JP2010029870A - Joining method and joined body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method which can efficiently produce a joined body firmly joined with high dimensional precision at low temperature, and to provide a joined body which is formed by the joining method. <P>SOLUTION: The joining method includes: a stage where a first joining film 31 containing first metal atoms and leaving groups is formed on a first base material 21, so as to obtain a first joining film-fitted base material 11, and further, a second joining film 32 containing second metal atoms having a melting point lower than that of the first metal atoms and leaving groups is formed on a second base material 22, so as to obtain a second joining film-fitted base material 12; a stage where energy is applied to the joining films 31, 32, and the leaving groups present in the vicinities of the surfaces thereof are removed, so as to allow adhesive properties to appear in the joining films 31, 32; a stage where the joining film-fitted base materials 11, 12 are pasted each other in such a manner that the joining films 31, 32 are adhered, so as to obtain a joined body 5 in which the joining films 31, 32 are joined; and a stage where heating is performed till the metal atoms of the joining films 31, 32 are melted, so as to improve the joining strength of the joined body 5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a joining method and a joined body.

When joining (adhering) two members (base materials), conventionally, a method of using an adhesive such as an epoxy adhesive, a urethane adhesive, or a silicone adhesive is often used.
The adhesive generally exhibits excellent adhesiveness regardless of the material of the members to be joined. For this reason, members composed of various materials can be bonded in various combinations.

For example, a droplet discharge head (inkjet recording head) provided in an inkjet printer is assembled by bonding parts made of different materials such as a resin material, a metal material, and a silicon-based material using an adhesive. ing.
When the members are bonded together using the adhesive as described above, a liquid or paste adhesive is applied to the bonding surface, and the members are bonded together via the applied adhesive. Thereafter, the members are bonded to each other by curing (solidifying) the adhesive by the action of heat or light.

However, the joining using such an adhesive has the following problems.
・ Low bonding strength ・ Low dimensional accuracy ・ Long curing time, so it takes a long time to bond In addition, in many cases, it is necessary to use a primer to increase the bonding strength. Cost and complexity.

On the other hand, there is a solid bonding method as a bonding method that does not use an adhesive.
Solid bonding is a method of directly bonding members without an intermediate layer such as an adhesive (see, for example, Patent Document 1).
According to such solid bonding, since an intermediate layer such as an adhesive is not used, a bonded body with high dimensional accuracy can be obtained.

However, solid bonding has the following problems.
-There are restrictions on the material of the members to be joined-In the joining process, heat treatment is performed at a high temperature (for example, about 700 to 800 ° C)-The atmosphere in the joining process is limited to a reduced pressure atmosphere. There is a need for a method of joining members firmly with high dimensional accuracy and efficiently at low temperatures regardless of the material of the provided members.

In the field of such joining, there are cases where two members (base materials) are required to be electrically connected at the same time as being joined (conductive joining technique). Such a technique is used for connecting an electrode of an electronic component and a wiring pattern.
Conventionally, for such electrical connection, a conductive adhesive (ACP), a conductive film (ACF), or the like obtained by mixing conductive fine particles with an adhesive is used (see, for example, Patent Document 2). . However, in the connection using these bonding materials, since the conductive adhesive (conductive sheet) containing the same adhesive as described above is used, the same problem as the above-described adhesive occurs.

JP-A-5-82404 JP-A-7-205395

  An object of the present invention is to provide a bonding method capable of efficiently producing a bonded body that is firmly bonded with high dimensional accuracy at a low temperature, and a bonded body formed using the bonding method. is there.

Such an object is achieved by the present invention described below.
In the bonding method of the present invention, a first bonding film including a first metal atom and a leaving group composed of an organic component is formed on a first substrate to form a first bonding film-attached group. A material is obtained, and a second bonding film including a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component is formed on the second substrate. And obtaining a second substrate with a bonding film;
Energy is imparted to the first bonding film and the second bonding film, and the leaving group existing near the surfaces of the first bonding film and the second bonding film is removed from these bonding films. Causing the first bonding film and the second bonding film to exhibit adhesion by desorption, and
The first bonding film and the second bonding film-attached substrate are bonded together so that the first bonding film and the second bonding film are in close contact with each other, and the first bonding is performed. Obtaining a bonded body in which a film and the second bonding film are bonded;
And heating the first bonding film and the second bonding film until the second metal atoms are melted, thereby improving the bonding strength of the bonded body.
Thereby, the 1st base material and the 2nd base material can be joined firmly with high dimensional accuracy, and efficiently under low temperature.

In the bonding method of the present invention, a first bonding film including a first metal atom and a leaving group composed of an organic component is formed on a first substrate to form a first bonding film-attached group. A material is obtained, and a second bonding film including a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component is formed on the second substrate. And obtaining a second substrate with a bonding film;
A step of obtaining a laminate by superimposing the first substrate with a bonding film and the second substrate with a bonding film so that the first bonding film and the second bonding film are in close contact with each other. When,
Energy is imparted to the first bonding film and the second bonding film, and the leaving group present in the vicinity of the surfaces of the first bonding film and the second bonding film is converted into these bonding films. By desorbing from the first bonding film, the first bonding film and the second bonding film exhibit adhesiveness, and a bonded body in which the first bonding film and the second bonding film are bonded is obtained. Process,
And heating the first bonding film and the second bonding film until the second metal atoms are melted, thereby improving the bonding strength of the bonded body.

  Thereby, the 1st base material and the 2nd base material can be joined firmly with high dimensional accuracy, and efficiently under low temperature. Furthermore, in the state of the laminated body, the first substrate with a bonding film and the second substrate with a bonding film are not bonded. For this reason, a 1st base material with a bonding film and a 2nd base material with a bonding film can be shifted, and these relative positions can be adjusted. In this way, after superimposing the two substrates with the bonding film, these positions can be easily finely adjusted, so that the workability of position adjustment is improved, and the finally obtained bonded body The dimensional accuracy in the surface direction can be increased.

In the bonding method of the present invention, it is preferable that the melting point of the second metal atom is lower than 250 ° C.
Thereby, the joining strength of the joined body can be more reliably increased while reliably preventing the joined body from being altered or deteriorated by heat.
In the bonding method of the present invention, it is preferable that the second metal atom is at least one of indium, selenium, and tin.
Thereby, while being able to provide electroconductivity to a 2nd bonding film, the temperature at the time of heating a conjugate | zygote can be set to 250 degrees C or less, and it prevents reliably that a conjugate | zygote changes and deteriorates with heat. be able to.

In the bonding method of the present invention, each of the first bonding film and the second bonding film is formed from an organometallic material having the first metal atom and the second metal atom as a raw material. It is preferable to form a film using a phase growth method.
According to such a method, it is possible to form the first bonding film and the second bonding film having a uniform film thickness in a relatively simple process. In addition, the leaving group can be left relatively easily from the organic substance contained in the organometallic material.

