JP2004186403A - Method for forming boron nitride film and film forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a boron nitride film with a low specific dielectric constant and an excellent metal spread preventing function. <P>SOLUTION: A high frequency antenna 7 and a high frequency power supply 9 apply plasma processing to ammonium gas 11 mainly introduced to a film forming chamber 2 to generate plasma 10 in the film forming chamber 2, and to react diborane gas introduced to the film forming chamber 2 with the plasma-processed ammonium gas, and controlling the temperature of the board 6 forms the boron nitride film 15 having a low specific dielectric constant and an excellent metal spread preventing function onto the board 6. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for forming a boron nitride film.
[0002]
[Prior art]
In recent years, loss due to capacitance between wirings has become a problem due to high integration of transistors and high-speed switching operation. Further, the material of the wiring applied to the circuit has been changed from an aluminum alloy to a copper material, and the resistance of the wiring has been reduced. As a result, thin film members that come into contact with the wiring are required to have not only a low dielectric constant but also a copper diffusion preventing function.
[0003]
Under such circumstances, attention has been paid to boron nitride (BN) having an extremely low relative permittivity (relative permittivity κ is 4.0 or less). The thin film of boron nitride can be formed by a plasma CVD (Chemical Vapor Deposition) method. However, although a boron nitride film that can be formed so far has a low relative dielectric constant, there is a problem that its function of preventing metal diffusion is not sufficient (for example, see Patent Documents 1 and 2 below).
[0004]
[Patent Document 1]
JP 2002-293516 A [Patent Document 2]
JP-A-2002-016135 [0005]
[Problems to be solved by the invention]
For this reason, at present, there is an urgent need for a film forming method and a film forming apparatus capable of forming a boron nitride film having a certain low dielectric constant and a sufficient metal diffusion preventing function. .
[0006]
The present invention has been made in view of the above circumstances, and provides a film forming method and a film forming apparatus capable of forming a boron nitride film, which can be further applied as a barrier film having a metal diffusion preventing function. The purpose is to provide.
[0007]
[Means for Solving the Problems]
According to a first aspect of the invention, there is provided a film forming method comprising:
A plasma is generated in a film formation chamber, and a diborane gas and an ammonia gas are reacted in the film formation chamber to form a boron nitride film on a substrate.
[0008]
According to a second aspect of the invention, there is provided a film forming method comprising:
In the film forming method according to the first invention,
In the film forming chamber, the diborane gas is reacted with the ammonia gas that has been turned into plasma.
[0009]
According to a third aspect of the invention, there is provided a film forming method comprising:
In the film forming method according to the first or second invention,
Diborane / ammonia, which is a ratio of a flow rate at which the diborane gas is supplied into the film formation chamber and a flow rate at which the ammonia gas is supplied into the film formation chamber, is set to 0.1 to 1.
[0010]
According to a fourth aspect of the present invention, there is provided a film forming method comprising:
In the film forming method according to the third invention,
The pressure at the time of film formation in the film formation chamber is set to 0.5 mTorr to 10 mTorr, and the total gas flow rate of the diborane gas flow rate and the ammonia gas flow rate is set to 100 sccm to 1000 sccm.
[0011]
According to a fifth aspect of the present invention, there is provided a film forming method comprising:
In the film forming method according to any one of the first to fourth inventions,
The temperature of the substrate may be set in a range of 200 ° C. to 450 ° C.
[0012]
According to a sixth aspect of the invention, there is provided a film forming method comprising:
In the film forming method according to any one of the first to fifth inventions,
The diborane gas is diluted with a gas other than diborane gas.
[0013]
According to a seventh aspect of the invention, there is provided a film forming method comprising:
In the film forming method according to any one of the first to sixth inventions,
The boron nitride film is a barrier film for preventing metal diffusion.
[0014]
According to an eighth aspect of the present invention, there is provided a film forming apparatus comprising:
A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit for introducing diborane gas, inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
The method is characterized in that a boron nitride film is formed on a substrate.
