What is claimed is:
1. A method for manufacturing a semiconductor device, the method comprising the steps of:
(a) forming a metal layer on a semiconductor substrate;
(b) oxidizing the metal layer at a first temperature so that an exposed surface of the metal layer is changed into a mixed phase of metal forming the metal layer and oxygen; and
(c) heating the metal layer having the mixed phase of metal and oxygen at a second temperature higher than the first temperature in an oxygen atmosphere, after the step (b).
2. The method as claimed in claim 1, wherein the metal layer is sufficiently oxidized in step (b) so that the metal layer having the mixed phase of metal and oxygen is substantially resistant to further oxidation during the heating of step (c).
3. The method as claimed in claim 1, wherein the step of oxidizing the metal layer includes the step of exposing the metal layer to a plasma including oxygen and substantially free of argon (Ar).
4. The method as claimed in claim 1, wherein the step of oxidizing the metal layer includes the step of exposing the metal layer to a plasma including oxygen.
5. The method as claimed in claim 4, wherein the metal layer is exposed to the plasma for sufficiently long so that the metal layer having the mixed phase of metal and oxygen is resistant to further oxidation during the heating of step (c).
6. The method as claimed in claim 4, wherein the metal layer is formed of a material selected from the group consisting of ruthenium (Ru), iridium (Ir), rhodium (Rh), palladium (Pd), osmium (Os), and any combination of Ru, Ir, Rh, Pd, and Os and the metal layer is exposed to the plasma for over about 200 seconds.
7. The method as claimed in claim 6, wherein the metal layer is exposed to the plasma for over about 300 seconds.
8. The method as claimed in claim 4, wherein the plasma including oxygen is selected from the group consisting of a mixture of helium (He) and oxygen, a mixture of N2 and oxygen, N2O, NO, NO2, and a mixture of more than one of N2O, NO, and NO2.
9. The method as claimed in claim 4, wherein the plasma including oxygen is substantially free of argon (Ar) and is selected from the group consisting of a mixture of helium (He) and oxygen, a mixture of N2 and oxygen, N2O, NO, NO2, and a mixture of more than one of N2O, NO, and NO2.
10. The method as claimed in claim 1, wherein the step of oxidizing the metal layer includes the step of ozone (O3) treating the metal layer.
11. The method as claimed in claim 1, wherein the step of oxidizing the metal layer includes the step of H2O treating the metal layer.
12. The method as claimed in claim 1, wherein the first temperature is selected to be sufficiently high and a time duration for oxidizing is selected to sufficiently long to sufficiently oxidize the metal layer so that the roughness of the upper surface of the metal layer is not substantially changed during the heating of step (c).
13. The method as claimed in claim 1, wherein the first temperature is selected to be sufficiently high and a time duration for oxidizing is selected to sufficiently long to sufficiently oxidize the metal layer to render it substantially resistant to further oxidation during the heating of step (c).
14. The method as claimed in claim 13, wherein the first temperature is selected to be sufficiently low and a time duration for the oxidizing step (b) is selected to sufficiently short so that the roughness of the upper surface of the metal layer is not substantially changed.
15. The method as claimed in claim 1, wherein the first temperature is sufficiently low to avoid changing the electrical properties of the interface between the metal layer and the semiconductor substrate.
16. The method as claimed in claim 1, wherein the second temperature is sufficiently high to change a predetermined electrical property of the interface between the metal layer and the semiconductor substrate.
17. The method as claimed in claim 1, wherein the first temperature is substantially below about 400 C. and the metal layer is formed of a material selected from the group consisting of ruthenium (Ru), iridium (Ir), rhodium (Rh), palladium (Pd), osmium (Os), and any combination of Ru, Ir, Rh, Pd, and Os.
