CN102760758A - Metal gate structure - Google Patents
Metal gate structure Download PDFInfo
- Publication number
- CN102760758A CN102760758A CN201110104782XA CN201110104782A CN102760758A CN 102760758 A CN102760758 A CN 102760758A CN 201110104782X A CN201110104782X A CN 201110104782XA CN 201110104782 A CN201110104782 A CN 201110104782A CN 102760758 A CN102760758 A CN 102760758A
- Authority
- CN
- China
- Prior art keywords
- layer
- nitrogen
- caught
- workfunction layers
- nitrogenous
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Insulated Gate Type Field-Effect Transistor (AREA)
- Electrodes Of Semiconductors (AREA)
Abstract
The invention discloses a metal gate structure. The metal gate structure comprises a high-dielectric constant gate dielectric layer, a nitrogen-containing layer, a power function metal layer and a nitrogen trap layer. The nitrogen-containing layer is arranged between the power function metal layer and the high-dielectric constant gate dielectric layer; the nitrogen trap layer is arranged between the power function metal layer and the high-dielectric constant gate dielectric layer; and the nitrogen trap layer does not contain any nitrogen ion or low-concentration nitrogen ion.
Description
Technical field
The present invention relates to a kind of metal gate structure, refer to a kind of n type metal gates electrode structure especially.
Background technology
Along with the semiconductor element size continues micro; Utilize in the conventional method and reduce gate dielectric; For example reduce the silicon dioxide layer thickness, to reach the method for optimization purpose, the tunneling effect (tunneling effect) that faces because of electronics causes the excessive physical restriction of leakage current.For the effectively generation evolution of extension logic element; High-k (being designated hereinafter simply as high-K) material can effectively reduce physics limit thickness because of having; And at identical equivalent oxide thickness (equivalent oxide thickness; Be designated hereinafter simply as EOT) under, effectively reduce leakage current and reach equivalent capacity, and be used to replace traditional silicon dioxide layer or silicon oxynitride layer as gate dielectric with advantage such as control channel switches etc.
Traditional grid material polysilicon then faces boron penetration (boron penetration) effect, causes problems such as element efficiency reduction; And polysilicon gate more meets with the consumption effect layer (depletioneffect) that is difficult to avoid, and makes that the gate dielectric layer thickness of equivalence increases, the grid capacitance value descends, and then causes the predicaments such as decline of element drives ability.To this problem; The semiconductor industry more proposes with new grid material; For example utilize metal gates to replace traditional polysilicon gate, in order to control electrode as coupling high-k (High-K) gate dielectric with work function (work function) metal level.
Yet; Even utilize high-k (high-K) gate dielectric to replace traditional silicon dioxide or silicon oxynitride gate dielectric; And replace traditional polysilicon gate with metal gates with coupling work function, how to increase semiconductor element usefulness constantly and guarantee the problem that its reliability still solves for semiconductor dealer institute desire.
Summary of the invention
Therefore, one of the present invention purpose is to provide a kind of metal gate structure with preferred element performance and reliability.
According to claim provided by the present invention; A kind of metal gate structure is provided, and this metal gate structure includes high-k (high-K) gate dielectric, nitrogenous (N-containing) layer, workfunction layers and nitrogen and catches sunken (N-trapping) layer.This nitrogenous layer is arranged between this workfunction layers and this high dielectric constant gate dielectric layer; And this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this high-k (high-K) gate dielectric, and this nitrogen is caught to fall into and layer do not comprised any nitrogen ion.
According to claim provided by the present invention, other provides a kind of metal gate structure, and this metal gate structure includes high-k (high-K) gate dielectric, nitrogenous layer, workfunction layers and nitrogen and catches sunken layer.This nitrogenous layer is arranged between this workfunction layers and this high dielectric constant gate dielectric layer; And this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this high dielectric constant gate dielectric layer, and this nitrogen is caught to fall into and layer comprised the NITROGEN IN LOW CONCENTRATION ion.
According to metal gate structure provided by the present invention, utilize the nitrogen of complete nonnitrogenous ion to catch to fall into layer and catch the nitrogen ion in the nitrogenous layer, with the metal ion diffusion rate that increases workfunction layers and improve its diffusion result.Therefore; After the adjustment of accomplishing workfunction metal; Nitrogen is caught and is fallen into layer and can capture the nitrogen ion in the nitrogenous layer and comprise the NITROGEN IN LOW CONCENTRATION ion, and the diffusivity of metal is raised and reaches the purpose of the work function of adjustment (tuning) metal gates to 3.9～4.3 electron-volts (eV) expecting in the workfunction layers.In view of the above, the present invention provides the metal gate structure that has than high-reliability.
Description of drawings
Fig. 1 to Fig. 2 is the sketch map of first preferred embodiment of metal gate structure provided by the present invention.
Fig. 3 is the sketch map of the change type of first preferred embodiment.
