JP2010278197A - Semiconductor memory device and manufacturing method thereof - Google Patents

Abstract

A semiconductor memory device and a method of manufacturing the semiconductor memory device are provided that can reliably prevent a capacitor insulating film made of a ferroelectric or high dielectric of a capacitor from being deteriorated by hydrogen generated from a hydrogen barrier film.
A semiconductor memory device includes a capacitor having a capacitive insulating film made of a ferroelectric or a high dielectric formed on a semiconductor substrate, and a first hydrogen formed on the lower side of the capacitor. And a barrier film 15. The first hydrogen barrier film 15 is made of silicon nitride containing fluorine.
[Selection] Figure 1

Description

  The present invention relates to a semiconductor memory device and a manufacturing method thereof, and more particularly to a semiconductor memory device having a capacitor using a ferroelectric or a high dielectric material for a capacitor insulating film and a manufacturing method thereof.

  Semiconductor memory devices using ferroelectrics or high dielectrics for capacitive insulating films have remanent polarization due to hysteresis characteristics and high relative permittivity, so DRAM (dynamic random access memory) is the leading volatility. The semiconductor memory device can be replaced with a semiconductor memory device having a capacitor using a capacitor insulating film made of silicon oxide or silicon nitride in the field of a semiconductor memory device or a flash memory.

However, a ferroelectric substance or a high dielectric substance is a metal oxide whose crystal structure itself determines its physical characteristics, and therefore has a great influence of the reduction action by hydrogen. On the other hand, a process for forming a metal oxide semiconductor (MOS) transistor, a process for forming a multilayer wiring, a process for forming a protective film, and the like include a silane (SiH ₄ ) gas containing hydrogen atoms as well as a hydrogen (H ₂ ) gas, a resist material, Many processes using water (moisture) or the like are included, and there is a concern about deterioration of physical properties of the ferroelectric or high dielectric.

  Therefore, in recent years, a technique has been proposed in which a hydrogen barrier layer is provided around a capacitor, and the capacitor is covered by a hydrogen barrier layer for each capacitor or a plurality of capacitors as a unit. (For example, see Patent Document 1).

  Hereinafter, a semiconductor memory device having a capacitor using a capacitor insulating film using a ferroelectric according to a conventional example described in Patent Document 1 will be described with reference to FIG. As shown in FIG. 6, a MOS transistor 2 is formed on a semiconductor substrate 1, and the MOS transistor 2 is covered with an interlayer insulating film 3 whose upper surface is flattened. A ferroelectric capacitor comprising a lower electrode 7, a ferroelectric film 8, and an upper electrode 9 is formed on the interlayer insulating film 3, and the periphery of the ferroelectric capacitor is surrounded by hydrogen barrier films 4, 5, 5A, 6 and 10 cover the upper side, the side and the lower side.

  Thus, in the conventional semiconductor memory device, the upper, side and lower sides of the ferroelectric capacitor are covered with a plurality of hydrogen barrier films. Therefore, in the semiconductor formation process after forming the capacitor, the capacitor is in a hydrogen atmosphere. Since the ferroelectric film is not reduced even when exposed to the above, a highly reliable capacitor can be obtained.

Japanese Patent No. 3654585

International Symposium on Application of Ferroelectrics (ISAF) 2007, 29B-FR3-I2, Development of Integration Technology of Stacked Capacitors Using SrBi2Ta2O9 Thin Films Applicable to 0.25μm FeRAM, K. Ashikaga, T. Yamanobe, K. Takaya, S. Ozawa, T. Hayashi and Y. Kobayashi (Oki Electric)

  However, the inventor of the present application has conducted various studies on the conventional semiconductor memory device, and as a result, the semiconductor memory having a capacitive insulating film using a ferroelectric material even though the periphery is covered with a hydrogen barrier layer. It has been confirmed that the electrical characteristics of the equipment deteriorate.

  Therefore, the inventor of the present application investigated the cause of this deterioration, and the hydrogen contained in the hydrogen barrier film itself was desorbed by the heat treatment during the semiconductor manufacturing process or during the assembly and sealing process after the completion of the semiconductor memory device. It has been concluded that reducing the film deteriorates the electrical characteristics of the ferroelectric capacitor.

  FIG. 6 schematically shows a model of deterioration of the ferroelectric film estimated by the inventor of the present application. As shown in FIG. 6, hydrogen generated from the hydrogen barrier films 5 and 10 made of silicon nitride (SiN) reaches the ferroelectric film 8 through the path indicated by the arrow, and the hydrogen that reaches the ferroelectric film 8 is strong. By reducing the dielectric, the ferroelectricity of the ferroelectric is lost, and the function as a memory is lost.