In the bonding method of the present invention, it is preferable that the first bonding film and the second bonding film are each formed in a low reducing atmosphere.
As a result, the first base material and the second base material are formed on the first base material in a state in which a part of the organic matter contained in the organometallic material remains without forming a pure metal film. The bonding film and the second bonding film can be formed. That is, it is possible to form the first bonding film and the second bonding film that are excellent in both characteristics as the bonding film and the metal film.

In the bonding method of the present invention, it is preferable that the leaving group is one in which a part of the organic substance contained in the organometallic material remains.
By adopting a structure in which the residue remaining in the film when forming a film is used as a leaving group, it is not necessary to introduce the leaving group into the formed metal film, and the process is relatively simple. The first bonding film and the second bonding film can be formed.

In the bonding method of the present invention, the leaving group is composed of an atomic group containing a carbon atom as an essential component and containing at least one of a hydrogen atom, a nitrogen atom, a phosphorus atom, a sulfur atom and a halogen atom. preferable.
These leaving groups are relatively excellent in binding / leaving selectivity by applying energy. For this reason, a leaving group that can be removed relatively easily and uniformly by applying energy can be obtained, and the adhesiveness of the first bonding film and the second bonding film can be further enhanced. it can.
In the bonding method of the present invention, the leaving group preferably includes an alkyl group.
Since a leaving group including an alkyl group has high chemical stability, the first bonding film and the second bonding film having an alkyl group as the leaving group are excellent in weather resistance and chemical resistance. Become.

In the bonding method of the present invention, the organometallic material is preferably a β-diketone complex.
By using the β-diketone complex, the first bonding film and the second bonding film can be more reliably formed in a state where a part of the organic substance contained in the metal complex remains. In addition, β-diketone complexes are stable with low reactivity compared to metal complexes in which oxygen atoms are coordinated to metal atoms, and atoms other than oxygen atoms are coordinated to metal atoms such as carbon atoms. And easy to handle.
In the bonding method of the present invention, it is preferable that the first bonding film and the second bonding film each have conductivity.
Thereby, in a joined body, each joining film can be applied to the wiring with which a wiring board is provided, its terminal, etc.

In the bonding method of the present invention, it is further preferable that a difference in standard electrode potential between the first metal atom and the second metal atom is 3.0 mV or more.
Accordingly, since the second metal atom can act as a reducing agent for the first metal atom, the oxygen atom is extracted from the structure in which the first metal atoms are bonded to each other through the oxygen atom. A bond between the first metal atom and the second metal atom via the atom can be formed preferentially, thereby improving the bonding strength between the first bonding film and the second bonding film. Can do.
In the bonding method of the present invention, the first metal atom is preferably at least one of copper, aluminum, and silver.
Thereby, the first bonding film exhibits excellent conductivity.

In the bonding method of the present invention, the abundance ratio of the first metal atom and the second metal atom to the carbon atom in the first bonding film and the second bonding film is 3: 7 to 7, respectively. : 3 is preferable.
As a result, the stability of the first bonding film and the second bonding film is increased, so that the substrate with the first bonding film and the substrate with the second bonding film can be bonded more firmly. Become. Further, the first bonding film and the second bonding film can exhibit excellent conductivity.

In the bonding method of the present invention, each of the first bonding film and the second bonding film has an active hand after at least the leaving group present near the surface has been released from each bonding film. Preferably it occurs.
Thereby, the 1st base material with a joining film and the 2nd base material with a joining film can be joined firmly based on a chemical bond.
In the bonding method of the present invention, the active hand is preferably a dangling bond or a hydroxyl group.
Thereby, the 1st base material with a bonding film and the 2nd base material with a bonding film can be joined especially firmly.

In the bonding method of the present invention, it is preferable that an average thickness of each of the first bonding film and the second bonding film is 1 to 1000 nm.
Thereby, the 1st base material with a bonding film and the 2nd base material with a bonding film can be joined more firmly, preventing the dimensional accuracy of a joined object falling remarkably.
In the bonding method of the present invention, it is preferable that each of the first bonding film and the second bonding film is in a solid state having no fluidity.
Thereby, the dimensional accuracy of a joined body becomes remarkably high compared with the past. In addition, stronger bonding can be achieved in a shorter time than in the past.

In the bonding method of the present invention, it is preferable that the first base material and the second base material have a plate shape.
Thereby, the first base material and the second base material are easily bent, and when the first base material and the second base material are superposed, they can be sufficiently deformed along each other's shape. Become. For this reason, the adhesiveness when the first base material and the second base material are superposed is increased, and the joint strength in the finally obtained joined body is increased.

In the bonding method of the present invention, at least a portion of the first base material that forms the first bonding film and at least a portion of the second base material that forms the second bonding film are each made of a silicon material. It is preferable that the main material is a metal material or a glass material.
Thereby, sufficient bonding strength can be obtained without surface treatment.
In the bonding method of the present invention, the surface of the first base material on which the first bonding film is formed and the surface of the second base material on which the second bonding film is formed, It is preferable that a surface treatment for improving the adhesion between the first bonding film and the second bonding film is performed.
Accordingly, the surfaces of the first base material and the second base material are cleaned and activated, the bonding strength between the first bonding film and the first base material, and the second bonding film and the second base material. The joint strength with each other can be increased.
In the bonding method of the present invention, the surface treatment is preferably a plasma treatment.
Thereby, in order to form the first bonding film and the second bonding film on the first substrate and the second substrate, respectively, the surfaces of the first substrate and the second substrate are particularly optimized. can do.

In the bonding method of the present invention, intermediate layers are interposed between the first base material and the first bonding film and between the second base material and the second bonding film, respectively. It is preferable.
Thereby, a highly reliable joined body can be obtained.
In the bonding method of the present invention, it is preferable that the intermediate layer is composed of an oxide-based material as a main material.
Thereby, it is possible to particularly increase the bonding strength between the first base material and the first bonding film and the bonding strength between the second base material and the second bonding film.

In the bonding method of the present invention, the application of the energy is performed by irradiating the first bonding film and the second bonding film with energy rays, and heating the first bonding film and the second bonding film. The method is preferably performed by at least one of a method and a method of applying a compressive force to the first bonding film and the second bonding film.
Thereby, energy can be applied to the first bonding film and the second bonding film relatively easily and efficiently.

In the bonding method of the present invention, the energy beam is preferably ultraviolet light having a wavelength of 126 to 300 nm.
As a result, the amount of energy applied to the first bonding film and the second bonding film is optimized, so that the leaving groups in the first bonding film and the second bonding film can be reliably released. Can do. As a result, it is possible to prevent the first bonding film and the second bonding film from adhering while preventing the characteristics (mechanical characteristics, chemical characteristics, etc.) of the first bonding film and the second bonding film from deteriorating. Can be expressed.

