JP2002252336A - Semiconductor device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce damages to a ferroelectric film by diffusing hydrogen or moisture through a contact to an upper electrode of an electronic device including the ferroelectric film. SOLUTION: A method for manufacturing a semiconductor device comprises a step of forming the electronic device having a lower electrode 102, and forming a capacity insulating film 103 using a ferroelectric element and an upper electrode 104 on a semiconductor substrate 100. The method further comprises steps of depositing an interlayer insulating film 105 on the substrate 100 including the electronic device, and forming the contact 106 arriving at the electrode 104 on the film 105. The method also comprises a step of depositing a conductive barrier film 107 and a conductive hydrogen barrier film 108 on the film 105 and the contact 106. The method also comprises steps of subjecting the film 107 and the film 108 in a region including the contact 106 to patterning, depositing a conductive film on the film 105 including upper parts thereof, patterning the conductive film, and forming wiring 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a semiconductor device including an electronic device using a ferroelectric film as a capacitor insulating film, and a method of manufacturing the same.

[0002]

2. Description of the Related Art An electronic device formed of a laminated film including a ferroelectric film, for example, a ferroelectric capacitor having a capacitor insulating film formed of a ferroelectric film has a high relative dielectric constant and exhibits a hysteresis characteristic. Because of the use of remanent polarization, in the field of large capacity capacitors or non-volatile memory,
It is being used instead of a conventional capacitor having a capacitor insulating film made of a silicon oxide film or a silicon nitride film.

A conventional semiconductor device and a method of manufacturing the same will be described below with reference to FIGS. 9 (a) to 9 (d) and FIGS.
This will be described with reference to FIG.

First, as shown in FIG. 9A, a silicon oxide film 101 is deposited to a thickness of 1500 nm on a semiconductor substrate 100 on which elements such as MOS transistors are formed, and then flattened by resist etch back. Next, as shown in FIG. 9B, a platinum film is deposited in order of 200 nm, a ferroelectric film made of strontium, bismuth, tantalum or the like is deposited in order of 200 nm, and a platinum film is deposited in order of 200 nm. A capacitance element including the electrode 102, the capacitance insulating film 103, and the upper electrode 104 is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere,
Damage to the ferroelectric film due to dry etching at the time of forming the capacitor is recovered.

Next, as shown in FIG. 9C, after a silicon oxide film 105 is deposited to a thickness of 500 nm, an upper electrode 104 is formed.
Is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to hydrogen or contact dry etching generated during deposition of the interlayer insulating film.

Next, as shown in FIG. 9D, for example, titanium nitride is deposited to a thickness of 50 nm, and is patterned to form a conductive barrier film 107 on a predetermined region including the contact 106.

Next, as shown in FIG. 10A, a contact 109 to a MOS transistor or the like other than the capacitive element is formed. Next, as shown in FIG. 10B, titanium 20 nm, titanium nitride 100 nm, aluminum 7
After depositing a metal film composed of four layers of 00 nm and 50 nm of titanium nitride, the wiring 110 is formed by patterning. Thereafter, annealing is performed at 450 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to metal film deposition and wiring dry etching.

Thereafter, an interlayer film is deposited for a multilayer wiring,
Contact formation, metal film deposition, and wiring formation are repeated, and finally a protective film is deposited and a pad opening is performed.

Here, damage (destruction of crystallinity) to the ferroelectric film occurs in various processes such as interlayer film deposition, conductive film deposition, or dry etching, and is recovered by annealing in an oxygen atmosphere. .

[0010]

When the crystallinity of a ferroelectric substance is destroyed, it is necessary to supply oxygen at a temperature as high as possible and sufficient oxygen in order to recover the crystallinity. Annealing performed after the formation of a wiring having a maximum thickness is about 400 ° C. to 450 ° C. On the other hand, damage in various steps including dry etching after wiring formation is applied to the ferroelectric film through the contact provided on the upper electrode. There is a problem that the recovery of the sex cannot be performed sufficiently.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an object of the present invention is to reduce damage to a ferroelectric film which penetrates a contact after a wiring forming step.

[0012]

In order to achieve the above object, a first semiconductor device according to the present invention comprises a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode. An electronic device including electrodes, an interlayer insulating film formed on a semiconductor substrate including the electronic device, a contact formed on the interlayer insulating film and reaching the upper electrode, and a conductive film formed on the interlayer insulating film and the contact A conductive hydrogen barrier film formed on the conductive barrier film, including the conductive barrier film and the contact, and a wiring formed on the interlayer insulating film, the conductive barrier film and the conductive hydrogen barrier film. Have.

