JP3905977B2 - Manufacturing method of semiconductor device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention is used as a method of manufacturing a semiconductor device, particularly as an electrode of a capacitor.RutheniumConcerning formation.
[0002]
[Prior art]
In recent years, along with the high integration of semiconductor integrated circuits, the miniaturization of circuits has been progressing, and the cell area of capacitors has become very small. When the cell area is reduced, the capacitance of the capacitor is also reduced. However, there is a demand that the capacitance of the capacitor cannot be reduced so much in terms of sensitivity and soft error. As a method for solving this, in addition to a method of forming capacitors three-dimensionally to increase the cell area as much as possible to increase the capacitor capacity, a method of using an insulating film having a high dielectric constant as the capacitor insulating film has been studied.
[0003]
(Ba, Sr) TiO as a representative insulating film having a high dielectric constant_Three However, when using such an oxide dielectric, in order to prevent the formation of an insulating film having a low dielectric constant at the interface between the electrode and the dielectric film, the metal is not oxidized or is oxidized even if it is oxidized. It is necessary to use a material exhibiting conductivity as an electrode. In recent years, ruthenium (Ru), which exhibits metal conductivity even when oxidized, has been studied as an electrode material for capacitors having such properties.
[0004]
Ru as electrode, (Ba, Sr) TiO_Three An example of a method for forming a capacitor using an insulating film will be described below with reference to FIGS. 14 (a) to 15 (d).
First, after forming an element isolation region 2 by STI (Shallow Trench Isolation) on a p-type Si substrate 1, a gate insulating film 3a, a gate electrode (word line) 3b,⁺ The diffusion layer 4 is formed. Thereafter, an interlayer insulating film 5a is deposited and planarized, and then the bit line 6 is formed. Subsequently, after depositing and planarizing the interlayer insulating film 5b, a contact hole is opened and the W film 7 is embedded and processed (FIG. 14A).
[0005]
Next, after depositing and planarizing the interlayer insulating film 5c, a contact hole is opened (FIG. 14B).
Next, the Ru film 8 is made of Ru (C_Five H_Five )₂ (Cyclopentadienyl ruthenium (common name: ruthenocene), hereinafter (C_Five H_Five ) To Cp and (C_Five H_Five )₂ (Cp)₂ And O)₂ Then, the SOG film 9 is applied over the entire surface, and the SOG film 9 and the Ru film 8 on the interlayer insulating film 5c are removed by CMP (Chemical Mechanical Polishing) (FIG. 14C). ).
[0006]
Further, after all the SOG film 9 is removed with a sufficiently diluted HF aqueous solution or HF vapor, (Ba, Sr) TiO 2 is removed._Three The film 10 is deposited by the CVD method. Thereafter, the Ru film 11 is deposited by the CVD method and processed as an upper electrode (FIG. 15D).
[0007]
In order to increase the capacitor capacity, it is necessary to fabricate a three-dimensional capacitor, and (Ba, Sr) TiO with a high dielectric constant._Three However, it is necessary to form the electrode and the oxide dielectric by the CVD method as described above.
[0008]
However, in general, a metal film formed by a CVD method or a metal oxide film having metal conductivity has poor surface morphology, and when this is used as an electrode of a capacitor, leakage current increases due to electric field concentration. Also, if an ultra-thin electrode is formed in order to realize miniaturization, the film becomes an island shape and the film is not connected. If this is used as a capacitor electrode, the capacitor area cannot be obtained, and the capacitor There also arises a problem that a capacity required for operation cannot be secured.
[0009]
Further, when forming a columnar capacitor, if the surface morphology of the Ru film is poor, a seam as shown in FIG. 16 is formed in the central portion of the Ru electrode 8 when the Ru film on the interlayer insulating film 5c is removed by the CMP method. It will occur. Therefore, (Ba, Sr) TiO as a capacitor insulating film_Three When the film is deposited, a recess is formed in the capacitor insulating film in the seam portion, and there is a problem that leakage current increases due to electric field concentration.
