JP2006161071A - Apparatus and method for producing nitrided metal film, and nitrided metal film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nitrided metal film; a production apparatus for the nitrided metal film; and a production method therefor. <P>SOLUTION: The method for forming the nitrided metal film 18 on a substrate 3 includes nitriding a tantalum component with nitrogen gas plasma obtained by converting nitrogen gas into plasma, when producing a precursor 17 of tantalum chloride gas by etching a member 14 made from tantalum to be etched in a chamber 1 which accommodates a substrate 3 mounted on a susceptor 2, with chlorine gas plasma 16 diluted with helium, by cooling the substrate 3 into a lower temperature than that of the member 14 and making the substrate 3 adsorb the precursor 17, and by reducing the adsorbed precursor 17 with the chlorine gas plasma to convert a tantalum component into a film on the substrate 3, wherein an atomic composition ratio N/M of nitrogen atoms to metallic atoms in the nitrided metal film 18 is controlled to a value larger than 0 but 1 or smaller, by controlling an amount of supplied nitrogen gas and controlling a flow ratio of nitrogen gas/halogen gas to a value more than 0 but 0.1 or less. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal nitride film manufacturing apparatus, a manufacturing method, and a metal nitride film for manufacturing a metal nitride film. It can be used as a surface treatment film of a chemical container that requires decoration and corrosion resistance.

  In recent years, metal nitride films have been used in various fields, for example, as gate electrode films of transistors and as barrier metal films for the purpose of preventing copper diffusion in copper wirings such as LSIs.

  When used in these applications, it is necessary to use a metal nitride film in which various film characteristics such as work function are controlled. For example, the atomic composition ratio of nitrogen atoms to metal atoms in the metal nitride film can be used as a characteristic control technique. A method for controlling a certain N / M ratio can be mentioned.

  Furthermore, factors affecting the characteristics of the metal nitride film include the film formation temperature and the amount of impurities contained in the film. In particular, metal nitride films used for semiconductors are sensitive to these factors, and the film deposition temperature is lowered to suppress damage to the film formation substrate and the film itself, and the amount of impurities is reduced to reduce film reliability. In addition, it is necessary to improve the controllability of film characteristics.

  Conventionally, methods for forming a metal nitride film include a chemical vapor deposition method (CVD method: see Patent Document 1 below) and a reactive sputtering method. In the CVD method, an organic metal gas and a reducing gas contain nitrogen gas, and these gases are converted into plasma, for example, and excited to react, so that nitrogen atoms are contained in the metal film to be formed. Is the method. The reactive sputtering method is a method in which a metal target is sputtered with a sputtering gas containing nitrogen gas and nitrogen atoms are contained in the metal film to be formed.

  However, since the CVD method uses an organic metal gas or the like for film formation, a carbon component, a hydrogen component, or the like in the organic metal gas is contained as an impurity in the metal nitride film, and the film quality may be deteriorated. Usually, in the CVD method in which film formation is performed at a high temperature, the amount of impurities remaining in the metal nitride film when the film is formed at a relatively low temperature in order to reduce damage to the film formation substrate and the film itself due to the film formation temperature. There is a particular problem that the amount of impurities increases and this impurity may be mixed.

  Further, in the CVD method, film formation is performed at a high temperature, and the film formation reaction proceeds in a thermal equilibrium state. As a result, a metal nitride that is a stoichiometrically stable material, for example, tantalum nitride has a 1: 1 ratio of nitrogen and tantalum. Film formation becomes dominant, and there is a problem that it is extremely difficult to control the N / M ratio (for example, to control the N / M ratio to 1 or less) only by controlling the amount of nitrogen gas supplied.

  In the reactive sputtering method, the substrate on which the metal nitride film is formed is electrically damaged due to the film formation principle, and as pointed out also in Patent Document 1 below, step coverage Therefore, there is a problem that uniform film formation in a complicated shape is difficult.

  In addition, since the physical film forming principle called sputtering is used, the nitriding reaction of metals (particularly refractory metals) is extremely insensitive, and the N / M ratio can be freely controlled (for example, the N / M ratio). There is a problem that it is extremely difficult to form a metal nitride film in which the film quality is controlled to 1 or less, and there is a possibility that the reliability of the film quality is lowered because it is not a stable nitriding reaction.

  For these film formation methods, the present inventors etched a member to be etched formed of a metal capable of generating a high vapor pressure halide by halogen gas plasma to generate a precursor made of the metal halide. Have already proposed a method of forming a metal nitride film by nitriding a metal component with nitrogen gas plasma when the metal component is formed by reducing the precursor with halogen gas plasma in the vicinity of the substrate. (See Patent Documents 2 to 7 below.)

  As described in the following Patent Documents 2 to 7, this metal nitride film forming method has a problem of deterioration of film quality due to inclusion of impurities and a problem that it is difficult to uniformly form a complicated shape. This is a solved film formation method, and there is no fear that the film formation substrate or the film itself is electrically damaged from the film formation principle.

Japanese Patent Laid-Open No. 5-47707 JP 2004-197192 A JP 2004-83945 A JP 2004-83946 A JP 2003-213423 A Japanese Patent Laid-Open No. 2003-247071 JP 2004-197196 A JP 2004-200560 A

  However, the film forming methods described in Patent Documents 2 to 7 are examples of forming a metal nitride film mainly used as a barrier metal and examples of forming a metal nitride film as an adhesion preventing film. The N / M ratio of the metal nitride film to be formed was not considered.

  This is because when a metal nitride film is used as a barrier metal, the metal diffusion preventing property, the denseness, the adhesion to the substrate, etc. of the film are the film characteristics required for the metal nitride film. This is because it has been achieved by controlling the pressure in the chamber, controlling the film formation temperature, plasma conditions, hydrodynamics of the gas supplied into the chamber, and examining the laminated form of the metal nitride film and the metal film.

  In addition, when forming a metal nitride film, an example is proposed in which nitrogen gas is not supplied as a nitrogen source but a part of the member to be etched is used as a solid nitride as a nitrogen source (see the above-mentioned patent document). 8).

  In this film forming method, a member to be etched is composed of a metal portion capable of forming a high vapor pressure halide and a solid nitride portion, and the metal portion of the member to be etched is halogenated by etching with a halogen gas plasma. This is a method of forming a metal nitride film by forming a precursor made of metal and etching a solid nitride portion to generate nitrogen radicals so that the nitrogen radicals are involved in film formation.

  However, in this film forming method, since the member to be etched is manufactured from a plurality of parts, there is a problem that it is difficult to manufacture the member to be etched itself, there is a fear that the airtightness in the chamber cannot be maintained, and etching is performed by each part. There is a problem that it is difficult to control the N / M ratio due to the difference in reactivity.

  Further, etching of solid nitride, for example, silicon nitride (SiN) also generates impurities such as silicon, so that there is a problem that impurities are mixed into the metal nitride film, and the portion of the solid nitride in the member to be etched and the metal There is also a problem that the N / M ratio cannot be freely controlled because the component ratio of the portion cannot be freely changed.

  The present invention has been made in view of the above circumstances, and eliminates the possibility of contamination by impurities and damage to the metal nitride film due to film formation at a high temperature, and also has a N / M ratio freely controlled. It is an object of the present invention to provide a metal nitride film in which the / M ratio is controlled to be greater than 0 and 1 or less, and a metal nitride film production apparatus and production method for producing the metal nitride film.

A metal nitride film forming apparatus according to a first invention (corresponding to claim 1) that solves the above-described problem,
A chamber in which the substrate is accommodated, a support base on which the substrate is placed,
A member to be etched formed of a metal capable of generating a high vapor pressure halide and provided at a position facing the substrate;
Halogen gas supply means for supplying halogen gas to the chamber;
Nitrogen gas supply means for supplying nitrogen gas to the chamber;
Plasma generating means for generating halogen gas plasma and nitrogen gas plasma by converting the halogen gas and nitrogen gas into plasma;
Temperature control means for lowering the temperature of the substrate lower than the temperature of the member to be etched,
The member to be etched is etched with the halogen gas plasma to generate a precursor made of a metal halide, and the metal component is nitrided with the nitrogen gas plasma when the metal component of the precursor is formed on the substrate. In the metal nitride film manufacturing apparatus for forming a metal nitride film on the substrate,
Gas supply amount control means for controlling the supply amount of the nitrogen gas is provided so that an N / M ratio, which is an atomic composition ratio between nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value. This is a metal nitride film manufacturing apparatus.

  The ability to form a metal nitride film whose N / M ratio is freely controlled means that, for example, a metal nitride film whose work function is freely controlled can be formed. Therefore, for example, by applying a metal nitride film whose work function is freely controlled to the gate electrode of the transistor, an optimum transistor is manufactured regardless of the transistor structure and transistor characteristics.

The second invention (corresponding to claim 2)
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed with an insulating member,
The plasma generating means comprises a planar coil disposed outside the insulating member and a power supply unit for supplying power to the coil.
The member to be etched is an apparatus for producing a metal nitride film, wherein the member to be etched is disposed between the substrate and the insulating member, and is formed in a shape that allows the precursor to be supplied to the substrate.

  The member to be etched formed in such a shape that the precursor can be supplied to the substrate, for example, extends in the radial direction of the chamber between the substrate and the insulating member and is discontinuous with respect to the flow direction of the current flowing in the planar coil. Examples include a structure composed of a plurality of rod members arranged in the circumferential direction so as to be in a state, and a structure such as a lattice shape or a mesh shape. Moreover, the to-be-etched member which has a slit-shaped notch part (space) may be sufficient.

The third invention (corresponding to claim 3)
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means is a metal nitride film manufacturing apparatus comprising a coil wound around the chamber and a power supply unit for supplying power to the coil.

The fourth invention (corresponding to claim 4)
In the metal nitride film manufacturing apparatus according to the first invention,
The support is grounded;
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes the member to be etched, a power supply unit that supplies power to the member to be etched, and the grounded support base, and generates gas plasma between the member to be etched and the support base. This is a feature of a metal nitride film manufacturing apparatus.

  By using the member to be etched itself as an electrode for plasma generation, a plasma antenna in the upper part of the chamber and around the cylindrical part is not required, and the degree of freedom of configuration around the apparatus is increased.

The fifth invention (corresponding to claim 5)
In the metal nitride film manufacturing apparatus according to the first invention,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas supply means is provided in the upper chamber,
The nitrogen gas supply means is provided in the lower chamber,
The plasma generating means is a metal nitride film manufacturing apparatus provided in each of the upper chamber and the lower chamber.

The sixth invention (corresponding to claim 6)
In the metal nitride film manufacturing apparatus according to the first invention,
An apparatus for producing a metal nitride film, comprising elevating drive means for elevating and lowering the support base inside the chamber.

The seventh invention (corresponding to claim 7)
In the metal nitride film manufacturing apparatus according to the first invention,
The plasma generation means is configured as an external plasma generation means outside the chamber body, and the halogen gas supply means and the nitrogen gas supply means supply the halogen gas and the nitrogen gas to the external plasma generation means. ,
In the metal nitride film manufacturing apparatus, the halogen gas plasma and the nitrogen gas plasma are previously converted into plasma outside the chamber body by the external plasma generating means and supplied to the vicinity of the member to be etched. is there.

The eighth invention (corresponding to claim 8)
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil, and is an external plasma installed outside the chamber body. Configured as a generating means,
The halogen gas supply means supplies halogen gas to the cylindrical passage,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The halogen gas plasma and the nitrogen gas plasma are plasmas that are preliminarily converted into plasma outside the chamber body by the external plasma generating means and are supplied to the vicinity of the member to be etched. It is a manufacturing device.

  By generating gas plasma in the external plasma generation means isolated from the chamber, the risk of the substrate being directly exposed to the plasma is suppressed, and the plasma damage is suppressed. For example, in the case where film formation is further performed on a substrate on which a film of another material has already been formed, the second film formation can be performed without damaging the film of the material already formed.

The ninth invention (corresponding to claim 9)
In the metal nitride film manufacturing apparatus according to any one of the first to eighth inventions,
A second external plasma generation unit provided on a side wall of the chamber at substantially the same height as the substrate; the nitrogen gas supply unit supplies the nitrogen gas to the second external plasma generation unit;
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generating means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber. This is a metal film manufacturing apparatus.

The tenth invention (corresponding to claim 10)
In the metal nitride film manufacturing apparatus according to any one of the first to eighth inventions,
A first passage is provided on a side wall of the chamber at substantially the same height as the substrate, and includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil. Two external plasma generating means,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generating means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber. This is a metal film manufacturing apparatus.

  By supplying nitrogen gas as nitrogen gas plasma to the upper surface of the substrate from an external plasma generating means installed at almost the same height as the substrate, there is no risk of passivation of the member to be etched by nitrogen radicals. Thereby, a metal nitride film in which the N / M ratio is controlled with higher accuracy is formed.

  Further, it is considered that the generation rate of the nitriding reaction in the vicinity of the substrate is increased by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate. Therefore, it is advantageous when it is desired to efficiently form a metal nitride film having a relatively high N / M ratio.

The eleventh invention (corresponding to claim 11) is
In the metal nitride film manufacturing apparatus according to any one of the first to tenth inventions,
The N / M ratio is a metal nitride film forming apparatus characterized in that the N / M ratio is greater than 0 and 1 or less.

The twelfth invention (corresponding to claim 12)
In the metal nitride film manufacturing apparatus according to any one of the first to eleventh inventions,
The supply amount of nitrogen gas controlled by the gas supply amount control means is such that a nitrogen gas / halogen gas flow rate ratio, which is a ratio to the supply amount of the halogen gas, is greater than 0 and less than or equal to 0.1. This is a metal nitride film manufacturing apparatus.