  In view of the above problems, an object of the present invention is to reliably prevent a capacitor insulating film made of a ferroelectric or high dielectric of a capacitor from being deteriorated by hydrogen generated from a hydrogen barrier film. To do.

  In order to achieve the above object, according to the present invention, a semiconductor memory device has a structure in which hydrogen inevitably contained in a hydrogen barrier film is replaced with fluorine during a manufacturing process.

  Specifically, a semiconductor memory device according to the present invention includes a capacitor having a capacitive insulating film made of a ferroelectric or high dielectric formed on a semiconductor substrate, and a hydrogen barrier film formed around the capacitor. And at least a part of the hydrogen barrier film contains fluorine.

  According to the semiconductor memory device of the present invention, since at least a part of the hydrogen barrier film formed around the capacitor contains fluorine, the reduction of the capacitive insulating film due to desorbed hydrogen from the hydrogen barrier film is significantly reduced. As a result, deterioration of the capacitor insulating film due to hydrogen can be reliably prevented, so that a high-quality semiconductor memory device having excellent electrical characteristics (operation characteristics) can be obtained.

  In the semiconductor memory device of the present invention, the hydrogen barrier film preferably has a hydrogen group substituted with a fluorine group. Here, a bonded state terminated with -H, such as Si-H, is defined as a hydrogen group, and similarly, a bonded state terminated with -F, such as Si-F, is defined as a fluorine group. To do.

  In the semiconductor memory device of the present invention, the hydrogen barrier film may be a fluorine-containing silicon nitride film.

In this case, the fluorine bonding amount in the fluorine-containing silicon nitride film is preferably larger than 7 × 10 ²¹ pieces / cm ³ .

  In this case, the film thickness of the fluorine-containing silicon nitride film may be 10 nm or more.

  In the semiconductor memory device of the present invention, a plurality of capacitors may be formed on the semiconductor substrate, and the hydrogen barrier film may cover the periphery of each capacitor of the plurality of capacitors.

  In the semiconductor memory device of the present invention, a plurality of capacitors may be formed on the semiconductor substrate, and the hydrogen barrier film may cover the periphery of every two or more capacitors of the plurality of capacitors.

  A method of manufacturing a semiconductor memory device according to the present invention includes a step of forming a capacitor made of a ferroelectric or a high dielectric on a semiconductor substrate, and a step of forming a hydrogen barrier film around the capacitor. In the step of forming the film, at least part of the hydrogen barrier film includes a first source gas having a bond of silicon and hydrogen, a second source gas having a bond of nitrogen and hydrogen, and a third source gas containing fluorine. A fluorine-containing silicon nitride film is formed by reacting a source gas.

  According to the method for manufacturing a semiconductor memory device of the present invention, a hydrogen barrier film, at least part of which is made of fluorine-containing silicon nitride, is formed around the capacitor. For this reason, the content of hydrogen remaining in the hydrogen barrier film being manufactured is reduced, and the reduction of the capacitive insulating film due to desorbed hydrogen from the hydrogen barrier film is remarkably reduced. It can be surely prevented. As a result, a high-quality semiconductor memory device having excellent electrical characteristics (operation characteristics) can be obtained.

  In the method of manufacturing a semiconductor memory device according to the present invention, in the step of forming the hydrogen barrier film, the fluorine-containing silicon nitride film includes a bond between silicon and hydrogen, a bond between nitrogen and hydrogen, and a bond between silicon and fluorine and nitrogen. It may be formed by being substituted with a bond with fluorine.

  In the method of manufacturing a semiconductor memory device of the present invention, in the step of forming the hydrogen barrier film, the third source gas includes silicon fluoride, sulfur fluoride, methyl fluoride, arsenic fluoride, phosphorus fluoride, fluoride fluoride. At least one gas selected from boron, fluorocarbon, and nitrogen fluoride can be used.

In the method for manufacturing a semiconductor memory device of the present invention, the amount of fluorine bonding in the fluorine-containing silicon nitride film is preferably larger than 7 × 10 ²¹ pieces / cm ³ .

  According to the semiconductor memory device and the manufacturing method thereof according to the present invention, the reduction of the capacitive insulating film due to the desorbed hydrogen from the hydrogen barrier film is remarkably reduced, and the deterioration of the capacitive insulating film due to hydrogen can be surely prevented. A quality semiconductor memory device can be realized.