[0010]
[Problems to be solved by the invention]
Thus, Ru is an oxide (ruthenium oxide: RuO₂ ) Also exhibits metal conductivity, so (Ba, Sr) TiO_Three Although it is promising as an electrode material for capacitors having a dielectric as a dielectric material, it is difficult to obtain a good surface morphology when formed by CVD, and Ru and RuO₂ There is a problem that is formed in an island shape.
[0011]
  The present invention has been made with respect to the above conventional problems, and becomes a capacitor electrode.RutheniumAn object of the present invention is to provide a production method that is excellent in surface morphology and capable of suppressing island growth during formation.
[0012]
[Means for Solving the Problems]
  In the present invention, a metal oxide is used as a dielectric film, and the electrodes sandwiching the dielectric film are used asRuthenium filmIn a method of manufacturing a semiconductor device having a capacitor usingIn the formation process of each of the electrodes, a catalyst is formed on the base surface on which the electrodes are formed.Organic group ruthenocene in which one or more hydrogens of the ruthenocene or cyclopentadienyl ring are replaced by organic functional groupsSource gas ligand comprisingA cyclopentadienyl ring which forms a skeleton of a cyclopentadienyl group or a cyclopentadienyl group having an organic functional group is a reaction to decompose a 1-carbon group or a 4-carbon group or a 1-carbon group Under conditions that promote the decomposition of the group into two groups of two carbonsThe ruthenium film is formed by a CVD method using the source gas and oxygen.It is characterized by that.
[0014]
  In the catalyst formed on the base surface, a substance containing at least a group 8 or group 1B element (a simple substance or a compound of the element) is included.can give.
  The catalyst preferably has a film thickness or particle size of 0.5 nm or more. For example, a material containing a group 8 or 1B element is formed by sputtering, or a group 8 or 1B element is formed. It can be formed by a method such as dipping in a solution.
[0018]
The Ru film growth mechanism and the like for showing the effectiveness of the present invention will be described below.
When the growth of the Ru film was examined in detail, it was found that the Ru growth occurred after a certain time (introduction time) had elapsed. When the film was formed at 230 ° C., it was found that there was an introduction time of 20 minutes or more. When a metal film used for an LSI such as W or TiN is formed by the CVD method, such an introduction time of the order of several tens of minutes is not seen, and it can be seen that Ru CVD is very specific. Further, as a result of examining the Ru film thickness with respect to the introduction time and the growth time in more detail, as shown in FIG. 13, Ru grows at a very slow growth rate during the introduction time, and a certain film thickness or grain size (0 It was found that the growth rate rapidly increased at about .5-1.5 nm).
[0019]
As a result of investigating the reaction process during the introduction time using a quadrupole mass spectrometer (Q-Mass), Ru (Cp)₂ Is a reaction in which RuCp is decomposed into RuCp and Cp, RuCp is decomposed into Ru and Cp, and when RuCp is decomposed, Cp is decomposed into two carbon groups and three carbon groups. The group is bonded to Ru to form ruthenium methyl acetylide (RuC≡CCH_Three ) (See FIG. 11).
[0020]
Further, when the reaction was examined in more detail, during the introduction time, the raw material Ru was consumed in the reaction for producing ruthenium methyl acetylide, and the amount of Ru used for the reaction in which RuCp was decomposed into Ru and Cp was small. Since acetylide volatilizes and Ru is not formed on the wafer, it has been found that the deposition rate of Ru is extremely slow and its density is low. A cross-sectional SEM image of the Ru film formed by such a reaction is shown in FIG. It can be seen that the surface morphology is very poor due to the low initial nuclear density.
[0021]
Therefore, several layers of Ru were densely formed to serve as a catalyst before the CVD of Ru, and then it was found that a Ru film having a very smooth surface can be obtained by depositing Ru by CVD. . In this case, no introduction time was observed, and it was found that Ru film growth occurred immediately. This is because Ru functions as a catalyst and the Cp ring decomposes into a group of one carbon and four carbons (or a group of one carbon and two groups of two carbons) when a raw material gas is supplied. This is to promote the reaction. In addition, it has been found that a catalyst or a simple substance containing at least one group 8 or group 1B element in addition to Ru is also effective.