Fig. 4 is the sketch map of second preferred embodiment of metal gate structure provided by the present invention.
Fig. 5 and Fig. 6 are respectively the sketch map of the change type that is second preferred embodiment.
Fig. 7 to Fig. 8 is respectively the 3rd preferred embodiment of metal gate structure provided by the present invention and the sketch map of change type thereof.
Description of reference numerals
100,200,300 substrates
102,202,302 shallow-channel insulations
110,210,310 semiconductor elements
112,212,312 lightly doped drains
114,214,314 clearance walls
116,216,316 source/drains
118,218,318 metal silicides
120 gate trenchs
120a, 120b, 220a, 220b, 320a, 320b metal gates
122,222,322 high dielectric constant gate dielectric layers
124,224,324 nitrogenous layers
124a, 224a, 324a titanium nitride layer
124b, 224b, 324b tantalum nitride layer
126,226,326 nitrogen are caught and are fallen into layer
128,228,328 workfunction layers
130,230,330 top barrier layers
132,232,332 Low ESR metal levels
140,240,340 contact hole etching stopping layers
142,242,342 inner layer dielectric layers
Embodiment
See also Fig. 1 to Fig. 2, Fig. 1 to Fig. 2 is the sketch map of first preferred embodiment of metal gate structure provided by the present invention, and this preferred embodiment is to adopt back grid (gate-last) technology.As shown in Figure 1; Substrate 100 at first is provided, like silicon base, contain silicon base or silicon-coated insulated (silicon-on-insulator, SOI) substrate etc.; And be formed with a plurality of shallow-channel insulation (shallowtrench isolation, STI) 102 in the substrate 100 in order to electrical isolation to be provided.Next in substrate 100, form semiconductor element 110 at least.Semiconductor element 110 comprises metal gates 120a, lightly doped drain (light doped drain, LDD) 112 that are arranged in the gate trench 120.Because the semiconductor element 110 that this preferred embodiment provided is the n type semiconductor elements, so lightly doped drain (LDD) 112 is a n type lightly doped drain (LDD).And the sidewall around the metal gates 120a of semiconductor element 110 still comprises clearance wall 114; Clearance wall 114 is preferably the structure of composite film.Semiconductor element 110 also comprises n type source/drain 116, with the metal silicide 118 in order to the resistance that reduces contact interface.In this preferred embodiment, (selective epitaxial growth, SEG) method is made source/drain 116 to selective epitaxial growth also capable of using.As previously mentioned, because the semiconductor element 110 in this preferred embodiment is the n type semiconductor elements, so the epitaxial loayer manufacturing n type source/drain 116 that includes carborundum (SiC) capable of using.And in semiconductor element 110 and substrate 100, be formed with in regular turn contact hole etching stopping layer (contact etch stop layer, CESL) 140 with internal layer dielectric (inter-layer dielectric, ILD) layer 142.The step of elements such as above-mentioned formation metal gates 120a, lightly doped drain (LDD) 112, clearance wall 114, source/drain 116, metal silicide 118, contact hole etching stopping layer (CESL) 140 and internal layer dielectric (ILD) layer 142 is known by those of ordinary skill in this field, so repeat no more in this.
Please continue to consult Fig. 1.According to this first preferred embodiment; Comprising in regular turn in the metal gates 120a that gate dielectric 122, nitrogenous layer 124, nitrogen are caught falls into layer 126, workfunction layers 128, top resistance barrier (topbarrier) layer 130 and Low ESR metal (low-resistance metal) layer 132; These retes are from bottom to top to be stacked in regular turn in the gate trench 120, and Low ESR metal level 132 fills up gate trench 120.Low ESR metal level 132 can be and comprises that (aluminum A1), but is not limited thereto aluminium.Top barrier layer 130 can comprise that (titanium nitride TiN), but also is not limited thereto titanium nitride, and any barrier Low ESR metal level 132 that can successfully hinder all is applicable to as top barrier layer 130 with the material that lower metal reacts.128 of workfunction layers can comprise titanium aluminide single layer structure, Titanium Trialuminum (titanium tri-aluminide, TiAl3) single layer structure or aluminium/titanium double-decker.Nitrogenous layer 124 can comprise that (tantalum nitride TaN) or its combination, comprises the for example double-decker of TiN layer 124a and TaN layer 124b but be preferably, but is not limited thereto for TiN, tantalum nitride.And the TiN layer 124a in the nitrogenous layer 124 is as bottom resistance barrier (bottom barrier) layer, and TaN layer 124b then stops (etch stop) layer as etching.In addition, the bottom of metal gates 120a also can comprise dielectric layer (interfacial layer) (figure does not show), is formed at before the gate dielectric 122.