18. The method as claimed in claim 17, wherein the first temperature is about 150 C.
19. The method as claimed in claim 17, wherein the second temperature is at least about 400 C.
20. The method as claimed in claim 17, wherein the second temperature is about 400 C.
21. The method as claimed in claim 1, wherein the metal layer is formed of a material selected from the group consisting of ruthenium (Ru), iridium (Ir), rhodium (Rh), palladium (Pd), osmium (Os), and any combination of Ru, Ir, Rh, Pd, and Os.
22. The method as claimed in claim 1, wherein the step of forming a metal layer is preceded by the step of forming a dielectric layer on the semiconductor substrate and the step of forming a metal layer comprises forming a metal layer on the dielectric layer.
23. The method as claimed in claim 22, wherein the metal layer is an upper electrode of a capacitor.
24. The method as claimed in claim 23, wherein the metal layer is formed of a material selected from the group consisting of ruthenium (Ru), iridium (Ir), rhodium (Rh), palladium (Pd), osmium (Os), and any combination of Ru, Ir, Rh, Pd, and Os.
25. The method as claimed in claim 24, wherein the dielectric layer is formed of a material selected from the group consisting of Ta2O5, SrTiO3 (STO), (Ba, Sr)TiO3 (BST), PbTiO3, Pb(Zr, Ti)O3 (PZT), SrBi2Ta2O5 (SBT), (Pb, La)(Zr, Ti)O3, Bi4Ti3O12, and BaTiO3 (BTO).
26. The method as claimed in claim 3, further comprising the steps of:
forming the metal layer from ruthenium (Ru);
exposing the metal layer to a plasma including nitrogen and oxygen at a temperature substantially less than about 400 C. for over about 200 seconds; and
heating the metal layer in an oxygen atmosphere at over about 400 C.
27. The method as claimed in claim 3, wherein the metal layer is formed of ruthenium (Ru), is exposed to a plasma including nitrogen and oxygen for over about 300 seconds and is heated in an oxygen atmosphere at over about 400 C.
28. A method for manufacturing an integrated circuit capacitor, the method comprising the steps of:
(a) forming a metal layer on a semiconductor substrate;
(b) oxidizing the metal layer at a first temperature so that an exposed surface of the metal layer is changed into a mixed phase of metal forming the metal layer and oxygen; and
(c) heating the metal layer having the mixed phase of metal and oxygen at a second temperature higher than the first temperature in an oxygen atmosphere, after the step (b).
29. The method as claimed in claim 28, wherein the metal layer is sufficiently oxidized in step (b) so that the metal layer having the mixed phase of metal and oxygen is substantially resistant to further oxidation during the heating of step (c).
30. The method as claimed in claim 29, wherein the first temperature is selected to be sufficiently high and a time duration for oxidizing is selected to sufficiently long to sufficiently oxidize the metal layer so that the roughness of the upper surface of the metal layer is not substantially changed during the heating of step (c).
31. The method as claimed in claim 29, wherein the first temperature is selected to be sufficiently high and a time duration for oxidizing is selected to sufficiently long to sufficiently oxidize the metal layer to render it substantially resistant to further oxidation during the heating of step (c).
32. The method as claimed in claim 29, wherein the first temperature is selected to be sufficiently low and a time duration for the oxidizing step (b) is selected to sufficiently short so that the roughness of the upper surface of the metal layer is not substantially changed.
33. The method as claimed in claim 29, wherein the first temperature is sufficiently low to avoid changing the electrical properties of the interface between the metal layer and the semiconductor substrate.
34. The method as claimed in claim 28, wherein the second temperature is sufficiently high to change a predetermined electrical property of the interface between the metal layer and the semiconductor substrate.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1.-16. (canceled)
17. A mixed catalyst system comprising:
(i) at least one polymerization catalyst comprising a Group 4 or Group 5 transition metal;
(ii) an activator;
(iii) at least one organochromium polymerization catalyst; and
(iv) a support material;
wherein, under polymerization conditions where the polymerization catalyst comprising a Group 4 or Group 5 transition metal is active, the organochromium polymerization catalyst has an activity at least 50% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal; and wherein, after contact with a molecular switch and under polymerization conditions, the organochromium polymerization catalyst has an activity at least 50% greater than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal.