[0015]
According to a ninth aspect of the invention, there is provided a film forming apparatus,
A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit that introduces diborane gas inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
Pressure control means for controlling the internal pressure of the film forming chamber,
Gas flow rate control means for controlling the flow rates of the ammonia gas and the diborane gas,
Temperature control means for controlling the temperature of the substrate holding unit,
The method is characterized in that a boron nitride film is formed on a substrate.
[0016]
According to a tenth aspect of the invention, there is provided a film forming apparatus comprising:
In a film forming apparatus according to a ninth aspect,
The gas flow rate control means sets diborane / ammonia, which is a ratio of the flow rate of the diborane gas to the flow rate of the ammonia gas, to 0.1 to 1.
[0017]
A film forming apparatus according to an eleventh invention for solving the above object,
In a film forming apparatus according to a ninth aspect,
The pressure control unit sets a pressure at the time of film formation in the film formation chamber to 0.5 mTorr to 10 mTorr,
The gas flow rate control means sets diborane / ammonia, which is the ratio of the flow rate of the diborane gas to the flow rate of the ammonia gas, to 0.1 to 1 and the total gas flow rate of the diborane gas and the flow rate of the ammonia gas. The flow rate is set to 100 sccm to 1000 sccm.
[0018]
A film forming apparatus according to a twelfth invention for solving the above-mentioned object,
In the film forming apparatus according to any one of the ninth to eleventh aspects,
The temperature of the substrate is set at 200 ° C. to 450 ° C. by the temperature control means.
[0019]
A film forming apparatus according to a thirteenth invention that solves the above object,
In the film forming apparatus according to any one of the eighth to twelfth aspects,
The diborane gas is diluted with a gas other than diborane gas.
[0020]
A film forming apparatus according to a fourteenth invention for solving the above object,
In the film forming apparatus according to any one of the eighth to thirteenth aspects,
The boron nitride film is a barrier film for preventing metal diffusion.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
<About boron nitride film formation>
A film forming method and a film forming apparatus according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a schematic perspective sectional view of a film forming apparatus for performing a film forming method according to an embodiment of the present invention.
[0022]
As shown in FIG. 1, a film forming chamber 2 is formed in a cylindrical container 1, and a circular ceiling plate 3 is provided above the container 1. An electrostatic chuck 4 as a substrate holding unit is provided in a film forming chamber 2 at the center of the container 1, and a DC power supply 5 for an electrostatic chuck is connected to the electrostatic chuck 4 so that a semiconductor substrate 6 is Is electrostatically adsorbed and held on the upper surface of the substrate.
[0023]
A high frequency antenna 7 having, for example, a circular ring shape is arranged on the ceiling plate 3, and a high frequency power supply 9 is connected to the high frequency antenna 7 via a matching unit 8. By supplying power to the high-frequency antenna 7, an electromagnetic wave enters the film forming chamber 2 of the container 1. The electromagnetic wave incident on the film forming chamber 2 ionizes the gas introduced into the film forming chamber 2 to generate plasma 10 (plasma generating means).
[0024]
The container 1 includes an ammonia gas nozzle 12 serving as an ammonia gas introduction unit for introducing an ammonia gas (NH ₃ gas) 11 (> 99.999%) into the film formation chamber 2, and a film formation chamber below the ammonia gas nozzle 12. 2 is provided with a diborane gas nozzle 14 as a diborane gas introduction means for introducing a diborane (B ₂ H ₆ ) -containing gas 13. The diborane-containing gas 13 introduced from the diborane gas nozzle 14 into the film forming chamber 2 is a diborane gas diluted with hydrogen (H ₂ ) gas (diborane gas concentration: 1% to 5%). As a gas for diluting diborane gas, an inert gas such as helium, neon, argon, krypton, xenon, or the like can be used in addition to hydrogen gas.
