JP2000164704A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which has a metal connection hole structure, wherein an aperture is formed in an etching stop film and an interlayer insulative film, in such a way as to penetrate the etching stop film and the interlayer insulating film and the etching stop film and the interlayer insulating film are electrically bonded together or an embedded metal wiring structure and a structure, wherein hydrogen diffused paths are ensured in the etching stop film and the interlayer insulating film by a simple method which suppresses increase of photolithographic processes, and a manufacturing method of the device. SOLUTION: As shown in Fig. (a), a film 4 having hydrogen barrier properties is formed on the upper part of a lower layer, in contact with the lower layer and after an interlayer insulating film 6 is formed on the film 4 in contact with the film 4 having these hydrogen barrier properties, an aperture 18 is formed in the films 6 and 4 in a form of penetrating both the film 6 and the film 4 which have hydrogen barrier properties. This aperture may be a hole to be used as a connection hole in a process subsequent to the formation of the aperture 18 or may be a groove to be a metal embedded wiring groove. Then, an in shown in Fig. (b), at least end surfaces 19 of the film 4, which has hydrogen barrier properties and is exposed at the formation of this aperture, are covered with a hydrogen diffused film and thereafter, the aperture is filled with a conductive material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having a metal connection hole structure or a buried metal wiring structure which penetrates an etching stop film and electrically connects layers, and is particularly performed in a final step of semiconductor device manufacturing. The present invention relates to a semiconductor device that secures a hydrogen diffusion path through which hydrogen reaches the inside of a multilayer wiring at the time of annealing with a forming gas to improve an annealing effect.

[0002]

2. Description of the Related Art In a final step of manufacturing a semiconductor device, an annealing process is performed in a forming gas atmosphere containing hydrogen gas for the purpose of inactivating crystal defects of silicon and stabilizing electrical characteristics of a semiconductor device. Have been done. By this annealing process, for example, hydrogen atoms are introduced directly at the interface between the gate oxide film and the silicon substrate, dangling bonds, which are silicon-oxygen bond defects, are eliminated, and fixed charges in the gate oxide film are neutralized. Is done.

However, using a self-aligned process,
In the case of forming a multilayer wiring on an LSI, it is necessary to form an etching stop film typified by a silicon nitride film on the LSI element region, and this etching stop film substantially serves as a hydrogen diffusion barrier. However, there has been a problem that effective annealing by forming gas cannot be performed.

A description will be given with reference to FIG. FIG.
FIG. 4 is a cross-sectional view of a general process in a case where a contact is formed in a self-alignment manner using a silicon nitride film when forming a contact electrically connected to a MOS transistor in AM.

As shown in FIG. 10A, a gate electrode 2 made of polysilicon and a side wall 5 of the gate electrode are formed on a silicon substrate 1 on which a MOS transistor is formed. A silicon oxide film 3, a silicon nitride film as an etching stopper film 4, and a BPSG film as an interlayer insulating film 6 are formed on the device. When etching is performed at a predetermined position of the BPSG film by a normal photolithography process,
An opening 7 is formed so as to stop at the etching stop film 4a.

Further, the etching stop film exposed at the bottom of the opening and the silicon oxide film under the etching stop film are also removed to form a connection hole and bury a metal such as tungsten, for example, as shown in FIG.
As shown in (b), the metal connection hole 8 is completed.

In the case where the metal connection hole is formed by using the ordinary process, the periphery of the metal contact is substantially covered with the silicon nitride film which functions as a hydrogen barrier.
During the annealing process, the hydrogen gas cannot reach the silicon substrate, and as a result, there is a problem that dangling bonds and the like cannot be eliminated.

Such a problem occurs not only in the case of a metal connection hole but also in a case where a multilayer wiring is formed by a buried metal wiring represented by, for example, a damascene wiring method.

For example, Japanese Unexamined Patent Publication No. 9-20942 discloses a multilayer wiring method for embedding a multilayer between layers with a copper alloy for interconnection. The periphery of the buried wiring is substantially not diffused with hydrogen and is blocked by a silicon nitride film. Therefore, as in the case shown in FIG. 10, there is a problem that effective annealing cannot be performed by the forming gas.