In the bonding method of the present invention, it is preferable that the temperature at which the first bonding film and the second bonding film are heated is equal to or lower than the melting point of the second metal atom.
Thereby, it is possible to reliably increase the bonding strength while preventing the second bonding film from being melted and reliably preventing the bonded body from being altered or deteriorated by heat.
In the joining method of the present invention, the compressive force is preferably 0.2 to 10 MPa.
Accordingly, it is possible to reliably increase the bonding strength of the bonded body while preventing the first base material and the second base material from being damaged due to the pressure being too high.
In the bonding method of the present invention, it is preferable that the energy is applied in an air atmosphere.
Thereby, it is not necessary to spend time and cost to control the atmosphere, and energy can be applied more easily.

In the joining method of this invention, it is preferable to further have the process of performing the process which raises the joining strength more with respect to the said joined body.
Thereby, the joint strength of the joined body can be further improved.
In the bonding method of the present invention, it is preferable that the process of increasing the bonding strength is performed by at least one of a method of irradiating the bonded body with energy rays and a method of applying a compressive force to the bonded body. .
Thereby, the further improvement of the joining strength of a joined body can be aimed at easily.
The joined body of the present invention is characterized by being joined by the joining method of the present invention.
As a result, a highly reliable bonded body is obtained in which the first substrate with a bonding film and the second substrate with a bonding film are firmly bonded with high dimensional accuracy.

Hereinafter, a joining method and a joined object of the present invention are explained in detail based on a suitable embodiment shown in an accompanying drawing.
In the bonding method of the present invention, two base materials (first substrate 21 and second substrate 22) are bonded to each base material (first bonding film 31 and second bonding film 32). It is the method of obtaining a joined body by joining via.

Each bonding film formed on each base material contains a leaving group, and by applying energy, the leaving group present near the surface of each bonding film is released from each bonding film. is there. Each bonding film develops adhesiveness in a region to which surface energy is imparted by elimination of the leaving group.
Further, each bonding film contains metal atoms, and different types are selected so that the melting points are different.
Each bonding film having such characteristics is capable of bonding two substrates to each other firmly with high dimensional accuracy and efficiently at a low temperature, and the two substrates are bonded via the bonding film. The bonded body of the present invention is highly reliable bonded firmly by the bonding film.

Hereinafter, the bonding method of the present invention will be described step by step.
<Join method>
<< First Embodiment >>
First, a first embodiment of the bonding method of the present invention will be described.
FIGS. 1 to 3 are diagrams (longitudinal sectional views) for explaining the first embodiment of the bonding method of the present invention, and FIG. 4 is a portion showing the state of the bonding film before applying energy in the bonding method of the present invention FIG. 5 is an enlarged view showing a state of the bonding film after energy is applied in the bonding method of the present invention. In the following description, the upper side in FIGS.

  In the bonding method according to the present embodiment, a first bonding film is formed by forming a first bonding film including a first metal atom and a leaving group composed of an organic component on a first substrate. And a second bonding film comprising a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component on the second substrate. Forming a second substrate with a bonding film, and applying energy to the first bonding film and the second bonding film to form the first bonding film and the second bonding film Causing the first bonding film and the second bonding film to exhibit adhesiveness by detaching the leaving group existing near the surface of the bonding film from the bonding film; and the first bonding. Pasting the substrate with the first bonding film and the substrate with the second bonding film so that the film and the second bonding film are in close contact with each other; In addition, the step of obtaining a bonded body in which the first bonding film and the second bonding film are bonded, the first bonding film and the second bonding film, the second metal atom is A step of improving the bonding strength of the bonded body by heating until melting.

Hereinafter, each process of the joining method concerning this embodiment is demonstrated one by one.
[1] First, a first bonding film 31 including a first metal atom M1 and a leaving group composed of an organic component is formed on a first substrate (first base material) 21. While obtaining the base material 11 with the 1st joining film, on the 2nd board | substrate (2nd base material) 22, 2nd metal atom M2 whose melting | fusing point is lower than 1st metal atom M1, and an organic component The second bonding film 32 including the leaving group 303 configured is formed to obtain the second substrate 12 with the bonding film.

[1-1] First, a first substrate (first base material) 21 and a second substrate (second base material) 22 are prepared.
The first substrate 21 and the second substrate 22 are for bonding to each other through the first bonding film 31 and the second bonding film 32, and the first bonding film 31 and the second substrate 22 are respectively connected to each other. Any material may be used as long as the material has rigidity sufficient to support the bonding film 32 (hereinafter, these may be referred to as “bonding films 31, 32”).

  Specifically, each constituent material of the first substrate 21 and the second substrate 22 is a polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), or cyclic, respectively. Polyolefin, modified polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, polyamideimide, polycarbonate, poly- (4-methylpentene-1), ionomer, acrylic resin, polymethyl methacrylate, acrylonitrile-butadiene-styrene Copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH) Polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT), polyether, polyether ketone (PEK), polyether ether ketone (PEEK), polyether imide, Polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluorine resins, styrene, Polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyiso Various thermoplastic elastomers such as len series, fluoro rubber series, chlorinated polyethylene series, epoxy resins, phenol resins, urea resins, melamine resins, aramid resins, unsaturated polyesters, silicone resins, polyurethanes, etc. Resin materials such as copolymers, blends, polymer alloys, Fe, Ni, Co, Cr, Mn, Zn, Pt, Au, Ag, Cu, Pd, Al, W, Ti, V, Mo, Nb, Zr , Metals such as Pr, Nd, Sm, or alloys containing these metals, carbon steel, stainless steel, indium tin oxide (ITO), metal-based materials such as gallium arsenide, single crystal silicon, polycrystalline silicon, Silicon-based materials such as amorphous silicon, silicate glass (quartz glass), alkali silicate glass, soda lime glass, potash lime Glass materials such as glass, lead (alkali) glass, barium glass, borosilicate glass, alumina, zirconia, ferrite, silicon nitride, aluminum nitride, boron nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, tungsten carbide Ceramic materials such as graphite, carbon materials such as graphite, or composite materials in which one or more of these materials are combined.