18. The mixed catalyst system of claim 17, wherein the polymerization catalyst comprising a Group 4 or Group 5 transition metal comprises a transition metal selected from zirconium, hafnium, titanium, or vanadium.
19. The mixed catalyst system of claim 17, wherein the activator is an alumoxane.
20. The mixed catalyst system of claim 17, wherein the catalyst comprising a Group 4 or Group 5 transition metal comprises a metallocene represented by the formula:
LALBMXn;\u2003\u2003(i)
or
LAA*LBMXn;\u2003\u2003(ii)
where M is a Group 4 or 5 transition metal;
the ligands, LA and LB, are open, acyclic or fused ring(s) or ring system(s), including unsubstituted or substituted, cyclopentadienyl ligands, heteroatom substituted andor heteroatom containing cyclopentadienyl ligands;
each X is a leaving group;
A* is a bridging group; and
n is 0, 1, 2, or 3.
21. The mixed catalyst system of claim 17, wherein the organochromium polymerization catalyst is represented by the formula:
CrRn;\u2003\u2003(i)
where R is a C1 to C20 hydrocarbyl group; and
where n is selected from 2, 3, and 4;
or
CrLALB;\u2003\u2003(ii)
where LA and LB are independently selected from cyclopentadienyl, substituted cyclopentadienyl, indenyl, substituted indenyl, fluorenyl, or substituted fluorenyl; or
Cr(XRn)m;\u2003\u2003(iii)
where each X is, independently, N, O, P, or S, preferably N;
each n is independently 1 or 2;
m is 1 or 2; and
each R is, independently, an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group, provided at least one R group is an aryl or substituted aryl group.
22. A method of making a supported mixed catalyst system comprising:
(i) contacting a support material with a polymerization catalyst comprising a Group 4 or a Group 5 transition metal and an activator, such that the reactive groups on the support material are titrated, to form a supported polymerization catalyst;
(ii) thereafter contacting the supported polymerization catalyst with an organochromium polymerization catalyst to form a supported mixed catalyst system;
wherein the organochromium polymerization catalyst and polymerization catalyst comprising a Group 4 or Group 5 transition metal differ in molecular switch response by at least 50%; and
wherein the organochromium polymerization catalyst of the supported mixed catalyst system is less active than the polymerization catalyst comprising a Group 4 or Group 5 transition metal by at least 50%, under polymerization conditions where the polymerization catalyst comprising a Group 4 or Group 5 transition metal is active.
23. The method of claim 22, wherein the polymerization catalyst comprising a Group 4 or Group 5 transition metal comprises a transition metal selected from zirconium, hafnium, titanium, or vanadium.
24. The method of claim 22, wherein the catalyst comprising a Group 4 or Group 5 transition metal comprises a metallocene represented by the formula:
LALBMXn;\u2003\u2003(i)
or
LAA*LBMXn;\u2003\u2003(ii)
where M is a Group 4 or 5 transition metal;
the ligands, LA and LB, are open, acyclic or fused ring(s) or ring system(s), including unsubstituted or substituted, cyclopentadienyl ligands, heteroatom substituted andor heteroatom containing cyclopentadienyl ligands;
each X is a leaving group;
A* is a bridging group; and
n is 0, 1, 2, or 3.
25. The method of claim 22, wherein the activator is an alumoxane.
26. The method of claim 22, wherein the organochromium polymerization catalyst is represented by the formula:
CrRn;\u2003\u2003(i)
where R is a C1 to C20 hydrocarbyl group; and
where n is selected from 2, 3, and 4;
or
CrLALB;\u2003\u2003(ii)
where LA and LB are independently selected from cyclopentadienyl, substituted cyclopentadienyl, indenyl, substituted indenyl, fluorenyl, or substituted fluorenyl;
or
Cr(XRn)m;\u2003\u2003(iii)
where each X is, independently, N, O, P, or S, preferably N;
each n is independently 1 or 2;
m is 1 or 2; and
each R is, independently, an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group, provided at least one R group is an aryl or substituted aryl group.