It is sectional drawing of the principal part which shows the semiconductor memory device which concerns on one Embodiment of this invention. Effect of improving polarization amount and fluorine bond amount of silicon nitride film when hydrogen barrier film using silicon nitride formed in semiconductor memory device according to one embodiment of the present invention is normalized to 1 It is a graph which shows the relationship. (A)-(c) is sectional drawing of the order of a process which shows the manufacturing method of the semiconductor memory device concerning one Embodiment of this invention. It is typical sectional drawing which shows an example of the film-forming apparatus which forms the hydrogen barrier film which consists of fluorine-containing silicon nitride concerning one Embodiment of this invention. ₄ is a graph showing the relationship between the fluorine bond amount of a silicon nitride film formed in the semiconductor memory device according to the embodiment of the present invention and the flow rate of SiF ₄ that is a source gas of the silicon nitride film. It is sectional drawing of the principal part which shows the semiconductor memory device concerning a prior art example.

(One embodiment)
A semiconductor memory device according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, in the semiconductor memory device according to this embodiment, a MOS transistor 12 is formed in a memory region of a semiconductor substrate 11 made of, for example, silicon (Si). A bit line 13 for reading memory data is connected to the first impurity diffusion layer 12 a in the MOS transistor 12 via the MOS transistor 12.

  In the memory region on the semiconductor substrate 11, a first interlayer insulating film 14 made of, for example, BPSG (boro-phospho-silicate glass) is formed so as to cover the MOS transistor 12 with the upper surface thereof being flattened. . A first hydrogen barrier film 15 made of fluorine-containing silicon nitride is formed on the first interlayer insulating film 14. A contact plug 16 is formed in the first interlayer insulating film 14 and the first hydrogen barrier film 15 so as to penetrate the first interlayer insulating film 14 and the first hydrogen barrier film 15 and to be electrically connected to the second impurity diffusion layer 12b of the MOS transistor 12.

  On the first hydrogen barrier film 15, a capacitor 20 in which a lower electrode 17, a capacitor insulating film 18 including a ferroelectric or high dielectric, and an upper electrode 19 are sequentially stacked so as to be connected to the contact plug 16. Is formed. A second hydrogen barrier film 21 made of, for example, silicon nitride (SiN) or titanium aluminum nitride (TiAlN) is formed on the first hydrogen barrier film 15 so as to cover the upper surface and side surfaces of the capacitor 20. Yes. A second interlayer insulating film 22 made of silicon oxide such as BPSG is formed on the second hydrogen barrier film 22.

  As a feature of the present embodiment, as the first hydrogen barrier film 15 provided on the lower side of the capacitor 20 (lower electrode 17), fluorine (F) is contained in silicon nitride (SiN), and hydrogen groups in the silicon nitride are contained. A fluorine-containing silicon nitride (SiNF) film in which (—H) is replaced with a fluorine group (—F) is used. Although not shown, a plurality of MOS transistors 12 and capacitors 20 are formed on the semiconductor substrate 11, and the first hydrogen barrier film 15 is provided for each capacitor 20. It may be provided for each block including a plurality of capacitors 20.

  The fluorine-containing silicon nitride film according to the present embodiment is formed, for example, under the film formation conditions shown in [Table 1].

図２は、窒化シリコンを第１の水素バリア膜に用いた場合の該第１の水素バリア膜の分極量を１と規格化したときの、フッ素含有窒化シリコン膜の分極量の向上効果とフッ素含有窒化シリコン膜中のフッ素結合量（Ｓｉ−Ｆ及びＮ−Ｆの総数）（個／ｃｍ^３）との関係を示している。ここで、比較例として、フッ素を含まない窒化シリコン（ＳｉＮ）膜の成膜条件を、シラン（ＳｉＨ_４）の流量を３０ｍｌ／ｍｉｎ（標準状態）、アンモニア（ＮＨ_３）の流量を３７００ｍｌ／ｍｉｎ（標準状態）、及び窒素（Ｎ_２）の流量を３０００ｍｌ／ｍｉｎ（標準状態）とし、成膜時の圧力を３６．５ｋＰａとし、成膜温度を８００℃とし、膜厚を２０ｎｍとしている。なお、縦軸は任意単位（ａ．ｕ．）である。

FIG. 2 shows the effect of improving the polarization amount of the fluorine-containing silicon nitride film when the polarization amount of the first hydrogen barrier film is normalized to 1 when silicon nitride is used for the first hydrogen barrier film. The relationship with the amount of fluorine bonds (total number of Si—F and N—F) (pieces / cm ³ ) in the silicon nitride film is shown. Here, as a comparative example, the film formation conditions of a silicon nitride (SiN) film not containing fluorine are as follows: the flow rate of silane (SiH ₄ ) is 30 ml / min (standard state), and the flow rate of ammonia (NH ₃ ) is 3700 ml / min. The flow rate of nitrogen (N ₂ ) is 3000 ml / min (standard state), the pressure during film formation is 36.5 kPa, the film formation temperature is 800 ° C., and the film thickness is 20 nm. The vertical axis is an arbitrary unit (au).