In addition, the first substrate 21 and the second substrate 22 are respectively subjected to plating treatment such as Ni plating, passivation treatment such as chromate treatment, or nitriding treatment on the surfaces thereof. Also good.
In addition, the first substrate 21 and the second substrate 22 may be the same or different from each other, but the respective thermal expansion coefficients of the first substrate 21 and the second substrate 22 are the same. It is preferable to select one that is approximately equal. If the thermal expansion coefficients of the first substrate 21 and the second substrate 22 are substantially equal, the bonding interface when the first substrate 11 with the bonding film and the second bonding film substrate 12 are bonded together. It is difficult to generate stress associated with thermal expansion. As a result, it is possible to reliably prevent problems such as peeling in the finally obtained bonded body 5.
Furthermore, it is preferable that the first substrate 21 and the second substrate 22 have different rigidity. Thereby, the first substrate 21 and the second substrate 22 can be bonded more firmly through the bonding films 31 and 32.

Moreover, it is preferable that at least one of the first substrate 21 and the second substrate 22 is made of a resin material. Due to its flexibility, the resin material can relieve stress (for example, stress accompanying thermal expansion) generated at the bonding interface when the first substrate 21 and the second substrate 22 are bonded. For this reason, it becomes difficult to destroy the bonding interface, and as a result, the bonded body 5 having high bonding strength can be obtained.
Further, the first substrate 21 and the second substrate 22 may have any shape as long as they have surfaces that support the first bonding film 31 and the second bonding film 32, respectively. The shape is not limited. That is, the shape of the first substrate 21 and the second substrate 22 may be, for example, a block shape or a rod shape.

  In addition, as shown to Fig.1 (a), in this embodiment, the 1st board | substrate 21 and the 2nd board | substrate 22 have comprised plate shape, respectively. Thereby, the first substrate 21 and the second substrate 22 are easily bent, and when the first substrate 21 and the second substrate 22 are superposed, they can be sufficiently deformed along the shape of each other. Become. For this reason, the adhesiveness when the 1st board | substrate 21 and the 2nd board | substrate 22 are piled up becomes high, and the joining strength in the joined body 5 finally obtained becomes high.

Further, the bending of the first substrate 21 and the second substrate 22 can alleviate the stress generated at the bonding interface to some extent.
In this case, the average thicknesses of the first substrate 21 and the second substrate 22 are not particularly limited, but are preferably about 0.01 to 10 mm, more preferably about 0.1 to 3 mm. preferable.

[1-2] Next, if necessary, at least in the region where the first bonding film 31 is to be formed, the first bonding film according to the constituent material of the first substrate 21. A surface treatment is performed to improve the adhesion with 31.
Examples of the surface treatment include physical surface treatment such as sputtering treatment and blast treatment, plasma treatment using oxygen plasma, nitrogen plasma, etc., corona discharge treatment, etching treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, ozone Examples include chemical surface treatment such as exposure treatment, or a combination of these. By performing such treatment, the region where the first bonding film 31 of the first substrate 21 is to be formed can be cleaned and the region can be activated. Thereby, the bonding strength between the first substrate 21 and the first bonding film 31 can be increased.

In addition, by using plasma treatment among these surface treatments, the surface of the first substrate 21 can be particularly optimized in order to form the first bonding film 31.
In addition, when the 1st board | substrate 21 which performs surface treatment is comprised with the resin material (polymer material), especially a corona discharge process, a nitrogen plasma process, etc. are used suitably.
In addition, depending on the constituent material of the first substrate 21, the bonding strength with the first bonding film 31 is sufficiently high without performing the surface treatment as described above. Examples of the constituent material of the first substrate 21 that can obtain such an effect include materials mainly composed of various metal materials, various silicon materials, various glass materials and the like as described above.

The surface of the first substrate 21 made of such a material is covered with an oxide film, and a relatively active hydroxyl group is bonded to the surface of the oxide film. Therefore, when the first substrate 21 made of such a material is used, the bonding strength between the first substrate 21 and the first bonding film 31 can be increased without performing the surface treatment as described above. Can do.
In this case, the entire first substrate 21 may not be made of the material as described above, and at least the vicinity of the surface of the region where the first bonding film 31 is to be formed is made of the material as described above. It only has to be done.

Further, instead of the surface treatment, an intermediate layer may be formed in advance in at least a region where the first bonding film 31 is to be formed on the first substrate 21.
The intermediate layer may have any function, and is not particularly limited. For example, the intermediate layer has a function of improving adhesion to the first bonding film 31, a cushioning function (buffer function), and a stress concentration. A function of relaxing the first bonding film 31, a function of promoting the film growth of the first bonding film 31 (seed layer), a function of protecting the first bonding film 31 (barrier layer), etc. Those having the following are preferred. The first substrate 21 and the first bonding film 31 are bonded through such an intermediate layer, and the bonded body 5 with high reliability can be obtained.

Examples of the constituent material of the intermediate layer include metal materials such as aluminum, titanium, tungsten, copper and alloys thereof, metal oxides, metal nitrides, oxide materials such as silicon oxides, metal nitrides, Nitride-based materials such as silicon nitride, carbon-based materials such as graphite and diamond-like carbon, silane coupling agents, thiol-based compounds, metal alkoxides, self-assembled film materials such as metal-halogen compounds, and resin-based materials Examples thereof include resin materials such as adhesives, resin films, resin coating materials, various rubber materials, and various elastomers, and one or more of these can be used in combination.
Among the intermediate layers made of these various materials, the intermediate layer made of an oxide-based material particularly increases the bonding strength between the first substrate 21 and the first bonding film 31. be able to.

[1-3] Next, as in the case of the first substrate 21, according to the constituent material of the second substrate 22 in the region where the second bonding film 32 of the second substrate 22 is to be formed, if necessary. Then, a surface treatment for improving the adhesion between the second substrate 22 and the second bonding film 32 is performed.
Thereby, the bonding strength between the second substrate 22 and the second bonding film 32 can be further increased. As the surface treatment, the same treatment as the surface treatment described above performed on the first substrate 21 can be applied.

In addition, depending on the constituent material of the second substrate 22, the bonding strength between the second substrate 22 and the second bonding film 32 is sufficiently high without performing the surface treatment as described above. The constituent material of the second substrate 22 that can obtain such an effect is the same as the constituent material of the first substrate 21 described above, that is, various metal-based materials, various silicon-based materials, various glass-based materials, and the like. Can be used.
In addition, a second substrate that can be particularly strongly bonded to the second bonding film 32 by appropriately performing various surface treatments as described above so as to obtain a surface having such a material. 22 is obtained.

Further, instead of the surface treatment, an intermediate layer having a function of improving the adhesion with the second bonding film 32 is formed in advance in the region where the second bonding film 32 of the second substrate 22 is to be formed. It is preferable to keep it. As a result, the second substrate 22 and the second bonding film 32 are bonded via the intermediate layer, and finally, the bonded body 5 with higher bonding strength can be obtained.
As the constituent material of the intermediate layer, the same constituent material as that of the intermediate layer formed on the first substrate 21 described above can be used.

