Method of manufacturing a semiconductor device
View Patent ↗To provide a technique capable of improving the reliability of a semiconductor element and its product yield by reducing the variations in the electrical characteristic of a metal silicide layer. After forming a nickel-platinum alloy film over a semiconductor substrate 1 , by carrying out a first thermal treatment at a thermal treatment temperature of 210 to 310° C. using a heater heating device, the technique causes the nickel-platinum alloy film and silicon to react with each other to form a platinum-added nickel silicide layer in a (PtNi) 2 Si phase. Subsequently, after removing the unreacted nickel-platinum alloy film, the technique carries out a second thermal treatment having the thermal treatment temperature higher than that of the first thermal treatment to form the platinum-added nickel silicide layer in a PtNiSi phase. The temperature rise rate of the first thermal treatment is set to 10° C./s or more (for example, 30 to 250° C./s) and the temperature rise rate of the second thermal treatment is set to 10° C./s or more (for example, 10 to 250° C./s).
1. A method of manufacturing a semiconductor device, comprising the steps of:
(a) preparing a semiconductor substrate made of single crystal silicon;
(b) forming a semiconductor region over the semiconductor substrate;
(c) forming an alloy film of nickel and platinum over the semiconductor substrate including the semiconductor region;
(d) forming a platinum-added nickel silicide layer in a (PtNi)2Si phase by carrying out a first thermal treatment to cause the alloy film and the semiconductor region to react with each other;
(e) after step (d), removing the unreacted alloy film over the platinum-added nickel silicide layer in the (PtNi)2Si phase over the semiconductor region; and
(f) after step (e), carrying out a second thermal treatment with the thermal treatment temperature higher than that of the first thermal treatment to form the platinum-added nickel silicide layer in a PtNiSi phase,
wherein a temperature rise rate of the first thermal treatment in step (d) is 30 to 250° C./s,
wherein a temperature rise rate of the second thermal treatment in step (f) is 10° C./s or more,
wherein a heater heating method is used for the first thermal treatment in step (d), and
wherein the second thermal treatment in step (f) is a spike anneal process.
2. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the temperature of the first thermal treatment in step (d) is 210 to 310° C.
3. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the temperature rise rate of the second thermal treatment in step (f) is 10 to 250° C./s.
4. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the second thermal treatment in step (f) is a soak anneal process.
5. The method of manufacturing a semiconductor device according to claim 4 ,
wherein the thermal treatment temperature of the second thermal treatment in step (f) is 380 to 495° C./s.
6. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the thermal treatment temperature of the second thermal treatment in step (f) is 380 to 525° C./s.
7. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the first thermal treatment in step (d) is carried out in an inert gas having a thermal conductivity higher than that of a nitrogen gas or in a gas atmosphere that is the nitrogen gas added with a gas having the thermal conductivity higher than that of the nitrogen gas.
8. The method of manufacturing a semiconductor device according to claim 7 ,
wherein the inert gas is helium or neon.
9. The method of manufacturing a semiconductor device according to claim 1 ,
wherein a heater heating method or a lamp heating method is used for the second thermal treatment in step (f).
10. The method of manufacturing a semiconductor device according to claim 9 ,
wherein the second thermal treatment in step (f) is carried out in an inert gas having the thermal conductivity higher than that of a nitrogen gas or in a gas atmosphere that is the nitrogen gas added with a gas having the thermal conductivity higher than that of the nitrogen gas.
11. The method of manufacturing a semiconductor device according to claim 10 ,
wherein the inert gas is helium or neon.
12. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the semiconductor region is a semiconductor region for a source or drain.
13. The method of manufacturing a semiconductor device according to claim 12 , further comprising the steps of:
(a1) after step (a), forming a gate insulating film over the semiconductor substrate; and
(a2) forming a gate electrode made of polycrystalline silicon over the gate insulating film,
wherein, in step (c), the alloy film is formed over the semiconductor substrate including the semiconductor region so as to cover the gate electrode.
14. The method of manufacturing a semiconductor device according to claim 1 , further comprising the step of:
(c1) after step (c) and before step (d), forming a barrier film over the alloy film,
wherein, in step (e), the barrier film and the unreacted alloy film are removed.
15. The method of manufacturing a semiconductor device according to claim 1 ,
wherein the barrier film does not react with the alloy film even if the first thermal treatment is carried out.
16. The method of manufacturing a semiconductor device according to claim 1 , further comprising the step of:
(c2) before step (c), dry-cleaning a surface of the semiconductor region in a main surface of the semiconductor substrate,
wherein, after step (c2), step (c) is carried out without exposing the semiconductor substrate to air.