[0025]
In the plasma CVD apparatus described above, the substrate 6 is placed on the electrostatic chuck 4 and is electrostatically attracted. The inside of the film formation chamber 2 is adjusted to a predetermined pressure by a vacuum pump (not shown) or the like as a pressure control means, and an ammonia gas 11 is introduced at a predetermined flow rate from an ammonia gas nozzle 12, and a diborane-containing gas 13 is supplied from a diborane gas nozzle 14. Is introduced at a predetermined flow rate. By applying high-frequency power (1 MHz to 100 MHz, 1 kW to 10 kW) from the high-frequency power supply 9 to the high-frequency antenna 7 via the matching unit 8, the ammonia gas 11 is mainly excited in the film forming chamber 2 to be in a plasma state, After the ammonia gas 11 is excited, the ammonia gas 11 is mixed and reacted with the diborane-containing gas 13 to form a boron nitride (BN) film 15 on the substrate 6. At this time, the temperature of the substrate 6 is set from 200 ° C. to 450 ° C. by a heater (not shown) as a temperature control means.
[0026]
In the film forming chamber 2, since the ammonia gas nozzle 12 is provided on the high frequency antenna 7 side, the ammonia gas 11 is mainly excited and turned into plasma, and the ammonia gas converted into plasma and the diborane gas diluted with hydrogen gas react with each other. I do. By this reaction, gaseous boron nitride and hydrogen gas are generated, the hydrogen gas is exhausted, and a boron nitride film 15 is formed on the substrate 6. When the ammonia gas nozzle 12 and the diborane gas nozzle 14 are arranged in reverse, that is, when the diborane gas nozzle 14 is arranged on the high-frequency antenna 7 side to convert the diborane-containing gas 13 into plasma, boron is solidified and does not react with the ammonia gas.
[0027]
As for the flow rate of the ammonia gas 11 from the ammonia gas nozzle 12 and the flow rate of the diborane-containing gas 13 from the diborane gas nozzle 14, the diborane / ammonia flow rate ratio, which is the ratio of the flow rate of the ammonia gas to the flow rate of the diborane gas, is 0.1 to 1. It is set as follows. Preferably, the flow rate ratio is set to be 0.2 to 0.5. More preferably, the flow rate is set so as to be 0.25.
[0028]
The pressure during film formation in the film forming chamber 2 is set to 0.5 mTorr to 10 mTorr. Preferably, it is 1 mTorr to 5 mTorr. More preferably, it is 2 mTorr to 3 mTorr. Further, the total gas flow rate of the diborane gas flow rate and the ammonia gas flow rate is set to 100 sccm to 1000 sccm. Preferably, it is 100 sccm to 400 sccm. More preferably, it is 200 sccm to 300 sccm.
[0029]
<About physical properties of boron nitride film>
When the voltage-current measurement was performed on the boron nitride film 15 formed according to the above-described embodiment under the measurement conditions of room temperature and 2 MV / cm, the leakage current characteristics of the boron nitride film were equivalent to that of the silicon oxide film (SiO ₂ film). Was confirmed.
[0030]
Next, a barrier property evaluation test was performed on the boron nitride film 15 formed according to the present embodiment. The barrier property is a function of a thin film that prevents a metal (for example, copper, silver, or the like) in contact with the thin film from diffusing into the thin film at an atomic level. FIG. 2 is a diagram conceptually showing a method for evaluating and testing barrier properties. First, the Cu electrode 22 was formed on the surface of the barrier film 21 to be evaluated, and the interlayer insulating film 23 and the Al electrode 24 were formed on the back surface of the barrier film 21, thereby manufacturing the capacitor 20. With respect to this capacitor 20, the insulation property of the barrier film 21 was evaluated by voltage-current characteristics. Next, in order to perform an acceleration test, the capacitor 20 was heated at 200 ° C. for 10 minutes. With respect to the capacitor 20 after the acceleration test, the insulation property of the barrier film 21 was evaluated by voltage-current characteristics.