  The flow rate ratio of nitrogen gas / halogen gas may be controlled in the range of greater than 0 to 0.05 or less and greater than 0 to 0.03 or less. By controlling the flow rate ratio of nitrogen gas / halogen gas to 0.1 or less, 0.05 or less, or 0.03 or less, a metal nitride film in which the N / M ratio is freely controlled to be greater than 0 and 1 or less is formed. In particular, by controlling the nitrogen gas / halogen gas flow rate ratio within the range of 0.005 or more and 0.025 or less, the linear correspondence relationship between the nitrogen gas / halogen gas flow rate ratio and the N / M ratio can be utilized. Film formation is performed with high accuracy of the ratio.

The thirteenth invention (corresponding to claim 13)
In the metal nitride film manufacturing apparatus according to any one of the first to twelfth inventions,
The gas supply amount control means has a function of changing a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the supply amount of the nitrogen gas and the supply amount of the halogen gas, during the film forming step,
The metal nitride film forming apparatus is characterized in that the metal nitride film formed on the substrate is a metal nitride film whose N / M ratio is changed inside the film.

  By utilizing the advantageous feature of supplying the nitrogen component of the metal nitride film as a gas state, the flow rate of the nitrogen gas is freely controlled, so that it cannot be realized by a film forming principle in which, for example, the nitrogen radical component is obtained from solid nitride. A metal nitride film having a changeable N / M ratio inside the film is formed.

The fourteenth invention (corresponding to claim 14)
In the metal nitride film manufacturing apparatus according to any one of the first to thirteenth inventions,
The metal capable of generating the high vapor pressure halide is any one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium, and hafnium.

The fifteenth invention (corresponding to claim 15)
In the metal nitride film manufacturing apparatus according to any one of the first to fourteenth inventions,
The metal nitride film manufacturing apparatus is characterized in that the halogen gas is chlorine gas.

Besides the halogen gas, fluorine (F ₂ ), bromine (Br ₂ ), iodine (I ₂ ), and the like can be applied. The halogen gas is desirably diluted, and the halogen gas concentration is diluted to 50% or less, preferably about 10%. At this time, helium gas, argon gas, etc. are mentioned as gas which dilutes halogen gas.

The sixteenth invention (corresponding to claim 16)
In the metal nitride film manufacturing apparatus according to any one of the first to fifteenth inventions,
Instead of the nitrogen gas supply means for supplying the nitrogen gas, an oxygen supply means or a carbon supply means for supplying oxygen or carbon is provided, and an oxidation or metal carbide film is formed on the substrate. Metal carbide film production equipment.

A metal nitride film forming method according to a seventeenth invention (corresponding to claim 17) for solving the above-mentioned problems is
Place the substrate on the support and place it in the chamber,
A precursor made of a metal halide formed of a metal capable of generating a high vapor pressure halide and etched with a halogen gas plasma obtained by plasmaizing a halogen gas into a member to be etched provided at a position facing the substrate. Produces
When the temperature of the substrate is made lower than the temperature of the member to be etched and the metal component of the precursor is formed on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting nitrogen gas into plasma. In the metal nitride film manufacturing method of forming a metal nitride film on the substrate,
In the metal nitride film manufacturing method, the supply amount of the nitrogen gas is controlled so that an N / M ratio, which is an atomic composition ratio between nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value.

The eighteenth invention (corresponding to claim 18)
In the metal nitride film manufacturing method according to the seventeenth invention,
The halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by electromagnetic waves from a planar coil disposed outside the insulating member that seals the upper surface of the chamber.
The metal nitride film manufacturing method is characterized in that the member to be etched is disposed between the substrate and the insulating member, and is formed into a shape that allows the precursor to be supplied to the substrate.

The nineteenth invention (corresponding to claim 19) is
In the metal nitride film manufacturing method according to the seventeenth invention,
The chamber has an upper surface sealed by the member to be etched,
The halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by electromagnetic waves from a coil wound around the chamber.

The twentieth invention (corresponding to claim 20) is
In the metal nitride film manufacturing method according to the seventeenth invention,
The support is grounded;
The chamber has an upper surface sealed by the member to be etched,
The method of producing a metal nitride film, wherein the halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by an electric field generated between the member to be etched and the support base. It is.

The twenty-first invention (corresponding to claim 21)
In the metal nitride film manufacturing method according to the seventeenth invention,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas plasma is generated in the upper chamber,
In the method of manufacturing a metal nitride film, the nitrogen gas plasma is generated in the lower chamber.

The twenty-second invention (corresponding to claim 22)
In the metal nitride film manufacturing method according to the seventeenth invention,
The metal nitride film manufacturing method is characterized in that a film is formed while raising and lowering the support base in the chamber.

The twenty-third invention (corresponding to claim 23)
In the metal nitride film manufacturing method according to the seventeenth invention,
In the method of manufacturing a metal nitride film, the halogen gas plasma and the nitrogen gas plasma are preliminarily converted into plasma outside the chamber body and supplied to the vicinity of the member to be etched.

The twenty-fourth invention (corresponding to claim 24)
In the metal nitride film manufacturing method according to the seventeenth invention,
The chamber has an upper surface sealed by the member to be etched,
The halogen gas plasma and the nitrogen gas plasma are converted into plasma by halogen gas and nitrogen gas supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. A method for producing a metal nitride film, characterized in that the plasma is plasmanized outside the chamber in advance and supplied to the vicinity of the member to be etched.

The twenty-fifth invention (corresponding to claim 25)
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-fourth inventions,
The method of producing a metal nitride film, wherein the nitrogen gas plasma is plasma that is preliminarily converted into plasma outside the chamber body and supplied to the upper surface of the substrate inside the chamber.

The twenty-sixth invention (corresponding to claim 26)
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-fourth inventions,
The nitrogen gas plasma is provided on the side wall of the chamber at substantially the same height as the substrate, and is supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. The method is a metal nitride film manufacturing method characterized in that the nitrogen gas is plasmatized in advance outside the chamber and supplied to the upper surface of the substrate inside the chamber.

The twenty-seventh invention (corresponding to claim 27)
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-sixth inventions,
The N / M ratio is a method for producing a metal nitride film, wherein the N / M ratio is greater than 0 and 1 or less.

The twenty-eighth invention (corresponding to claim 28)
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-seventh inventions,
The supply amount of the nitrogen gas is a metal nitride film manufacturing method characterized in that a nitrogen gas / halogen gas flow rate ratio, which is a ratio to the supply amount of the halogen gas, is greater than 0 and 0.1 or less.

The twenty-ninth invention (corresponding to claim 29)
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-eighth inventions,
During the film forming process, a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the nitrogen gas supply amount and the halogen gas supply amount, is changed to obtain a metal nitride film in which the N / M ratio is changed inside the film. A metal nitride film manufacturing method characterized by forming a film.

The thirtieth invention (corresponding to claim 30) is
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-ninth inventions,
The metal capable of generating the high vapor pressure halide is any one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium, and hafnium.

The thirty-first invention (corresponding to claim 31) is
In the metal nitride film manufacturing method according to any one of the seventeenth to thirtieth inventions,
In the method of manufacturing a metal nitride film, the halogen gas is chlorine gas.

A thirty-second invention (corresponding to claim 32) is
In the metal nitride film manufacturing method according to any one of the seventeenth to thirty-first inventions,
In this method, an oxygen or carbon carbide film is formed by supplying oxygen or carbon instead of the nitrogen gas and forming an oxide or metal carbide film on the substrate.

A metal nitride film according to a thirty-third invention (corresponding to claim 33) for solving the above-mentioned problems,
This is a metal nitride film in which the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, is controlled.

A metal nitride film according to a thirty-fourth aspect of the invention for solving the above problems (corresponding to claim 34),
This is a metal nitride film in which the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, is controlled to be greater than 0 and 1 or less.

A thirty-fifth aspect of the invention (corresponding to claim 35) is
In the metal nitride film according to the thirty-third or thirty-fourth invention,
The metal nitride film is characterized in that the N / M ratio changes inside the film.

A thirty-sixth aspect of the invention (corresponding to claim 36) is
A member to be etched formed of a metal capable of generating a high vapor pressure halide is etched with halogen gas plasma to generate a precursor made of a metal halide,
When forming the metal component of the precursor on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting nitrogen gas with a controlled supply amount into plasma, and the substrate is formed on the substrate. A metal nitride film according to any one of the thirty-third to thirty-fifth inventions.

According to the metal nitride film forming apparatus of the first invention,
A chamber in which the substrate is accommodated, a support base on which the substrate is placed,
A member to be etched formed of a metal capable of generating a high vapor pressure halide and provided at a position facing the substrate;
Halogen gas supply means for supplying halogen gas to the chamber;
Nitrogen gas supply means for supplying nitrogen gas to the chamber;
Plasma generating means for generating halogen gas plasma and nitrogen gas plasma by converting the halogen gas and nitrogen gas into plasma;
Temperature control means for lowering the temperature of the substrate lower than the temperature of the member to be etched,
The member to be etched is etched with the halogen gas plasma to generate a precursor made of a metal halide, and the metal component is nitrided with the nitrogen gas plasma when the metal component of the precursor is formed on the substrate. In the metal nitride film manufacturing apparatus for forming a metal nitride film on the substrate,
Since the gas supply amount control means for controlling the supply amount of the nitrogen gas is provided so that the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value,
The apparatus for carrying out the metal nitride film manufacturing method according to the seventeenth aspect of the invention can be provided, and the N / M ratio can be freely controlled over a wide range by freely controlling the supply amount of nitrogen gas.

  The ability to form a metal nitride film whose N / M ratio is freely controlled over a wide range means that, for example, a metal nitride film whose work function is freely controlled can be formed. Therefore, for example, by using a metal nitride film whose work function is freely controlled for the gate electrode of the transistor, an optimum transistor can be manufactured regardless of the transistor structure and transistor characteristics.

  In addition, the metal nitride film forming apparatus according to the first invention has solved the problems of film quality deterioration due to the inclusion of impurities and the problem that uniform film formation in a complicated shape is difficult due to the film formation principle. It is possible to form a film, and it is possible to form a film without fear of causing electrical damage to the film formation substrate or the film itself.

According to the metal nitride film forming apparatus of the second invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed with an insulating member,
The plasma generating means comprises a planar coil disposed outside the insulating member and a power supply unit for supplying power to the coil.
Since the member to be etched is installed between the substrate and the insulating member, and the precursor is formed in a shape that can be supplied to the substrate,
In addition to the effect of the first invention, it is possible to provide a device for carrying out the metal nitride film manufacturing method according to the eighteenth aspect of the invention. When each gas is supplied from the chamber side wall to the inside, a sufficient installation space for the gas supply device can be secured. Further, it is possible to uniformly form a metal nitride film on the substrate by controlling the plasma acting on the surface of the member to be etched and controlling the generation of the precursor.

According to the metal nitride film creating apparatus of the third invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed by the member to be etched,
Since the plasma generating means comprises a coil wound around the chamber and a power supply unit for supplying power to the coil.
In addition to the effect of the first invention, in addition to the effect produced by the metal nitride film manufacturing method according to the nineteenth invention, in addition, by generating electromagnetic waves from a coil installed around the chamber, The gas supplied into the chamber can be turned into plasma without making the member to be etched into a complicated shape. In addition, the configuration of the upper surface of the chamber is simplified, and maintenance can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film forming apparatus of the fourth invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The support is grounded;
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes the member to be etched, a power supply unit that supplies power to the member to be etched, and the grounded support base, and generates gas plasma between the member to be etched and the support base.
In addition to the effect of the first invention, the member to be etched itself can be used as an electrode for plasma generation, in addition to the effect produced by the metal nitride film manufacturing method according to the twentieth invention. A plasma antenna in the upper part of the chamber and around the cylindrical part is not necessary, and the degree of freedom of the configuration around the apparatus can be increased. In addition, the configuration of the upper surface of the chamber is simplified, and maintenance can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film creating apparatus of the fifth invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas supply means is provided in the upper chamber,
The nitrogen gas supply means is provided in the lower chamber,
Since the plasma generating means is provided in each of the upper chamber and the lower chamber,
In addition to the effect of the first invention, a halogen gas plasma is further generated in one chamber, so that the plasma for the substrate can be obtained. Can be minimized.

According to the metal nitride film creating apparatus of the sixth invention,
In the metal nitride film manufacturing apparatus according to the first invention,
Since it has an elevating drive means for elevating the support base inside the chamber,
In addition to the effect of the first invention, in addition to the effect of the first invention, a state in which halogen gas plasma is generated by raising and lowering the support base, and the metal nitride film manufacturing method according to the twenty-second invention, The state in the chamber is changed to a state in which halogen gas plasma and nitrogen gas plasma or nitrogen gas plasma is generated, so that halogen radicals and nitrogen radicals can be generated accurately.