[1-4] Next, as shown in FIG. 1 (a), by forming the first bonding film 31 on the first substrate 21, the first substrate 11 with the bonding film is obtained. By forming the second bonding film 32 on the second substrate 22, the base material 12 with the second bonding film is obtained.
Here, the first bonding film 31 and the second bonding film 32 respectively formed on the first substrate 21 and the second substrate 22 are between the first substrate 21 and the second substrate 22. It is located and bears joining of these substrates 21 and 22.

The first bonding film 31 includes a first metal atom M1 and a leaving group 303 composed of an organic component, and the second bonding film 32 has a melting point higher than that of the first metal atom M1. Second metal atom M2 having a low height and a leaving group composed of an organic component.
When energy is applied to the bonding films 31 and 32 having such a configuration, a leaving group existing in the vicinity of the surfaces 351 and 352 of the bonding films 31 and 32 is released from the bonding films 31 and 32. Each of the bonding films 31 and 32 has a function of exhibiting adhesiveness in a region to which energy of the surface is imparted by elimination of the leaving group.
The bonding method of the present invention is characterized in that the bonded body 5 is obtained using the first bonding film 31 and the second bonding film 32.
The configuration of the first bonding film 31 and the second bonding film 32 will be described in detail later.

[2] Next, energy is applied to the first bonding film 31 of the first substrate 11 with the bonding film and the second bonding film 32 of the substrate 12 with the second bonding film, respectively.
Here, when energy is applied to each of the bonding films 31 and 32, in each of the bonding films 31 and 32, as shown in FIGS. After the release from the vicinity of the surfaces 351 and 352 and the elimination of the leaving group 303, active hands 304 are generated in the vicinity of the surfaces 351 and 352 of the bonding films 31 and 32. As a result, adhesiveness is developed on the surfaces 351 and 352 of the bonding films 31 and 32. FIG. 4 shows the case where the leaving group 303 is a methyl group.
The base material 11 with the first bonding film and the base material 12 with the second bonding film in such a state are brought into chemical bonding by bringing the first bonding film 31 and the second bonding film 32 into close contact with each other. Based on this, they can be joined to each other.

  Here, the energy applied to the first bonding film 31 and the second bonding film 32 may be applied using any method. For example, the first bonding film 31 and the second bonding film 32 may be applied. A method of irradiating the bonding film 32 with energy rays, a method of heating the first bonding film 31 and the second bonding film 32, and a compressive force (physical energy) on the first bonding film 31 and the second bonding film 32 , A method of exposing the first bonding film 31 and the second bonding film 32 to plasma (applying plasma energy), and a method of exposing the first bonding film 31 and the second bonding film 32 to ozone gas (chemical) And the like). Among these, in the present embodiment, as a method for applying energy to the first bonding film 31 and the second bonding film 32, in particular, a method for irradiating the first bonding film 31 and the second bonding film 32 with energy rays. Is preferably used. Since this method can apply energy relatively easily and efficiently to the first bonding film 31 and the second bonding film 32, it is preferably used as a method for applying energy.

Among these, as energy rays, for example, light such as ultraviolet rays and laser beams, X-rays, γ rays, electron beams, particle beams such as ion beams, etc., or a combination of two or more of these energy rays Is mentioned.
Among these energy rays, it is particularly preferable to use ultraviolet rays having a wavelength of about 126 to 300 nm (see FIG. 1B). With ultraviolet rays within such a range, the amount of energy applied is optimized, so that the leaving group 303 in the first bonding film 31 and the second bonding film 32 can be reliably released. Accordingly, the first bonding film 31 and the second bonding film 32 are prevented from being deteriorated in the characteristics (mechanical characteristics, chemical characteristics, etc.) of the first bonding film 31 and the second bonding film 32. Adhesiveness can be reliably expressed.

In addition, since ultraviolet rays can be processed in a short time without unevenness, the leaving group 303 can be efficiently eliminated. Furthermore, ultraviolet rays also have the advantage that they can be generated with simple equipment such as UV lamps.
The wavelength of the ultraviolet light is more preferably about 126 to 200 nm.
Further, when a UV lamp is used, its output varies depending on the areas of the first bonding film 31 and the second bonding film 32, but is preferably about 1 mW / cm ^{2 to} 1 W / cm ^2. More preferably, it is about / cm ^{2 to} 50 mW / cm ² . In this case, the separation distance between the UV lamp and each of the bonding films 31 and 32 is preferably about 1 to 10 mm, and more preferably about 1 to 5 mm.

In addition, the time for irradiating the ultraviolet rays is such a time that the leaving groups 303 near the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 can be released, that is, the first bonding film 31. The second bonding film 32 is preferably set to a time that does not irradiate the ultraviolet rays more than necessary. Thereby, it is possible to effectively prevent the first bonding film 31 and the second bonding film 32 from being altered or deteriorated. Specifically, although it varies slightly depending on the amount of ultraviolet light, the constituent materials of the first bonding film 31 and the second bonding film 32, etc., it is preferably about 0.5 to 30 minutes, and preferably 1 to 10 minutes. More preferred is the degree.
Moreover, although an ultraviolet-ray may be irradiated continuously in time, you may irradiate intermittently (pulse form).

  On the other hand, examples of the laser light include a pulsed laser (pulse laser) such as an excimer laser, a continuous wave laser such as a carbon dioxide laser, and a semiconductor laser. Among these, a pulse laser is preferably used. In the pulse laser, heat hardly accumulates with time in the portions of the first bonding film 31 and the second bonding film 32 that have been irradiated with the laser beam. Deterioration can be reliably prevented. That is, according to the pulse laser, it is possible to prevent the heat accumulated in the first bonding film 31 and the second bonding film 32 from being affected.

  The pulse width of the pulse laser is preferably as short as possible in consideration of the influence of heat. Specifically, the pulse width is preferably 1 ps (picosecond) or less, and more preferably 500 fs (femtosecond) or less. When the pulse width is within the above range, the influence of heat generated in the first bonding film 31 and the second bonding film 32 due to laser light irradiation can be accurately suppressed. A pulse laser having a pulse width as small as the above range is called a “femtosecond laser”.

The wavelength of the laser light is not particularly limited, but is preferably about 200 to 1200 nm, and more preferably about 400 to 1000 nm.
In the case of a pulse laser, the peak output of the laser light varies depending on the pulse width, but is preferably about 0.1 to 10 W, and more preferably about 1 to 5 W.
Furthermore, the repetition frequency of the pulse laser is preferably about 0.1 to 100 kHz, and more preferably about 1 to 10 kHz. By setting the frequency of the pulse laser within the above range, the temperature of the portion irradiated with the laser light is remarkably increased, and a part of the organic components contained in the first bonding film 31 and the second bonding film 32 is reduced. In the remaining state, the leaving group 303 can be reliably cut from the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32.

