seed layer having a first thickness on an upper portion of the trench greater than a second thickness on a lower portion of the trench;
forming a preliminary metal layer filling the lower portion of the trench by performing a reflow process on the first seed layer;
forming a wetting improvement layer on a portion of the preliminary metal layer on the upper portion of the trench; and
forming a metal layer filling the trench by an electrolytic plating process.
2. The method of claim 1 , wherein the forming a metal layer includes performing the electrolytic plating process using an additive and an electrolyte, the additive having a suppressor, an accelerator and a leveler, and the electrolyte including a copper ion, and
wherein the forming a wetting improvement layer includes forming at least one of tantalum, tantalum nitride, titanium, titanium nitride, ruthenium, cobalt and manganese.
3. The method of claim 1 , further comprising:
forming a barrier layer on the inner wall of the trench and on the insulating interlayer prior to the forming a first seed layer.
4. The method of claim 1 , wherein the forming a first seed layer includes performing a sputtering process using copper as a target when a bias power is applied to the substrate.
5. The method of claim 1 , wherein the forming a preliminary metal layer exposes a portion of the inner wall of the trench, the method further comprising:
forming a second seed layer on the exposed portion of the inner wall of the trench.
6. The method of claim 4 , wherein the forming a wetting improvement layer forms the wetting improvement layer on the preliminary metal layer in the trench.
7. The method of claim 1 , further comprising:
reducing oxidized portions of the preliminary metal layer and the wetting improvement layer prior to the forming a metal layer.
8. The method of claim 1 , further comprising:
planarizing the metal layer until the insulating interlayer is exposed after the forming a metal layer,
wherein the wetting improvement layer on the upper portion of the trench is removed by the planarization of the metal layer.