In order to solve such a problem, Japanese Unexamined Patent Publication No. 10-50964 attempts to solve the problem by forming a plug for diffusing hydrogen through the etching stop film. Certainly, this structure secures a hydrogen diffusion path, but requires a new photolithography step and mask step for opening holes in the nitride film, which increases costs and reduces the wiring density. Become.

[0011]

SUMMARY OF THE INVENTION The present invention has reduced the number of photolithography steps in a semiconductor device having a metal connection hole structure or a buried metal wiring structure which penetrates an etching stop film and electrically connects layers. An object of the present invention is to provide a semiconductor device having a hydrogen diffusion path secured by a simple method and a method for manufacturing the semiconductor device.

[0012]

According to the present invention, there is provided an interlayer insulating film on a semiconductor substrate, a film having a hydrogen barrier property formed in contact with a lower portion of the interlayer insulating film, A semiconductor device having a structure in which an opening formed to penetrate both films having a hydrogen barrier property is filled with a conductive material, and at least a film having a hydrogen barrier property exposed when the opening is formed. A hydrogen diffusion film is formed between the end surface of the substrate and a side wall of the structure in which the opening is filled with a conductive material in a subsequent step, and the hydrogen diffusion film allows hydrogen to flow to a lower portion of the film having the hydrogen barrier property. The present invention relates to a semiconductor device having a diffusion path secured.

The present invention further provides an interlayer insulating film, a lower nitride film formed in contact with a lower portion of the interlayer insulating film, and an upper nitride film formed in contact with an upper portion of the interlayer insulating film on a semiconductor substrate. And a metal wiring formed by filling a wiring groove formed so as to penetrate all of the interlayer insulating film, the lower nitride film, and the upper nitride film with a metal, and the entire surface of the side wall of the metal wiring Is covered with a hydrogen diffusion film, and the hydrogen diffusion film secures a hydrogen diffusion path to a lower portion of the lower nitride film.

Further, according to the present invention, an interlayer insulating film, a nitride film formed in contact with a lower portion of the interlayer insulating film on a semiconductor substrate, and a nitride film penetrating both the interlayer insulating film and the nitride film are provided. A method of manufacturing a semiconductor device having a conductive connection hole formed by filling a formed connection hole with a conductive material, comprising the steps of: forming an opening that penetrates the interlayer insulating film and reaches a nitride film; Removing the nitride film exposed at the bottom of the opening by etching including at least isotropic etching, forming a connection hole, and retreating the nitride film from a wall surface of the opening, and then performing the etching. Forming a hydrogen diffusion film on at least a portion of the stop film receded from the opening wall surface, and then forming a conductive connection hole by filling the connection hole formed with the hydrogen diffusion film with a conductive material. Half The method of manufacturing a body device.

Further, according to the present invention, at least a step of forming a lower nitride film on an arbitrary layer (referred to as a lower layer) formed on a semiconductor substrate, and forming an interlayer insulating film on the lower nitride film Forming an upper nitride film on the interlayer insulating film, forming a silicon oxide film on the upper nitride film, and then forming the silicon oxide film, the upper nitride film, the interlayer insulating film, Forming an opening penetrating through the lower nitride film and connecting to the lower layer; forming a hydrogen diffusion film inside the opening and over the entire surface of the silicon oxide film; Removing the hydrogen diffusion film formed at the bottom, exposing the lower layer, forming a connection hole, embedding a metal in the connection hole, and then polishing by CMP until the upper nitride film is exposed. And the hydrogen The method of manufacturing a semiconductor device including the step of completely removing the tapered portion of the Chimaku.