According to the metal nitride film creating apparatus of the seventh invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The plasma generation means is configured as an external plasma generation means outside the chamber body, and the halogen gas supply means and the nitrogen gas supply means supply the halogen gas and the nitrogen gas to the external plasma generation means. ,
The halogen gas plasma and the nitrogen gas plasma are converted into plasma by the external plasma generating means in advance outside the chamber body, and supplied to the vicinity of the member to be etched.
In addition to the effect of the first invention, gas plasma can be generated in an external plasma generating means isolated from the chamber. Therefore, it is possible to suppress the possibility that the substrate is directly exposed to the plasma, thereby suppressing the damage caused by the plasma. For example, in the case where film formation is further performed on a substrate on which a film of another material has already been formed, the second film formation can be performed without damaging the film of the material already formed. In addition, the configuration of the upper surface of the chamber is simplified, and maintenance can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film creating apparatus of the eighth invention,
In the metal nitride film manufacturing apparatus according to the first invention,
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil, and is an external plasma installed outside the chamber body. Configured as a generating means,
The halogen gas supply means supplies halogen gas to the cylindrical passage,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The halogen gas plasma and the nitrogen gas plasma are plasmas that are preliminarily converted to the outside of the chamber main body by the external plasma generating means and supplied to the vicinity of the member to be etched.
In addition to the effect achieved by the first invention, the apparatus can be used to perform the metal nitride film manufacturing method according to the twenty-fourth invention, and further, gas plasma can be generated in an external plasma generating means isolated from the chamber. Therefore, it is possible to suppress the possibility that the substrate is directly exposed to the plasma, thereby suppressing the damage caused by the plasma. For example, in the case where film formation is further performed on a substrate on which a film of another material has already been formed, the second film formation can be performed without damaging the film of the material already formed. In addition, the configuration of the upper surface of the chamber is simplified, and maintenance can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film creating apparatus of the ninth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to eighth inventions,
A second external plasma generation unit provided on a side wall of the chamber at substantially the same height as the substrate; the nitrogen gas supply unit supplies the nitrogen gas to the second external plasma generation unit;
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generation means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber.
The metal nitride film manufacturing method according to the twenty-fifth aspect of the invention can be implemented, and in addition to the effects exhibited by any of the first to eighth aspects of the invention, the apparatus is further installed at substantially the same height as the substrate. By supplying nitrogen gas from the second external plasma generating means to the upper surface of the substrate as nitrogen gas plasma, it is possible to eliminate the possibility of passivation of the member to be etched by nitrogen radicals. Thereby, a metal nitride film in which the N / M ratio is controlled with higher accuracy can be formed.

  Further, by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate, the occurrence rate of nitriding reaction in the vicinity of the substrate can be increased, and a metal nitride film having a relatively high N / M ratio can be efficiently formed. .

According to the metal nitride film forming apparatus of the tenth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to eighth inventions,
A first passage is provided on a side wall of the chamber at substantially the same height as the substrate, and includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil. Two external plasma generating means,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generation means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber.
The metal nitride film manufacturing method according to the twenty-sixth aspect of the invention can be provided, and in addition to the effects of any of the first to eighth aspects of the invention, the apparatus is further installed at substantially the same height as the substrate. By supplying nitrogen gas from the second external plasma generating means to the upper surface of the substrate as nitrogen gas plasma, it is possible to eliminate the possibility of passivation of the member to be etched by nitrogen radicals. Thereby, a metal nitride film in which the N / M ratio is controlled with higher accuracy can be formed.

  Further, by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate, the occurrence rate of nitriding reaction in the vicinity of the substrate can be increased, and a metal nitride film having a relatively high N / M ratio can be efficiently formed. .

According to the metal nitride film forming apparatus of the eleventh invention,
In the metal nitride film manufacturing apparatus according to any one of the first to tenth inventions,
Since the N / M ratio is greater than 0 and less than or equal to 1,
The metal nitride film manufacturing method according to the twenty-seventh aspect of the invention can be provided as an apparatus, and in addition to the effects of any of the first to tenth aspects of the invention, for example, a gate electrode film of a transistor, etc. A metal nitride film with high availability can be formed.

According to the metal nitride film creating apparatus of the twelfth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to eleventh inventions,
The supply amount of nitrogen gas controlled by the gas supply amount control means is such that the nitrogen gas / halogen gas flow rate ratio, which is the ratio to the supply amount of the halogen gas, is greater than 0 and less than or equal to 0.1.
In addition to the effect of any one of the first to eleventh inventions, the N / M ratio is more than 0 and 1 or less. A metal nitride film that is freely controlled can be formed.

  The nitrogen gas supply amount is controlled not only by the nitrogen gas / halogen gas flow rate ratio being a ratio to the halogen gas supply amount being greater than 0 and not more than 0.1, but also greater than 0 and not more than 0.05 or 0. The metal nitride film can be formed in such a manner that the N / M ratio is freely controlled to be greater than 0 and less than or equal to 1 by controlling within this range.

  In particular, by controlling the nitrogen gas / halogen gas flow rate ratio within the range of 0.005 or more and 0.025 or less, the linear correspondence relationship between the nitrogen gas / halogen gas flow rate ratio and the N / M ratio can be utilized. Film formation with higher ratio accuracy can be performed.

According to the metal nitride film forming apparatus of the thirteenth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to twelfth inventions,
The gas supply amount control means has a function of changing a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the supply amount of the nitrogen gas and the supply amount of the halogen gas, during the film forming step,
Since the metal nitride film formed on the substrate is a metal nitride film having an N / M ratio changed inside the film,
In addition to the effect of any one of the first to twelfth inventions, the nitrogen component of the metal nitride film can be further changed to a gas state. By utilizing the advantageous feature of supplying the nitrogen gas flow rate freely, for example, the N / M ratio inside the film cannot be realized by the film forming principle in which the nitrogen radical component is obtained from solid nitride. It is possible to form a metal nitride film having a changed thickness. For example, a metal nitride film in which the N / M ratio is continuously, intermittently or stepwise changed can be formed inside the metal nitride film.

According to the metal nitride film forming apparatus of the fourteenth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to thirteenth inventions,
Since the metal capable of generating the high vapor pressure halide is one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium or hafnium,
In addition to the effect of any one of the first to thirteenth inventions, a tantalum nitride, titanium nitride, tungsten nitride, or nitride can be provided. A metal nitride film having high industrial applicability such as molybdenum can be formed.

According to the metal nitride film forming apparatus of the fifteenth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to fourteenth inventions,
Since the halogen gas is chlorine gas,
An apparatus for carrying out the metal nitride film manufacturing method according to the thirty-first invention can be provided, and in addition to the effects exhibited by any of the first to fourteenth inventions, a balance of reactivity, manufacturing cost, etc. is further taken into consideration. By using the halogen gas, optimum film formation can be performed.

According to the metal nitride film forming apparatus of the sixteenth invention,
In the metal nitride film manufacturing apparatus according to any one of the first to fifteenth inventions,
Instead of the nitrogen gas supply means for supplying the nitrogen gas, it has an oxygen supply means or a carbon supply means for supplying oxygen or carbon, and an oxide or metal carbide film is formed on the substrate.
In addition to the effect of any one of the first to fifteenth inventions, a thin film having a controlled oxygen / metal ratio can be obtained. Form a film to use as a gate electrode, a dielectric for capacitance, a catalyst (for example, titania as a photocatalyst), an adhesion layer, etc., or form a thin film with a controlled carbon / metal ratio to form a protective film or etching stop film And so on.

According to the method for producing a metal nitride film according to the seventeenth invention,
Place the substrate on the support and place it in the chamber,
A precursor made of a metal halide formed of a metal capable of generating a high vapor pressure halide and etched with a halogen gas plasma obtained by plasmaizing a halogen gas into a member to be etched provided at a position facing the substrate. Produces
When the temperature of the substrate is made lower than the temperature of the member to be etched and the metal component of the precursor is formed on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting nitrogen gas into plasma. In the metal nitride film manufacturing method of forming a metal nitride film on the substrate,
Since the supply amount of the nitrogen gas is controlled so that the N / M ratio, which is the atomic composition ratio between nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value,
The N / M ratio can be freely controlled over a wide range by freely controlling the nitrogen gas supply amount.

  The ability to form a metal nitride film whose N / M ratio is freely controlled over a wide range means that, for example, a metal nitride film whose work function is freely controlled can be formed. Therefore, for example, by using a metal nitride film whose work function is freely controlled for the gate electrode of the transistor, an optimum transistor can be manufactured regardless of the transistor structure and transistor characteristics.

  In addition, the metal nitride film forming method according to the seventeenth invention has solved the problem of film quality deterioration due to the inclusion of impurities and the problem that uniform film formation in a complicated shape is difficult due to the film formation principle. It is possible to form a film, and it is possible to form a film without fear of causing electrical damage to the film formation substrate or the film itself.

According to the metal nitride film forming method of the eighteenth aspect of the invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
The halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by electromagnetic waves from a planar coil disposed outside the insulating member that seals the upper surface of the chamber.
Since the member to be etched is installed between the substrate and the insulating member, and the precursor is formed in a shape that can be supplied to the substrate,
In addition to the effects of the seventeenth aspect of the invention, by securing a space around the cylindrical portion of the chamber, for example, when each gas is supplied from the chamber side wall to the inside, a sufficient space for installing the gas supply device is secured. can do. Further, it is possible to uniformly form a metal nitride film on the substrate by controlling the plasma acting on the surface of the member to be etched and controlling the generation of the precursor.

According to the metal nitride film forming method of the nineteenth invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
The chamber has an upper surface sealed by the member to be etched,
The halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by electromagnetic waves from a coil wound around the chamber.
In addition to the effect of the seventeenth invention, the gas supplied into the chamber is converted into plasma without making the member to be etched into a complicated shape by generating electromagnetic waves from a coil installed around the chamber. can do. Further, the configuration of the upper surface of the chamber is simplified, and maintenance of an apparatus for performing the method of the present invention can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film forming method of the twentieth invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
The support is grounded;
The chamber has an upper surface sealed by the member to be etched,
Since the halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by an electric field generated between the member to be etched and the support base,
In addition to the effect exhibited by the seventeenth invention, the member to be etched itself is used as an electrode for plasma generation, thereby eliminating the need for a plasma antenna in the upper part of the chamber and around the cylindrical part, and implementing the present invention. The degree of freedom of surrounding configuration can be increased. Further, the configuration of the upper surface of the chamber is simplified, and maintenance of an apparatus for performing the method of the present invention can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film forming method of the twenty-first invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas plasma is generated in the upper chamber,
Since the nitrogen gas plasma is generated in the lower chamber,
In addition to the effect exhibited by the seventeenth invention, the halogen gas plasma is generated in one chamber, so that the influence of the plasma on the substrate can be minimized.

According to the metal nitride film forming method of the twenty-second invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
Since the film is formed while raising and lowering the support base inside the chamber,
In addition to the effect of the seventeenth invention, the chamber is further divided into a state in which halogen gas plasma is generated and a state in which halogen gas plasma and nitrogen gas plasma or nitrogen gas plasma are generated by raising and lowering the support base. The state can be changed, and a halogen radical and a nitrogen radical can be generated accurately.

According to the metal nitride film forming method of the twenty-third invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
Since the halogen gas plasma and the nitrogen gas plasma are preliminarily converted into plasma outside the chamber body and supplied to the vicinity of the member to be etched,
In addition to the effects exhibited by the seventeenth aspect of the invention, further, by generating gas plasma outside the chamber, it is possible to suppress the possibility that the substrate is directly exposed to the plasma, thereby suppressing damage caused by the plasma. . For example, in the case where film formation is further performed on a substrate on which a film of another material has already been formed, the second film formation can be performed without damaging the film of the material already formed. Further, the configuration of the upper surface of the chamber is simplified, and maintenance of an apparatus for performing the method of the present invention can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film forming method of the twenty-fourth invention,
In the metal nitride film manufacturing method according to the seventeenth invention,
The chamber has an upper surface sealed by the member to be etched,
The halogen gas plasma and the nitrogen gas plasma are converted into plasma by halogen gas and nitrogen gas supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. Since it is plasma that is preliminarily converted into plasma outside the chamber and supplied in the vicinity of the member to be etched,
In addition to the effects exhibited by the seventeenth aspect of the invention, further, by generating gas plasma outside the chamber, it is possible to suppress the possibility that the substrate is directly exposed to the plasma, thereby suppressing damage caused by the plasma. . For example, in the case where film formation is further performed on a substrate on which a film of another material has already been formed, the second film formation can be performed without damaging the film of the material already formed. Further, the configuration of the upper surface of the chamber is simplified, and maintenance of an apparatus for performing the method of the present invention can be improved, for example, replacement of a member to be etched which is a consumable member is simplified.

According to the metal nitride film forming method of the twenty-fifth invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-fourth inventions,
Since the nitrogen gas plasma is plasma that is preliminarily formed outside the chamber body and is supplied to the upper surface of the substrate inside the chamber,
In addition to the effect of any one of the seventeenth to twenty-fourth inventions, by supplying nitrogen gas to the upper surface of the substrate as nitrogen gas plasma, the possibility of passivation of the member to be etched by nitrogen radicals is eliminated. Can do. Thereby, a metal nitride film in which the N / M ratio is controlled with higher accuracy can be formed.

  Further, by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate, the occurrence rate of nitriding reaction in the vicinity of the substrate can be increased, and a metal nitride film having a relatively high N / M ratio can be efficiently formed. .

According to the metal nitride film forming method of the twenty-sixth aspect of the invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-fourth inventions,
The nitrogen gas plasma is provided on the side wall of the chamber at substantially the same height as the substrate, and is supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. By converting the nitrogen gas into plasma, it is plasma that has been converted into plasma outside the chamber and supplied to the upper surface of the substrate inside the chamber.
In addition to the effects exhibited by any one of the seventeenth to twenty-fourth inventions, the nitrogen gas is supplied to the upper surface of the substrate as nitrogen gas plasma from substantially the same height as the substrate, so that the member to be etched by nitrogen radicals can be prevented. The fear of mobilization can be eliminated. Thereby, a metal nitride film in which the N / M ratio is controlled with higher accuracy can be formed.

  Further, by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate, the occurrence rate of nitriding reaction in the vicinity of the substrate can be increased, and a metal nitride film having a relatively high N / M ratio can be efficiently formed. .