In a first semiconductor device according to the present invention,
Preferably, the conductive barrier film is made of titanium nitride, and the conductive hydrogen barrier film is made of at least one of titanium, a titanium aluminum alloy, titanium aluminum nitride, aluminum nitride, and iridium oxide.

According to the first semiconductor device of the present invention,
Since the conductive hydrogen barrier film is formed after the contact is formed, it is possible to reduce the possibility that the ferroelectric film is damaged by a later process through the contact.
Further, it is not necessary to consider the diffusion of the elements in the conductive hydrogen barrier film into the upper electrode and the compatibility between the hydrogen barrier film and the upper electrode such as reactivity and adhesion.

A second semiconductor device according to the present invention is an electronic device including a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode, and a semiconductor substrate including the electronic device. A first insulating barrier film formed on the interlayer insulating film, a contact reaching the upper electrode formed on the interlayer insulating film, a first conductive barrier film formed on the interlayer insulating film and on the contact; A hydrogen barrier film formed on a first predetermined region of the conductive barrier film,
A second conductive barrier film formed on a second predetermined region wider than the first predetermined region of the first conductive barrier film so as to cover the hydrogen barrier film; and on the interlayer insulating film and the first and second conductive barrier films. And a wiring formed on the conductive barrier film.

In a second semiconductor device according to the present invention,
Preferably, the first and second conductive barrier films are made of titanium nitride, and the hydrogen barrier film is made of at least one of aluminum oxide, tantalum oxide, and titanium oxide.

According to the second semiconductor device of the present invention,
Since the hydrogen barrier film is formed after the contact is formed, it is possible to reduce damage caused in a later step through the contact. Further, it is not necessary to consider the diffusion of the elements in the hydrogen barrier film into the upper electrode and the compatibility of the hydrogen barrier film with the upper electrode, such as reactivity and adhesion.

Further, as compared with the first semiconductor device,
Since the electrical connection between the upper electrode and the wiring can be made through a conductive barrier film surrounding the hydrogen barrier film, an insulating film can be used as the hydrogen barrier film. Therefore,
It is possible to widen the selection range of the hydrogen barrier film.

A third semiconductor device according to the present invention is an electronic device including a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode, and a semiconductor substrate including the electronic device. An interlayer insulating film formed thereon, a contact formed in the interlayer insulating film to reach the upper electrode, a conductive barrier film formed on a first predetermined region of the interlayer insulating film including on the contact, and And a hydrogen barrier film formed on a second predetermined region narrower than the first predetermined region on the first predetermined region of the conductive barrier film, and on the interlayer insulating film, on the conductive barrier film, and And a wiring formed on the conductive hydrogen barrier film.

In a third semiconductor device according to the present invention,
Preferably, the conductive barrier film is made of titanium nitride, and the hydrogen barrier film is made of at least one of aluminum oxide, tantalum oxide, and titanium oxide.

According to the third semiconductor device of the present invention,
Since the hydrogen barrier film is formed after the contact is formed, it is possible to reduce damage caused in a later step through the contact. Further, it is not necessary to consider the diffusion of the elements in the hydrogen barrier film into the upper electrode and the compatibility of the hydrogen barrier film with the upper electrode, such as reactivity and adhesion.

Further, as compared with the above-mentioned second semiconductor device,
The electrical connection between the upper electrode and the wiring can be made through a conductive barrier film directly connected to the wiring because it has a larger area than the hydrogen barrier film formed immediately above. It can be used. Therefore, it is possible to widen the selection range of the hydrogen barrier film. Further, it is not necessary to form a conductive barrier film on the hydrogen barrier film.

In the first to third semiconductor devices according to the present invention, the capacitance insulating film using a ferroelectric is a layered perovskite-type composite oxide containing strontium, bismuth and tantalum, or lead, zirconium and It is preferable to be composed of any one of perovskite-type composite oxides containing titanium.

In the first to third semiconductor devices according to the present invention, it is preferable that the electrode is made of either platinum or a multilayer film containing platinum.

In the first to third semiconductor devices according to the present invention, it is preferable that the interlayer insulating film is made of one of a silicon oxide film and a silicon oxide film containing at least one of phosphorus and boron.