[0031]
The insulation evaluation values before and after the acceleration test (heat treatment) were compared to evaluate the barrier properties. That is, when the insulation (value) before the acceleration test was set to 100% of the barrier property, the barrier property was evaluated based on how much the insulation (value) after the acceleration test was reduced.
[0032]
Further, as for the boron nitride film 15 for which the barrier property was evaluated, a film formed by changing various film forming conditions was evaluated. The film forming conditions were changed by independently changing the diborane / ammonia flow rate ratio, the total gas flow rate of diborane gas and ammonia gas, and the internal pressure of the film forming chamber 2.
[0033]
FIG. 3 is a diagram showing the results of evaluating the barrier properties of the boron nitride film 15 formed by changing the flow rate ratio of diborane / ammonia. As shown in the figure, when the diborane / ammonia flow rate ratio is 0.1 to 1, a boron nitride film having high barrier properties can be formed. On the other hand, when the diborane / ammonia flow rate ratio is 0.05, the nitrogen content in the boron nitride film is large, and when the diborane / ammonia flow rate ratio is 1.1, the boron content in the boron nitride film is high. Since the content is large, the barrier property is reduced.
[0034]
FIG. 4 is a diagram showing the results of evaluating the barrier properties of the boron nitride film 15 formed by changing the total gas flow rate of diborane gas and ammonia gas. As shown in the figure, when the total gas flow rate of the diborane gas and the ammonia gas is 100 sccm to 1000 sccm, it can be seen that a boron nitride film having a high barrier property can be formed. On the other hand, when the total gas flow rate of diborane gas and ammonia gas is 50 sccm, the gas is diluted. When the total gas flow rate of diborane gas and ammonia gas is 1100 sccm, the gas is rich. The film cannot be formed well, and the barrier property is reduced.
[0035]
FIG. 5 is a diagram showing the evaluation results of the barrier properties of the boron nitride film 15 formed by changing the internal pressure of the film forming chamber 2. As shown in the figure, it can be seen that when the internal pressure of the film forming chamber 2 is 0.5 mTorr to 10 mTorr, a boron nitride film having high barrier properties can be formed. On the other hand, when the internal pressure of the film forming chamber 2 is 0.3 mTorr, the gas is diluted, and when the internal pressure of the film forming chamber 2 is 11 mTorr, the gas is dense, so that the boron nitride film is formed. But the barrier properties are reduced.
[0036]
In the film forming method using the plasma CVD apparatus according to the present embodiment, the nitride having excellent mechanical and chemical resistance, high thermal conductivity, low relative dielectric constant, and excellent insulating properties due to high barrier properties is provided. The boron film 15 can be formed. Further, by using diborane gas as the boron source, it is possible to increase the deposition rate.
[0037]
<Application of boron nitride film as barrier film>
FIG. 6 is a schematic configuration diagram of an integrated circuit using a boron nitride film formed by the plasma CVD apparatus according to the present embodiment as a barrier film. An example in which the boron nitride film according to the present embodiment is applied as a barrier film will be described with reference to FIG.
[0038]
As shown in FIG. 1, in a highly integrated circuit (LSI), loss due to capacitance between the wirings 32 is eliminated in order to achieve high integration of the transistor 31 and high-speed switching operation. For this reason, in the manufacturing process, a film having a low dielectric constant is used as the interlayer insulating film 33 and the barrier film 35 existing between the wirings 32.
[0039]
As the interlayer insulating film 33, an organic coating film or a porous film having a low dielectric constant has been generally employed. However, even if the interlayer insulating film 33 such as an organic coating film has a low relative dielectric constant, there is a problem in terms of mechanical / chemical resistance and thermal conductivity. For this reason, in recent years, as described in the section of the prior art, a boron nitride thin film that realizes an extremely low relative dielectric constant and solves problems such as mechanical characteristics (see JP-A-2002-293516, ) Is used.