According to the metal nitride film forming method of the twenty-seventh aspect of the invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-sixth inventions,
Since the N / M ratio is greater than 0 and less than or equal to 1,
In addition to the effects of any of the seventeenth to twenty-sixth inventions, a metal nitride film having high industrial applicability, such as a gate electrode film of a transistor, can be formed.

According to the metal nitride film forming method of the twenty-eighth aspect of the invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-seventh inventions,
Since the supply amount of the nitrogen gas is such that the nitrogen gas / halogen gas flow rate ratio, which is the ratio of the supply amount of the halogen gas, is greater than 0 and 0.1 or less,
In addition to the effects exhibited by any one of the seventeenth to twenty-seventh inventions, a metal nitride film can be formed in which the N / M ratio is freely controlled to be greater than 0 and less than or equal to 1.

  The nitrogen gas supply amount is controlled not only by the nitrogen gas / halogen gas flow rate ratio being a ratio to the halogen gas supply amount being greater than 0 and not more than 0.1, but also greater than 0 and not more than 0.05 or 0. The metal nitride film can be formed in such a manner that the N / M ratio is freely controlled to be greater than 0 and less than or equal to 1 by controlling within this range.

  In particular, by controlling the nitrogen gas / halogen gas flow rate ratio within the range of 0.005 or more and 0.025 or less, the linear correspondence relationship between the nitrogen gas / halogen gas flow rate ratio and the N / M ratio can be utilized. Film formation with higher ratio accuracy can be performed.

According to the metal nitride film forming method of the twenty-ninth invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-eighth inventions,
During the film forming process, a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the nitrogen gas supply amount and the halogen gas supply amount, is changed to obtain a metal nitride film in which the N / M ratio is changed inside the film. Since we decided to form a film,
In addition to the effect exhibited by any of the seventeenth to twenty-eighth inventions, the nitrogen gas flow rate can be freely controlled by utilizing the advantageous feature of supplying the nitrogen component of the metal nitride film as a gas state. For example, it is possible to form a metal nitride film having an N / M ratio changed inside the film, which cannot be realized by a film forming principle in which a nitrogen radical component is obtained from solid nitride. For example, a metal nitride film in which the N / M ratio is continuously, intermittently or stepwise changed can be formed inside the metal nitride film.

According to the metal nitride film forming method of the thirtieth invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to twenty-ninth inventions,
Since the metal capable of generating the high vapor pressure halide is one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium or hafnium,
In addition to the effects exhibited by any of the seventeenth to twenty-ninth inventions, a metal nitride film having a high industrial applicability, such as tantalum nitride, titanium nitride, tungsten nitride, or molybdenum nitride, can be formed.

According to the metal nitride film forming method of the thirty-first invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to thirtieth inventions,
Since the halogen gas is chlorine gas,
In addition to the effects exhibited by any of the seventeenth to thirtieth inventions, optimum film formation can be performed by using a halogen gas that takes into account the balance of reactivity, manufacturing cost, and the like.

According to the metal nitride film forming method of the thirty-second invention,
In the metal nitride film manufacturing method according to any one of the seventeenth to thirty-first inventions,
Since oxygen or carbon is supplied instead of the nitrogen gas, and an oxide or metal carbide film is formed on the substrate,
In addition to the effect of any one of the seventeenth to thirty-first aspects, a thin film with a controlled oxygen / metal ratio is further formed to form a gate electrode, a dielectric for capacitance, a catalyst (for example, titania which is a photocatalyst), It can be used as an adhesion layer or the like, or a thin film with a controlled carbon / metal ratio can be formed and used as a protective film or an etching stop film.

According to the metal nitride film of the thirty-third invention,
Since the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, was controlled,
For example, a metal nitride film whose work function is freely controlled can be used. For example, by using it as a gate electrode of a transistor, an optimum transistor can be manufactured regardless of the transistor structure and transistor characteristics.

According to the metal nitride film of the 34th invention,
Since the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, was controlled to be greater than 0 and less than or equal to 1,
For example, a metal nitride film having high industrial applicability such as a gate electrode film of a transistor can be used.

According to the metal nitride film according to the thirty-fifth aspect of the present invention,
In the metal nitride film according to the thirty-third or thirty-fourth invention,
Because the N / M ratio has changed inside the film,
For example, a metal nitride film that cannot be realized by a film forming principle in which a nitrogen radical component is obtained from solid nitride can be obtained.

According to the metal nitride film according to the thirty-sixth aspect of the invention,
A member to be etched formed of a metal capable of generating a high vapor pressure halide is etched with halogen gas plasma to generate a precursor made of a metal halide,
When the metal component of the precursor is formed on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting the supply amount of nitrogen gas into plasma, and is formed on the substrate. Since it was decided to be a metal nitride film according to any of the inventions,
Based on the principle of film formation, it is possible to obtain a metal nitride film that solves the problem of film quality deterioration due to the inclusion of impurities and the problem that uniform film formation in a complicated shape is difficult. It is possible to form a metal nitride film that eliminates the risk of electrical damage to the film itself.

  The metal nitride film according to the present invention has high industrial applicability, such as a gate electrode film of a transistor, for example, a metal nitride film in which the N / M ratio is changed inside the film, such as a nitrogen radical component as a solid nitride This film cannot be realized by the film formation principle obtained from the above.

<First Embodiment>
A metal nitride film manufacturing method and a metal nitride film manufacturing apparatus according to the first embodiment will be described with reference to FIG. FIG. 1 is a schematic internal configuration diagram of a metal nitride film production apparatus for performing the metal nitride film production method according to the first embodiment of the present invention. In the figure, a part of the concept of the film formation reaction in the metal nitride film forming process is also shown.

<About the overall configuration of the device>
As shown in FIG. 1, a support base 2 is provided in the vicinity of the bottom of the chamber 1 formed in a cylindrical shape, and a substrate 3 is placed on the support base 2. The support table 2 is provided with a temperature controller 6 including a heater 4 and a refrigerant flow path 5. The support table 2 is set at a predetermined temperature (for example, a temperature at which the substrate 3 is maintained at 100 ° C. to 200 ° C.) by the temperature controller 6. ) Is controlled.

  The upper surface of the chamber 1 is an opening, and the opening is closed by a plate-like ceiling plate 7 made of an insulating material (for example, made of ceramics). The inside of the chamber 1 closed by the ceiling plate 7 is maintained at a predetermined pressure by the vacuum device 8.

<About plasma generator>
A plasma antenna 9 for converting the inside of the chamber 1 into plasma is provided above the ceiling plate 7, and the plasma antenna 9 is a planar coil parallel to the surface of the ceiling plate 7. The planar coil means a shape in which the planar shape of the plasma antenna 9 is, for example, a spiral shape. A matching unit 10 and a power source 11 are connected to the plasma antenna 9 and supplied with a high frequency current. The plasma antenna 9, the matching unit 10, and the power source 11 constitute a plasma generator that is a plasma generating unit.

<About gas supply>
Above the side wall of the chamber 1 is a nozzle 12 having a function of supplying chlorine gas as a halogen gas (halogen gas supply means) and a function of supplying nitrogen gas (nitrogen gas supply means) into the chamber 1. It is connected. Chlorine gas supplied into the chamber 1 is diluted with helium gas. A gas or the like that is supplied into the chamber 1 and does not participate in film formation is exhausted from the exhaust port 15.

As the halogen gas, fluorine (F ₂ ), bromine (Br ₂ ), iodine (I ₂ ), or the like can be used. The gas for diluting the halogen gas may be argon gas or the like in addition to helium gas, and the halogen gas concentration is preferably 50% or less, preferably about 10%.

  One or a plurality of nozzles 12 are arranged in the circumferential direction of the chamber 1 and open toward the inside of the chamber 1, and chlorine gas and nitrogen gas diluted via a flow rate controller 13 are supplied to the nozzle 12. Sent. Depending on the arrangement of the nozzles 12, the film thickness distribution of the metal nitride film 18 to be formed may be affected.

The flow rate controller 13 has a function as a gas supply amount control means, and independently adjusts the supply amount of chlorine gas and the supply amount of nitrogen gas, and N ₂ which is the supply amount of nitrogen gas with respect to the supply amount of chlorine gas. / Cl ₂ gas flow rate ratio is controlled. Moreover, it has the function which can adjust independently the supply amount of helium gas, argon gas, etc. which dilute chlorine gas.

  In the present embodiment, an example in which both chlorine gas and nitrogen gas are supplied from the same nozzle 12 is shown, but a nozzle dedicated to each gas may be installed. For example, a configuration in which a plurality of nozzles arranged in the circumferential direction of the chamber 1 are alternately used as nozzles dedicated to each gas in the circumferential direction can be mentioned.

<About the member to be etched>
A member to be etched 14 made of tantalum (Ta), which is a metal capable of forming a high vapor pressure halide, is held above the chamber 1 (below the nozzle 12). The member to be etched 14 is electrically connected to the plasma antenna 9. It is arrange | positioned in the discontinuous state between the board | substrate 3 and the ceiling board 7 with respect to the flow of this.

  For example, as shown in FIG. 9, the member 14 to be etched is provided with an annular ring member 14a formed of an insulator, and a plurality of members 14a provided in the circumferential direction of the ring member 14a and extending to the center of the ring member 14a. The bar member 14b is formed, and a space 14c is formed between the bar members 14b. As a result, the member 14 to be etched is structurally discontinuous with respect to the circumferential direction, which is the electricity flow direction of the plasma antenna 8.

  Note that the configuration of discontinuity with respect to the electric flow of the plasma antenna 9 is not limited to the shape shown in FIG. 9, but a lattice-like member to be etched, a mesh-like member to be etched, or a slit shape Or a member to be etched having a notch (space). In this embodiment, tantalum (Ta) is used as the material of the member 14 to be etched. However, the material is not limited to this, and titanium (Ti), tungsten (W), molybdenum (Mo) is used depending on the metal nitride film to be formed. , Vanadium, niobium, zirconium, hafnium, or the like.

<Deposition of Metal Nitride Film Using the Deposition Apparatus>
FIG. 10 is a diagram illustrating a method for controlling each gas flow rate when the metal nitride film manufacturing method according to the present embodiment is performed. This figure shows the control of each gas flow rate with the horizontal axis as the time axis. As shown in the figure, the metal nitride film manufacturing method according to the present embodiment includes a preheating process and a film forming process. Hereinafter, a method for forming a metal nitride film having a controlled N / M ratio by the above-described metal nitride film manufacturing apparatus will be described in detail with reference to FIGS.

<Preheating process>
First, a predetermined amount of helium gas is supplied into the chamber 1 from the nozzle 12 via the flow rate controller 13 for a predetermined time (from time zero to time t1), and electromagnetic waves are transmitted from the plasma antenna 9 into the chamber 1. When incident, helium gas is excited to generate helium gas plasma. Helium gas plasma is generated in the region shown by the gas plasma 16. The reaction at this time can be shown by the following formula.

He → He ^* (1)
Here, He ^* represents a helium radical.

  The member to be etched 14 is heated by the generated helium gas plasma. This step is a preheating step for heating the member 14 to be etched with helium gas plasma and performing a subsequent etching reaction to lubrication.

  Next, in the second half of the preheating process (from time t1 to time t2), the gas flow rate is gradually increased from the nozzle 12 into the chamber 1 through the flow rate controller 13 while the electromagnetic wave is incident from the plasma antenna 9. Then, helium gas, chlorine gas and nitrogen gas are supplied. As a result, chlorine gas and nitrogen gas are excited, and chlorine gas plasma and nitrogen gas plasma are generated. These gas plasmas are generated in the region shown by the gas plasma 16. The reaction at this time can be shown by the following formula.

Cl ₂ → 2Cl ^* (2)
N ₂ → 2N ^* (3)
Here, Cl ^* represents a chlorine radical, and N ^* represents a nitrogen radical.

In this embodiment, the flow rate of each gas is gradually increased so that the flow rate ratio of helium gas: chlorine gas: nitrogen gas is about 100: 33: 1 (for example, 100 sccm: 33 sccm: 1 sccm) at time t2. That is, in the film-forming process described later, the supplied chlorine gas was a chlorine gas diluted with helium gas to a concentration of about 25%, and the N ₂ / Cl ₂ gas flow rate ratio was 0.03.

The N ₂ / Cl ₂ gas flow rate ratio in the film forming process is not limited to 0.03, and can be freely set within a range from 0 to 0.1 as will be described in detail below. By setting the N ₂ / Cl ₂ gas flow rate ratio to a predetermined value in this range, the N / M ratio of the deposited metal nitride film 18 can be freely controlled in the range from 0 to 1 or less.

  In the second half of this preheating step, in addition to preheating the member 14 to be etched, it also serves the purpose of adjusting the gas flow rate required for film formation. The supply amount and supply time of the helium gas supplied in the preheating step are set so that the member to be etched 14 is heated to a predetermined temperature. Further, the chlorine gas and the nitrogen gas supplied in the second half of the preheating step control the supply speed in consideration of items such as the contribution to the heating of the member 14 to be etched by the gas plasma and the stability of the gas supply. .

<About Faraday Shield>
In the metal nitride film manufacturing apparatus shown in FIG. 1, a member 14 to be etched, which is a conductor, exists under the plasma antenna 9. However, the gas plasma 16 stably covers the member 14 to be etched, that is, the gas plasma 16 is stably generated also under the member 14 to be etched by the following action. As a result, the generated precursor 17 can be supplied to the substrate 3.

  As described above, the rod member 14b of the member 14 to be etched is disposed between the substrate 3 and the ceiling plate 7 so as to be discontinuous with respect to the flow direction of the current flowing through the plasma antenna 9 (FIG. 9).