In addition, because this preferred embodiment and first gate dielectric (high-K first) process integration, so gate dielectric 122 comprises high-k (high-K) gate dielectric 122, and it can be selected from and comprise hafnium oxide (hafnium oxide, HfO
2), hafnium silicate oxygen compound (hafnium silicon oxide, HfSiO
4), the hafnium silicate oxynitrides (hafnium silicon oxynitride, HfSiON), aluminium oxide (aluminumoxide, Al
2O
3), lanthana (lanthanum oxide, La
2O
3), tantalum oxide (tantalum oxide, Ta
2O
5), yittrium oxide (yttrium oxide, Y
2O
3), zirconia (zirconium oxide, ZrO
2), strontium titanates (strontiumtitanate oxide, SrTiO
3), zirconium silicate oxygen compound (zirconium silicon oxide, ZrSiO
4), with zirconic acid hafnium (hafnium zirconium oxide, HfZrO
4) group that formed.
It should be noted that this preferred embodiment provides nitrogen to catch to fall into layer 126 between nitrogenous layer 124 and workfunction layers 128, its thickness between 10 dusts (angstrom) to 70 dusts.Nitrogen is caught and is fallen into layer 126 and do not comprise any nitrogen ion, and nitrogen catch fall into layer 126 be selected from titanium (titanium, Ti), tantalum (tantalum; Ta), lanthanum (lanthanum, La), yttrium (yttrium, Y), hafnium (hafnium; Hf), niobium (niobium; Nb), zirconium (zirconium, Zr) and vanadium (vanadium, the group that V) is formed.Those of ordinary skill should be known in this field; When the work function of adjustment metal gates, the aluminium ion in the workfunction layers 128 can be adjusted the work function of n type metal gates utmost point 120a via the interface that diffuses into high-k (high-K) gate dielectric 122 and nitrogenous layer 124.At this moment, the nitrogen that this preferred embodiment provided is caught and fallen into layer 126 is in order to catching the nitrogen ion in the nitrogenous layer 124 of below, with the resistance barrier effect that reduces nitrogenous layer 124, increase aluminum ions diffusion rate and improve aluminum ions diffusion result.
See also Fig. 2.Therefore, after the work function of adjusting metal gates 120a, the nitrogen of complete nonnitrogenous ion is caught sunken layer and is caught next NITROGEN IN LOW CONCENTRATION ion 126 interior can comprising by nitrogenous layer 124 originally.And at process flatening process such as chemico-mechanical polishing (chemical mechanical polishing; CMP) technology removes unnecessary Low ESR metal level 132, top barrier layer 130, workfunction layers 128, nitrogen and catches and fall into after layer 126 and the TaN layer 124b; Acquisition has the metal gates 120a of theoretical work function, and TaN layer 124b, nitrogen among the metal gates 120a are caught and fallen into layer 126, workfunction layers 128, has U type shape as shown in Figure 2 with the cross-section structure of top barrier layer 130.
In addition, see also Fig. 3, Fig. 3 is the sketch map of the change type of first preferred embodiment.Metal gates 120b that this change type provided and back gate dielectric (high-K last) process integration, and nitrogen is caught and is fallen into layer 128 and still be arranged between workfunction layers 128 and this nitrogenous layer 124.That is to say; After forming gate trench 120; Substrate 100 or dielectric layer (figure do not show) are exposed to gate trench 120 bottoms, just in gate trench 120, form in regular turn subsequently high-k (high-K) gate dielectric 122, nitrogenous layer 124, nitrogen catch fall into layer 126, workfunction layers 128, top barrier layer 130, with Low ESR metal level 132.Therefore; After chemico-mechanical polishing (CMP) technology removed unnecessary rete, high-k (high-K) gate dielectric 122 among the metal gates 120b that this change type provided, nitrogenous layer 124, nitrogen caught that the cross-section structure that falls into layer 126, workfunction layers 128, top barrier layer 130 is as shown in Figure 3 all to have a U type shape.
According to first preferred embodiment provided by the present invention; The nitrogen that complete nonnitrogenous ion is set between workfunction layers 128 in metal gate structure 120a/120b and the nitrogenous layer 124 is caught sunken layer 126; And the nitrogen that utilizes nonnitrogenous ion catches and falls into layer 126 and catch in the nitrogenous layers 124 nitrogen ion, with the resistance barrier effect that reduces nitrogenous layer 124, increase the metal ion diffusion rate of workfunction layers 128 and improve its diffusion result.Therefore accomplish after the adjustment of metal gates 120a/120b; Nitrogen in the metal gates 120a/20b is caught sunken layer 126 and can be captured the nitrogen ion in the nitrogenous layer 124 and comprise the NITROGEN IN LOW CONCENTRATION ion; And the diffusivity of metal is raised in the workfunction layers 128, makes the work function of metal gates 120a/120b be adjusted to 3.9～4.3eV of expection.