Further, according to the present invention, at least a step of forming a lower nitride film on an arbitrary layer (referred to as a lower layer) formed on a semiconductor substrate, and forming an interlayer insulating film on the lower nitride film A step of forming an upper nitride film on the interlayer insulating film, and a step of forming an opening penetrating the upper nitride film, the interlayer insulating film and the lower nitride film, and connecting to the lower layer. Forming a hydrogen diffusion film inside the opening and over the entire surface of the upper nitride film, and then removing at least the hydrogen diffusion film formed at the bottom of the opening to expose a lower layer and form a connection hole. And a step of embedding a metal in the connection hole, and then a step of polishing the upper nitride film by a CMP method to completely remove a tapered portion of the hydrogen diffusion film.

[0017]

FIG. 1B is an enlarged sectional view of a structure portion of a semiconductor device according to an embodiment of the present invention, in which a conductive material is embedded in a semiconductor device having a hydrogen diffusion path secured between layers. In this figure, the lower layer represents an arbitrary layer in the multilayer wiring structure of the semiconductor device, and may be a lowermost silicon substrate.

The structure shown in FIG. 1B is manufactured as follows. First, as shown in FIG. 1A, a film 4 having a hydrogen barrier property is formed on the lower layer in contact with the lower layer, and an interlayer insulating film 6 is formed on the film 4 having the hydrogen barrier property. After that, an opening 18 is formed so as to penetrate both the interlayer insulating film and the film having a hydrogen barrier property. This opening may be a hole to be a connection hole or a groove to be a metal embedded wiring in a subsequent step.
Next, at least the end face 19 of the film having a hydrogen barrier property exposed when the opening is formed is covered with a hydrogen diffusion film, and then filled with a conductive material. In this manner, a structure in which a hydrogen diffusion film is formed between the end face 19 and a side wall of the structure embedded with a conductive material in a subsequent step as shown in FIG. 1B is obtained. By adopting such a structure, a path for diffusing the hydrogen gas to the lower layer during the forming gas treatment is secured, and an effective annealing treatment with the forming gas becomes possible.

The structure 20 in which the conductive material is embedded may be a conductive connection hole typified by a contact plug or a metal wiring typified by a damascene wiring. For example, in a metal connection hole, tungsten or the like is used as a conductive material. For example, in a metal wiring, copper or a copper alloy is used as a conductive material.

When the structure 20 in which the conductive material is embedded is a conductive connection hole, for example, by isotropic etching,
Since the film 4 having the hydrogen barrier property can be receded, a hydrogen diffusion path can also be secured by forming a hydrogen diffusion film on the receded portion.

As the hydrogen diffusion film, a silicon oxide film, S
iON film, amorphous silicon film and polycrystalline silicon film.
It can be formed by VD, and is most preferable. The same material is used as a preferred example for the following hydrogen diffusion films.

The film having a hydrogen barrier property means a film which does not substantially diffuse hydrogen, and includes a nitride film such as Si ₃ N _{4 which} functions as an etching stop film when an opening is formed in an interlayer insulating film. Can be done. In the case of this film, the thickness is 10
It is known that when the temperature exceeds 0 °, hydrogen does not substantially diffuse.

As the interlayer insulating film, BP which is usually used
SG film, PSG film, SOG film, HSQ (Hydrogen Silicon)
A film in which hydrogen is substantially diffused, such as a sesqioxane film, a SiO ₂ film, or a SiON film, can be used as an interlayer insulating film (the same applies to the following interlayer insulating films).

FIGS. 2 to 4 are cross-sectional views of a semiconductor device manufactured by a process of forming metal connection holes in a self-aligned manner by using an etching stop film which is a film having a hydrogen barrier property.

In these figures, a lower layer represents an arbitrary layer in a multilayer wiring structure of a semiconductor device, and may be a lowermost silicon substrate. An etching stop film 4a is formed above the lower layer in contact with the lower layer, and an interlayer insulating film 6 is formed in contact with the etching stop film.

Further, a metal connection hole 8 is provided through the interlayer insulating film and the etching stop film, and is electrically connected to a lower layer and a wiring (not shown) formed above the interlayer insulating film. As an etching stop film, a silicon nitride film (Si ₃ N ₄ or SiN) is usually used. (The same applies to the following etching stopper film). When the thickness exceeds 100 °, hydrogen does not substantially diffuse and acts as a diffusion barrier.
In order to perform forming gas annealing effectively, it is necessary to provide a hydrogen diffusion film.