[0040]
In addition, even if a low specific dielectric constant boron nitride film formed by the above-described known film forming technique is applied as the interlayer insulating film 33, the relative dielectric constant of the barrier film 35, which is another member existing between the wirings 32, may be increased. If the rate is not low, an increase in the capacity between the wirings 32 causes a problem. However, although the conventional boron nitride film has a low relative dielectric constant, it has a low barrier property and cannot be used as a barrier film. Therefore, as the barrier film 35, the boron nitride film according to the present embodiment which is excellent in barrier properties while substantially maintaining a low dielectric constant is applied. The boron nitride film according to the present embodiment achieves an excellent barrier property while maintaining a low relative dielectric constant substantially equal to the conventional one by the above-described specific film forming method and film forming apparatus. This is applicable as the film 35.
[0041]
In addition, as a result of performing voltage-capacity measurement on the organic insulating film or the porous interlayer insulating film 33 and the protective film 34, it was confirmed that the relative dielectric constant κ was κ <2.2.
[0042]
FIG. 7 shows an example in which the boron nitride film according to the present embodiment is applied not only to the barrier film 35 around the wiring 32 but also to the protective film 36 between the interlayer insulating films 33. The boron nitride film according to this embodiment can also be applied as the protective film 36 between the interlayer insulating films 33. This makes it possible to meet the requirements of the interlayer insulating film 33 suitable for an LSI process in which processing conditions are strict while maintaining adhesion and moisture absorption resistance.
[0043]
【The invention's effect】
According to the film forming method of the first invention,
Plasma is generated in the film formation chamber, a diborane gas and an ammonia gas are reacted in the film formation chamber, and a boron nitride film is formed on the substrate. A boron nitride film having a high, low dielectric constant and excellent barrier properties can be formed at a high speed. That is, by forming a barrier film, a protective film, and the like made of a boron nitride film having a relative dielectric constant of about 4 or less in a wiring forming process of an integrated circuit, the capacitance between wirings in the same layer and the capacitance between wirings that cause wiring delay are increased. It is possible to manufacture a device that achieves high speed by a simple method, and furthermore, has a low dielectric constant while securing a function of preventing diffusion of a metal contained in the boron nitride film. Can be effectively utilized.
[0044]
According to the film forming method according to the second invention,
In the film forming method according to the first invention,
Since the diborane gas is reacted with the ammonia gas that has been turned into plasma in the film forming chamber, solid deposition of boron during film formation can be prevented in addition to the effect according to the first aspect.
[0045]
According to the film forming method of the third invention,
In the film forming method according to the first or second invention,
Since diborane / ammonia, which is the ratio between the flow rate of supplying the diborane gas into the film formation chamber and the flow rate of supplying the ammonia gas into the film formation chamber, is set to 0.1 to 1, more effective. A boron nitride film having a low dielectric constant and a high barrier property can be formed.
[0046]
According to the film forming method of the fourth invention,
In the film forming method according to the third invention,
The pressure at the time of film formation in the film formation chamber is set to 0.5 mTorr to 10 mTorr, and the total gas flow rate of the flow rate of the diborane gas and the flow rate of the ammonia gas is set to 100 sccm to 1000 sccm. A boron nitride film having a low dielectric constant and a high barrier property can be formed.
[0047]
According to the film forming method of the fifth invention,
In the film forming method according to any one of the first to fourth inventions,
Since the temperature of the substrate is set at 200 ° C. to 450 ° C., a boron nitride film having a low dielectric constant and a high barrier property can be formed more effectively.
[0048]
According to the film forming method of the sixth aspect,
In the film forming method according to any one of the first to fifth inventions,
Since the diborane gas is diluted with a gas other than the diborane gas, a boron nitride film having a low dielectric constant and a high barrier property can be formed more effectively.