  The various conditions of such laser light are such that the temperature of the portion irradiated with the laser light is preferably from room temperature (room temperature) to about 600 ° C., more preferably about 200 to 600 ° C., and even more preferably 300 to 400 ° C. It is preferable to adjust as appropriate. As a result, the temperature of the portion irradiated with the laser beam is remarkably increased, and the leaving group 303 is moved in the state where a part of the organic component contained in the first bonding film 31 and the second bonding film 32 remains. The first bonding film 31 and the second bonding film 32 can be reliably cut.

  In addition, the laser light applied to the first bonding film 31 and the second bonding film 32 is in a state where the focal points are aligned with the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32. It is preferable to scan along the surfaces 351 and 352. Thereby, the heat generated by the laser light irradiation is accumulated locally in the vicinity of the surfaces 351 and 352. As a result, the leaving group 303 present on the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 can be selectively released.

Further, the energy beam irradiation to the first bonding film 31 and the second bonding film 32 may be performed in any atmosphere, and specifically, air, an oxidizing gas atmosphere such as oxygen, hydrogen A reducing gas atmosphere, an inert gas atmosphere such as nitrogen or argon, or a reduced pressure (vacuum) atmosphere in which these atmospheres are decompressed. Among these, it is particularly preferable to perform in an air atmosphere. Thereby, it is not necessary to spend time and cost to control the atmosphere, and irradiation of energy rays can be performed more easily.
Thus, according to the method of irradiating energy rays, it is easy to selectively apply energy to the vicinity of the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32. For example, it is possible to prevent deterioration and deterioration of the substrates 21 and 22 and the bonding films 31 and 32 due to energy application.

  Moreover, according to the method of irradiating energy rays, the magnitude of energy to be applied can be easily adjusted with high accuracy. For this reason, it becomes possible to adjust the desorption amount of the leaving group 303 desorbed from the first bonding film 31 and the second bonding film 32. By adjusting the amount of elimination of the leaving group 303 in this manner, the bonding strength between the first substrate with a bonding film 11 and the second substrate with a bonding film 12 can be easily controlled. .

That is, by increasing the amount of elimination of the leaving group 303, more active hands are generated in the vicinity of the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32. The adhesiveness expressed in the bonding film 31 and the second bonding film 32 can be further increased. On the other hand, by reducing the amount of elimination of the leaving group 303, the number of active hands generated in the vicinity of the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 is reduced, and the first bonding film 31. In addition, the adhesiveness developed in the second bonding film 32 can be suppressed.
In addition, in order to adjust the magnitude | size of the energy to provide, what is necessary is just to adjust conditions, such as the kind of energy beam, the output of an energy beam, the irradiation time of an energy beam.
Furthermore, according to the method of irradiating energy rays, a large amount of energy can be applied in a short time, so that the energy can be applied more efficiently.

  Here, the first bonding film 31 and the second bonding film 32 before energy is applied have a leaving group 303 in the vicinity of their surfaces 351 and 352, as shown in FIG. When energy is applied to the first bonding film 31 and the second bonding film 32, the leaving group 303 (methyl group in FIG. 4) is released from the first bonding film 31 and the second bonding film 32. . As a result, as shown in FIG. 5, active hands 304 are generated on the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 and are activated. As a result, adhesiveness develops on the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32.

  In this specification, the state in which the first bonding film 31 and the second bonding film 32 are “activated” means that the first bonding film 31 and the second bonding film 32 are as described above. Each of the surfaces 351 and 352 and the internal leaving group 303 are desorbed, and bonds that are not terminated in the constituent atoms of the bonding films 31 and 32 (hereinafter also referred to as “unbonded hands” or “dangling bonds”). In addition to the state in which the unbonded hands are terminated by a hydroxyl group (OH group), and the state in which these states are mixed, the first bonding film 31 and the second bonding are included. Let us say that the membrane 32 is “activated”.

Therefore, the active hand 304 means a dangling bond (dangling bond) or a dangling bond terminated by a hydroxyl group as shown in FIG. If such active hands 304 are present, the first bonding film 31 and the second bonding film 32 can be bonded particularly firmly.
The latter state (the state in which the dangling bonds are terminated by a hydroxyl group) is obtained by, for example, irradiating the bonding films 31 and 32 with energy rays in the atmospheric air so that moisture in the air is not bonded. It is easily generated by terminating the hand.

  In the present embodiment, the first bonding film 31 and the second bonding film 32 are preliminarily bonded to the first bonding film 31 and the second bonding film 32 before the first bonding film-coated substrate 11 and the second bonding film substrate 12 are bonded together. Although the case where energy is applied is described, such energy application is performed when the first substrate 11 with a bonding film and the second substrate 12 with a bonding film are bonded (overlapped) or bonded. It may be performed after (overlapping). Such a case will be described in a second embodiment to be described later.

  [3] Next, the substrate 11 with the first bonding film and the second bonding are so arranged that the activated first bonding film 31 and second bonding film 32 (each bonding film) are in close contact with each other. The base material 12 with a film | membrane and (base materials with each bonding film) are bonded together (refer FIG.1 (c)). Thereby, in the said process [2], since adhesiveness has expressed in the 1st joining film 31 and the 2nd joining film 32, the 1st joining film 31 and the 2nd joining film 32 are chemical. Combined and integrated.

  Further, the active states of the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 activated in the step [2] are gradually reduced over time. For this reason, it is preferable to perform this process [3] as soon as possible after completion of the process [2]. Specifically, after the completion of the step [2], the step [3] is preferably performed within 60 minutes, and more preferably within 5 minutes. Within this time, the surfaces of the first bonding film 31 and the second bonding film 32 are maintained in a sufficiently active state. Therefore, in this step, the first substrate 11 with the bonding film (first The bonding body 31) and the second substrate 12 with the bonding film (second bonding film 32) can be bonded together to reliably obtain the bonded body 5.

  In other words, the first bonding film 31 and the second bonding film 32 before activation are the leaving group composed of the first metal atom M1 and the second metal atom M2 and the organic component, respectively. Therefore, it is chemically relatively stable and has excellent weather resistance. Therefore, the first bonding film 31 and the second bonding film 32 before being activated are suitable for long-term storage. Therefore, a large amount of the first substrate 11 with the bonding film 11 and the second substrate 12 with the bonding film including the first bonding film 31 and the second bonding film 32 are manufactured and purchased and stored. In addition, it is effective from the viewpoint of manufacturing efficiency of the bonded body 5 if the energy described in the step [2] is applied to only a necessary number immediately before performing the bonding in the present step.

