Semiconductor device with a metal line and method of forming the same
View Patent ↗A method of forming a metal line in a semiconductor device including forming an inter-metal dielectric (IMD) layer on the semiconductor substrate including the predetermined pattern, planarizing the IMD layer through a first CMP process, and patterning a via hole on the planarized substrate. The method further includes depositing a barrier metal layer in the via hole, filling a refractory metal in an upper part of the barrier metal layer, planarizing the substrate filled with the refractory metal by performing a second CMP process, forming a refractory metal oxide layer by oxidizing a residual refractory metal region created by the second CMP process, and forming a refractory metal plug by removing the refractory metal oxide layer through a third CMP process.
1. A method of forming a metal line in a semiconductor device, comprising:
filling a substrate including a predetermined pattern with a refractory metal;
planarizing the substrate filled with the refractory metal by performing a chemical mechanical planarization (CMP) process;
forming a refractory metal oxide layer by oxidizing a residual refractory metal region created by the CMP process; and
forming a refractory metal plug by removing the refractory metal oxide layer.
2. The method of claim 1 , wherein the filling of the substrate with the refractory metal comprises:
forming an inter-metal dielectric (IMD) layer on the semiconductor substrate including the predetermined pattern;
planarizing the IMD layer through a CMP process;
patterning a via hole on the planarized substrate;
depositing a barrier metal layer in the via hole; and
filling the refractory metal on the barrier metal layer.
3. The method of claim 1 , wherein the refractory metal is tungsten.
4. The method of claim 1 , wherein the refractory metal oxide layer includes an oxide layer in which an oxidized refractory metal fills both a surface and an inside thereof.
5. The method of claim 1 , wherein the refractory metal oxide layer is formed by oxidizing the residual refractory metal region through an electroless plating method.
6. The method of claim 1 , wherein the removal of the refractory metal oxide layer is performed by a CMP process.
7. A semiconductor device with a metal line, comprising:
an inter-metal dielectric (IMD) layer formed on a semiconductor substrate including a predetermined pattern;
a via hole which is patterned on the substrate after planarizing the IMD layer;
a barrier metal layer deposited at an inside of the via hole;
a refractory metal layer formed on the barrier metal layer;
a refractory metal oxide layer formed by oxidizing a residual refractory metal that is left after planarizing the refractory metal layer; and
a refractory metal plug formed by removing the refractory metal oxide layer.
8. The semiconductor device of claim 7 , wherein the refractory metal is tungsten.
9. The semiconductor device of claim 7 , wherein the refractory metal oxide layer includes an oxide layer in which an oxidized refractory metal fills both a surface and an inside thereof.
10. The semiconductor device of claim 7 , wherein the refractory metal oxide layer is formed by oxidizing the residual refractory metal through an electroless plating method.
11. The semiconductor device of claim 7 , wherein the removal of the refractory metal oxide layer is performed by a chemical mechanical planarization (CMP) process.