[0049]
According to the film forming method of the seventh invention,
In the film forming method according to any one of the first to sixth inventions,
Since the boron nitride film is a barrier film for preventing metal diffusion, it has excellent mechanical and chemical resistance, high thermal conductivity, low relative dielectric constant, and excellent barrier properties. A film can be formed.
[0050]
According to the film forming apparatus of the eighth aspect,
A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit for introducing diborane gas, inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
Since a boron nitride film is to be formed on the substrate, a boron nitride film with excellent mechanical and chemical resistance, high thermal conductivity, low dielectric constant and excellent barrier properties can be formed at high speed. be able to.
[0051]
According to the film forming apparatus of the ninth aspect,
A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit that introduces diborane gas inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
Pressure control means for controlling the internal pressure of the film forming chamber,
Gas flow rate control means for controlling the flow rates of the ammonia gas and the diborane gas,
Temperature control means for controlling the temperature of the substrate holding unit,
Since a boron nitride film is to be formed on the substrate, a boron nitride film with excellent mechanical and chemical resistance, high thermal conductivity, low dielectric constant and excellent barrier properties can be formed at high speed. be able to.
[0052]
According to the film forming apparatus of the tenth aspect,
In a film forming apparatus according to a ninth aspect,
The gas flow rate control means sets diborane / ammonia, which is the ratio of the flow rate of the diborane gas to the flow rate of the ammonia gas, to 0.1 to 1, so that the low dielectric constant and high dielectric constant can be more effectively achieved. A boron nitride film having a barrier property can be formed.
[0053]
According to the film forming apparatus of the eleventh aspect,
In a film forming apparatus according to a ninth aspect,
The pressure control unit sets a pressure at the time of film formation in the film formation chamber to 0.5 mTorr to 10 mTorr,
The gas flow rate control means sets diborane / ammonia, which is the ratio of the flow rate of the diborane gas to the flow rate of the ammonia gas, to 0.1 to 1 and the total gas flow rate of the diborane gas and the flow rate of the ammonia gas. Since the flow rate is set to 100 sccm to 1000 sccm, a boron nitride film having a low dielectric constant and a high barrier property can be more effectively formed.
[0054]
According to the film forming apparatus of the twelfth aspect,
In the film forming apparatus according to any one of the ninth to eleventh aspects,
Since the temperature of the substrate is set at 200 ° C. to 450 ° C. by the temperature control means, a boron nitride film having a low dielectric constant and a high barrier property can be formed more effectively.
[0055]
According to the film forming apparatus of the thirteenth aspect,
In the film forming apparatus according to any one of the eighth to twelfth aspects,
Since the diborane gas is diluted with a gas other than the diborane gas, a boron nitride film having a low dielectric constant and a high barrier property can be formed more effectively.
[0056]
According to the film forming apparatus of the fourteenth aspect,
In the film forming apparatus according to any one of the eighth to thirteenth aspects,
Since the boron nitride film is a barrier film for preventing metal diffusion, it has excellent mechanical and chemical resistance, high thermal conductivity, low relative dielectric constant, and excellent barrier properties. A film can be formed.
[Brief description of the drawings]
FIG. 1 is a schematic perspective sectional view of a film forming apparatus for performing a film forming method according to an embodiment of the present invention.
FIG. 2 is a diagram conceptually showing an evaluation test method for barrier properties.
FIG. 3 is a view showing the results of evaluating the barrier properties of a boron nitride film formed by changing the flow rate ratio of diborane / ammonia.
FIG. 4 is a diagram showing the results of evaluating the barrier properties of a boron nitride film formed by changing the total gas flow rate of diborane gas and ammonia gas.
FIG. 5 is a diagram showing the results of evaluating the barrier properties of a boron nitride film formed by changing the internal pressure of a film forming chamber.
FIG. 6 is a schematic configuration diagram of an integrated circuit using a boron nitride film formed by a plasma CVD apparatus according to the present embodiment as a barrier film.