  When a current flows through the plasma antenna 9 having a planar coil, an induced current in a direction opposite to the current flow direction of the plasma antenna 9 is generated on the surface of each rod member 14b facing the plasma antenna 9. Since the space 14c exists in the member 14 to be etched, the induced current generated in the bar member 14b flows to the lower surface (the surface on the back side of the facing surface) of each bar member 14b. Therefore, the flow direction of the induced current on the lower surface is the same as the flow direction of the current flowing through the plasma antenna 9 (Faraday shield).

  That is, when the member 14 to be etched is viewed from the substrate 3 side, there is no induced current in a direction that cancels the current flowing through the plasma antenna 9. Further, the ring member 14a is grounded, and each bar member 14b is maintained at the same potential. As a result, even if the member 14 to be etched is present, the electromagnetic wave reliably enters the chamber 1 from the plasma antenna 9, and the gas plasma 16 is stably generated below the member 14 to be etched. It is supposed to be. As a result, the generated precursor 17 can be supplied to the substrate 3.

<Deposition process>
Next, in the film formation process from time t2, film formation is performed while maintaining the respective gas flow rate ratios reached at time t2. That is, the film forming process is performed while maintaining the flow ratio of helium gas: chlorine gas: nitrogen gas at about 100: 33: 1.

As described above, the etching reaction occurs in the member 14 to be etched by the chlorine gas plasma generated in the region indicated by the gas plasma 16. The reaction at this time can be shown by the following formula.
Ta (s) + XCl ^* → TaCl _x (g) (4)
Here, s represents a solid state, g represents a gas state, and X represents a number greater than zero (not limited to an integer). Expression (4) shows a state in which the tantalum component of the member to be etched 14 is etched by chlorine radicals to generate tantalum chloride gas that is a high vapor pressure halide. This tantalum chloride gas is the precursor 17.

The member 14 to be etched is heated by the generation of the gas plasma 16, and the substrate 3 is cooled by the temperature controller 6, whereby the temperature of the substrate 3 becomes lower than the temperature of the member 14 to be etched. Further, since each gas is supplied from the nozzle 12 and exhausted from the exhaust port 15 inside the chamber 1, the flow direction of each gas is a direction from the upper side to the lower side of the chamber 1. As a result, the precursor 17 is adsorbed on the substrate 3. The reaction at this time can be shown by the following formula.
TaCl _x (g) → TaCl _x (ad) (5)
Here, ad indicates an adsorption state.

The tantalum chloride adsorbed on the substrate 3 is reduced and nitrided by chlorine radicals and nitrogen radicals to become tantalum nitride, and a metal nitride film 18 is formed. The reaction at this time can be shown by the following formula.
TaCl _X (ad) + XCl ^* + YN ^* → TaN _Y (s) + XCl ₂ ↑ (6)
Here, Y represents a number greater than zero (not limited to an integer).

The film formation reaction of the above formula (6) is considered to consist of the following two reactions. The first reaction is a reaction in which tantalum chloride adsorbed on the substrate 3 is reduced by chlorine radicals to become a tantalum component and then nitrided by nitrogen radicals to become tantalum nitride. This reaction can be shown by the following formula.
TaCl _x (ad) + XCl ^* → Ta (s) + XCl ₂ ↑ (7)
Ta (s) + YN ^* → TaN _Y (s) (8)

The second reaction is a reaction in which tantalum chloride adsorbed on the substrate 3 is directly nitrided by nitrogen radicals to become tantalum nitride. This reaction can be shown by the following formula.
TaCl _X (ad) + YN ^* → TaN _Y (s) + X / 2Cl ₂ ↑ (9)

  Further, a part of the tantalum chloride gas generated in the above formula (4) is reduced to a tantalum component by being reduced by chlorine radicals before adsorbing to the substrate 3 (see the above formula (5)), and then nitrogen. It is considered that there are cases in which nitridation is caused by radicals to become gas tantalum nitride, or nitridation is directly caused by nitrogen radicals to become gas tantalum nitride. The gas-state tantalum nitride generated in this manner is deposited on the substrate 3 to form a part of the metal nitride film 18.

  Analysis of the tantalum nitride film (metal nitride film 18) formed in this manner revealed that the N / M ratio was 1.

<When the nitrogen gas / halogen gas flow ratio is changed>
Next, the metal nitride film 18 was formed by changing the N ₂ / Cl ₂ gas flow rate ratio. FIG. 11A is a diagram showing the relationship between the N ₂ / Cl ₂ gas flow rate ratio and the N / M ratio of the deposited metal nitride film. As shown in the figure, it can be seen that the N / M ratio of the metal nitride film 18 to be formed can be freely controlled by changing the N ₂ / Cl ₂ gas flow rate ratio. In the figure, GR _{1 on} the horizontal axis is 0.03, GR ₂ is 0.005, and GR ₃ is 0.025. R _{1 on} the vertical axis is 1, R ₂ is 0.05, and R ₃ is 0.95.

That is, by controlling the N ₂ / Cl ₂ gas flow rate ratio within the range of greater than 0 and 0.03 or less, the metal nitride film 18 in which the N / M ratio is freely controlled to be greater than 0 and 1 or less is formed. be able to. In particular, when the N ₂ / Cl ₂ gas flow ratio is in the range of 0.005 or more and 0.025 or less, the relationship between the N ₂ / Cl ₂ gas flow ratio and the N / M ratio is a linear relationship (a relationship that can be expressed by a linear function). By forming a film within this range, it is possible to form a film with improved N / M ratio control accuracy. When the N ₂ / Cl ₂ gas flow rate ratio is in the range of 0.005 or more and 0.025 or less, the metal nitride film 18 in which the N / M ratio is freely controlled to 0.05 or more and 0.95 or less is formed. Can be membrane.

Further, the N ₂ / Cl ₂ gas flow ratio may be controlled in a range larger than 0.03, for example, in a range larger than 0.03 and 0.1 or less, or larger than 0.03 and 0.05 or less. As shown in FIG. 11A, even if the N ₂ / Cl ₂ gas flow rate ratio is made larger than 0.03, the N / M ratio hardly changes. Therefore, the range of 0.03 or more is a range in which a metal nitride film having an N / M ratio of about 1 can be obtained.

In the present embodiment described above, an example in which the metal nitride film 18 having a uniform N / M ratio is formed in the film by maintaining the N ₂ / Cl ₂ gas flow rate ratio constant in the film forming process has been described. However, by changing the N ₂ / Cl ₂ gas flow rate ratio during the film forming process, the metal nitride film 18 with the N / M ratio changed in the film can be formed.

  Such a film formation mode is possible because the metal nitride film formation principle in the present invention supplies a nitrogen component in a gas state, and the N / M ratio is controlled by freely controlling the gas flow rate. This is because it can be changed. On the other hand, for example, in the film forming principle in which the nitrogen radical component is obtained from solid nitride, the amount of nitrogen radicals cannot be freely controlled, resulting in a film forming form with a low degree of freedom.

<Significance of freely controlling the N / M ratio>
FIG. 11B is a diagram showing the relationship between the N / M ratio of the deposited metal nitride film 18 and the work function. In the figure, the horizontal axis represents the N / M ratio of the metal nitride film to be deposited (the ratio is larger toward the right in the figure), and the vertical axis represents the work function of the metal nitride film (the value is larger toward the top in the figure). ). From the figure, it can be seen that the ability to form a metal nitride film having a freely controlled N / M ratio means that a metal nitride film having a freely controlled work function can be formed.

  For example, the gate electrode of a transistor needs to be a thin film whose work function is controlled to a predetermined value depending on the transistor structure and transistor characteristics. At this time, when a metal nitride film is applied to the gate electrode, the transistor can be optimally manufactured regardless of the transistor structure and transistor characteristics as long as the work function can be freely controlled. Therefore, an optimum transistor can be manufactured by applying the metal nitride film formed according to this embodiment.

<Application examples>
In addition, although chlorine gas diluted with helium etc. was mentioned as an example and demonstrated as halogen gas, it is also possible to use chlorine gas independently or to apply hydrochloric acid gas (HCl). When hydrochloric acid gas is applied, hydrochloric acid radicals and hydrogen radicals are generated as gas plasma, but the precursor generated by etching the member to be etched 14 is tantalum chloride gas. Accordingly, the halogen gas may be any gas containing chlorine, and a mixed gas of hydrochloric acid gas and chlorine gas may be used.

<About 2nd thru | or 4th embodiment>
Next, a metal nitride film manufacturing method and a metal nitride film manufacturing apparatus according to second to fourth embodiments of the present invention will be described with reference to FIGS. Also in the metal film production method and metal nitride film production apparatus nitride described below as in the first embodiment, by supplying by controlling the N ₂ / Cl ₂ gas flow rate ratio, N / M on a substrate A metal nitride film having a freely controlled ratio can be formed.

  2 to 4 are schematic internal configuration diagrams of a metal nitride film manufacturing apparatus for performing the metal nitride film manufacturing methods according to the second to fourth embodiments of the present invention, respectively. The same members as those in the metal nitride film manufacturing apparatus shown in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

<Second Embodiment>
In the metal nitride film manufacturing apparatus according to the second embodiment shown in FIG. 2, the upper surface of the chamber 1 is an opening, and the opening is formed of a metal that can form a high vapor pressure halide. It is blocked by. The inside of the chamber 1 closed by the member to be etched 20 is maintained at a predetermined pressure by the vacuum device 8.

  A coiled plasma antenna 21 is provided around the cylindrical portion of the chamber 1, and the matching device 10 and the power source 11 are connected to the plasma antenna 21 to supply a high-frequency current. The plasma antenna 21, the matching unit 10 and the power source 11 constitute a plasma generator which is a plasma generating means.

  In the metal nitride film manufacturing apparatus according to the present embodiment, chlorine gas and nitrogen gas as halogen gases are supplied from the nozzle 12 into the chamber 1 in the film forming process, and electromagnetic waves are incident from the plasma antenna 21 into the chamber 1. Thus, chlorine gas and nitrogen gas are excited to generate chlorine gas plasma and nitrogen gas plasma.

These gas plasmas are generated in the region shown by the gas plasma 16. The etching reaction occurs in the member to be etched 20 by the chlorine gas plasma, and the metal nitride film 18 is formed by the action described in the first embodiment. Also in the second embodiment, the metal nitride film 18 with the N / M ratio freely controlled can be formed by controlling the N ₂ / Cl ₂ gas flow rate ratio within a predetermined range.

<Third Embodiment>
In the metal nitride film manufacturing apparatus according to the third embodiment shown in FIG. 3, the upper surface of the chamber 1 is an opening, and the opening is made of a metal that can form a high vapor pressure halide. It is blocked by. The inside of the chamber 1 closed by the member to be etched 20 is maintained at a predetermined pressure by the vacuum device 8. The matching member 10 and the power source 11 are connected to the member to be etched 20, and a high frequency current is supplied to the member to be etched 20. The support base 2 is grounded by a ground 22.

  In the metal nitride film manufacturing apparatus according to this embodiment, chlorine gas and nitrogen gas as halogen gases are supplied into the chamber 1 from the nozzle 12, and an electric field is applied from the member to be etched 20 to the inside of the chamber 1. Chlorine gas plasma and nitrogen gas plasma are generated by exciting chlorine gas and nitrogen gas.

These gas plasmas are generated in the region shown by the gas plasma 16. The etching reaction occurs in the member to be etched 20 by the chlorine gas plasma, and the metal nitride film 18 is formed by the action described in the first embodiment. Also in the third embodiment, the metal nitride film 18 in which the N / M ratio is freely controlled can be formed by controlling the N ₂ / Cl ₂ gas flow rate ratio within a predetermined range.

  In the metal nitride film manufacturing apparatus according to the present embodiment, the member to be etched 20 itself is used as an electrode for plasma generation, and therefore the plasma antenna 9 (see FIG. 1) is provided above the chamber 1 and around the cylinder portion. The plasma antenna 21 (see FIG. 2) is not necessary, and the degree of freedom of configuration around the apparatus can be increased.

<Fourth Embodiment>
In the metal nitride film manufacturing apparatus according to the fourth embodiment shown in FIG. 4, the upper surface of the chamber 1 is an opening, and the opening is closed by a ceiling plate 7 made of ceramics (made of an insulating material), for example. ing. A member to be etched 30 made of metal capable of forming a high vapor pressure halide is provided on the lower surface of the ceiling plate 7, and the member to be etched 30 has a conical shape.

  A plurality of slit-shaped openings 31 are formed in the side wall of the chamber 1 at substantially the same height as the member 30 to be etched, and one end of a cylindrical passage 32 is fixed to the opening 31. A cylindrical excitation chamber 33 made of an insulator is provided in the middle of the passage 32, and a coiled plasma antenna 34 is provided around the excitation chamber 33. The plasma antenna 34 includes the matching unit 10 and the power source 11. And a high frequency current is supplied.

  Flow rate controllers 35, 36 are connected to the other end side of the passage 32, and chlorine gas as a halogen gas enters the passage 32 via the flow rate controller 35, and nitrogen gas enters the passage 32 via the flow rate controller 36. Is supplied. Hereinafter, a part constituted by the opening 31, the passage 32, the excitation chamber 33, the plasma antenna 34, the matching unit 10, and the power source 11 is referred to as an external plasma generator (external plasma generation means).

  Hereinafter, a mechanism in which the gas plasma acts on the member 30 to be etched will be described. The chlorine gas supplied into the passage 32 via the flow rate controller 35 is sent into the excitation chamber 33. Further, the nitrogen gas supplied into the passage 32 via the flow rate controller 36 is sent into the excitation chamber 33. Next, electromagnetic waves are incident on the inside of the excitation chamber 33 from the plasma antenna 34 to excite chlorine gas and nitrogen gas to generate chlorine gas plasma and nitrogen gas plasma (gas plasma 37).