As can be seen from FIG. 2, by replacing hydrogen in the fluorine-containing silicon nitride film with fluorine and increasing the amount of fluorine bonds in the film to more than 7 × 10 ²¹ pieces / cm ³ , the polarization amount of the capacitive insulating film 18 It has been confirmed that the improvement effect of 1 can be made larger than 1, that is, the polarization characteristics of a ferroelectric or the like can be improved.

Incidentally, the amount of hydrogen bonds (total number of Si—H and N—H) in the silicon nitride film not containing fluorine as a comparative example is 3 × 10 ²² / cm ³ . Therefore, when the fluorine bond amount in the fluorine-containing silicon nitride film is 7 × 10 ²¹ pieces / cm ³ , the hydrogen bond amount in the fluorine-containing silicon nitride film is 3 × 10 ²² pieces / cm ³ to 6 × 10 ²¹ pieces. / Cm ³ , and the difference is considered to correspond to the fluorine bond amount. Here, the Fourier transform infrared spectroscopy (FT-IR) method is used for the measurement of the fluorine bond amount and the hydrogen bond amount.

  Hereinafter, a method for manufacturing the semiconductor memory device according to this embodiment configured as described above will be described with reference to FIGS.

  First, as shown in FIG. 3A, an STI (shallow trench isolation) isolation region (not shown) for dividing a plurality of active regions is formed on the semiconductor substrate 11. Thereafter, a gate insulating film and a gate electrode are sequentially stacked on the active region of the semiconductor substrate 11. Thereafter, impurity ions are ion-implanted into the upper portion of the semiconductor substrate 11 using the gate electrode or the like as a mask to form the first impurity diffusion layer 12a and the second impurity diffusion layer 12b in regions on both sides of the gate electrode. Thus, the MOS transistor 12 is obtained. Subsequently, a bit line 13 for reading data from a memory cell is formed on the semiconductor substrate 11 so as to be connected to the first impurity diffusion layer 12 a of the MOS transistor 12. Thereafter, a first interlayer insulating film 14 made of BPSG is formed on the semiconductor substrate 11 so as to cover the transistor 12 and the bit line 13, and then the upper surface of the first interlayer insulating film 14 is formed on the chemical mechanical layer. Planarization is performed by polishing (CMP).

  Next, as shown in FIG. 3B, the first hydrogen barrier film 15 made of fluorine-containing silicon nitride is formed to have a film thickness of, for example, at least 10 nm, and in this case, about 20 nm. Details of the method for forming the first hydrogen barrier film 15 will be described later.

Next, as shown in FIG. 3C, the first hydrogen barrier film 15 and the first interlayer insulating film 14 that are formed are connected to the second impurity diffusion layer 12 b of the MOS transistor 12. A contact plug 16 is formed. Here, a barrier film having a hydrogen barrier property may be formed on the side surface of the contact plug 16. Thereafter, on the first hydrogen barrier film 15, a lower electrode 17, a capacitor insulating film 18 including a ferroelectric or high dielectric, and an upper electrode 19 are sequentially stacked so as to be connected to the upper surface of the contact plug 16. Thus, the capacitor 20 is formed. Here, platinum (Pt), iridium (Ir), or the like can be used for the lower electrode 17 and the upper electrode 19. Further, a barrier film having a hydrogen barrier property may be provided in the lowermost layer connected to the contact plug 16 in the lower electrode 17. For the capacitor insulating film 18, a known ferroelectric material such as a metal oxide having a perovskite structure can be used, and a high dielectric material such as tantalum pentoxide (Ta ₂ O ₅ ) can be used. . Thereafter, a second hydrogen barrier film 21 is formed on the first hydrogen barrier film 15 so as to cover the upper surface and side surfaces of the capacitor 20. Subsequently, a second interlayer insulating film 22 made of BPSG or the like is formed so as to cover the second hydrogen barrier film 21.