FIG. 7 is a schematic configuration diagram of an integrated circuit in which the boron nitride film according to the embodiment is applied to a barrier film and a protective film.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Container 2 Deposition chamber 3 Ceiling plate 4 Electrostatic chuck 5 DC power supply for electrostatic chuck 6 Substrate 7 High frequency antenna 8 Matching device 9 High frequency power supply 10 Plasma 11 Ammonia gas 12 Ammonia gas nozzle 13 Diborane-containing gas (B ₂ H _6- containing gas) )
14 Diborane gas nozzle 15 Boron nitride film 20 Capacitor 21 Barrier film 22 Cu electrode 23 Interlayer insulating film 24 Al electrode 31 Transistor 32 Wiring 33 Interlayer insulating film 34 Protective film 35 Barrier film 36 Protective film (the boron nitride film of the present invention is applied)

Claims (14)

A film formation method, comprising: generating plasma in a film formation chamber; and reacting diborane gas and ammonia gas in the film formation chamber to form a boron nitride film on a substrate. The film forming method according to claim 1,
A film forming method, wherein the diborane gas is reacted with ammonia gas which has been turned into plasma in the film forming chamber. 3. The film forming method according to claim 1, wherein
A film forming method, wherein diborane / ammonia, which is a ratio of a flow rate of supplying the diborane gas into the film forming chamber and a flow rate of supplying the ammonia gas into the film forming chamber, is set to 0.1 to 1. . The film forming method according to claim 3,
A film forming method, wherein a pressure at the time of film formation in the film forming chamber is set to 0.5 mTorr to 10 mTorr, and a total gas flow rate of the diborane gas flow rate and the ammonia gas flow rate is set to 100 sccm to 1000 sccm. 5. The film forming method according to claim 1, wherein the temperature of the substrate is set at 200.degree. C. to 450.degree. 6. The film forming method according to claim 1, wherein said diborane gas is diluted with a gas other than diborane gas. 7. The film forming method according to claim 1, wherein said boron nitride film is a barrier film for preventing metal diffusion. A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit that introduces diborane gas inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
A film forming apparatus for forming a boron nitride film on a substrate. A plasma generating means installed at an upper part of the film forming chamber and generating plasma inside the film forming chamber;
A substrate holding unit installed at a lower part of the film forming chamber,
Ammonia gas introduction means for introducing ammonia gas inside the film forming chamber and toward the plasma generation means,
A diborane gas introduction unit for introducing a diborane gas inside the film forming chamber and below a location of the ammonia gas introduced by the ammonia gas introduction unit,
Pressure control means for controlling the internal pressure of the film forming chamber,
Gas flow rate control means for controlling the flow rates of the ammonia gas and the diborane gas,
Temperature control means for controlling the temperature of the substrate holding unit,
A film forming apparatus for forming a boron nitride film on a substrate. The film forming apparatus according to claim 9,
A film forming apparatus, wherein the gas flow rate control means sets diborane / ammonia, which is a ratio between the flow rate of the diborane gas and the flow rate of the ammonia gas, to 0.1 to 1. The film forming apparatus according to claim 9,
The pressure control unit sets a pressure at the time of film formation in the film formation chamber to 0.5 mTorr to 10 mTorr,
The gas flow rate control means sets diborane / ammonia, which is the ratio of the flow rate of the diborane gas to the flow rate of the ammonia gas, to 0.1 to 1, and the total gas flow rate of the diborane gas and the flow rate of the ammonia gas. A film forming apparatus, wherein the flow rate is set to 100 sccm to 1000 sccm. The film forming apparatus according to any one of claims 9 to 11, wherein the temperature of the substrate is set to 200 ° C to 450 ° C by the temperature control means. The film forming apparatus according to any one of claims 8 to 12,
The film forming apparatus, wherein the diborane gas is diluted with a gas other than the diborane gas. The film forming apparatus according to any one of claims 8 to 13,
The film forming apparatus, wherein the boron nitride film is a barrier film for preventing metal diffusion.

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