In the first to third semiconductor devices according to the present invention, it is preferable that the wiring is formed of a multilayer film including titanium as a lowermost layer and at least aluminum as an upper layer.

A first method of manufacturing a semiconductor device according to the present invention includes a step of forming an electronic device comprising a lower electrode, a capacitor insulating film using a ferroelectric, and an upper electrode on a semiconductor substrate; Depositing an interlayer insulating film on a semiconductor substrate including: a step of forming a contact reaching the upper electrode in the interlayer insulating film; a step of depositing a conductive barrier film on the interlayer insulating film and on the contact; A step of depositing a conductive hydrogen barrier film on the conductive barrier film, a step of patterning the conductive barrier film and the conductive hydrogen barrier film in a region including the contact, and a step of forming a conductive barrier film on the interlayer insulating film A step of depositing a conductive film on the conductive film and the conductive hydrogen barrier film; and a step of forming a wiring by patterning the conductive film.

According to the first method of manufacturing a semiconductor device according to the present invention, since the conductive hydrogen barrier film is formed after the contact is formed, the damage caused by the ferroelectric film in a later step is transmitted through the contact. Can be reduced. Further, it is not necessary to consider the diffusion of the elements in the conductive hydrogen barrier film into the upper electrode and the compatibility between the hydrogen barrier film and the upper electrode such as reactivity and adhesion.

A second method of manufacturing a semiconductor device according to the present invention comprises the steps of forming an electronic device comprising a lower electrode, a capacitor insulating film using a ferroelectric, and an upper electrode on a semiconductor substrate; Depositing an interlayer insulating film on a semiconductor substrate including: forming a contact reaching the upper electrode in the interlayer insulating film; depositing a first conductive barrier film on the interlayer insulating film and on the contact; Depositing a hydrogen barrier film on the first conductive barrier film, including on the contact;
Patterning in a predetermined region, depositing a second conductive barrier film on the first conductive barrier film and the hydrogen barrier film, covering the first predetermined region, and Patterning the first and second conductive barrier films in a wide second predetermined region, depositing a conductive film on the interlayer insulating film and on the first and second conductive barrier films, Forming a wiring by patterning the film.

According to the second method of manufacturing a semiconductor device according to the present invention, since the hydrogen barrier film is formed after the contact is formed, it is possible to reduce damage caused in a later step through the contact. be able to. further,
It is not necessary to consider the diffusion of elements in the hydrogen barrier film into the upper electrode and the compatibility between the hydrogen barrier film and the upper electrode such as reactivity and adhesion.

Further, as compared with the first method for manufacturing a semiconductor device, the electrical connection between the upper electrode and the wiring can be made through the conductive barrier film surrounding the hydrogen barrier film. It can be used. Therefore, it is possible to widen the selection range of the hydrogen barrier film.

A third method of manufacturing a semiconductor device according to the present invention comprises the steps of: forming an electronic device comprising a lower electrode, a capacitor insulating film using a ferroelectric, and an upper electrode on a semiconductor substrate; Depositing an interlayer insulating film on a semiconductor substrate including: a step of forming a contact reaching the upper electrode in the interlayer insulating film; a step of depositing a conductive barrier film on the interlayer insulating film and on the contact; Including, the step of depositing a hydrogen barrier film on the conductive barrier film, the taper etching using the same mask in the region including the contact the conductive barrier film and the hydrogen barrier film,
Patterning a conductive barrier film in a first predetermined region and a hydrogen barrier film in a second predetermined region smaller than the first predetermined region; and forming a pattern on the interlayer insulating film, the conductive barrier film and the hydrogen barrier film. And a step of forming a wiring by patterning the conductive film so as to cover at least the conductive barrier film.

According to the third method of manufacturing a semiconductor device according to the present invention, the hydrogen barrier film is formed after the contact is formed, so that damage caused in a later step is prevented from being transmitted through the contact. be able to. further,
It is not necessary to consider the diffusion of elements in the hydrogen barrier film into the upper electrode and the compatibility between the hydrogen barrier film and the upper electrode such as reactivity and adhesion.