See also Fig. 4 to Fig. 5; Fig. 4 to Fig. 5 is respectively second preferred embodiment of metal gate structure provided by the present invention and the sketch map of change type thereof; And second preferred embodiment also adopts the back grid technology; In addition in second preferred embodiment with first its material of preferred embodiment components identical with the configuration can directly go the reference first preferred embodiment disclose, so repeat no more in this.As shown in Figure 4, substrate 200 at first is provided, and is formed with a plurality of shallow-channel insulations (STI) 202 in the substrate 200 in order to electrical isolation to be provided.Form semiconductor element 210 at least in the substrate 200.Semiconductor element 210 comprises metal gates 220a, lightly doped drain (LDD) 212.Because the semiconductor element 210 that this preferred embodiment provided also is the n type semiconductor elements, so lightly doped drain (LDD) 212 is a n type lightly doped drain (LDD).And the sidewall around the metal gates 220a of semiconductor element 210 still comprises clearance wall 214; Clearance wall 214 is preferably the structure of composite film.Semiconductor element 210 also comprises n type source/drain 216, with the metal silicide 218 in order to the resistance that reduces contact interface.In this preferred embodiment, also can integrate the epitaxial loayer manufacturing n type source/drain 216 that the utilization of selective epitaxial growth (SEG) method includes SiC.Contact hole etching stopping layer (CESL) 240 and internal layer dielectric (ILD) layer 242 and in semiconductor element 210 and substrate 200, be formed with in regular turn.
Please continue to consult Fig. 4.According to this preferred embodiment can with first gate dielectric (high-K first) process integration; Comprise in regular turn in the metal gates 220a gate dielectric 222, nitrogenous layer 224, nitrogen catch fall into layer 226, workfunction layers 228, top barrier layer 230, with Low ESR metal level 232; These retes are in the gate trench (figure does not show) that from bottom to top is stacked in metal gates 220a in regular turn, and Low ESR metal level 232 fills up the gate trench of metal gates 220a.It should be noted that; Nitrogenous layer 224 is the double-decker that comprises TiN layer 224a and TaN layer 224b in this preferred embodiment; Wherein TiN layer 224a is as bottom barrier layer; TaN layer 224b be then as etching stopping layer, and nitrogen catches and fall into layer 226 and be located in this double-decker, just between TiN layer 224a and the TaN layer 224b.In addition, the bottom of metal gates 220a also can comprise dielectric layer (figure does not show), is formed at before the gate dielectric 222.
It should be noted that this preferred embodiment provides nitrogen to catch in the double-decker of nitrogenous layer 224 and falls into layer 226, its thickness is between 10 dust to 70 dusts.Nitrogen is caught and is fallen into layer 226 and do not comprise any nitrogen ion, and nitrogen is caught and fallen into layer 226 and be selected from the group that Ti, Ta, La, Y, Hf, Nb, Zr and V form.Therefore when the work function of adjustment metal gates 220a, the aluminium ion in the workfunction layers 228 can be adjusted the work function of n type metal gates utmost point 220a via the interface that diffuses into high-k (high-K) gate dielectric 222 and nitrogenous layer 224.At this moment; Even the nitrogen that this preferred embodiment provided is caught and fallen into layer 226 is in order to catch nitrogen ion oxonium ion or the carbon ion in the upper and lower nitrogenous layer 224; Not only reduce the resistance barrier effect of upper and lower nitrogenous layer 224, and increase aluminum ions diffusion rate and improve aluminum ions diffusion result; Also can cause conduction band edge migration (conduction band edge shift), cause fermi level (Fermi level) to descend, and help the transistorized electrical performance of n type metal oxide semiconductor (nMOS).
Please continue to consult Fig. 4.Therefore, after the work function of adjusting metal gates 220a, the nitrogen of complete nonnitrogenous ion is caught sunken layer and is caught next NITROGEN IN LOW CONCENTRATION ion 226 interior can comprising by nitrogenous layer 224 originally.And remove unnecessary Low ESR metal level 232, top barrier layer 230, workfunction layers 228 and TaN layer 224b through flatening process such as chemico-mechanical polishing (CMP) technology after; Obtain the metal gates 220a with theoretical work function as shown in Figure 4, and the cross-section structure of the TaN layer 224b among the metal gates 220a, workfunction layers 228 and top barrier layer 230 has U type shape as shown in Figure 4.See also Fig. 5 in addition, Fig. 5 is the sketch map of the change type of second preferred embodiment.In this change type, the nitrogen among the metal gates 220a is caught the cross-section structure that falls into layer 226, TaN layer 224b, workfunction layers 228 and top barrier layer 230 and is had U type shape as shown in Figure 5.