[0022]
  Also,As a reference example,When the substrate was processed so that the initial nuclei were formed as densely as possible during the introduction time, the introduction time and the growth time were seen as in the case where the substrate was not treated, but the introduction time was not treating the substrate. It was found that the Ru film formed was shorter than the case without it and had a very good surface morphology. This is because by performing the base treatment, a negative charge is provided to the Ru (Cp) group or the like, and the reaction in which the ruthenium acetylide derivative is generated is suppressed.
[0023]
  From the above, as a capacitor electrodeRuWhen forming a film by the CVD method, a catalyst that promotes the reaction of CVD is formed densely on the base surface,Ru'sGrowth reaction takes place quickly and smoothes the surface morphology of the deposited filmbe able to.
[0024]
  In addition, by applying a ground treatment that suppresses the formation of ruthenium methyl acetylide derivatives that occur during the introduction time.(Reference example)The initial nucleation rate can be increased and the initial nuclei density can be increased, and the surface morphology of the formed film can be smoothed.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(1) Embodiment 1
First, the manufacturing process of the capacitor according to the first embodiment of the present invention will be described with reference to FIGS. 1 (a) to 3 (g).
[0026]
First, an element isolation region 2 having an STI structure is formed on a p-type Si substrate 1, and then a gate insulating film 3a, a gate electrode 3b (to be a word line), and a source / drain diffusion layer (n⁺ A MOS transistor composed of (diffusion layer) 4 is formed. Thereafter, an interlayer insulating film 5a is deposited and planarized, and then the bit line 6 is formed. Thereafter, an interlayer insulating film 5b is further deposited and planarized, and then a contact hole is opened (FIG. 1A).
[0027]
Next, after the W film 7 is deposited on the entire surface, the W film 7 on the interlayer insulating film 5b is removed by an etch back method or a CMP method, and is buried only in the contact hole (FIG. 1B). Subsequently, an interlayer insulating film 5c is deposited and planarized, and then a contact hole is opened (FIG. 1C).
[0028]
Next, the substrate is RuCl_Three A process of immersing in an ethylene glycol solution of Ru or a plating solution of Ru is performed to form Ru8 of 0.5 nm or more on the entire surface (FIG. 2D). Thereafter, Ru (Cp) using Ar gas as a carrier at a substrate temperature of 180 to 400 ° C. and a pressure of 0.01 to 10 Torr.₂ And O₂ (Atmosphere O₂ The Ru film 8 is deposited on the entire surface by introducing a concentration of 40% or less into the chamber (FIG. 2E). Next, after applying an SOG film (not shown) over the entire surface, the SOG film and the Ru film on the interlayer insulating film 5c are removed by CMP, and the SOG film remaining in the contact hole is removed with HF vapor. A lower electrode made of the Ru film 8 is formed (FIG. 2F).
[0029]
Next, (Ba, Sr) TiO_Three A film 10 is deposited on the entire surface by a CVD method. Thereafter, Ru (Cp) using Ar gas as a carrier at a substrate temperature of 100 to 200 ° C. and a pressure of 1 to 100 Torr.₂ And O₂ After forming the initial nucleus by exposing the substrate to a mixed gas of Ru (Cp) using Ar gas as a carrier at a substrate temperature of 200-450 ° C. and a pressure of 0.01-10 Torr.₂ And O₂ (Atmosphere O₂ A concentration of 40% or less) is introduced into the chamber, and the Ru film 11 is deposited on the entire surface and processed as an upper electrode (FIG. 3G).
[0030]
Thus, by immersing in a Ru-containing solution immediately before Ru CVD, Ru nuclei of 0.5 nm or more can be densely attached to the underlying surface. The reaction process of the Ru film in this case was examined in detail using a quadrupole mass spectrometer, and as a result, RuCp was composed of one carbon group and four carbon groups (or one carbon group and two carbon atoms). It was found that Ru was growing in a reaction in which Ru was generated by decomposition into a group (see FIG. 12). In addition, the Ru nucleus of 0.5 nm or more functions as a catalyst, and as soon as the raw material gas is supplied, the Cp ring is composed of a group of one carbon and a group of four carbons (or a group of one carbon and two carbons of two. Group) can be promoted, and a smooth surface Ru film can be obtained.