In FIG. 2, a hydrogen diffusion film 10 is formed at least between the side wall of the metal connection hole 8 and the etching stop film, and the metal connection hole is in contact with the interlayer insulating film 6 or the hydrogen diffusion film is formed. It has a structure in contact with the film. In other words, when the hydrogen diffusion film is formed by using a technique such as oxide film CVD, it is not necessary to cover the entire surface of the opening. As long as a hydrogen diffusion path is secured to the lower layer.

FIG. 3 shows that the hydrogen diffusion film 10 is
In which the entire surface of the side wall is covered, and a hydrogen diffusion path can be reliably ensured.

FIG. 4 shows that, after opening a connection hole penetrating through the interlayer insulating film and reaching the etching stop film, the etching stop film 4a is selectively retracted from the wall surface of the connection hole. It can be manufactured by forming a film. In such a structure, after a connection hole penetrating through the interlayer insulating film is opened, the etching stop film is etched by at least isotropic etching using an etching agent having a high etching rate. Can be selectively retracted. Examples of such isotropic etching include wet etching and isotropic dry etching.

The structure aimed at by the present invention may be any structure shown in FIGS. 2 to 4 as long as a hydrogen diffusion path is ensured, and may be a structure of a combination thereof.

FIG. 5A is a cross-sectional view of a semiconductor device manufactured by a process in which a wiring groove is formed in a self-aligned manner using a lower nitride film as an etching stopper and a metal is buried therein to form a metal wiring. .

In this figure, the lower layer represents an arbitrary layer in the multilayer wiring structure of the semiconductor device, and may be a lowermost silicon substrate. A lower nitride film 4b is formed on the lower layer in contact with the lower layer, an interlayer insulating film 6 is formed in contact with the lower nitride film, and an upper nitride film 13 is formed in contact with the interlayer insulating film. . A metal connection hole 8 is provided through the upper nitride film, the interlayer insulating film, and the lower nitride film to electrically connect the lower layer and a wiring (not shown) formed above the interlayer insulating film. As the upper nitride film, a silicon nitride film (Si ₃ N ₄ or Si
N) can be suitably used. In addition, there is an advantage that the process is not complicated by being shared with the lower nitride film.

It is preferable that the side wall of the metal wiring is covered with a hydrogen diffusion film as shown in FIG. Further, it is preferable that the thickness of the hydrogen diffusion film is constant in the vicinity 17 of the portion of the hydrogen diffusion film which is in contact with the upper nitride film. FIG.
(B) is an enlarged view of the vicinity 17 of a portion of the hydrogen diffusion film that is in contact with the upper nitride film. The constant thickness of the hydrogen diffusion film means that no taper is formed in the hydrogen diffusion film near the upper nitride film.

That is, when a silicon oxide film is formed as a hydrogen diffusion film by an oxide film CVD method, a taper is formed in the hydrogen diffusion film at the entrance of the wiring groove. When a metal is embedded in this state, as shown in FIG.
Since a metal layer is formed above the tapered portion, a sufficient hydrogen diffusion path cannot be secured. Therefore, as shown in FIG. 5B, it is necessary to form a hydrogen diffusion film so that a taper is not formed.

Although it has been described with reference to FIGS. 1 to 5 that a hydrogen diffusion path is ensured during forming gas annealing by forming a hydrogen diffusion film, it is necessary to obtain a substantial effect. The hydrogen diffusion film preferably has a thickness of 100 ° or more at the thinnest point,
A thickness of {-500} is optimal.

Example 1 As one embodiment of the manufacturing method of the present invention, a process for securing a hydrogen diffusion path in an SRAM structure will be described with reference to FIGS.

FIG. 6A shows that a gate electrode 2 made of polysilicon is formed on a silicon substrate 1 on which a MOS transistor is formed, and a sidewall 5 is formed on a side wall portion of the gate electrode. . An etching stop film 5a made of a silicon nitride film is formed in advance in the sidewall 5. The etching stop film in the side wall is provided for the purpose of preventing the side wall from being over-etched in the subsequent opening step, and is not an essential requirement of the present invention.