Since the vacuum device 8 generates a predetermined differential pressure between the pressure inside the chamber 1 and the pressure inside the excitation chamber 33, chlorine radicals and nitrogen radicals in the gas plasma 37 generated in the excitation chamber 33 are opened. It is sent from the part 31 to the member 30 to be etched in the chamber 1. As a result, an etching reaction occurs in the member 30 to be etched due to chlorine radicals, and the metal nitride film 18 is formed by the action described in the first embodiment. Also in the fourth embodiment, the metal nitride film 18 with the N / M ratio freely controlled can be formed by controlling the N ₂ / Cl ₂ gas flow rate ratio within a predetermined range.

  In the metal nitride film manufacturing apparatus according to the present embodiment, the gas plasma 37 is generated in an external plasma generator that is isolated from the chamber 1 (provided outside the main body of the chamber 1). The risk of exposure to plasma can be suppressed, and damage due to plasma can be suppressed.

  For example, when further film formation is performed on the substrate 3 on which a film of another material is already formed, the film of the material already formed is damaged by using the metal nitride film manufacturing apparatus according to this embodiment. The second film formation can be performed without the above. As a means for generating the gas plasma 37 with an external plasma generator, a microwave, a laser, an electron beam, radiated light, or the like can be used.

<Application Examples in the First to Fourth Embodiments>
In the first to fourth embodiments, the function of supplying chlorine gas and the function of supplying nitrogen gas are integrated into one gas supply device (for example, both gases are supplied from the nozzle 12 in FIG. 1). However, the present invention is not limited to this example. For example, a nozzle for supplying chlorine gas and a nozzle for supplying nitrogen gas may be installed separately.

  In this case, in the metal nitride film manufacturing apparatus according to the fourth embodiment, as will be described later, an excitation chamber dedicated to chlorine gas and an excitation chamber dedicated to nitrogen gas are installed (eighth embodiment according to FIG. 8). By separately providing both gas supply devices, supply control of both gases can be performed with high accuracy.

<About Fifth to Eighth Embodiments>
Next, a metal nitride film manufacturing method and a metal nitride film manufacturing apparatus according to fifth to eighth embodiments of the present invention will be described with reference to FIGS. Also in the metal film production method and metal nitride film production apparatus nitride described below as in the first embodiment, by supplying by controlling the N ₂ / Cl ₂ gas flow rate ratio, N / M on a substrate A metal nitride film having a freely controlled ratio can be formed.

  FIG. 5 to FIG. 8 are schematic internal configuration diagrams of a metal nitride film manufacturing apparatus for performing the metal nitride film manufacturing method according to the fifth to eighth embodiments of the present invention, respectively. The same members as those in the metal nitride film manufacturing apparatus shown in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

<Fifth Embodiment>
The metal nitride film manufacturing apparatus according to the fifth embodiment shown in FIG. 5 is an example to which the first embodiment shown in FIG. 1 is applied. Compared with the metal nitride film manufacturing apparatus shown in FIG. 1, in the fifth embodiment, a supply apparatus for supplying nitrogen gas and a supply apparatus for supplying chlorine gas are installed independently. It differs from the point that it can be plasmatized in advance and supplied into the chamber 1 as nitrogen gas plasma 38.

  In this embodiment, the external plasma generator described in the fourth embodiment is dedicated to nitrogen gas, and is installed on the side wall of the chamber 1 at almost the same height as the substrate 3 (second external plasma generating means). ), Before the nitrogen gas is supplied into the chamber 1, the plasma is converted into nitrogen gas plasma 38 and supplied to the upper surface of the substrate 3. Chlorine gas is supplied from the nozzle 12 to the inside of the chamber 1 separately from the nitrogen gas plasma 38 and is converted into plasma by the action of electromagnetic waves incident from the plasma antenna 9.

<Sixth Embodiment>
The metal nitride film manufacturing apparatus according to the sixth embodiment shown in FIG. 6 is an example to which the second embodiment shown in FIG. 2 is applied. Compared with the metal nitride film manufacturing apparatus shown in FIG. 2, in the sixth embodiment, the supply device for supplying nitrogen gas and the supply device for supplying chlorine gas are installed independently, It differs from the point that it can be plasmatized in advance and supplied into the chamber 1 as nitrogen gas plasma 38.

  In this embodiment, the external plasma generator described in the fourth embodiment is dedicated to nitrogen gas, and is installed on the side wall of the chamber 1 at almost the same height as the substrate 3 (second external plasma generating means). ), Before the nitrogen gas is supplied into the chamber 1, the plasma is converted into nitrogen gas plasma 38 and supplied to the upper surface of the substrate 3. Chlorine gas is supplied from the nozzle 12 to the inside of the chamber 1 separately from the nitrogen gas plasma 38, and is converted into plasma by the action of electromagnetic waves incident from the plasma antenna 21.

<Seventh Embodiment>
The metal nitride film manufacturing apparatus according to the seventh embodiment shown in FIG. 7 is an example to which the third embodiment shown in FIG. 3 is applied. Compared with the metal nitride film manufacturing apparatus shown in FIG. 3, in the seventh embodiment, the supply device for supplying nitrogen gas and the supply device for supplying chlorine gas are installed independently, It differs from the point that it can be plasmatized in advance and supplied into the chamber 1 as nitrogen gas plasma 38.

  In this embodiment, the external plasma generator described in the fourth embodiment is dedicated to nitrogen gas, and is installed on the side wall of the chamber 1 at almost the same height as the substrate 3 (second external plasma generating means). ), Before the nitrogen gas is supplied into the chamber 1, the plasma is converted into nitrogen gas plasma 38 and supplied to the upper surface of the substrate 3. Chlorine gas is supplied from the nozzle 12 into the chamber 1 separately from the nitrogen gas plasma 38, and is converted into plasma by the action of an electric field generated between the member to be etched 20 and the support 2.

<Eighth Embodiment>
The metal nitride film manufacturing apparatus according to the eighth embodiment shown in FIG. 8 is an example to which the fourth embodiment shown in FIG. 4 is applied. Compared with the metal nitride film manufacturing apparatus shown in FIG. 4, the eighth embodiment is different in that a supply device for supplying nitrogen gas and a supply device for supplying chlorine gas are independently installed.

  In this embodiment, an external plasma generator dedicated to chlorine gas is installed on the side wall of the chamber 1 at almost the same height as the member 30 to be etched, and an external plasma generator dedicated to nitrogen gas (second external plasma generation) Means) is installed on the side wall of the chamber 1 at substantially the same height as the substrate 3.

  That is, as an external plasma generator dedicated to nitrogen gas, a plurality of slit-shaped openings 31 ′ are formed in the side wall of the chamber 1 at substantially the same height as the substrate 3, and a cylindrical passage is formed in the openings 31 ′. One end of each 32 'is fixed, and a cylindrical excitation chamber 33' made of an insulator is provided in the middle of the passage 32 '. A coiled plasma antenna 34' is provided around the excitation chamber 33 '. The plasma antenna 34 ′ is connected to the matching unit 10 ′ and the power source 11 ′ so that a high-frequency current is supplied. A flow rate controller 36 is connected to the other end of the passage 32 ′, and nitrogen gas is supplied into the passage 32 ′ through the flow rate controller 36.

  As a result, the chlorine gas is converted into plasma in the excitation chamber 33, the chlorine gas plasma 39 is supplied toward the member 30 to be etched, and the nitrogen gas is converted into plasma in the excitation chamber 33 ′ separately from the chlorine gas. Is supplied to the upper surface of the substrate 3.

<Special Effects According to Fifth to Eighth Embodiments>
The film forming mechanism of the metal nitride film 18 in the fifth to eighth embodiments is basically the same as the film forming mechanism described in the first to fourth embodiments. However, in the fifth to eighth embodiments, nitrogen gas is supplied to the upper surface of the substrate 3 as nitrogen gas plasma 38 from an external plasma generator (second external plasma generating means) installed at substantially the same height as the substrate 3. By doing so, it is considered that the fear of passivation of the members 14, 20, 30 to be etched by nitrogen radicals can be eliminated. Therefore, in the fifth to eighth embodiments, the metal nitride film 18 in which the N / M ratio is more accurately controlled is formed by controlling the N ₂ / Cl ₂ gas flow rate ratio within a predetermined range. Can do.

  Further, by adopting a configuration in which nitrogen gas plasma is supplied to the upper surface of the substrate 3, a nitridation reaction of tantalum chloride as the precursor 17, particularly a nitridation reaction of tantalum alone formed on the substrate 3 generated near the substrate 3. It is considered that the rate of occurrence of the nitridation reaction of tantalum chloride adsorbed on the substrate 3 (the above equation (8)) (the above equation (9)) is increased. Therefore, it is advantageous when it is desired to efficiently form a metal nitride film having a relatively high N / M ratio.

<Ninth Embodiment: Example in which chamber is separated into two chambers>
The inside of the chamber is partitioned into two upper and lower chambers by a member to be etched made of tantalum (Ta). A chlorine gas, which is a halogen, is supplied to one chamber where no substrate exists and inductive plasma is generated to generate chlorine gas plasma to generate chlorine radicals (Cl ^* ). By etching the member to be etched with chlorine radicals, a precursor composed of a tantalum component and a chlorine component (tantalum chloride gas) is generated and supplied into the other chamber from an ejection hole provided in the member to be etched.

Nitrogen gas is supplied into the other chamber and induction plasma is generated to generate nitrogen gas plasma to generate nitrogen radicals (N ^* ). By making the temperature on the substrate side lower than the temperature of the member to be etched, the precursor is reduced with chlorine radicals to produce a tantalum component, and the metal nitride produced by nitriding the tantalum component with nitrogen radicals is used as the surface of the substrate. To be adsorbed (deposited).

  As a result, the tantalum nitride thin film can be produced by controlling the ratio of the tantalum component and the nitrogen component constituting the metal nitride to a desired state. Further, since chlorine gas plasma is generated in one chamber, the influence of the plasma on the substrate can be suppressed to a minimum.

  Therefore, when a tantalum nitride thin film is applied as a gate electrode film of a transistor, an electrode thin film having a desired work function can be obtained. Further, when a tantalum nitride thin film is applied to the barrier metal film, it is possible to obtain a thin film in which the adhesion and diffusion resistance of the wiring metal are optimally controlled. Accordingly, a thin film manufacturing apparatus and a thin film manufacturing method capable of manufacturing a thin film capable of controlling the film quality are obtained. The member to be etched is not limited to tantalum (Ta), as in the first embodiment, and other metals such as copper can be applied.

  The ninth embodiment will be described in detail with reference to the drawings. FIG. 12 is a schematic internal configuration diagram of a metal nitride film production apparatus for performing the metal nitride film production method according to the ninth embodiment of the present invention. As shown in the figure, a support base 2 is provided in the vicinity of the bottom of a cylindrical chamber 1, and a substrate 3 is placed on the support base 2.

  The support table 2 is provided with a temperature controller 6 including a heater 4 and a refrigerant flow path 5. The support table 2 has a predetermined temperature (for example, a temperature at which the substrate 3 is maintained at 100 ° C. to 300 ° C.) by the temperature controller 6. ) Is controlled. The shape of the chamber is not limited to a cylindrical shape, and for example, a rectangular chamber can be applied.

  The upper surface of the chamber 1 is an opening, and the opening is closed by a plate-like ceiling plate 7 made of an insulating material (for example, made of ceramics). The chamber 1 is partitioned into two chambers, an upper chamber 42 and a lower chamber 43, by a partition plate 41 as an etching member made of tantalum (Ta), and a plurality of ejection holes 44 are formed in the partition plate 41. . Thereby, the upper chamber 42 constitutes one chamber where the substrate 3 does not exist, and the lower chamber 43 constitutes the other chamber where the substrate 3 exists.

  A plasma antenna 9 for converting the inside of the upper chamber 42 into plasma is provided above the ceiling plate 7, and the plasma antenna 9 is formed in a planar ring shape parallel to the surface of the ceiling plate 7. A matching unit 10 and a power source 11 are connected to the plasma antenna 9 to supply a high frequency. Plasma generating means for generating induction plasma is constituted by the plasma antenna 9, the matching unit 10 and the power source 11.

  Further, a coiled plasma antenna 45 is provided around the chamber 1 of the lower chamber 43 to convert the inside of the lower chamber 43 into plasma. The matching device 10 and the power source 11 are connected to the plasma antenna 45 so that a high frequency is generated. Supplied. Plasma generating means for generating induction plasma is constituted by the plasma antenna 45, the matching unit 10 and the power source 11. If the plasma antenna 9 can generate induction plasma in the lower chamber 43, the plasma antenna 45, the matching unit 10 connected to the antenna 45, and the power source 11 can be omitted.

  Around the cylindrical portion of the upper chamber 42 of the chamber 1, there are a plurality of nozzles 12 for supplying chlorine gas as halogen into the upper chamber 42 at equal intervals in the circumferential direction (for example, eight locations: two locations are shown in the figure). Is connected). Chlorine gas is sent to the nozzle 12 via a flow rate controller 35 whose flow rate and pressure are controlled.

  A plurality of nozzles 46 for supplying nitrogen gas into the lower chamber 43 of the chamber 1 are connected at equal intervals in the circumferential direction (for example, eight locations: two locations are shown in the figure). Nitrogen gas is sent to the nozzle 46 via a flow rate controller 47 whose flow rate and pressure are controlled.