[0031]
In the above example, the treatment of immersing in a solution containing Ru was performed. However, instead of Ru, the substrate was immersed in a solution containing a group 8 or 1B element such as Pt, Au, Ir, Rh, etc. Alternatively, when the compound is used as a nucleus, the same effect can be obtained by the same catalytic action.
[0032]
(2) Embodiment 2
Next, a manufacturing process of a capacitor according to the second embodiment of the present invention will be described with reference to FIGS. 4 (a) to 6 (h).
[0033]
First, an element isolation region 2 having an STI structure is formed on a p-type Si substrate 1, and then a gate insulating film 3a, a gate electrode 3b, and source / drain diffusion layers (n⁺ A MOS transistor composed of (diffusion layer) 4 is formed. Thereafter, an interlayer insulating film 5a is deposited and planarized, and then the bit line 6 is formed. Thereafter, an interlayer insulating film 5b is further deposited and planarized, and then a silicon nitride film 5d is deposited and a contact hole is formed (FIG. 4A).
[0034]
Next, after the W film 7 is deposited on the entire surface, the W film 7 on the silicon nitride film 5d is removed by an etch back method or a CMP method, and is buried only in the contact hole (FIG. 4B). Subsequently, an interlayer insulating film 5c is deposited and planarized, and then a contact hole is opened (FIG. 4C).
[0035]
Next, a thin Ru film 8 is formed so as to have a film thickness of 0.5 nm or more by sputtering (FIG. 5D). Thereafter, Ru (EtCp) using Ar gas as a carrier at a substrate temperature of 180 to 400 ° C. and a pressure of 0.01 to 10 Torr.₂ (Et represents an ethyl group) and O₂ (Atmosphere O₂ A Ru film 8 is deposited on the entire surface by introducing a concentration of 40% or less into the chamber (FIG. 5E). Thereafter, the Ru film 8 on the interlayer insulating film 5c is removed by CMP, and the Ru film 8 is embedded in the contact hole (FIG. 5F). Further, the interlayer insulating film 5c is removed by wet etching or reactive ion etching with a dilute HF aqueous solution, and a lower electrode made of the Ru film 8 is formed (FIG. 6G).
[0036]
Next, (Ba, Sr) TiO_Three A film 10 is deposited on the entire surface by a CVD method. Thereafter, the Ru film 11 is deposited on the entire surface in the same manner as in the case of the lower Ru electrode and processed as the upper electrode (FIG. 6H).
[0037]
In this way, by forming an ultra-thin Ru film of 0.5 nm or more immediately before performing Ru CVD, Ru nuclei can be densely attached to the underlying surface, and the EtCp skeleton is immediately formed during Ru-CVD. As shown in the SEM image of FIG. 17, a Cp ring promotes a reaction that decomposes into a group of 1 carbon and 4 groups of carbon (or a group of 1 carbon and 2 groups of 2 carbon). As shown, a smooth surface Ru film can be obtained.
[0038]
In the above example, Ru nuclei were formed by sputtering. However, the catalyst is similarly used when a simple substance or compound containing a group 8 or 1B element such as Pt, Au, Ir, Rh or the like instead of Ru is used as a nucleus. An effect | action arises and the same effect can be acquired.
[0039]
  (3)Reference example 1
  Next, the present inventionFirst reference exampleThe manufacturing process of the capacitor according to the above will be described with reference to FIGS. 7 (d) to 7 (f). In addition, since it is the same as the process (process of FIG. 1 (a)-FIG.1 (c)) shown to 1st Embodiment until the middle process, about 1st Embodiment, please refer to 1st Embodiment about these processes. The subsequent steps will be described.
[0040]
After the step of FIG.₂ Ru (EtCp) using Ar gas as a carrier at a substrate temperature of 200 to 450 ° C. and a pressure of 0.01 to 10 Torr after exposing the substrate to plasma or Ar plasma₂ And O₂ (Atmosphere O₂ A concentration of 40% or less) is introduced into the chamber, and the Ru film 8 is deposited on the entire surface (FIG. 7D). Thereafter, an SOG film (not shown) is applied to the entire surface, and then the SOG film and the Ru film 8 on the interlayer insulating film 5c are removed by CMP, and the SOG film remaining in the contact hole is removed with HF vapor. A lower electrode made of the Ru film 8 is formed (FIG. 7E).
