Method of sequentially forming silicide layer and contact barrier in semiconductor integrated circuit device
A method of sequentially forming a silicide layer and a contact barrier in a semiconductor device is provided. In the method, a pre-metal dielectric layer is deposited over an underlying structure that has a silicon substrate, a gate electrode on the substrate, and source/drain regions in the substrate. Contact holes are formed toward the gate electrode and the source/drain regions in the dielectric layer. Then, a metal layer for the silicide layer is selectively deposited on the bottom of the contact holes by using ion implantation, for example. Thereafter, the contact barrier is conformally deposited on entire exposed surface, and a heat-treatment process is performed to form the silicide layer from the metal layer.
1 . A method of sequentially forming a silicide layer and a contact barrier in a semiconductor device, the method comprising:
depositing a pre-metal dielectric layer over an underlying structure having a silicon substrate, a gate electrode on the substrate, and source/drain regions in the substrate;
forming contact holes toward the gate electrode and the source/drain regions in the dielectric layer;
selectively depositing a metal layer on the bottom of the contact holes;
conformally depositing a contact barrier on entire exposed surface; and
performing a heat-treatment to form a silicide layer from the metal layer.
2 . The method of claim 1 , wherein the selective depositing of the metal layer uses ion implantation.
3 . The method of claim 2 , wherein the ion implantation is performed with high dose and low energy.
4 . The method of claim 1 , wherein the metal layer is formed of a metal selected from the group consisting of titanium (Ti), cobalt (Co), vanadium (V), chromium (Cr), zirconium (Zr), niobium (Nb), molybdenum (Mo), and hafnium (Hf).
5 . The method of claim 1 , wherein the contact barrier is formed of titanium (Ti) and titanium nitride (TiN).
6 . The method of claim 1 , wherein the heat-treatment is performed once only at a high temperature.
7 . The method of claim 1 , wherein the heat-treatment is performed twice, once at a low temperature and once at a high temperature.
8 . The method of claim 7 , wherein the heat-treatment is performed in an in-situ chamber.