  The flow rate and pressure of the flow rate controller 35 are sent to the controller 50, and the flow rate and pressure of the nitrogen gas sent to the nozzle 46 are controlled by a command from the controller 50 via the flow rate controller 47. That is, the flow rate and pressure of nitrogen gas are controlled according to the flow rate and pressure of chlorine gas, and the supply balance of chlorine gas and nitrogen gas is controlled by the controller 50. Note that the flow rate and pressure of chlorine gas can be controlled in accordance with the flow rate and pressure of nitrogen gas.

  Gases that are not involved in film formation are exhausted from the exhaust port 15. The inside of the chamber 1 closed by the ceiling plate 7 is maintained at a predetermined pressure by the vacuum device 8. Note that fluorine, bromine, iodine, or the like can be used as the halogen gas. Since the thin film production apparatus according to this embodiment generates chlorine gas plasma in the upper chamber 42 where the substrate 3 does not exist, the influence of the chlorine gas plasma on the substrate 3 can be suppressed to a minimum. Further, since the plasma generating means is provided corresponding to the upper chamber 42 and the lower chamber 43, the plasma generation state can be controlled individually in the upper chamber 42 and the lower chamber 43.

In each of the above-described embodiments, the example in which the metal nitride film 18 having a uniform N / M ratio is formed in the film by maintaining the N ₂ / Cl ₂ gas flow rate ratio constant in the film forming process has been described. However, by changing the N ₂ / Cl ₂ gas flow rate ratio during the film forming process, the metal nitride film 18 with the N / M ratio changed in the film can be formed.

  Such a film formation mode is possible because the metal nitride film formation principle in the present invention supplies a nitrogen component in a gas state, and the N / M ratio is controlled by freely controlling the gas flow rate. This is because it can be changed. On the other hand, for example, in the film forming principle in which the nitrogen radical component is obtained from solid nitride, the amount of nitrogen radicals cannot be freely controlled, resulting in a film forming form with a low degree of freedom. Hereinafter, an example in which the N / M ratio is changed in the film will be described with reference to FIGS.

FIG. 13 is a diagram illustrating an example in which the supply of chlorine gas and nitrogen gas is alternately performed when a thin film having an N / M ratio changed therein is manufactured. The example shown in FIG. 13 is an example in which supply of chlorine gas and nitrogen gas is performed alternately, film formation of precursor metal components (deposition of Ta by reduction with chlorine radical Cl ^* ) and nitrogen radicals. Nitriding is performed alternately.

  That is, as shown in FIG. 13, preheating is performed by supplying He gas as a rare gas and generating plasma. Under the control of the controller 50, only the chlorine gas is supplied and the supply of the nitrogen gas is stopped between the film formation start time t1 and the time t2. Between time t2 and time t3, the supply of chlorine gas is stopped and only nitrogen gas is supplied. From time t3 to time t4, only the chlorine gas is supplied again, the supply of nitrogen gas is stopped, and the supply of chlorine gas and nitrogen gas is alternately performed at time t5, time t6.

By alternately supplying chlorine gas and nitrogen gas, the time during which only chlorine gas is supplied is the film formation of the precursor metal component (deposition of Ta by reduction with chlorine radical Cl ^* ) and nitridation by nitrogen radicals. Are alternately performed to obtain a thin film in which a tantalum component and a nitrided tantalum nitride component are stacked. This facilitates control of the film thickness of the tantalum nitride thin film.

  Next, FIG. 14 is a diagram illustrating an example in which the supply of nitrogen gas is gradually decreased with respect to chlorine gas when a thin film having an N / M ratio changed therein is manufactured. The example shown in FIG. 14 is an example in which the supply of nitrogen gas is gradually decreased with respect to chlorine gas, and the ratio of the tantalum component and the nitrogen component is changed in the film thickness direction (the film with nitridation gradually decreased). (The ratio changes in the thickness direction) is continuously formed.

  That is, as shown in FIG. 14, preheating is performed by supplying He gas as a rare gas to generate plasma. At the time t1 when film formation is started, chlorine gas and nitrogen gas whose flow rate and pressure are relatively controlled by the controller 50 are supplied, and the supply of nitrogen gas is gradually reduced as time passes.

By gradually reducing the supply of nitrogen gas, the metal nitride formed by nitriding the tantalum component of the precursor 17 with nitrogen radicals is adsorbed (deposited) on the substrate 3 side immediately after the start of film formation. The components are reduced to finally form a metal component film of the precursor (deposition of Ta by reduction with chlorine radical Cl ^* ). That is, a film in which the ratio of the tantalum component and the nitrogen component is changed in the film thickness direction is continuously formed. Therefore, a tantalum nitride thin film in which the stress is relaxed can be obtained.

Next, FIG. 15 is a diagram showing an example in which the supply of nitrogen gas is stopped after supplying chlorine gas and nitrogen gas when a thin film having an N / M ratio changed therein is manufactured. It is. The example shown in FIG. 15 is an example in which supply of nitrogen gas is stopped after supply of chlorine gas and nitrogen gas, and the metal component of the precursor (deposition of Ta by reduction with chlorine radical Cl ^* ). After forming Ta _x N _(1-x) (1> x) formed by nitriding with nitrogen radicals, a tantalum component is formed.

  That is, as shown in FIG. 15, preheating is performed by supplying He gas as a rare gas and generating plasma. At the time of film formation start t1, chlorine gas and nitrogen gas whose flow rate and pressure are relatively controlled by the controller 50 are supplied, and supply of nitrogen gas is stopped at a time ta after a predetermined time.

  By stopping the supply of nitrogen gas at time ta, metal nitride formed by nitriding the tantalum component of precursor 17 (TaCl) with nitrogen radicals is adsorbed (deposited) on the substrate 3 side until time ta. After ta, only the tantalum component of the precursor 17 (TaCl) is adsorbed (deposited). Therefore, a tantalum nitride thin film having a tantalum film as a surface layer can be obtained with simple control.

<Tenth Embodiment: Example of Lifting Control of Supporting Base>
The chamber provided with the member to be etched made of tantalum (Ta) is divided into an up and down state by controlling the support on which the substrate is placed. That is, when the support is raised, chlorine gas is supplied and induction plasma is generated, and chlorine gas plasma is generated to generate chlorine radicals (Cl ^* ). By etching the member to be etched with chlorine radicals, a precursor (tantalum chloride gas) composed of a tantalum component and a chlorine component is generated.

On the other hand, when the support is lowered, nitrogen gas is supplied and induction plasma is generated to generate nitrogen gas plasma to generate nitrogen radicals (N ^* ). By making the temperature on the substrate side lower than the temperature of the member to be etched, the precursor is reduced with chlorine radicals to produce a tantalum component, and the metal nitride produced by nitriding the tantalum component with nitrogen radicals is used as the surface of the substrate. To be adsorbed (deposited).

  As a result, the tantalum nitride thin film can be produced by controlling the ratio of the tantalum component and the nitrogen component constituting the metal nitride to a desired state. Also, by raising and lowering the support base, the state in the chamber is changed to a state in which chlorine gas plasma is generated and a state in which chlorine gas plasma and nitrogen gas plasma or nitrogen gas plasma is generated, and chlorine radicals and nitrogen radicals are changed. It can be generated accurately.

  Therefore, when a tantalum nitride thin film is applied as a gate electrode film of a transistor, an electrode thin film having a desired work function can be obtained. Further, when a tantalum nitride thin film is applied to the barrier metal film, it is possible to obtain a thin film in which the adhesion and diffusion resistance of the wiring metal are optimally controlled. The member to be etched is not limited to tantalum (Ta) as in the first embodiment, and other metals such as copper can be applied.

  The tenth embodiment will be described in detail with reference to the drawings. 16 and 17 are schematic internal configuration diagrams of a metal nitride film production apparatus for performing the metal nitride film production method according to the tenth embodiment of the present invention. As shown in these drawings, a support base 61 is provided in the vicinity of the bottom portion of the chamber 1 formed in a cylindrical shape so as to be movable up and down, and the substrate 3 is placed on the support base 61.

  The support base 61 is provided with a temperature controller 6 including the heater 4 and the refrigerant flow path 5, and the support base 61 has a predetermined temperature (for example, a temperature at which the substrate 3 is maintained at 100 ° C. to 300 ° C.) by the temperature controller 6. ) Is controlled. The shape of the chamber is not limited to a cylindrical shape, and for example, a rectangular chamber can be applied.

  An elevating support column 62 is attached to the lower portion of the support base 61, and the elevating support column 62 is accommodated in an elevating chamber 63 provided integrally with the lower portion of the chamber 1. The elevating chamber 63 is provided with an elevating driver 64 for elevating and lowering the elevating support column 62, and the elevating support column 62 is driven up and down by the elevating driver 64. By raising and lowering the elevating support column 62, the support base 61 moves up and down in the chamber 1 so that the inside of the chamber 1 is divided into an upper and lower state.

  The upper surface of the chamber 1 is an opening, and the opening is closed by a plate-like ceiling plate 7 made of an insulating material (for example, made of ceramics). A plasma antenna 9 for converting the inside of the chamber 1 into plasma is provided above the ceiling plate 7, and the plasma antenna 9 is formed in a planar ring shape parallel to the surface of the ceiling plate 7. A matching unit 10 and a power source 11 are connected to the plasma antenna 9 to supply a high frequency. Plasma generating means for generating induction plasma is constituted by the plasma antenna 9, the matching unit 10 and the power source 11.

  The chamber 1 holds a member to be etched 14 made of tantalum (Ta) as a metal, and the member to be etched 14 is disposed in a discontinuous state between the substrate 3 and the ceiling plate 7 with respect to the electric flow of the plasma antenna 9. Has been. For example, the member to be etched 14 includes a rod member 14 b and a ring member 14 a, and the rod member 14 b is provided on the ring member 14 a so as to extend toward the center side of the chamber 1.

  Thus, the member 14 to be etched is structurally discontinuous with respect to the circumferential direction, which is the direction of electricity flow of the plasma antenna 9. In addition, as a structure which makes it a discontinuous state with respect to the electric flow of the plasma antenna 9, it is also possible to form a to-be-etched member in a grid | lattice form, or a mesh shape.

  Around the cylindrical portion of the chamber 1 above the member 14 to be etched, there are a plurality of nozzles 12 for supplying chlorine gas as halogen into the chamber 1 at equal intervals in the circumferential direction (for example, eight locations: two locations in the figure). Connected) Chlorine gas is sent to the nozzle 12 via a flow rate controller 13 whose flow rate and pressure are controlled.

  Nozzles 46 for supplying nitrogen gas into the chamber 1 are arranged at equal intervals in the circumferential direction around the cylindrical portion of the chamber 1 above the support base 61 in a state where the support base 61 is lowered (state of FIG. 16). A plurality of connections (for example, 8 locations: 2 locations are shown in the figure) are connected. Nitrogen gas is sent to the nozzle 46 via a flow rate controller 47 whose flow rate and pressure are controlled.

  The flow rate and pressure of the flow rate controller 13 are sent to the controller 50, and the flow rate and pressure of the nitrogen gas sent to the nozzle 46 are controlled by a command from the controller 50 via the flow rate controller 47. That is, the flow rate and pressure of nitrogen gas are controlled according to the flow rate and pressure of chlorine gas, and the supply balance of chlorine gas and nitrogen gas is controlled by the controller 50. Further, the lift driver 64 is driven by a command from the controller 50. Note that the flow rate and pressure of chlorine gas can be controlled in accordance with the flow rate and pressure of nitrogen gas.

FIG. 18 is a diagram showing the relationship between the lifted state of the support base and the supply control of Cl ₂ gas and N ₂ gas when performing the metal nitride film manufacturing method according to the tenth embodiment of the present invention. As shown in the figure, preheating is performed by supplying He gas as a rare gas to generate plasma. Under the control of the controller 50, the support base 61 is raised and only the chlorine gas is supplied from the start of film formation t1 to the time t2, and the supply of nitrogen gas is stopped. From time t2 to time t3, the support 61 is lowered and the supply of chlorine gas is stopped, and only nitrogen gas is supplied. From time t3 to time t4, the support base 61 is raised again and only chlorine gas is supplied to stop supply of nitrogen gas, and supply of chlorine gas and nitrogen gas is performed at time t5, time t6. And the raising / lowering of the support stand 61 is implemented alternately.

  Gases that are not involved in film formation are exhausted from the exhaust port 15. The inside of the chamber 1 closed by the ceiling plate 7 is maintained at a predetermined pressure by the vacuum device 8. It is also possible to divide the inside of the chamber 1 into an airtight state vertically by the support table 61. In this case, the upper and lower parts are respectively maintained at a predetermined pressure by the vacuum device with the support table 61 interposed therebetween. Note that fluorine, bromine, iodine, or the like can be used as the halogen. By using chlorine as the halogen, a thin film can be manufactured using inexpensive chlorine gas.

<Other application examples>
In each of the above-described embodiments, an example in which a metal nitride film is formed has been described. However, various metal films can be formed by applying oxygen and carbon instead of nitrogen. When oxygen and carbon are applied, the means for generating plasma is not limited to means for generating induction plasma, and capacitively coupled plasma using parallel plates can also be applied.

  When oxygen is applied, oxygen gas or water vapor can be supplied. By using an oxide to which oxygen is applied, a metal oxide is produced and a thin film with a controlled oxygen / metal ratio is obtained. This thin film can be used as a gate electrode, a dielectric for capacitance, a catalyst (for example, titania which is a photocatalyst), an adhesion layer, and the like.

  When carbon is applied, carbon gas or methane gas can be supplied. In this case, the chlorine gas for etching can be reduced or omitted if a compound of chlorine and carbon can be supplied. By using a carbide to which carbon is applied, a metal carbide is produced, and a thin film with a controlled carbon / metal ratio is obtained. This thin film can be used as a protective film, an etching stop film, or the like.