[0041]
Next, (Ba, Sr) TiO_Three A film 10 is deposited on the entire surface by a CVD method. Thereafter, as in the case of the lower Ru electrode 8, O₂ After the substrate is exposed to plasma or Ar plasma, a Ru film 11 is deposited by a CVD method and processed as an upper electrode (FIG. 7 (f)).
[0042]
As described above, by performing plasma treatment on the substrate before forming the lower and upper Ru electrodes, the source gas is easily adsorbed due to micro damage, and the nuclear density is increased. Further, due to the occurrence of dangling bonds, electrons are donated to the Ru (EtCp) group, the acetylation reaction of Ru is suppressed, and the reaction for generating metal Ru is promoted. For this reason, initial nuclei are easily formed, island-like growth and surface morphology deterioration can be prevented, and a capacitor with good characteristics can be realized.
[0043]
In the above example, O before the Ru film formation.₂ Processing was performed in plasma or Ar plasma, but N₂ In plasma, Ne plasma or HCl, BCl_Three , Cl₂ , F₂ Even if the treatment is performed in a plasma containing halogen, the initial nucleus density can be increased, and a good capacitor can be formed.
[0044]
Moreover, as a plasma generation method, a parallel plate type, a helicon type, an ECR type, an inductive coupling type, or the like can be used. Further, when plasma treatment and Ru film formation are continuously performed without breaking the vacuum using, for example, a cluster type CVD apparatus, a smoother Ru film can be obtained.
[0045]
  (4)Reference example 2
  Next, the present inventionSecond reference exampleThe manufacturing process of the capacitor according to FIG. 8 will be described with reference to FIGS. 8D to 9G. In addition, since it is the same as the process (process of FIG. 4 (a)-FIG.4 (c)) shown to 2nd Embodiment until the process on the way, 2nd Embodiment is referred about these processes. The subsequent steps will be described.
[0046]
After the step of FIG. 4C, NH_Four F aqueous solution, HCl aqueous solution or tetramethylammonium hydroxide ((CH_Three )_Four NOH) is immersed in an aqueous solution, and then Ru (Cp) using Ar gas as a carrier at a substrate temperature of 180-400 ° C. and a pressure of 0.01-10 Torr.₂ And O₂ (Atmosphere O₂ A concentration of 40% or less) is introduced into the chamber, and the Ru film 8 is deposited on the entire surface (FIG. 8D). Thereafter, the Ru film 8 on the interlayer insulating film 5c is removed by CMP, and the Ru film 8 is embedded in the contact hole (FIG. 8E). Further, the interlayer insulating film 5c is removed by wet etching or reactive ion etching with a dilute HF aqueous solution, and a lower electrode made of the Ru film 8 is formed (FIG. 9F).
[0047]
Furthermore, (Ba, Sr) TiO_Three A film 10 is deposited on the entire surface by a CVD method. Thereafter, as in the case of the lower Ru electrode, the Ru film 11 is deposited on the entire surface and processed as the upper electrode (FIG. 9G).
[0048]
In this way, by processing in a solution containing halogen ions or in an alkaline solution before forming the Ru electrode, electrons are donated to the Ru (Cp) group from the anion adsorbed on the base surface, and Ru acetylide Reaction is suppressed, and the reaction to produce metal Ru is promoted. For this reason, initial nuclei are easily formed, island-like growth and surface morphology deterioration can be prevented, and a capacitor with good characteristics can be realized.
[0049]
In this way, when the substrate was processed so that the initial nuclei were formed as densely as possible during the introduction time, the introduction time and the growth time were seen in the same manner as when the substrate was not treated. 18 is shorter than when the substrate is not processed (when the substrate temperature is 230 ° C., 23 minutes without processing is now 14 minutes by performing this processing), and is shown in the SEM image of FIG. As shown, the formed Ru film was found to have a very good surface morphology. In this way, if the acetylation reaction of Ru is suppressed so that the introduction time until the initial nucleus reaches a size causing a catalytic action is shortened, the amount of Ru formed on the underlying surface increases, and the catalyst The initial nuclear density acting as can also be improved. As a result of detailed examination, it was found that a smooth Ru film can be obtained by treating the base so that the introduction time is 15 minutes or less.