Further, compared to the above-described second method for manufacturing a semiconductor device, the electrical connection between the upper electrode and the wiring has a larger area than the hydrogen barrier film formed immediately above, so that the wiring is directly connected to the wiring. Since this can be performed through the conductive barrier film to be connected, an insulating film can be used as the hydrogen barrier film. Therefore, it is possible to widen the selection range of the hydrogen barrier film. Further, since the conductive barrier film and the hydrogen barrier film can be patterned using the same mask, the number of mask steps can be reduced, and the formation of the conductive barrier film on the hydrogen barrier film becomes unnecessary.

A fourth method of manufacturing a semiconductor device according to the present invention comprises the steps of: forming an electronic device comprising a lower electrode, a capacitor insulating film using a ferroelectric, and an upper electrode on a semiconductor substrate; A step of depositing an interlayer insulating film on the semiconductor substrate, a step of forming a contact reaching the upper electrode in the interlayer insulating film, and a step of: Depositing a conductive barrier film by heating sputtering at a temperature, patterning the conductive barrier film in a region including the contact, and depositing a conductive film on the interlayer insulating film and the conductive barrier film; Forming a wiring by patterning the conductive film.

In the fourth method for manufacturing a semiconductor device according to the present invention, it is preferable that the conductive barrier film is formed using titanium nitride.

According to the fourth method for manufacturing a semiconductor device, after the contact is formed, the conductive barrier film is formed by heating and sputtering at a temperature exceeding the maximum temperature performed in a later step. Of the ferroelectric film can be reduced because the amount of water in the conductive barrier film does not increase and the amount of water in the conductive barrier film does not increase. In addition, by incorporating hydrogen or moisture generated from a film formed in an upper layer in a later step into the conductive barrier film, it is possible to reduce the possibility that hydrogen or moisture diffuses through the contact and damages the ferroelectric film.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a method for manufacturing a semiconductor device according to a first embodiment of the present invention will be described with reference to FIGS. 1 (a) to 1 (d) and FIGS. This will be described with reference to b).

First, as shown in FIG. 1A, a silicon oxide film 101 is deposited to a thickness of 1500 nm on a semiconductor substrate 100 on which elements such as MOS transistors are formed, and then flattened by resist etch back. Next, as shown in FIG. 1 (b), a platinum film is deposited to a thickness of 200 nm, a ferroelectric film made of strontium, bismuth, tantalum or the like is deposited to a thickness of 200 nm, and a platinum film is deposited to a thickness of 200 nm. A capacitance element including the electrode 102, the capacitance insulating film 103, and the upper electrode 104 is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere,
Damage to the ferroelectric film due to dry etching at the time of forming the capacitor is recovered.

Next, as shown in FIG. 1C, after a silicon oxide film 105 is deposited to a thickness of 500 nm, an upper electrode 104 is formed.
Is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to hydrogen or contact dry etching generated during deposition of the interlayer insulating film.

Next, as shown in FIG. 1D, for example, titanium nitride is formed to a thickness of 50 nm, and
After deposition, these are patterned to form contacts 10
6 is formed on a predetermined region including the conductive film 6 including a conductive barrier film 107 and a conductive hydrogen barrier film 108.

Next, as shown in FIG. 2A, a contact 109 to a MOS transistor or the like other than the capacitive element is formed. Next, as shown in FIG. 2B, from the lower layer, titanium 20 nm, titanium nitride 100 nm, aluminum 700
After depositing a metal film composed of four layers of 50 nm and 50 nm of titanium nitride, the wiring 110 is formed by patterning. After that, annealing is performed at 450 ° C. in an oxygen atmosphere,
It recovers damage to the ferroelectric film due to metal film deposition and wiring dry etching.

Thereafter, an interlayer film is deposited for multilayer wiring,
Contact formation, metal film deposition, and wiring formation are repeated, and finally a protective film is deposited and a pad opening is performed.

According to the first embodiment, the contact 10
6 is formed, and after annealing in an oxygen atmosphere at 800 ° C., the conductive hydrogen barrier film 1 made of titanium is formed on the contact 106.
Since 08 is formed, it is possible to reduce damage to the ferroelectric film that is transmitted through a contact generated in a later step.

Here, titanium is used for the conductive hydrogen barrier film 108, but a titanium aluminum alloy,
The same effect can be obtained by using another conductive film having low hydrogen permeability such as titanium aluminum nitride, aluminum nitride, and iridium oxide.