1 is a schematic internal configuration diagram of a metal nitride film manufacturing apparatus for performing a metal nitride film manufacturing method according to a first embodiment of the present invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which implements the metal nitride film preparation method concerning the 2nd Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method concerning the 3rd Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method which concerns on the 4th Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which implements the metal nitride film preparation method concerning the 5th Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which implements the metal nitride film preparation method concerning the 6th Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method concerning the 7th Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which implements the metal nitride film preparation method concerning the 8th Embodiment of this invention. It is a schematic plane structure figure of the member to be etched used for the metal nitride film preparation device concerning a 1st embodiment of the present invention. It is a figure which shows an example of the control method of each gas flow rate at the time of enforcing the metal nitride film preparation method concerning the 1st Embodiment of this invention. FIG. 6A is a diagram showing the relationship between the N ₂ / Cl ₂ gas flow rate ratio when the metal nitride film manufacturing method according to the first embodiment of the present invention is performed and the N / M ratio of the metal nitride film manufactured by the method. FIG. 5B is a diagram showing the relationship between the N / M ratio of the metal nitride film and the work function. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method concerning the 9th Embodiment of this invention. When a thin film with varying N / M ratio in the interior, is a diagram illustrating an example of control was to perform the supply of Cl ₂ gas and N ₂ gas alternately. When a thin film with varying N / M ratio in the interior, is a diagram illustrating an example of control were as supplied the N ₂ gas is gradually reduced with respect to the Cl ₂ gas. When a thin film with varying N / M ratio in the interior, is a diagram illustrating an example of control it was to stop the supply of the N ₂ gas after the supply of Cl ₂ gas and N ₂ gas. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method concerning the 10th Embodiment of this invention. It is a schematic internal block diagram of the metal nitride film preparation apparatus which enforces the metal nitride film preparation method concerning the 10th Embodiment of this invention. In carrying out the tenth nitride metal film production method according to the embodiment of the present invention, it is a diagram showing the relationship between the supply control of the support of the lifting state and Cl ₂ gas and N ₂ gas.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chamber 2 Support stand 3 Board | substrate 4 Heater 5 Refrigerant flow path 6 Temperature controller 7 Ceiling board 8 Vacuum apparatus 9 Plasma antenna 10 Matching device 11 Power supply 12 Nozzle 13 Flow controller 14 Etched member 14a Ring member 14b Bar member 14c Space 15 Exhaust port 16 Gas plasma 17 Precursor 18 Metal nitride film 20 Member to be etched 21 Plasma antenna 22 Ground 30 Member to be etched 31, 31 ′ Opening 32, 32 ′ Passage 33, 33 ′ Excitation chamber 34, 34 ′ Plasma antenna 35, 36 Flow controller 37 Gas plasma 38 Nitrogen gas plasma 39 Chlorine gas plasma 41 Partition plate 42 Upper chamber 43 Lower chamber 44 Ejection hole 45 Plasma antenna 46 Nozzle 47 Flow controller 48 Gas plasma 49 Gas plasma 50 Controller 61 Support base 62 Elevation Support pillar 63 Lifting chamber 64 Lifting drive

Claims (36)

A chamber in which the substrate is accommodated, a support base on which the substrate is placed,
A member to be etched formed of a metal capable of generating a high vapor pressure halide and provided at a position facing the substrate;
Halogen gas supply means for supplying halogen gas to the chamber;
Nitrogen gas supply means for supplying nitrogen gas to the chamber;
Plasma generating means for generating halogen gas plasma and nitrogen gas plasma by converting the halogen gas and nitrogen gas into plasma;
Temperature control means for lowering the temperature of the substrate lower than the temperature of the member to be etched,
The member to be etched is etched with the halogen gas plasma to generate a precursor made of a metal halide, and the metal component is nitrided with the nitrogen gas plasma when the metal component of the precursor is formed on the substrate. In the metal nitride film manufacturing apparatus for forming a metal nitride film on the substrate,
Gas supply amount control means for controlling the supply amount of the nitrogen gas is provided so that an N / M ratio, which is an atomic composition ratio between nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value. Metal nitride film production equipment. In the metal nitride film manufacturing apparatus according to claim 1,
The upper surface of the chamber is sealed with an insulating member,
The plasma generating means comprises a planar coil disposed outside the insulating member and a power supply unit for supplying power to the coil.
The metal nitride film manufacturing apparatus, wherein the member to be etched is disposed between the substrate and the insulating member, and is formed in a shape that allows the precursor to be supplied to the substrate. In the metal nitride film manufacturing apparatus according to claim 1,
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means comprises a coil wound around the chamber and a power supply for supplying power to the coil. In the metal nitride film manufacturing apparatus according to claim 1,
The support is grounded;
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes the member to be etched, a power supply unit that supplies power to the member to be etched, and the grounded support base, and generates gas plasma between the member to be etched and the support base. An apparatus for producing a metal nitride film. In the metal nitride film manufacturing apparatus according to claim 1,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas supply means is provided in the upper chamber,
The nitrogen gas supply means is provided in the lower chamber,
The plasma generating means is provided in the upper chamber and the lower chamber, respectively. In the metal nitride film manufacturing apparatus according to claim 1,
An apparatus for producing a metal nitride film, comprising elevating drive means for elevating the support base in the chamber. In the metal nitride film manufacturing apparatus according to claim 1,
The plasma generation means is configured as an external plasma generation means outside the chamber body, and the halogen gas supply means and the nitrogen gas supply means supply the halogen gas and the nitrogen gas to the external plasma generation means. ,
The metal nitride film manufacturing apparatus according to claim 1, wherein the halogen gas plasma and the nitrogen gas plasma are preliminarily converted into plasma outside the chamber main body by the external plasma generating means and supplied to the vicinity of the member to be etched. In the metal nitride film manufacturing apparatus according to claim 1,
The upper surface of the chamber is sealed by the member to be etched,
The plasma generating means includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil, and is an external plasma installed outside the chamber body. Configured as a generating means,
The halogen gas supply means supplies halogen gas to the cylindrical passage,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The halogen gas plasma and the nitrogen gas plasma are plasmas that are preliminarily converted into plasma outside the chamber body by the external plasma generating means and are supplied to the vicinity of the member to be etched. Production device. The metal nitride film manufacturing apparatus according to any one of claims 1 to 8,
A second external plasma generation unit provided on a side wall of the chamber at substantially the same height as the substrate; the nitrogen gas supply unit supplies the nitrogen gas to the second external plasma generation unit;
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generating means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber. Metal film production equipment. The metal nitride film manufacturing apparatus according to any one of claims 1 to 8,
A first passage is provided on a side wall of the chamber at substantially the same height as the substrate, and includes a cylindrical passage communicating with the chamber, a coil wound around the cylindrical passage, and a power supply unit that supplies power to the coil. Two external plasma generating means,
The nitrogen gas supply means supplies nitrogen gas to the cylindrical passage,
The nitrogen gas plasma is plasma that has been converted into plasma by the second external plasma generating means in advance outside the chamber body and supplied to the upper surface of the substrate inside the chamber. Metal film production equipment. The metal nitride film manufacturing apparatus according to any one of claims 1 to 10,
The N / M ratio is greater than 0 and 1 or less. The metal nitride film manufacturing apparatus according to claim 1,
The supply amount of nitrogen gas controlled by the gas supply amount control means is such that a nitrogen gas / halogen gas flow rate ratio, which is a ratio to the supply amount of the halogen gas, is greater than 0 and less than or equal to 0.1. Metal nitride film production equipment. The metal nitride film manufacturing apparatus according to any one of claims 1 to 12,
The gas supply amount control means has a function of changing a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the supply amount of the nitrogen gas and the supply amount of the halogen gas, during the film forming step,
The metal nitride film forming apparatus, wherein the metal nitride film formed on the substrate is a metal nitride film having an N / M ratio changed inside the film. The metal nitride film manufacturing apparatus according to any one of claims 1 to 13,
The metal nitride film forming apparatus, wherein the metal capable of generating the high vapor pressure halide is any one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium, and hafnium. The metal nitride film manufacturing apparatus according to any one of claims 1 to 14,
The metal nitride film manufacturing apparatus, wherein the halogen gas is chlorine gas. The metal nitride film manufacturing apparatus according to any one of claims 1 to 15,
Instead of the nitrogen gas supply means for supplying the nitrogen gas, an oxygen supply means or a carbon supply means for supplying oxygen or carbon is provided, and an oxidation or metal carbide film is formed on the substrate. Metal carbide film production equipment. Place the substrate on the support and place it in the chamber,
A precursor made of a metal halide formed of a metal capable of generating a high vapor pressure halide and etched with a halogen gas plasma obtained by plasmaizing a halogen gas into a member to be etched provided at a position facing the substrate. Produces
When the temperature of the substrate is made lower than the temperature of the member to be etched and the metal component of the precursor is formed on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting nitrogen gas into plasma. In the metal nitride film manufacturing method of forming a metal nitride film on the substrate,
A method for producing a metal nitride film, wherein the supply amount of the nitrogen gas is controlled so that an N / M ratio, which is an atomic composition ratio between nitrogen atoms and metal atoms of the metal nitride film, becomes a predetermined value. The method for producing a metal nitride film according to claim 17,
The halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by electromagnetic waves from a planar coil disposed outside the insulating member that seals the upper surface of the chamber.
The metal nitride film manufacturing method, wherein the member to be etched is disposed between the substrate and the insulating member, and is formed into a shape that allows the precursor to be supplied to the substrate. The method for producing a metal nitride film according to claim 17,
The chamber has an upper surface sealed by the member to be etched,
The method for producing a metal nitride film, wherein the halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma using electromagnetic waves from a coil wound around the chamber. The method for producing a metal nitride film according to claim 17,
The support is grounded;
The chamber has an upper surface sealed by the member to be etched,
The method of producing a metal nitride film, wherein the halogen gas plasma and the nitrogen gas plasma are obtained by converting the halogen gas and the nitrogen gas into plasma by an electric field generated between the member to be etched and the support base. . The method for producing a metal nitride film according to claim 17,
The member to be etched is provided to partition the chamber into upper and lower chambers and has a hole communicating from the upper chamber to the lower chamber,
The halogen gas plasma is generated in the upper chamber,
The method of producing a metal nitride film, wherein the nitrogen gas plasma is generated in the lower chamber. The method for producing a metal nitride film according to claim 17,
A metal nitride film manufacturing method comprising forming a film while raising and lowering the support base in the chamber. The method for producing a metal nitride film according to claim 17,
The method for producing a metal nitride film, wherein the halogen gas plasma and the nitrogen gas plasma are previously converted into plasma outside the chamber body and supplied to the vicinity of the member to be etched. The method for producing a metal nitride film according to claim 17,
The chamber has an upper surface sealed by the member to be etched,
The halogen gas plasma and the nitrogen gas plasma are converted into plasma by halogen gas and nitrogen gas supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. A method for producing a metal nitride film, characterized in that the plasma is plasmanized outside the chamber in advance and supplied to the vicinity of the member to be etched. 25. The method for producing a metal nitride film according to claim 17, wherein:
The method of producing a metal nitride film, wherein the nitrogen gas plasma is plasma that has been converted into plasma outside the chamber body and supplied to the upper surface of the substrate inside the chamber. 25. The method for producing a metal nitride film according to claim 17, wherein:
The nitrogen gas plasma is provided on the side wall of the chamber at substantially the same height as the substrate, and is supplied to the inside of the passage by electromagnetic waves from a coil wound around a cylindrical passage communicating with the chamber. A method for producing a metal nitride film, characterized in that the nitrogen gas is plasmatized in advance outside the chamber and supplied to the upper surface of the substrate inside the chamber. 27. The method for producing a metal nitride film according to claim 17,
The method of manufacturing a metal nitride film, wherein the N / M ratio is greater than 0 and 1 or less. The metal nitride film manufacturing method according to any one of claims 17 to 27,
The method for producing a metal nitride film, wherein the supply amount of the nitrogen gas is such that a nitrogen gas / halogen gas flow rate ratio, which is a ratio to the supply amount of the halogen gas, is greater than 0 and 0.1 or less. The metal nitride film manufacturing method according to any one of claims 17 to 28,
During the film forming process, a nitrogen gas / halogen gas flow rate ratio, which is a ratio between the nitrogen gas supply amount and the halogen gas supply amount, is changed to obtain a metal nitride film in which the N / M ratio is changed inside the film. A metal nitride film manufacturing method characterized by forming a film. The metal nitride film manufacturing method according to any one of claims 17 to 29,
The metal nitride film manufacturing method, wherein the metal capable of generating the high vapor pressure halide is any one of tantalum, titanium, tungsten, molybdenum, vanadium, niobium, zirconium, and hafnium. The method for producing a metal nitride film according to any one of claims 17 to 30,
The metal nitride film manufacturing method, wherein the halogen gas is chlorine gas. 32. The method for producing a metal nitride film according to claim 17,
A method for producing an oxidized or metal carbide film, comprising supplying oxygen or carbon instead of the nitrogen gas and forming an oxidized or metal carbide film on the substrate.   A metal nitride film in which the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, is controlled.   A metal nitride film in which the N / M ratio, which is the atomic composition ratio of nitrogen atoms and metal atoms, is controlled to be greater than 0 and 1 or less. The metal nitride film according to claim 33 or 34,
A metal nitride film characterized in that the N / M ratio is changed inside the film. A member to be etched formed of a metal capable of generating a high vapor pressure halide is etched with halogen gas plasma to generate a precursor made of a metal halide,
When forming the metal component of the precursor on the substrate, the metal component is nitrided by nitrogen gas plasma obtained by converting nitrogen gas with a controlled supply amount into plasma, and the substrate is formed on the substrate. 36. The metal nitride film according to claim 33.

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