On these elements, a silicon oxide film 3, a silicon nitride film as an etching stopper film 4a, and a BPSG film as an interlayer insulating film 6 are formed.

As shown in FIG. 6B, an opening 7 is formed at a predetermined position of the BPSG film by using a usual photolithography process. At this time, the etching stop film functions as an etching stopper, and the etching stop film is exposed at the bottom of the opening.

Next, as shown in FIG. 6C, the etching stop film is selectively receded by etching including at least isotropic etching using an etching agent having a high etching rate. The recessed recessed portion 9 can be formed.

That is, after the opening 7 is formed, the etching stop film exposed at the bottom of the opening is removed by anisotropic etching, and the etching stop film is retreated by isotropic etching. After forming
A method of retreating the etching stop film only by isotropic etching is exemplified.

Next, as shown in FIG. 6D, after removing the etching stopper film, the silicon oxide film 3 formed in contact with the lower layer of the etching stopper film is removed by anisotropic etching. At this time, the etching stops at the portion of the etching stop film 5a in the sidewall.

Next, as shown in FIG. 7E, a hydrogen diffusion film 10 is formed. The formation method can be appropriately selected depending on the type of the hydrogen diffusion film such as a CVD method and a sputtering method. In this embodiment, as the simplest method, a silicon oxide film is formed by oxide film CVD. By this process,
A silicon oxide film is formed also on the recessed portion 9 formed in the step of FIG. 6C, and a silicon oxide film is formed also on the inner wall portion of the opening.

Next, as shown in FIG. 7 (f), the silicon oxide film formed at the bottom of the opening is removed by anisotropic etching to form a connection hole to be connected to the MOS transistor formed on the silicon substrate.

Next, as shown in FIG. 7G, a metal is buried to complete a metal connection hole. As a metal that fills the metal connection hole, for example, tungsten is a preferable metal. As shown in this figure, it is possible to embed metal before the tungsten is buried in a state where the wall surface of the connection hole is covered with a Ti / TiN film.

Further, as shown in FIG.
A film of TiN may be formed to form a wiring of AlCu or the like.

By the steps described above, a hydrogen diffusion path is secured by a simple method, and a sufficient annealing effect can be obtained.

(Embodiment 2) As one embodiment of the manufacturing method of the present invention, a process for securing a hydrogen diffusion path in a semiconductor device having a multilayer wiring structure by damascene wiring will be described with reference to FIGS.

FIG. 8A shows that a gate electrode 2 made of polysilicon is formed on a silicon substrate 1 on which a MOS transistor is formed, and a sidewall 5 is formed on a side wall of the gate electrode. Is shown. An interlayer insulating film 6 is formed above and in contact with the element region, and a metal connection hole penetrating the interlayer insulating film is provided. Hereinafter, a process of securing a hydrogen diffusion path when forming a damascene wiring electrically connected to the metal connection hole will be described.

Next, as shown in FIG. 8B, a lower nitride film 4b and a lower nitride film 4b are formed on the interlayer insulating film in which the metal connection holes 8 are formed.
An interlayer insulating film 6 and an upper nitride film 13 are sequentially formed. Further, a silicon oxide film 14 is formed on the upper nitride film. This silicon oxide film is for adjusting the height of the tapered portion of the hydrogen diffusion film formed in a later step, and forms the tapered portion at a position higher than the height of the upper surface portion of the final metal wiring. For this purpose, it is preferable that the thickness of the silicon oxide film is 500 ° or more.

Next, the upper nitride film, the interlayer insulating film, and the etching stop film are sequentially etched by anisotropic etching to form a wiring groove extending to the interlayer insulating film in which the metal connection hole as the lower layer is formed. Then, as shown in FIG. 8C, a hydrogen diffusion film 10 is formed in the opening and on the silicon oxide film 14. The hydrogen diffusion film has a tapered portion 1
5, the position of the tapered portion can be adjusted by adjusting the thickness of the silicon oxide film as shown in the figure.