Since the conductive barrier film 107 having good adhesion to the upper electrode 104 and low reactivity is used under the conductive hydrogen barrier film 108, the conductive hydrogen barrier film 108
It is not necessary to consider the diffusion of the element into the upper electrode 104, the compatibility of the conductive hydrogen barrier film 108 with the upper electrode 104, and the compatibility such as adhesion. Specifically, for example, titanium diffuses in platinum and deteriorates the ferroelectric film. Alternatively, at high temperatures, aluminum reacts with platinum and deposits and expands. Therefore, using the conductive barrier film 107 under the conductive hydrogen barrier film 108 has an effect of increasing the degree of freedom of the process and increasing the margin.

(Second Embodiment) FIGS. 3A to 3D and FIGS. 4A to 4C show a semiconductor device and a method of manufacturing the same according to a second embodiment of the present invention. It will be described with reference to FIG.

First, as shown in FIG. 3A, a silicon oxide film 101 is deposited to a thickness of 1500 nm on a semiconductor substrate 100 on which elements such as MOS transistors are formed, and then flattened by resist etch back. Next, as shown in FIG. 3B, a platinum film is deposited in order of 200 nm, a ferroelectric film made of strontium, bismuth, tantalum or the like is deposited in order of 200 nm, and a platinum film is deposited in order of 200 nm. A capacitance element including the electrode 102, the capacitance insulating film 103, and the upper electrode 104 is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere,
Damage to the ferroelectric film due to dry etching at the time of forming the capacitor is recovered.

Next, as shown in FIG. 3C, after a silicon oxide film 105 is deposited to a thickness of 500 nm, an upper electrode 104 is formed.
Is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to hydrogen or contact dry etching generated during deposition of the interlayer insulating film.

Next, as shown in FIG. 3D, for example, titanium nitride is formed to a thickness of 50 nm, and
After depositing 00 nm, first, aluminum oxide is patterned in a region including the contact 106 to form an insulating hydrogen barrier film 111.

Next, as shown in FIG. 4A, for example, titanium nitride is deposited to a thickness of 50 nm and then patterned together with the previously deposited titanium nitride in a region wider than the insulating hydrogen barrier film 111 to form a conductive film. Barrier films 107 and 112 are formed. Thus, a stacked film including the conductive barrier film 107, the insulating hydrogen barrier film 111, and the conductive barrier film 112 is formed.

Next, as shown in FIG. 4B, a contact 109 to a MOS transistor or the like other than the capacitive element is formed. Next, as shown in FIG. 4C, titanium 20 nm, titanium nitride 100 nm, aluminum 700
After depositing a metal film composed of four layers of 50 nm and 50 nm of titanium nitride, the wiring 110 is formed by patterning. After that, annealing is performed at 450 ° C. in an oxygen atmosphere,
It recovers damage to the ferroelectric film due to metal film deposition and wiring dry etching.

Thereafter, an interlayer film is deposited for a multilayer wiring,
Contact formation, metal film deposition, and wiring formation are repeated, and finally a protective film is deposited and a pad opening is performed.

According to the second embodiment, the contact 10
6, and after annealing in an oxygen atmosphere at 800 ° C., the insulating hydrogen barrier film 111 made of aluminum oxide is formed on the contact 106, so that damage caused by passing through the contact generated in a later step can be reduced. .

Here, although aluminum oxide is used for the insulating hydrogen barrier film 111, tantalum oxide,
The same effect can be obtained by using another insulating film having low hydrogen permeability such as titanium oxide.

The conductive barrier films 107 and 112
Since the insulating hydrogen barrier film 111 is interposed between the stacked films, the insulating film can be used while being disposed on the contact. Therefore, the options of the hydrogen barrier film can be expanded as compared with the first embodiment.

Needless to say, the conductive hydrogen barrier film 108 described in the first embodiment may be used instead of the insulating hydrogen barrier film 111.

(Third Embodiment) A semiconductor device and a method of manufacturing the same according to a third embodiment of the present invention will be described below with reference to FIGS. 5 (a) to 5 (d) and FIGS. 6 (a) and 6 (b). This will be described with reference to FIG.

First, as shown in FIG. 5A, a silicon oxide film 101 is deposited to a thickness of 1500 nm on a semiconductor substrate 100 on which elements such as MOS transistors are formed, and then flattened by resist etch back. Next, as shown in FIG. 5B, a platinum film is deposited in order of 200 nm, a ferroelectric film made of strontium, bismuth, tantalum or the like is deposited in order of 200 nm, and a platinum film is deposited in order of 200 nm. A capacitance element including the electrode 102, the capacitance insulating film 103, and the upper electrode 104 is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere,
Damage to the ferroelectric film due to dry etching at the time of forming the capacitor is recovered.