In addition, see also Fig. 6, Fig. 6 is the sketch map of another change type of second preferred embodiment.Metal gates 220b that this change type provided and back gate dielectric process integration, and nitrogen is caught and is fallen into layer 226 and still be arranged between the double-decker of nitrogenous layer 224.That is to say; After forming gate trench; Substrate 200 or dielectric layer are exposed to gate trench bottom, just in gate trench, form in regular turn subsequently high-k (high-K) gate dielectric 222, the TiN layer 224a of nitrogenous layer 224, nitrogen catch the TaN layer 224b that fall into layer 226, nitrogenous layer 224, workfunction layers 228, top barrier layer 230, with Low ESR metal level 232.Therefore, high-k (high-K) gate dielectric 222 among the metal gates 220b that this change type provided, nitrogenous layer 224 (comprising TiN layer 224a and TaN layer 224b), nitrogen are caught the cross-section structure that falls into layer 226, workfunction layers 228, top barrier layer 230 and are all had U type shape.
According to second preferred embodiment provided by the present invention; Double-decker in nitrogenous layer 224; Be that the nitrogen that complete nonnitrogenous ion is set in the middle of TiN layer 224a and the TaN layer 224b is caught sunken layer 226; And the nitrogen that utilizes nonnitrogenous ion catches and falls into layer 226 and catch in the nitrogenous layer of its upper and lowers 224 nitrogen ion, oxonium ion or carbon ion, with the metal ion diffusion rate that increases workfunction layers 228 and improve its diffusion result.Therefore accomplish after the adjustment of metal gates 220a/220b; Nitrogen is caught sunken layer 226 and can be captured the nitrogen ion in the nitrogenous layer 224 and comprise the NITROGEN IN LOW CONCENTRATION ion; And the diffusivity of metal is raised in the workfunction layers 228, and reaches the purpose of the work function of adjustment metal gates 220a/220b to 3.9～4.3eV of expection.
See also Fig. 7 to Fig. 8; Fig. 7 to Fig. 8 is respectively the 3rd preferred embodiment of metal gate structure provided by the present invention and the sketch map of change type thereof; And the 3rd preferred embodiment also adopts the back grid technology; In addition in the 3rd preferred embodiment with first its material of preferred embodiment components identical with the configuration can directly go the reference first preferred embodiment disclose, so repeat no more in this.As shown in Figure 7, this preferred embodiment at first provides substrate 300, and is formed with a plurality of shallow-channel insulations (STI) 302 in order to electrical isolation to be provided in the substrate 300.Form semiconductor element 310 at least in the substrate 300.Semiconductor element 310 comprises metal gates 320a, lightly doped drain (LDD) 312.Because the semiconductor element 310 that this preferred embodiment provided also is the n type semiconductor elements, so lightly doped drain (LDD) 312 is a n type lightly doped drain (LDD).And the sidewall around the metal gates 320a of semiconductor element 310 still comprises clearance wall 314; Clearance wall 314 is preferably the structure of composite film.Semiconductor element 310 also comprises n type source/drain 316, with the metal silicide 318 in order to the resistance that reduces contact interface.In this preferred embodiment, also can integrate the epitaxial loayer manufacturing n type source/drain 316 that the utilization of selective epitaxial growth (SEG) method includes SiC.Contact hole etching stopping layer (CESL) 340 and internal layer dielectric (ILD) layer 342 and in semiconductor element 310 and substrate 300, be formed with in regular turn.
Please continue to consult Fig. 7.This 3rd preferred embodiment can with first gate dielectric process integration; Comprise in regular turn in the metal gates 320a gate dielectric 322, nitrogen catch fall into layer 326, nitrogenous layer 324, workfunction layers 328, top barrier layer 330, with Low ESR metal level 332; These retes from bottom to top are stacked in the gate trench (figure does not show) of metal gates 320a in regular turn, and Low ESR metal level 332 fills up the gate trench of metal gates 320a.Nitrogenous layer 324 can comprise TiN, TaN or its combination, comprises the for example double-decker of TiN layer 324a and TaN layer 324b but be preferably, but is not limited thereto.TiN layer 324a in the nitrogenous layer 324 is as bottom barrier layer as previously mentioned, and TaN layer 324b is then as etching stopping layer.In addition, the bottom of metal gates 320a also can comprise dielectric layer (figure does not show), is formed at before the gate dielectric 322.
It should be noted that this preferred embodiment is provided with nitrogen and catches sunken layer 326 between high-k (high-K) gate dielectric 322 and nitrogenous layer 324, its thickness is between 10 dust to 70 dusts.Nitrogen is caught and is fallen into layer 326 and do not comprise any nitrogen ion, and nitrogen is caught and fallen into layer 326 and be selected from the group that Ti, Ta, La, Y, Hf, Nb, Zr and V form.Those of ordinary skill should be known in this field; When the work function of adjustment metal gates 320a, the aluminium ion in the workfunction layers 328 can be adjusted the work function of n type metal gates utmost point 320a via the interface that diffuses into high-k (high-K) gate dielectric 322 and nitrogenous layer 324.At this moment, the nitrogen that this preferred embodiment provided is caught and fallen into layer 326 is in order to the nitrogen ion in the nitrogenous layer 324 above catching, and reduces the resistance barrier effect of nitrogenous layer 324, to increase aluminum ions diffusion rate and to improve aluminum ions diffusion result.