27. The mixed catalyst system of claim 17, wherein the molecular switch comprises oxygen and an alkyl aluminum compound.
28. The mixed catalyst system of claim 17, wherein the polymerization catalyst comprising a Group 4 or Group 5 transition metal has a negative molecular switch response and the organochromium polymerization catalyst has a positive molecular switch response.
29. The mixed catalyst system of claim 27, wherein the alkyl aluminum compound is represented by the formula: AlR3 or AlR2H, wherein each R is, independently, a hydrocarbyl radical comprising from 2 to 10 carbon atoms, or a halide.
30. The mixed catalyst system of claim 17, wherein the molecular switch comprises oxygen in the form of air.
31. The method of claim 22, wherein the polymerization catalyst comprising a Group 4 or Group 5 transition metal has a negative molecular switch response and the organochromium polymerization catalyst has a positive molecular switch response.
32. The method of claim 22, wherein the molecular switch comprises oxygen and an alkyl aluminum compound.
33. The method of claim 32, wherein the alkyl aluminum compound is represented by the formula: AlR3 or AlR2H, wherein each R is, independently, a hydrocarbyl radical comprising from 2 to 10 carbon atoms, or a halide.
34. The method of claim 22, wherein the molecular switch comprises oxygen in the form of air.
35. The method of claim 22, wherein the weight ratio of the polymerization catalyst comprising a Group 4 or a Group 5 transition metal to the solid support material is in the range of from about 10:1 to about 0.0001:1 and where the weight ratio of the support material to the activator compound is in the range of from about 1:10 to about 100:1 such that the reactive groups on the support material are titrated.
36. The method of claim 35, wherein the contacting of step (i) is for a time period of from about 0.5 to about 24 hours.
37. The method of claim 36, wherein the contacting of step (i) occurs at a temperature of from between about 10\xb0 C. to about 200\xb0 C.
38. The method of claim 37, wherein the mixture is not heated during the contacting time.
39. The method of claim 37, wherein the contacting of step (ii) is for a time period of from about 0.5 hours to about 24 hours.
40. The method of claim 39, wherein the contacting of step (ii) is at a temperature from between about 20\xb0 C. to about 95\xb0 C.
41. The method of claim 40, wherein the mixture is not heated during the contacting time.
42. The mixed catalyst system of claim 17, wherein the organo chromium polymerization catalyst has an activity at least 60% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
43. The mixed catalyst system of claim 17, wherein the organo chromium polymerization catalyst has an activity at least 70% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
44. The mixed catalyst system of claim 17, wherein the organo chromium polymerization catalyst has an activity at least 80% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
45. The mixed catalyst system of claim 17, wherein the organo chromium polymerization catalyst has an activity at least 90% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
46. The mixed catalyst system of claim 17, wherein the organo chromium polymerization catalyst has an activity at least 98% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
47. The mixed catalyst system of claim 17, wherein after contact with the molecular switch the organo chromium polymerization catalyst has an activity at least 60% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
48. The mixed catalyst system of claim 17, wherein after contact with the molecular switch the organo chromium polymerization catalyst has an activity at least 70% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
49. The mixed catalyst system of claim 17, wherein after contact with the molecular switch the organo chromium polymerization catalyst has an activity at least 80% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
50. The mixed catalyst system of claim 17, wherein after contact with the molecular switch the organo chromium polymerization catalyst has an activity at least 90% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
51. The mixed catalyst system of claim 17, wherein after contact with the molecular switch the organo chromium polymerization catalyst has an activity at least 980% less than the activity of the polymerization catalyst comprising a Group 4 or Group 5 transition metal before contact with the molecular switch.
52. The mixed catalyst system of claim 17, further comprising a molecular switch.
53. The mixed catalyst system of claim 17, wherein the activator is a non-coordinating anion.