Next, as shown in FIG. 8D, the hydrogen diffusion film formed at the bottom of the wiring groove is removed by anisotropic etching.

Next, as shown in FIG. 9E, a metal is embedded. This metal is copper commonly used in the damascene process,
It is also possible to use a copper alloy, tungsten, or the like, and there is no particular limitation.

Next, as shown in FIG. 9F, polishing is performed by a CMP method until a CMP polishing line (until the silicon oxide film 14 is completely removed and the upper nitride film appears). At this time, by setting the thickness of the silicon oxide film to 500 ° or more, since the tapered portion of the hydrogen diffusion film is located above the CMP polishing line, it is completely removed by the CMP polishing.
Therefore, in the vicinity of the portion of the hydrogen diffusion film that is in contact with the upper nitride film, the thickness of the hydrogen diffusion film is kept constant, and a hydrogen diffusion path is secured.

Next, as shown in FIGS. 9 (g) and 9 (h), the above steps are repeated to complete a multilayer wiring.

In the above example, the silicon oxide film is used for adjusting the taper position of the hydrogen diffusion film. However, instead of forming this silicon oxide film, the upper nitride film may be formed to a thickness of 500 ° or more. The object of the invention can be achieved.
In this case, as shown in FIG.
Although it is difficult to specify the polishing line, there is an advantage that the etching step for forming the opening can be reduced in FIG.

By the steps described above, a hydrogen diffusion path is secured by a simple method, and a sufficient annealing effect can be obtained.

[0058]

As described above in detail, according to the present invention, in a semiconductor device having a metal connection hole structure or a buried metal wiring structure penetrating an etching stop film and electrically connecting layers, a metal connection is provided. When the hole structure or the metal wiring structure is formed, a hydrogen diffusion path can be secured at the same time. By adopting such a structure, a hydrogen diffusion path can be secured by a simple process in which an increase in the photolithography process is suppressed, and the effect of annealing the forming gas can be improved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a structure portion of a semiconductor device according to an embodiment of the present invention in which a conductive material is embedded in a semiconductor device having a hydrogen diffusion path secured between layers.

FIG. 2 is an enlarged cross-sectional view of a metal connection hole of a semiconductor device having a hydrogen diffusion path secured between layers according to an embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a metal connection hole portion of a semiconductor device having a hydrogen diffusion path secured between layers according to an embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view of a metal connection hole portion of a semiconductor device in which a hydrogen diffusion path is secured between layers of a multilayer wiring according to an embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a metal connection hole portion of a semiconductor device in which a hydrogen diffusion path is secured between layers of a multilayer wiring according to an embodiment of the present invention.

FIG. 6 shows an embodiment of a production method according to the present invention,
FIG. 13 is a process cross-sectional view showing a process in a preceding stage of securing a hydrogen diffusion path in the M structure.

FIG. 7 shows an embodiment of the manufacturing method according to the present invention,
FIG. 10 is a process cross-sectional view showing a subsequent process of securing a hydrogen diffusion path in a semiconductor device having an M structure.

FIG. 8 is a cross-sectional view showing a step in a preceding stage of securing a hydrogen diffusion path in a semiconductor device having a multilayer wiring structure using damascene wiring as one embodiment of the manufacturing method of the present invention.

FIG. 9 is a process cross-sectional view showing a subsequent process of securing a hydrogen diffusion path in a semiconductor device having a multilayer wiring structure using damascene wiring as an embodiment of the manufacturing method of the present invention.

FIG. 10 is a process cross-sectional view showing a conventional process in a case where a contact plug electrically connected to a MOS transistor formed on a silicon substrate is formed in a self-aligned manner using a silicon nitride film.