Please continue to consult Fig. 7.Therefore, after the work function of adjusting metal gates 320a, the nitrogen of complete nonnitrogenous ion is caught sunken layer and is caught next NITROGEN IN LOW CONCENTRATION ion 326 interior can comprising by nitrogenous layer 324 originally.And remove unnecessary Low ESR metal level 332, top barrier layer 330, workfunction layers 328 and TaN layer 324b through flatening process such as chemico-mechanical polishing (CMP) technology after; Obtain metal gates 320a, and the cross-section structure of the TaN layer 324b among the metal gates 320a, workfunction layers 328 and top barrier layer 330 has U type shape as shown in Figure 6.
In addition, see also Fig. 8, Fig. 8 is the sketch map of the change type of first preferred embodiment.Metal gates 320b that this change type provided and back gate dielectric process integration, and nitrogen is caught and is fallen into layer 326 and still be arranged between high-k (high-K) gate dielectric 322 and the nitrogenous layer 324.That is to say; After forming gate trench; Substrate 300 or dielectric layer are exposed to gate trench bottom, just in gate trench, form in regular turn subsequently high-k (high-K) gate dielectric 322, nitrogen catch fall into layer 326, nitrogenous layer 324, workfunction layers 328, top barrier layer 330, with Low ESR metal level 332.Therefore high-k (high-K) gate dielectric 322, the nitrogen among the metal gates 320b that this change type provided is caught the cross-section structure that falls into layer 326, nitrogenous layer 324 (comprising TiN layer 324a and TaN layer 324b), workfunction layers 328, top barrier layer 330 and is all had U type shape.
According to the 3rd preferred embodiment provided by the present invention; The nitrogen that complete nonnitrogenous ion is set between nitrogenous layer 324 and high-k (high-K) gate dielectric 322 is caught sunken layer 326; And the nitrogen that utilizes nonnitrogenous ion catches and falls into layer 326 and catch in the nitrogenous layers of top 324 nitrogen ion, with the resistance barrier effect that reduces nitrogenous layer 324, increase the metal ion diffusion rate of workfunction layers 328 and improve its diffusion result.Therefore accomplish after the adjustment of metal gates 320a/320b; Nitrogen is caught sunken layer 326 and can be captured the nitrogen ion in the nitrogenous layer 324 and comprise the NITROGEN IN LOW CONCENTRATION ion; And the diffusivity of special metal is raised in the workfunction layers 328, and 3.9～4.3eV of work function to the expection of adjustment metal gates 320a/320b.
In sum; According to metal gate structure provided by the present invention; Be to utilize to be arranged between workfunction layers and the high dielectric constant gate dielectric layer; The nitrogen of complete nonnitrogenous ion is caught the nitrogen ion that falls in the layer seizure nitrogenous layer, hinders effect, increases the metal ion diffusion rate of workfunction layers and improves its diffusion result with the resistance that reduces nitrogenous layer.Therefore accomplish after the adjustment of workfunction metal; Nitrogen is caught and is fallen into layer and can capture the nitrogen ion in the nitrogenous layer and comprise the NITROGEN IN LOW CONCENTRATION ion, and the diffusivity of special metal is raised and reaches the purpose of the work function of adjustment metal gates to 3.9～4.3eV of expection in the workfunction layers.In view of the above, the present invention has the metal gate structure than high-reliability.
The above is merely the preferred embodiments of the present invention, and all equivalent variations and modifications of doing according to claim of the present invention all should belong to covering scope of the present invention.
Claims (24)
1. metal gate structure includes:
High dielectric constant gate dielectric layer;
Workfunction layers;
Nitrogenous layer is arranged between this workfunction layers and this high dielectric constant gate dielectric layer; And
Nitrogen is caught and is fallen into layer, be arranged between this workfunction layers and this high dielectric constant gate dielectric layer, and this nitrogen is caught to fall into and layer do not comprised any nitrogen ion.
2. metal gate structure as claimed in claim 1, wherein this nitrogen is caught sunken layer and is selected from the group that titanium, tantalum, lanthanum, yttrium, hafnium, niobium, zirconium and vanadium are formed.
3. metal gate structure as claimed in claim 1, wherein this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this nitrogenous layer, and this nitrogen is caught the cross-section structure that falls into layer with this workfunction layers and had U type shape.
4. metal gate structure as claimed in claim 1; Wherein this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this nitrogenous layer, and this high dielectric constant gate dielectric layer, this nitrogenous layer, this nitrogen catch fall into layer, the cross-section structure of this workfunction layers has U type shape.