Next, as shown in FIG. 5C, after depositing a silicon oxide film 105 to a thickness of 500 nm, the upper electrode 104 is formed.
Is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to hydrogen or contact dry etching generated during deposition of the interlayer insulating film.

Next, as shown in FIG. 5D, after depositing, for example, titanium nitride to a thickness of 50 nm and, for example, aluminum oxide to a thickness of 100 nm, these are patterned by taper etching using the same mask to form a contact 106. A conductive barrier film 1 on a predetermined region including
07 and an insulating hydrogen barrier film 111 having an area smaller than that of the conductive barrier film 107.

Next, as shown in FIG. 6A, a contact 109 to a MOS transistor or the like other than the capacitive element is formed. Next, as shown in FIG. 6B, titanium 20 nm, titanium nitride 100 nm, aluminum 700
After depositing a metal film composed of four layers of 50 nm and 50 nm of titanium nitride, the wiring 110 is formed by patterning. After that, annealing is performed at 450 ° C. in an oxygen atmosphere,
It recovers damage to the ferroelectric film due to metal film deposition and wiring dry etching.

Thereafter, an interlayer film is deposited for multilayer wiring,
Contact formation, metal film deposition, and wiring formation are repeated, and finally a protective film is deposited and a pad opening is performed.

According to the third embodiment, the contact 10
6, and after annealing in an oxygen atmosphere at 800 ° C., the insulating hydrogen barrier film 111 made of aluminum oxide is formed on the contact 106, so that damage caused by passing through the contact generated in a later step can be reduced. .

Here, although aluminum oxide is used for the insulating hydrogen barrier film 111, tantalum oxide,
The same effect can be obtained by using another insulating film having low hydrogen permeability such as titanium oxide.

The conductive barrier film 107 and the insulating hydrogen barrier film 111 are patterned by taper etching using the same mask, and the conductive barrier film 107 and the conductive Since the stacked film is formed of the insulating hydrogen barrier film 111 having a smaller area than the barrier film 107, the upper wiring 110 and the conductive barrier film 107 are in contact with each other, and the insulating hydrogen barrier film 111 is sandwiched between the two. Thus, the insulating film can be used while being arranged on the contact. Therefore, the options of the hydrogen barrier film can be expanded as compared with the first embodiment.

The conductive barrier film 107 is formed using the same mask.
In addition, since the insulating hydrogen barrier film 111 can be patterned, the number of mask steps can be reduced by one compared with the second embodiment, resulting in a low-cost semiconductor device.

As in the case of the second embodiment, the conductive hydrogen barrier film 108 described in the first embodiment may be used instead of the insulating hydrogen barrier film 111.

(Fourth Embodiment) FIGS. 7A to 7D and FIGS. 8A and 8B show a semiconductor device and a method of manufacturing the same according to a fourth embodiment of the present invention. It will be described with reference to FIG.

First, as shown in FIG. 7A, a silicon oxide film 101 is deposited to a thickness of 1500 nm on a semiconductor substrate 100 on which elements such as MOS transistors are formed, and then flattened by resist etch back. Next, as shown in FIG. 7B, a platinum film is deposited in order of 200 nm, a ferroelectric film made of strontium, bismuth, tantalum or the like is deposited in order of 200 nm, and a platinum film is deposited in order of 200 nm. A capacitance element including the electrode 102, the capacitance insulating film 103, and the upper electrode 104 is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere,
Damage to the ferroelectric film due to dry etching at the time of forming the capacitor is recovered.

Next, as shown in FIG. 7C, after a silicon oxide film 105 is deposited to a thickness of 500 nm, the upper electrode 104 is formed.
Is formed. After that, annealing is performed at 800 ° C. in an oxygen atmosphere to recover damage to the ferroelectric film due to hydrogen or contact dry etching generated during deposition of the interlayer insulating film.

Next, as shown in FIG. 7D, for example, titanium nitride is deposited to a thickness of 100 nm by heat sputtering at 450 ° C., and then patterned to form a conductive barrier film 113 on a predetermined region including the contact 106. To form

Next, as shown in FIG. 8A, a contact 109 to a MOS transistor or the like other than the capacitive element is formed. Next, as shown in FIG. 8B, titanium 20 nm, titanium nitride 100 nm, aluminum 700
After depositing a metal film composed of four layers of 50 nm and 50 nm of titanium nitride, the wiring 110 is formed by patterning. After that, annealing is performed at 450 ° C. in an oxygen atmosphere,
It recovers damage to the ferroelectric film due to metal film deposition and wiring dry etching.