[Explanation of symbols]

Reference Signs List 1 silicon substrate 2 gate electrode 3 silicon oxide film 4 film having hydrogen barrier property 4a etching stop film 4b lower nitride film 5 side wall 5a etching stop film formed on side wall 6 interlayer insulating film 7 opening 8 metal connection hole 8a Tungsten 8b Ti / TiN film 9 Recessed portion 10 Hydrogen diffusion film 11 TiN film 12 AlCu 13 Upper nitride film 14 Silicon oxide film for adjusting taper position of hydrogen diffusion film 15 Hydrogen diffusion film taper portion 16 Embedded metal 17 CMP of hydrogen diffusion film Near the portion in contact with the film 18 Opening 19 End face of the film having hydrogen barrier properties exposed when forming the opening 20 Structure in which the opening is filled with a conductive material

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4M104 BB01 BB14 BB18 CC01 DD04 DD07 DD08 DD09 DD10 DD16 DD17 DD18 DD19 DD20 EE01 EE12 FF13 FF21 FF22 FF24 5F033 HH11 HH12 HH19 JJ04 JJ05 JJ18 JJ19 KK10 NN01 QQ09 QQ16 QQ18 QQ19 QQ25 QQ33 QQ37 QQ48 QQ73 RR04 RR06 RR08 RR09 RR14 RR15 SS11 TT01 TT06 TT07 TT08 VV06 WW02

Claims (27)