[0050]
  (5)Reference example 3
  Next, the present inventionThird reference exampleThe manufacturing process of the capacitor according to FIG. 10 will be described with reference to FIGS. 10 (d) to 10 (f). In addition, since it is the same as the process (process of FIG. 1 (a)-FIG.1 (c)) shown to 1st Embodiment until the middle process, about 1st Embodiment, please refer to 1st Embodiment about these processes. The subsequent steps will be described.
[0051]
After the step of FIG. 1C, the substrate temperature is 200 ° C.₂ Gas or F diluted to 5%₂ The substrate is exposed to gas, and then Ru (MeCp) using Ar gas as a carrier at a substrate temperature of 200 to 450 ° C. and a pressure of 0.01 to 10 Torr.₂ (Me represents a methyl group) and O₂ (Atmosphere O₂ A concentration of 40% or more) into the chamber and RuO₂ A film 12 is deposited on the entire surface (FIG. 10D). Thereafter, an SOG film (not shown) is applied to the entire surface, and then the SOG film and RuO on the interlayer insulating film 5c are formed by CMP.₂ The film 12 is removed, the SOG film remaining in the contact hole is removed with HF vapor, and RuOO is removed.₂ A lower electrode made of the film 12 is formed (FIG. 10E).
[0052]
Next, (Ba, Sr) TiO_Three A film 10 is deposited on the entire surface by a CVD method. Then lower RuO₂ After treatment with halogen gas as in the case of electrode formation, RuO₂ A film 13 is deposited on the entire surface and processed as an upper electrode (FIG. 10F).
[0053]
In this way, RuO₂ By processing in an atmosphere containing halogen before forming the electrode, electrons are donated to the Ru (MeCp) group from the halogen adsorbed on the base surface, suppressing the acetylation reaction of Ru, and the formation reaction of metal Ru. The metal Ru and oxygen combine to form RuO₂ The reaction in which is formed is also promoted. For this reason, initial nuclei are easily formed, island-like growth and surface morphology deterioration can be prevented, and a capacitor with good characteristics can be realized.
[0054]
As mentioned above, although embodiment of this invention was described, Ru film | membrane with favorable surface morphology can be obtained by using this invention. FIG. 19 shows an SEM image when Ru is thinned to 20 nm. Despite the thin film of 20 nm, no island-like growth was observed, and it was found that Ru with a very smooth surface was formed conformally.
[0055]
The present invention is not limited to the above embodiments, and can be implemented with various modifications.
In the above embodiment, Ru or RuO₂ O when forming₂ Gas is introduced into the chamber, but O₂ O instead of_Three Or O radicals may be used. For example, when using O radicals, O radicals generated by microwave discharge may be introduced into the chamber.
[0056]
In the above embodiment, the capacitor insulating film has (Ba, Sr) TiO._Three Although explained using PZT, STO, Ta₂ O_Five , BTO, SBT, etc. may be used. Furthermore, a Ti film, a TiN film, or a laminated film thereof may be deposited as an adhesion layer on the base of the W film.
[0057]
Also, Ru (Cp)₂ , Ru (MeCp)₂ , Ru (EtCp)₂ In addition, if the skeleton is a ligand of Cp ring, the present invention can be applied. The same effect can be obtained with metallocene derivatives of metals other than Ru.
[0058]
In the explanation of the reaction mechanism, Ru (Cp) is used for easy understanding of the reaction.₂ However, even if a raw material in which one or more hydrogen atoms of the Cp group are substituted with an organic functional group such as a methyl group, an ethyl group, or a propyl group is used, It is the same that it is decomposed. In this case, for example, a methylcyclopentadienyl group (CH_Three When the Cp ring of the Cp group) is decomposed into a group of 1 carbon and 4 carbons, and the group of 1 carbon has a methyl group and reacts with oxygen, acetaldehyde (CH_Three CHO) or acetic acid (CH_Three COOH) (formaldehyde (HCHO) and formic acid (HCOOH) are produced when the same reaction is Cp group only).