5. metal gate structure as claimed in claim 1, wherein this nitrogenous layer also comprises titanium nitride, tantalum nitride or its combination.
6. metal gate structure as claimed in claim 5, wherein this nitrogenous layer is a double-decker.
7. metal gate structure as claimed in claim 6, wherein this nitrogen is caught and is fallen into layer and be located among this double-decker, and the cross-section structure of this workfunction layers has U type shape.
8. metal gate structure as claimed in claim 6, wherein this nitrogen is caught and is fallen into layer and be located among this double-decker, and this high dielectric constant gate dielectric layer, this nitrogenous layer, this nitrogen are caught the cross-section structure that falls into layer, this workfunction layers and had U type shape.
9. metal gate structure as claimed in claim 1, wherein this nitrogen is caught and is fallen into layer and be arranged between this nitrogenous layer and this high dielectric constant gate dielectric layer, and the cross-section structure of this workfunction layers has U type shape.
10. metal gate structure as claimed in claim 1; Wherein this nitrogen is caught and is fallen into layer and be arranged between this nitrogenous layer and this high dielectric constant gate dielectric layer, and the cross-section structure that this high dielectric constant gate dielectric layer, this nitrogen are caught sunken layer, this nitrogenous layer, this workfunction layers has U type shape.
11. metal gate structure as claimed in claim 1, wherein this workfunction layers comprises titanium aluminide single layer structure, Titanium Trialuminum single layer structure or aluminium/titanium double-decker.
12. metal gate structure as claimed in claim 1 also comprises top barrier layer and Low ESR metal level, this top barrier layer and Low ESR metal level are arranged on this workfunction layers in regular turn.
13. a metal gate structure includes:
High dielectric constant gate dielectric layer;
Workfunction layers
Nitrogenous layer is arranged between this workfunction layers and this high dielectric constant gate dielectric layer; And
Nitrogen is caught and is fallen into layer, be arranged between this workfunction layers and this high dielectric constant gate dielectric layer, and this nitrogen is caught to fall into and layer comprised the NITROGEN IN LOW CONCENTRATION ion.
14. metal gate structure as claimed in claim 13, wherein this nitrogen is caught sunken layer and is selected from the group that titanium, tantalum, lanthanum, yttrium, hafnium, niobium, zirconium and vanadium are formed.
15. metal gate structure as claimed in claim 13, wherein this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this nitrogenous layer, and this nitrogen is caught the cross-section structure that falls into layer with this workfunction layers and had U type shape.
16. metal gate structure as claimed in claim 13; Wherein this nitrogen is caught and is fallen into layer and be arranged between this workfunction layers and this nitrogenous layer, and this high dielectric constant gate dielectric layer, this nitrogenous layer, this nitrogen catch fall into layer, the cross-section structure of this workfunction layers has U type shape.
17. metal gate structure as claimed in claim 13, wherein this nitrogenous layer also comprises titanium nitride, tantalum nitride or its combination.
18. metal gate structure as claimed in claim 17, wherein this nitrogenous layer is a double-decker.
19. metal gate structure as claimed in claim 18, wherein this nitrogen is caught and is fallen into layer and be located among this double-decker, and the cross-section structure of this workfunction layers has U type shape.
20. metal gate structure as claimed in claim 18, wherein this nitrogen is caught and is fallen into layer and be located among this double-decker, and this high dielectric constant gate dielectric layer, this nitrogenous layer, this nitrogen are caught the cross-section structure that falls into layer, this workfunction layers and had U type shape.
21. metal gate structure as claimed in claim 13, wherein this nitrogen is caught and is fallen into layer and be arranged between this nitrogenous layer and this high dielectric constant gate dielectric layer, and the cross-section structure of this workfunction layers has U type shape.
22. metal gate structure as claimed in claim 13; Wherein this nitrogen is caught and is fallen into layer and be arranged between this nitrogenous layer and this high dielectric constant gate dielectric layer, and the cross-section structure that this high dielectric constant gate dielectric layer, this nitrogen are caught sunken layer, this nitrogenous layer, this workfunction layers has U type shape.
23. metal gate structure as claimed in claim 13, wherein this workfunction layers comprises titanium aluminide single layer structure, Titanium Trialuminum single layer structure or aluminium/titanium double-decker.