After that, for multilayer wiring, an interlayer film is deposited,
Contact formation, metal film deposition, and wiring formation are repeated, and finally a protective film is deposited and a pad opening is performed.

According to the fourth embodiment, the contact 10
6 is formed, and after annealing at 800 ° C. in an oxygen atmosphere, a conductive barrier film 1 made of titanium nitride is formed on the contact 106.
Since 13 is formed by heating and sputtering at a temperature exceeding the maximum temperature performed in the subsequent step, the amount of moisture in the conductive barrier film is reduced, and no further moisture is generated by the heat treatment in the subsequent step. Therefore, damage to the ferroelectric film due to moisture in the conductive barrier film can be reduced. In addition, hydrogen or moisture is diffused through a contact by incorporating hydrogen or moisture generated from a film formed in an upper layer in a later step into the conductive barrier film,
Damage to the ferroelectric film can be reduced.

[0076]

According to the semiconductor device and the method of manufacturing the same of the present invention, after forming a contact on the upper electrode of an electronic device, a conductive hydrogen barrier film or an insulating hydrogen barrier film is provided so as to cover the contact, or By forming the conductive hydrogen barrier film covering the contact by heating sputtering at a temperature exceeding the maximum temperature performed in a later step, it is possible to reduce damage to the ferroelectric film caused by hydrogen or moisture through the contact, A highly reliable semiconductor device and a method for manufacturing the same can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a first embodiment of the present invention;

FIG. 2 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to the first embodiment of the present invention;

FIG. 3 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a second embodiment of the present invention;

FIG. 4 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a third embodiment of the present invention.

FIG. 7 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a fourth embodiment of the present invention.

FIG. 8 is a sectional view showing each step of a semiconductor device and a method of manufacturing the same according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view showing each step of a conventional semiconductor device and a method of manufacturing the same.

FIG. 10 is a sectional view showing each step of a conventional semiconductor device and a method of manufacturing the same.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 semiconductor substrate 101 silicon oxide film 102 lower electrode 103 capacitive insulating film 104 upper electrode 105 silicon oxide film 106 contact on upper electrode 107 conductive barrier film 108 conductive hydrogen barrier film 109 contact on semiconductor substrate 110 wiring 111 insulating hydrogen Barrier film 112 Conductive barrier film 113 Conductive barrier film formed by heating sputtering

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference)

Claims (16)