In addition, the present invention can be implemented with various modifications without departing from the spirit of the present invention.
[0059]
【The invention's effect】
  According to the present invention, under predetermined conditionsRutheniumBy formingRutheniumIsland-like growth is suppressed, and a smooth surface morphology is obtained. Therefore, a highly reliable capacitor having excellent characteristics can be realized.
[Brief description of the drawings]
FIG. 1 is a process cross-sectional view showing a part of a manufacturing process according to a first embodiment of the present invention.
FIG. 2 is a process cross-sectional view showing a part of the manufacturing process according to the first embodiment of the present invention.
FIG. 3 is a process cross-sectional view showing a part of the manufacturing process according to the first embodiment of the present invention.
FIG. 4 is a process cross-sectional view showing a part of a manufacturing process according to a second embodiment of the present invention.
FIG. 5 is a process cross-sectional view showing a part of a manufacturing process according to a second embodiment of the present invention.
FIG. 6 is a process cross-sectional view showing a part of a manufacturing process according to a second embodiment of the present invention.
[Fig. 7] of the present invention.First reference exampleProcess sectional drawing which showed a part of manufacturing process which concerns on.
[Fig. 8] of the present inventionSecond reference exampleProcess sectional drawing which showed a part of manufacturing process which concerns on.
FIG. 9 shows the present invention.Second reference exampleProcess sectional drawing which showed a part of manufacturing process which concerns on.
FIG. 10 shows the present invention.Third reference exampleProcess sectional drawing which showed a part of manufacturing process which concerns on.
FIG. 11 is a diagram showing a difference spectrum between a mass spectrum during an introduction time at a substrate temperature of 230 ° C. and a mass spectrum at room temperature.
FIG. 12 shows a difference spectrum between a mass spectrum during Ru growth at a substrate temperature of 230 ° C. and a mass spectrum at room temperature.
FIG. 13 is a diagram schematically showing the relationship between Ru film thickness and gas supply time.
FIG. 14 is a process cross-sectional view showing a part of a manufacturing process according to the prior art.
FIG. 15 is a process cross-sectional view showing a part of a manufacturing process according to the prior art.
FIG. 16 is a diagram showing an example of a problem of the prior art.
FIG. 17 is a photomicrograph showing an SEM image when a Ru film is formed after catalyst formation.
FIG. 18 is a micrograph showing an SEM image when a Ru film is formed after the base treatment.
FIG. 19 is a photomicrograph showing an SEM image when Ru is thinned by the method of the present invention.
FIG. 20 is a photomicrograph showing an SEM image of a Ru film when the initial nuclear density is low.
[Explanation of symbols]
1 ... Si substrate
2. Element isolation region
3a ... Gate insulating film
3b ... Gate electrode
4 ... S / D diffusion layer
5a, 5b, 5c ... interlayer insulating film
5d ... silicon nitride film
6 ... Bit line
7 ... W film
8, 11 ... Ru film
9 ... SOG film
10 ... (Ba, Sr) TiO_Three film
12, 13 ... RuO₂ film

Claims (2)

In a method of manufacturing a semiconductor device having a capacitor using a metal oxide as a dielectric film and using a ruthenium film as an electrode sandwiching the dielectric film,
In each electrode forming step,
Forming a catalyst on the underlying surface on which each electrode is formed;
By the catalyst, a cyclopentadienyl group or a cyclohexane having an organic functional group, which is a ligand of a raw material gas composed of an organic group ruthenocene in which one or more hydrogens of a ruthenocene or cyclopentadienyl ring are substituted with an organic functional group. A reaction of decomposing a cyclopentadienyl ring forming a skeleton of a pentadienyl group into a group of one carbon and a group of four carbons or a reaction of decomposing into a group of one carbon and two carbons. A method for manufacturing a semiconductor device, comprising forming the ruthenium film by a CVD method using the source gas and oxygen under conditions to promote.   2. The method of manufacturing a semiconductor device according to claim 1, wherein the catalyst formed on the base surface is a substance containing at least an element of group 8 or group 1B.

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