  Here, a method of forming the first hydrogen barrier film 15 made of fluorine-containing silicon nitride shown in FIG.

  First, a film forming apparatus for forming the first barrier film 15 is schematically shown in FIG. As shown in FIG. 4, the film forming apparatus includes a gas introduction port 31 a and a gas exhaust port 31 b, and includes a chamber 31 made of quartz that can be decompressed, and the semiconductor substrate 11 is disposed inside the chamber 31. Is provided. A plurality of heating lamps 33 for heating the semiconductor substrate 11 to a predetermined temperature are provided around the chamber 31. A predetermined source gas is introduced into the chamber 31 from the gas inlet 31a, and the reacted gas after film formation is discharged from the gas exhaust port 16. 4 shows a film forming apparatus capable of performing lamp heating type chemical vapor deposition, but the present invention is not limited to this, and a heater heating type film forming apparatus in which a heater is incorporated in the susceptor 32 or a heating lamp is shown. A hot wall type heater heating film forming apparatus in which 33 is replaced with a heater may be used.

  Using the film forming apparatus as described above, first, the semiconductor substrate 11 on which the first interlayer insulating film (not shown) is formed is placed on the susceptor 32. At this time, the semiconductor substrate 11 is heated to about 800 ° C. by the heating lamp 33.

Subsequently, based on the film formation conditions shown in [Table 1] above, silane (SiH ₄ ) gas is supplied at 15 ml / min (standard state) and silicon fluoride (SiF ₄ ) gas is supplied at 15 ml from the gas inlet 31a. / Min (standard state), ammonia (NH ₃ ) gas is set to 3700 ml / min (standard state), and nitrogen (N ₂ ) gas is set to 3000 ml / min (standard state). Further, the pressure in the chamber 31 is set to 36.5 kPa, the above-described source gases are introduced into the chamber 13 to react with each other, and a film thickness of 20 nm is formed on the first interlayer insulating film of the semiconductor substrate 11. A first hydrogen barrier film made of fluorine-containing silicon nitride is formed. Thereafter, the semiconductor substrate 11 on which the first hydrogen barrier film is formed is taken out of the chamber 31 to complete the formation of the first hydrogen barrier film.

Note that the deposition conditions for the first hydrogen barrier film 15 made of fluorine-containing silicon nitride according to the present embodiment shown in [Table 1] are merely examples, and if the design of the semiconductor memory device itself is changed, The film forming conditions can also change significantly. In short, the growth temperature and the gas containing silicon (for example, SiF ₄₎ are set so that the fluorine bond amount in the silicon nitride film does not decrease the amount of polarization of the ferroelectric material, for example, greater than 7 × 10 ²¹ pieces / cm ^3. ) Flow rate and growth pressure conditions are determined, and the first hydrogen barrier film may be formed under the determined conditions.

FIG. 5 shows the amount of fluorine bonds (total number of Si—F and N—F) (number / cm ³ ) in the first hydrogen barrier film 15 made of fluorine-containing silicon nitride and silane (SiF ₄ ) which is one of the source gases. ) Shows the relationship with the gas flow rate (ml / min (standard state)). From FIG. 5, by increasing the flow rate of the SiF ₄ gas, a part of hydrogen bonds (Si—H and N—H) contained in silicon nitride is replaced, and the fluorine content contained in silicon nitride increases. Can be estimated.

Note that the gas containing fluorine used for the chemical vapor reaction is not limited to SiF ₄ , for example, silicon fluoride (SiF ₆ , Si ₂ F ₆ ), sulfur fluoride (SF ₄ ), methyl fluoride (CH _3). F), including fluorine (F) such as arsenic fluoride (AsF ₅ ), phosphorus fluoride (PF ₅ ), boron fluoride (BF ₃ ), fluorocarbon (CF ₄ ), and nitrogen fluoride (NF ₃ ) A film may be formed by combining a gas and an inert gas such as neon (Ne), argon (Ar), krypton (Kr), or xenon (Xe). Further, an organometallic gas containing fluorine may be used as the fluorine source.

  In the present embodiment, the case where the first hydrogen barrier film 15 provided on the lower side of the capacitor 20 having the ferroelectric or high dielectric in the capacitor insulating film 18 is formed of a fluorine-containing silicon nitride film has been described. The hydrogen barrier film made of fluorine-containing silicon nitride is not necessarily limited to the structure provided below the capacitor 20. For example, the same effect can be obtained even if the second hydrogen barrier film 21 provided above and on the side of the capacitor 20 is formed of a fluorine-containing silicon nitride film. Furthermore, the entire periphery of the capacitor 20, that is, the upper side, the side, and the lower side may be covered with a hydrogen barrier film made of fluorine-containing silicon nitride. Also in this case, the hydrogen barrier film made of fluorine-containing silicon nitride may cover one capacitor 20 or may cover a block unit including a plurality of capacitors 20.