[Claims] 1. An electronic device comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode, and an interlayer insulating film formed on the semiconductor substrate including the electronic device. A film, a contact formed on the interlayer insulating film and reaching the upper electrode, a conductive barrier film formed on the interlayer insulating film and on the contact, and on the contact, and on the conductive barrier film. A conductive hydrogen barrier film formed, on the interlayer insulating film,
And a wiring formed on the conductive barrier film and the conductive hydrogen barrier film. 2. The semiconductor device according to claim 1, wherein the conductive hydrogen barrier film is made of at least one of titanium, titanium aluminum alloy, titanium aluminum nitride, aluminum nitride, and iridium oxide. 3. An electronic device comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode, and an interlayer insulating film formed on the semiconductor substrate including the electronic device. A film, a contact formed on the interlayer insulating film and reaching the upper electrode, a first conductive barrier film formed on the interlayer insulating film and on the contact, and on the contact; A hydrogen barrier film formed on a first predetermined region of the conductive barrier film, and a second predetermined region covering the hydrogen barrier film and wider than the first predetermined region of the first conductive barrier film. A semiconductor device comprising: a formed second conductive barrier film; and wirings formed on the interlayer insulating film and on the first and second conductive barrier films. 4. The semiconductor device according to claim 3, wherein the first and second conductive barrier films are made of titanium nitride. 5. An electronic device comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film using a ferroelectric, and an upper electrode, and an interlayer insulating film formed on the semiconductor substrate including the electronic device. A film, a contact formed on the interlayer insulating film and reaching the upper electrode, including a portion above the contact, a conductive barrier film formed on a first predetermined region of the interlayer insulating film, and including the portion above the contact A hydrogen barrier film formed on a second predetermined region narrower than the first predetermined region on a first predetermined region of the conductive barrier film, and a hydrogen barrier film formed on the interlayer insulating film; And a wiring formed on the conductive hydrogen barrier film. 6. The semiconductor device according to claim 1, wherein the conductive barrier film is made of titanium nitride. 7. The semiconductor device according to claim 3, wherein the hydrogen barrier film is made of at least one of aluminum oxide, tantalum oxide, and titanium oxide. 8. A capacitor insulating film using a ferroelectric, wherein a layered perovskite-type composite oxide containing strontium, bismuth, and tantalum, or lead, zirconium,
8. The semiconductor device according to claim 1, wherein the semiconductor device is made of one of a perovskite-type composite oxide containing titanium and titanium. 9. The method according to claim 1, wherein the electrode is made of one of platinum and a multilayer film containing platinum.
The semiconductor device according to any one of the above. 10. The semiconductor device according to claim 1, wherein the interlayer insulating film is made of one of a silicon oxide film and a silicon oxide film containing at least one of phosphorus and boron.
The semiconductor device according to any one of the above. 11. The semiconductor device according to claim 1, wherein the wiring comprises a multilayer film including titanium as a lowermost layer and at least aluminum as an upper layer. 12. A step of forming an electronic device including a lower electrode, a capacitor insulating film using a ferroelectric, and an upper electrode on a semiconductor substrate, and forming an interlayer insulating film on the semiconductor substrate including the electronic device. Depositing, and forming a contact reaching the upper electrode in the interlayer insulating film;
Depositing a conductive barrier film on the interlayer insulating film and on the contact, including on the contact, depositing a conductive hydrogen barrier film on the conductive barrier film, the conductive barrier film and Patterning the conductive hydrogen barrier film in a region including the contact; depositing a conductive film on the interlayer insulating film, on the conductive barrier film and on the conductive hydrogen barrier film; Forming a wiring by patterning the semiconductor device. 13. A step of forming an electronic device including a lower electrode, a capacitor insulating film using a ferroelectric and an upper electrode on a semiconductor substrate, and forming an interlayer insulating film on the semiconductor substrate including the electronic device. Depositing, and forming a contact reaching the upper electrode in the interlayer insulating film;
Depositing a first conductive barrier film on the interlayer insulating film and on the contact, depositing a hydrogen barrier film on the first conductive barrier film including on the contact, Patterning a barrier film in a first predetermined region including the contact; depositing a second conductive barrier film on the first conductive barrier film and the hydrogen barrier film; Patterning the first and second conductive barrier films in a second predetermined area that covers a predetermined area and is wider than the first predetermined area; and a step of patterning the first and second conductive barrier films on the interlayer insulating film and the first and second areas. A step of depositing a conductive film on the conductive barrier film, and a step of patterning the conductive film to form a wiring. 14. A step of forming an electronic device comprising a lower electrode, a capacitor insulating film using a ferroelectric and an upper electrode on a semiconductor substrate, and forming an interlayer insulating film on the semiconductor substrate including the electronic device. Depositing, and forming a contact reaching the upper electrode in the interlayer insulating film;
Depositing a conductive barrier film on the interlayer insulating film and on the contact, depositing a hydrogen barrier film on the conductive barrier film including on the contact, The barrier film is taper-etched in a region including the contact using the same mask, the conductive barrier film is formed in a first predetermined region, and the hydrogen barrier film is formed in a second predetermined region smaller than the first predetermined region. Patterning, a step of depositing a conductive film on the interlayer insulating film, the conductive barrier film and the hydrogen barrier film, and patterning the conductive film so as to cover at least the conductive barrier film. Forming a wiring. 15. A step of forming an electronic device including a lower electrode, a capacitor insulating film using a ferroelectric and an upper electrode on a semiconductor substrate, and forming an interlayer insulating film on the semiconductor substrate including the electronic device. Depositing, and forming a contact reaching the upper electrode in the interlayer insulating film;
Depositing a conductive barrier film on the interlayer insulating film and the contact by heat sputtering at a temperature exceeding a maximum temperature performed in a later step, and patterning the conductive barrier film in a region including the contact And a step of depositing a conductive film on the interlayer insulating film and the conductive barrier film; and a step of forming a wiring by patterning the conductive film. Production method. 16. The method according to claim 14, wherein the conductive barrier film is formed using titanium nitride.