[4] Next, as shown in FIG. 2A, the first bonding film 31 and the second bonding film 32 are heated.
In the present invention, the melting point of the first metal atom and the second metal atom respectively contained in the first bonding film 31 and the second bonding film 32 is higher than that of the second metal atom M2. Is selected and is heated to a temperature at which the second metal atom M2 is selectively melted.
Thereby, the second metal atoms M2 contained in the second bonding film 32 diffuse to the first bonding film 31 side, and as a result, the first bonding film 31 and the first bonding film 31 as shown in FIG. A bonded body 5 with improved bonding strength with the second bonding film 32 can be obtained. The mechanism for improving the bonding strength of the bonded body 5 will be described in detail later.

The temperature at which the bonded body 5 is heated is particularly limited as long as it is higher than the melting point of the second metal atom M2, lower than the first metal atom M1, and lower than the heat resistance temperature of the bonded body 5. However, it is preferably 250 ° C. or lower, more preferably about 100 to 160 ° C. By heating at a temperature in such a range, it is possible to reliably increase the bonding strength of the bonded body 5 while reliably preventing the bonded body 5 from being altered or deteriorated by heat.
The heating time is not particularly limited, but is preferably about 1 to 30 minutes.
Furthermore, the first bonding film 31 and the second bonding film 32 may be heated by any method. For example, a method of heating the bonded body 5 using a heater, a method of irradiating the bonded body 5 with infrared rays It can be heated by various methods such as bringing the joined body 5 into contact with a flame.

In the joined body 5 obtained in this way, the adhesive mainly used in the conventional joining method is not a bond based on a physical bond such as an anchor effect, but a strong bond such as a covalent bond. Based on the chemical bond, the first substrate 11 with the bonding film and the second substrate 12 with the bonding film are bonded. For this reason, the joined body 5 is extremely difficult to peel off, and joining unevenness or the like hardly occurs.
Further, according to such a method, unlike the conventional solid bonding, since the heat treatment at a high temperature (for example, 700 ° C. or higher) is not required, the first substrate 21 made of a material having low heat resistance and the first substrate 21 Two substrates 22 can also be used for bonding.

As described above, the first base material 11 with the bonding film and the second base material 12 with the bonding film are bonded to obtain the bonded body 5 as shown in FIG.
In FIG. 2B, the second substrate 12 with the bonding film is overlaid so as to cover the entire surface of the first bonding film 31 of the substrate 11 with the first bonding film. The general positions may be shifted from each other. That is, the base material 11 with the first bonding film and the base material 12 with the second bonding film may be overlapped so that the base material 12 with the second bonding film protrudes from the first bonding film 31. .

  In addition, in the conventional solid bonding where the silicon substrates are directly bonded to each other, even if the surface of the substrate used for bonding is activated, the active state is an extremely short time of about several seconds to several tens of seconds in the atmosphere. It could only be maintained. For this reason, there has been a problem that it is not possible to sufficiently secure the time required for operations such as bonding the two substrates to be bonded after the surface activation.

On the other hand, according to the present invention, the active state can be maintained for a relatively long time. For this reason, the time required for the bonding operation can be sufficiently secured, and the efficiency of the bonding operation can be increased. The fact that the active state can be maintained for a relatively long time is presumed to be due to the stabilization of the activated state in which the leaving group 303 composed of the organic component is eliminated. The
In addition, since the first substrate 21 and the second substrate 22 are bonded via the first bonding film 31 and the second bonding film 32, the configuration of the first substrate 21 and the second substrate 22. There is also an advantage that there are no restrictions on the material.

From the above, according to the present invention, the range of selection of each constituent material of the first substrate 21 and the second substrate 22 can be increased.
Further, since solid bonding does not involve a bonding film, when there is a large difference in the thermal expansion coefficient between the first substrate 21 and the second substrate 22, stress based on the difference is concentrated on the bonding interface. However, in the joined body (joined body of the present invention) 5, stress concentration is relaxed by the first joining film 31 and the second joining film 32, so that the occurrence of peeling is accurately performed. Can be suppressed or prevented.

In the joined body 5 obtained in this way, the joining strength between the first substrate 21 and the second substrate 22 is preferably 5 MPa (50 kgf / cm ² ) or more, preferably 10 MPa (100 kgf / cm ^2). ) Or more. The bonded body 5 having such bonding strength can sufficiently prevent the peeling. As will be described later, for example, when a droplet discharge head is configured using the joined body 5, a droplet discharge head having excellent durability can be obtained. Further, according to the bonding method of the present invention, the bonded body 5 in which the first substrate 21 and the second substrate 22 are bonded with such a large bonding strength can be efficiently produced.

  In addition, in this step [4], at the same time when the bonding strength of the bonded body 5 is improved or after the bonding strength of the bonded body 5 is improved, If necessary, at least one of the following two steps ([5A] and [5B]) (the bonding strength of the bonded body 5 is increased) with respect to the second bonding film substrate 12 laminate. Step) may be performed. Thereby, the joint strength of the joined body 5 can be further improved.

[5A] As shown in FIG. 3A, the obtained bonded body 5 is pressurized in a direction in which the first substrate 21 and the second substrate 22 approach each other.
Thereby, the diffusion of the second metal atom M2 toward the first bonding film 31 is further promoted, so that the bonding strength in the bonded body 5 can be further increased.
At this time, the pressure at the time of pressurizing the bonded body 5 is a pressure that does not damage the bonded body 5 and is preferably as high as possible. Thereby, the joint strength in the joined body 5 can be increased in proportion to the pressure.

In addition, what is necessary is just to adjust this pressure suitably according to conditions, such as each constituent material of each of the 1st board | substrate 21 and the 2nd board | substrate 22, each thickness, and a joining apparatus. Specifically, it is preferably about 0.2 to 10 MPa, preferably about 1 to 5 MPa, although it varies slightly depending on the constituent materials and thicknesses of the first substrate 21 and the second substrate 22. Is more preferable. Thereby, the joining strength of the joined body 5 can be reliably increased. Note that this pressure may exceed the upper limit, but depending on the constituent materials of the first substrate 21 and the second substrate 22, the first substrate 21 and the second substrate 22 may be damaged. There is a fear.
The time for pressurization is not particularly limited, but is preferably about 10 seconds to 30 minutes. In addition, what is necessary is just to change suitably the time to pressurize according to the pressure at the time of pressurizing. Specifically, the higher the pressure at which the bonded body 5 is pressed, the more the bonding strength can be improved even if the pressing time is shortened.

