Method of forming bit line of semiconductor device
A method of forming a conductive structure (e.g., bit line) of a semiconductor device includes forming a barrier metal layer on a semiconductor substrate in which structures are formed. An amorphous titanium carbon nitride layer is formed on the barrier metal layer. A tungsten seed layer is formed on the amorphous titanium carbon nitride layer under an atmosphere including a boron gas. A tungsten layer is formed on the tungsten seed layer, thus forming a bit line.
1. A method for forming of a semiconductor device, the method comprising:
forming a barrier metal layer over a trench provided on a semiconductor substrate, the barrier metal layer being provided over surfaces of the trench;
forming an amorphous titanium carbon nitride layer over the barrier metal layer;
forming a tungsten seed layer over the amorphous titanium carbon nitride layer; and
forming a tungsten layer over the tungsten seed layer to form a conductive structure.
2. The method of claim 1 , wherein the tungsten seed layer is formed directly on the amorphous titanium carbon nitride layer, so that the amorphous titanium carbon nitride layer is used to control a seed number of the tungsten seed layer,
wherein the conductive structure is a bit line.
3. The method of claim 2 , wherein the tungsten seed layer is formed in an atmosphere including a boron gas to provide the tungsten seed layer with a big grain size.
4. The method of claim 3 , wherein the tungsten layer is formed directly on the tungsten seed layer, the tungsten layer having a crystalline state.
5. The method of claim 3 , wherein B 2 H 6 is used as a source of the boron gas.
6. The method of claim 1 , wherein the bit line has a resistivity of about 220 ohm/string.
7. The method of claim 1 , wherein the amorphous titanium nitride layer is formed to a thickness of about 10 Å to about 100 Å, wherein the conductive structure is a single damascene structure or a dual damascene structure.
8. The method of claim 1 , wherein the amorphous titanium nitride layer is formed using one of TDMAT (tetrakis dimethylamino titanium, Ti[N(CH 3 ) 2 ] 4 ) and TDEAT (tetrakis diethylamino titanium, Ti[N(C 2 H 5 ) 2 ] 4 ) as a precursor.
9. The method of claim 1 , wherein the tungsten seed layer is formed under an atmosphere including SiH 4 , WF 6 , and a boron gas.
10. The method of claim 1 , wherein the tungsten seed layer is formed to a thickness of about 10 Å to about 300 Å at a temperature of about 350° C. to about 550° C.
11. The method of claim 1 , wherein the tungsten seed layer is formed by an Atomic Layer Deposition (ALD) or Pulsed Nucleation Layer (PNL) method.
12. The method of claim 1 , further comprising, after the barrier metal layer is formed, performing a thermal treatment process to form an ohmic contact layer at the interface of the semiconductor substrate and the barrier metal layer.
13. The method of claim 12 , wherein the thermal treatment process employs a Rapid Thermal Treatment (RTA) process.
14. The method of claim 1 , wherein the barrier metal layer is formed using includes a Ti layer and a TiN layer.
15. A method of forming a bit line of a semiconductor device, the method comprising:
forming an interlayer insulating layer on a semiconductor substrate in which structures are formed, and etching the interlayer insulating layer to form a trench;
forming a barrier metal layer over the trench;
forming an amorphous titanium carbon nitride layer on the barrier metal layer;
forming a tungsten seed layer on the amorphous titanium carbon nitride layer under an atmosphere including a boron gas; and
forming a tungsten layer on the tungsten seed layer to from a bit line.
16. The method of claim 15 , wherein the amorphous titanium nitride layer is formed to a thickness of about 10 Å to about 100 Å.
17. The method of claim 15 , wherein the amorphous titanium nitride layer is formed using one of TDMAT (tetrakis dimethylamino titanium, Ti[N(CH 3 ) 2 ] 4 ) and TDEAT (tetrakis diethylamino titanium, Ti[N(C 2 H 5 ) 2 ] 4 ) as a precursor, wherein B 2 H 6 is used as a source of the boron gas.
18. The method of claim 15 , wherein the atmosphere includes SiH 4 and WF 6 , wherein the tungsten seed layer is formed to a thickness of about 10 Å to about 300 Å at a temperature of about 350° C. to about 550° C.,wherein the tungsten seed layer is formed by an Atomic Layer Deposition (ALD) or Pulsed Nucleation Layer (PNL) method.
19. A method for forming of a semiconductor device, the method comprising:
forming a barrier metal layer over a trench provided on a semiconductor substrate, the barrier metal layer being provided over surfaces of the trench;
forming an amorphous layer over the barrier metal layer, the amorphous layer including metal;
forming a conductive seed layer over the amorphous layer, the conductive seed layer having a given metal; and
forming a conductive layer over the tungsten seed layer to form a conductive structure, the conductive layer having the same given metal.
20. The method of claim 19 , wherein the conductive seed layer is formed directly on the amorphous layer, so that the amorphous layer is used to control a seed number of the conductive seed layer,
wherein the tungsten seed layer is formed in an atmosphere including a boron gas to provide the conductive seed layer with a big grain size, and
wherein the conductive structure is a single damascene structure or a dual damascene structure.
21. The method of claim 20 , wherein the conductive layer is formed directly on the tungsten seed layer, the tungsten layer having a crystalline state,
wherein B 2 H 6 is used as a source of the boron gas, and
wherein the conductive structure is a bit line.
22. The method of claim 19 , wherein the amorphous layer is the amorphous titanium carbon nitride layer, wherein the conductive seed layer and the conductive layer each includes tungsten.