[Claims] 1. An interlayer insulating film, a film having a hydrogen barrier property formed in contact with a lower portion of the interlayer insulating film, and both the interlayer insulating film and the film having a hydrogen barrier property on a semiconductor substrate. A semiconductor device having a structure in which an opening formed to penetrate through the opening is filled with a conductive material, at least an end face of a film having a hydrogen barrier property exposed when the opening is formed, and A hydrogen diffusion film is formed between the opening and the side wall of the structure in which the conductive material is buried, and the hydrogen diffusion film secures a hydrogen diffusion path to a lower portion of the film having the hydrogen barrier property. A semiconductor device characterized by the above-mentioned. 2. The semiconductor device according to claim 1, wherein the entire surface of the side wall of the structure in which the opening is filled with a conductive material is covered with a hydrogen diffusion film. 3. The semiconductor device according to claim 1, wherein the film having a hydrogen barrier property is a nitride film. 4. The semiconductor device according to claim ₃ , wherein said nitride film is a Si ₃ N ₄ film. 5. The semiconductor device according to claim 1, wherein the structure filled with the conductive material is a conductive connection hole. 6. The hydrogen barrier film according to claim 5, wherein the hydrogen barrier film is recessed from a wall surface of the conductive connection hole, and a hydrogen diffusion film is formed at least in the recessed portion. Semiconductor device. 7. The semiconductor device according to claim 5, wherein said conductive material is tungsten. 8. The semiconductor device according to claim 1, wherein the structure in which the conductive material is buried is a metal wiring. 9. The semiconductor device according to claim 8, wherein said conductive material is copper or a copper alloy. 10. An interlayer insulating film, a lower nitride film formed in contact with a lower portion of the interlayer insulating film, and an upper nitride film formed in contact with an upper portion of the interlayer insulating film on a semiconductor substrate.
A semiconductor device having a metal wiring formed by filling a wiring groove formed so as to penetrate all of the interlayer insulating film, the lower nitride film, and the upper nitride film with a metal, wherein the entire surface of the side wall of the metal wiring is hydrogen. A semiconductor device, wherein the semiconductor device is covered with a diffusion film, and the hydrogen diffusion film secures a hydrogen diffusion path to a lower portion of the lower nitride film. 11. The semiconductor device according to claim 10, wherein the thickness of the hydrogen diffusion film is constant near a portion of the hydrogen diffusion film which is in contact with the upper nitride film. 12. The semiconductor device according to claim 10, wherein said upper nitride film and said lower nitride film are Si ₃ N ₄ films. 13. The semiconductor device according to claim 10, wherein the metal filling the connection hole is copper or a copper alloy. 14. The method according to claim 1, wherein the interlayer insulating film is a BPSG film, a PS
G film, SOG film, HSQ film, SiO ₂ film or SiON
14. The semiconductor device according to claim 1, wherein the semiconductor device is any one of films. 15. The hydrogen diffusion film may be a SiO ₂ film, a Si
15. The semiconductor device according to claim 1, wherein the semiconductor device is an ON film, an amorphous Si film, or a polycrystalline Si film. 16. A semiconductor device, comprising: an interlayer insulating film; a nitride film formed in contact with a lower portion of the interlayer insulating film; and a film penetrating both the interlayer insulating film and the nitride film. A method for manufacturing a semiconductor device having a conductive connection hole formed by filling a connection hole with a conductive material, comprising: forming an opening penetrating the interlayer insulating film and reaching a nitride film; Removing the nitride film exposed at the bottom of the hole by etching including at least isotropic etching to form a connection hole, and retreating the nitride film from the wall surface of the opening; A step of forming a hydrogen diffusion film at least in a portion receded from an opening wall surface, and then a step of forming a conductive connection hole by filling the connection hole in which the hydrogen diffusion film is formed with a conductive material. Manufacture Method. 17. The method according to claim 16, wherein the nitride film is a Si ₃ N ₄ film. 18. The method for manufacturing a semiconductor device according to claim 16, wherein the metal filling said connection hole is tungsten. 19. A step of forming a lower nitride film on at least an arbitrary layer (referred to as a lower layer) formed on a semiconductor substrate; and a step of forming an interlayer insulating film on the lower nitride film. Forming an upper nitride film on the interlayer insulating film, forming a silicon oxide film on the upper nitride film, and then forming the silicon oxide film, the upper nitride film, the interlayer insulating film, and the lower nitride film. Forming an opening penetrating a film and connecting to the lower layer; forming a hydrogen diffusion film inside the opening and over the entire surface of the silicon oxide film; and then forming at least a bottom portion of the opening. Removing the removed hydrogen diffusion film, exposing the lower layer and forming a connection hole, embedding a metal in the connection hole, and then performing CMP.
Polishing until the upper nitride film is exposed by a method, and completely removing a tapered portion of the hydrogen diffusion film. 20. In the step of forming the silicon oxide film, the silicon oxide film is formed to a sufficient thickness so that a tapered portion of a hydrogen diffusion film formed in a subsequent step is higher than the final height of the metal wiring. 20. The method according to claim 19, wherein the semiconductor device is formed. 21. The semiconductor device according to claim 1, wherein the thickness of the silicon oxide film is 500
21. The method for manufacturing a semiconductor device according to claim 19, wherein the number is not less than Å. 22. A step of forming a lower nitride film on at least an arbitrary layer (referred to as a lower layer) formed on the semiconductor substrate; and a step of forming an interlayer insulating film on the lower nitride film. Forming an upper nitride film on the interlayer insulating film, then forming an opening penetrating through the upper nitride film, the interlayer insulating film and the lower nitride film, and connecting to the lower layer; Forming a hydrogen diffusion film inside and over the entire surface of the upper nitride film, and then removing at least the hydrogen diffusion film formed at the bottom of the opening, exposing the lower layer,
A step of forming a connection hole, a step of embedding a metal in the connection hole, and a step of polishing the upper nitride film by a CMP method to completely remove a tapered portion of the hydrogen diffusion film. Production method. 23. In the step of forming the upper nitride film, the upper nitride film is formed to have a sufficient thickness so that a tapered portion of a hydrogen diffusion film formed in a subsequent step is higher than the final metal wiring height. The method for manufacturing a semiconductor device according to claim 22, wherein the semiconductor device is formed. 24. The method according to claim 22, wherein a thickness of the upper nitride film is 500 ° or more. 25. The semiconductor device according to claim 19, wherein the upper nitride film and the lower nitride film are Si ₃ N ₄ films.
5. The semiconductor device according to any one of 4. 26. The method according to claim 26, wherein the interlayer insulating film is a BPSG film, a PS
G film, SOG film, HSQ film, SiO ₂ film or SiON
26. The film according to claim 16, which is one of films.
The semiconductor device according to any one of the above. 27. The hydrogen diffusion film is made of an SiO ₂ film, a Si
27. The semiconductor device according to claim 16, wherein the semiconductor device is an ON film, an amorphous Si film, or a polycrystalline Si film.