  Note that the memory cell structure in the semiconductor memory device may be a planar type or a three-dimensional type.

  In the present embodiment, the configuration using a fluorine-containing silicon nitride film in which hydrogen atoms remaining in the hydrogen barrier film are replaced with fluorine atoms has been described as a hydrogen barrier film. Instead of (SiN), for example, a film containing fluorine and having a hydrogen barrier property, such as fluorine-containing titanium aluminum nitride (TiAlNF), in particular, a hydrogen group is substituted with a fluorine group, and fluorine is contained and hydrogen barrier property. The same effect can be obtained if the film has a thickness.

  In the semiconductor memory device and the manufacturing method thereof according to the present invention, the reduction of the capacity insulating film due to desorbed hydrogen from the hydrogen barrier film can be remarkably reduced, and the deterioration of the capacity insulating film due to hydrogen can be surely prevented. The present invention is useful as a semiconductor memory device having a capacitor using a ferroelectric or high-dielectric material as a film, and a method for manufacturing the same.

11 Semiconductor substrate 12 MOS transistor 12a First impurity diffusion layer 12b Second impurity diffusion layer 13 Bit line 14 First interlayer insulating film 15 First hydrogen barrier film (fluorine-containing silicon nitride film)
16 Contact plug 17 Lower electrode 18 Capacitor insulating film 19 Upper electrode 20 Capacitor 21 Second hydrogen barrier film 22 Second interlayer insulating film 31 Chamber 31a Gas inlet 31b Gas exhaust 32 Susceptor 33 Heating lamp

Claims (11)

A capacitor having a capacitive insulating film made of a ferroelectric or high dielectric formed on a semiconductor substrate;
A hydrogen barrier film formed around the capacitor,
At least a part of the hydrogen barrier film contains fluorine.   2. The semiconductor memory device according to claim 1, wherein in the hydrogen barrier film, a hydrogen group is substituted with a fluorine group.   The semiconductor memory device according to claim 1, wherein the hydrogen barrier film is a fluorine-containing silicon nitride film. 4. The semiconductor memory device according to claim 3, wherein a fluorine bonding amount in the fluorine-containing silicon nitride film is larger than 7 × 10 ²¹ pieces / cm ³ .   5. The semiconductor memory device according to claim 3, wherein the fluorine-containing silicon nitride film has a thickness of 10 nm or more. A plurality of the capacitors are formed on the semiconductor substrate,
The semiconductor memory device according to claim 1, wherein the hydrogen barrier film covers the periphery of each of the plurality of capacitors. A plurality of the capacitors are formed on the semiconductor substrate,
The semiconductor memory device according to claim 1, wherein the hydrogen barrier film covers the periphery of each of two or more capacitors of the plurality of capacitors. Forming a capacitor made of a ferroelectric or a high dielectric on a semiconductor substrate;
Forming a hydrogen barrier film around the capacitor,
In the step of forming the hydrogen barrier film, a first source gas having a bond of silicon and hydrogen, a second source gas having a bond of nitrogen and hydrogen, and fluorine are formed on at least a part of the hydrogen barrier film. A method for manufacturing a semiconductor memory device, comprising: forming a fluorine-containing silicon nitride film by reacting a third source gas including the gas.   In the step of forming the hydrogen barrier film, in the fluorine-containing silicon nitride film, a bond between silicon and hydrogen and a bond between nitrogen and hydrogen are replaced with a bond between silicon and fluorine and a bond between nitrogen and fluorine, respectively. The method of manufacturing a semiconductor memory device according to claim 8, wherein the method is formed.   In the step of forming the hydrogen barrier film, the third source gas includes silicon fluoride, sulfur fluoride, methyl fluoride, arsenic fluoride, phosphorus fluoride, boron fluoride, carbon fluoride, and nitrogen fluoride. 10. The method of manufacturing a semiconductor memory device according to claim 8, wherein at least one gas selected from among the above is used. 11. The method of manufacturing a semiconductor memory device according to claim 8, wherein a fluorine bonding amount in the fluorine-containing silicon nitride film is larger than 7 × 10 ²¹ pieces / cm ³ .

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