24. metal gate structure as claimed in claim 13 also comprises top barrier layer and Low ESR metal level, this top barrier layer and Low ESR metal level are arranged on this workfunction layers in regular turn.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110104782XA CN102760758A (en) | 2011-04-26 | 2011-04-26 | Metal gate structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110104782XA CN102760758A (en) | 2011-04-26 | 2011-04-26 | Metal gate structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102760758A true CN102760758A (en) | 2012-10-31 |
Family
ID=47055149
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110104782XA Pending CN102760758A (en) | 2011-04-26 | 2011-04-26 | Metal gate structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102760758A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104299897A (en) * | 2013-07-17 | 2015-01-21 | 格罗方德半导体公司 | Integrated circuits having replacement metal gates with improved threshold voltage performance and methods for fabricating the same |
| CN109904231A (en) * | 2017-12-11 | 2019-06-18 | 中芯国际集成电路制造(北京)有限公司 | Semiconductor devices and its manufacturing method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101027770A (en) * | 2004-09-27 | 2007-08-29 | 英特尔公司 | A metal gate electrode semiconductor device |
| US20100052070A1 (en) * | 2008-08-27 | 2010-03-04 | Taiwan Semiconductor Manufacturing Company, Ltd. | novel device scheme of hkmg gate-last process |
| US20100068877A1 (en) * | 2008-09-12 | 2010-03-18 | Taiwan Semiconductor Manufacturing Company, Ltd. | Method for tuning a work function of high-k metal gate devices |
| CN1947242B (en) * | 2004-04-20 | 2010-09-29 | 英特尔公司 | A method for making a semiconductor device having a high-K gate dielectric layer and a metal gate electrode |
| US20110006354A1 (en) * | 2009-07-08 | 2011-01-13 | Taiwan Semiconductor Manufacturing Company, Ltd. | Metal gate structure of a semiconductor device |
-
2011
- 2011-04-26 CN CN201110104782XA patent/CN102760758A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1947242B (en) * | 2004-04-20 | 2010-09-29 | 英特尔公司 | A method for making a semiconductor device having a high-K gate dielectric layer and a metal gate electrode |
| CN101027770A (en) * | 2004-09-27 | 2007-08-29 | 英特尔公司 | A metal gate electrode semiconductor device |
| US20100052070A1 (en) * | 2008-08-27 | 2010-03-04 | Taiwan Semiconductor Manufacturing Company, Ltd. | novel device scheme of hkmg gate-last process |
| US20100068877A1 (en) * | 2008-09-12 | 2010-03-18 | Taiwan Semiconductor Manufacturing Company, Ltd. | Method for tuning a work function of high-k metal gate devices |
| US20110006354A1 (en) * | 2009-07-08 | 2011-01-13 | Taiwan Semiconductor Manufacturing Company, Ltd. | Metal gate structure of a semiconductor device |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104299897A (en) * | 2013-07-17 | 2015-01-21 | 格罗方德半导体公司 | Integrated circuits having replacement metal gates with improved threshold voltage performance and methods for fabricating the same |
| CN109904231A (en) * | 2017-12-11 | 2019-06-18 | 中芯国际集成电路制造(北京)有限公司 | Semiconductor devices and its manufacturing method |
| CN109904231B (en) * | 2017-12-11 | 2022-03-29 | 中芯国际集成电路制造(北京)有限公司 | Semiconductor device and method for manufacturing the same |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3159929A2 (en) | Method and device for metal gate stacks | |
| US8673758B2 (en) | Structure of metal gate and fabrication method thereof | |
| CN102842491B (en) | The manufacture method of metal gates | |
| US8987096B2 (en) | Semiconductor process | |
| US9006092B2 (en) | Semiconductor structure having fluoride metal layer and process thereof | |
| US9029959B2 (en) | Composite high-k gate dielectric stack for reducing gate leakage | |
| JP5644625B2 (en) | Semiconductor device and manufacturing method thereof | |
| US9484427B2 (en) | Field effect transistors having multiple effective work functions | |
| TW201436285A (en) | Hybrid gate last integration scheme for multi-layer high-k gate stacks | |
| US9799770B2 (en) | FinFET structure device | |
| US10141193B2 (en) | Fabricating method of a semiconductor device with a high-K dielectric layer having a U-shape profile | |
| US20120261770A1 (en) | Metal gate structure | |
| US11177346B2 (en) | Semiconductor device | |
| US7662685B2 (en) | Semiconductor device and manufacturing method thereof | |
| US9034705B2 (en) | Method of forming semiconductor device | |
| KR20120095999A (en) | Interface layer reduction method, method for forming high dielectric constant gate insulating film, high dielectric constant gate insulating film, high dielectric constant gate oxide film, and transistor having high dielectric constant gate oxide film | |
| US10164052B2 (en) | Semiconductor device and method for fabricating the same | |
| CN103000582B (en) | Resistance and preparation method thereof | |
| CN102760758A (en) | Metal gate structure | |
| CN110246803A (en) | Semiconductor element and preparation method thereof | |
| US8329597B2 (en) | Semiconductor process having dielectric layer including metal oxide and MOS transistor process | |
| CN102683397B (en) | Metal gate structure and preparation method thereof | |
| US20170062615A1 (en) | Method of forming semiconductor device | |
| US20130146954A1 (en) | Method Of Memory Array And Structure Form | |
| CN102543744A (en) | Transistor and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20121031 |