[5B] As shown in FIG. 3B, the obtained bonded body 5 is irradiated with ultraviolet rays.
Thereby, the chemical bond formed between the second metal atom M2 diffused to the first bonding film 31 side and the first metal atom M1 included in the first bonding film 31 is increased. The joint strength of the joined body 5 can be particularly increased.
The conditions of the ultraviolet rays irradiated at this time may be equivalent to the conditions of the ultraviolet rays shown in the step [2].
Moreover, when performing this process [5B], it is required for either one of the 1st board | substrate 21 and the 2nd board | substrate 22 to have translucency. Then, the first bonding film 31 and the second bonding film 32 can be reliably irradiated with ultraviolet rays by irradiating the ultraviolet rays from the light-transmitting substrate side.

  By performing the above steps, the dehydration condensation of hydroxyl groups and the recombination of dangling bonds on the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 are promoted. Then, the integration of the first bonding film 31 and the second bonding film 32 further proceeds. As a result, the bonded body 5 can include a bonding film in which the first bonding film 31 and the second bonding film 32 are almost completely integrated.

Here, as described above, the bonding method of the present invention is characterized in that the first substrate 21 and the second substrate 22 are bonded using the first bonding film 31 and the second bonding film 32. Have. Hereinafter, the first bonding film 31 and the second bonding film 32 will be described in detail.
The first bonding film 31 includes a first metal atom M1 and a leaving group 303 composed of an organic component. The second bonding film 32 includes a second metal atom M2 having a melting point lower than that of the first metal atom M1 and a leaving group 303 composed of an organic component.

  In other words, the first bonding film 31 and the second bonding film 32 are different in the type of metal atoms contained, and the second metal atom M2 has a lower melting point than the first metal atom M1. Other than the above, the bonding film has the same configuration including the leaving group 303 (see FIG. 3). When energy is applied to the first bonding film 31 and the second bonding film 32, the leaving group 303 forms at least the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32. As shown in FIG. 4, active hands 304 are generated near at least the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 as shown in FIG.

  Then, active hands 304 are generated in the vicinity of the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32, so that the surfaces 351 and 352 of the first bonding film 31 and the second bonding film 32 are generated. Adhesiveness is developed. When such adhesiveness develops, the first substrate 11 with the bonding film and the second substrate 12 with the bonding film are more strongly reinforced with the first bonding film 31 and the second bonding film 32 with high dimensional accuracy. It becomes possible to join efficiently.

  In the present invention, in particular, the second metal atom M2 has a lower melting point than the first metal atom M1, and in the step [4], the first bonding film 31 and the second bonding film 32 are formed in the first step. When the second metal atom M2 is heated until it is melted, the second metal atom M2 diffuses on the first bonding film 31 side, so that the obtained bonded body 5 includes the first bonding film 31 and the second bonding film 31. The bonding film 32 is more firmly bonded.

  Further, the first bonding film 31 and the second bonding film 32 each include a first metal atom M1 and a second metal atom M2 and a leaving group 303 composed of an organic component, that is, Since it is an organic metal film, it is a strong film that is difficult to deform. For this reason, the first bonding film 31 and the second bonding film 32 themselves have high dimensional accuracy, and the bonded body 5 finally obtained also has high dimensional accuracy.

The first bonding film 31 and the second bonding film 32 are in a solid state having no fluidity. For this reason, the thickness of the adhesive layer (the first bonding film 31 and the second bonding film 32) is higher than that of a liquid or viscous liquid (semi-solid) adhesive having fluidity, which has been conventionally used. The shape hardly changes. Therefore, the dimensional accuracy of the joined body 5 obtained by using the first base material 11 with the bonding film and the base material 12 with the bonding film is remarkably higher than the conventional one. Furthermore, since the time required for curing the adhesive is not required, strong bonding can be achieved in a short time.
In the present invention, it is preferable that the first bonding film 31 and the second bonding film 32 have conductivity. Thereby, in the bonded body 5 to be described later, the first bonding film 31 and the second bonding film 32 can be applied to wirings provided in the wiring board, terminals thereof, and the like.

The first metal atom M1 and the second metal atom M2 and the leaving group 303 are formed so that the functions as the first bonding film 31 and the second bonding film 32 as described above are suitably exhibited. A combination is appropriately selected.
Specifically, as the first metal atom M1 and the second metal atom M2, for example, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo , Tc, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Os, Ir, Pt, Au, various lanthanoid elements, transition metal elements such as various actinoid elements, Li, Be, Na, Mg, Al , K, Ca, Zn, Ga, Rb, Sr, Cd, In, Sn, Sb, Cs, Ba, Tl, Pb, Bi, Po, and other typical metal elements, as well as metal selenium and metal tellurium Typical non-metals having such metallic properties can also be used.

  Here, for example, transition metal elements are similar in physical properties because they are different only in the number of outermost electrons among the transition metal elements. Transition metals generally have high hardness and melting point, and high electrical conductivity and thermal conductivity. For this reason, when a transition metal element is used as each metal atom, the adhesiveness expressed in the first bonding film 31 and the second bonding film 32 can be further enhanced, and the first bonding film 31 and the second bonding film 32 can be improved. The conductivity of the bonding film 32 can be further increased.

Among these, in consideration of the characteristics to be imparted to the first bonding film 31 and the second bonding film 32, the second metal atom M2 has a lower melting point than the first metal atom M1. The first metal atom M1 and the second metal atom M2 are selected.
For example, when the first bonding film 31 is used in combination with one or more of Cu, Al and Ag as the first metal atom M1 in order to exhibit excellent conductivity, the conductivity In consideration of the properties, a metal atom having a lower melting point than these is selected as the second metal atom M2.

More specifically, when, for example, Cu is selected as the first metal atom M1, in consideration of conductivity and melting point, the second metal atom M2 includes In, Se, Sn, Pb, Zn, Al, etc. A combination of one or more of these is used. Among these, since the temperature at which the bonded body 5 is heated in the step [4] is preferably 250 ° C. or less in consideration of the heat-resistant temperature of the bonded body 5, the second metal atom M 2 is 250 ° C. A combination of one or more of In (156 ° C.), Se (220 ° C.) and Sn (232 ° C.) having a lower melting point is preferably used.
Of these, the first bonding film 31 and the second bonding film 32 containing metal atoms such as Cu, Al, Ag, Zn, Pb and In are formed by using a metal organic chemical vapor deposition method to be described later. In the case of forming a film, the first bonding film 31 and the second bonding film 32 having a relatively easy and uniform film thickness can be formed using a metal complex containing these metal atoms as a raw material. .

  Here, in the present invention, by applying energy to the first bonding film 31 and the second bonding film 32 in the step [2], adhesiveness is expressed on each of the surfaces 351 and 352, and In the step [3], the first bonding film 31 and the second bonding film 32 are bonded to each other due to this adhesiveness in either or both of the following two mechanisms (i) and (ii). It is guessed that it is based on.

  (I) For example, the case where hydroxyl groups are exposed on the surface 351 of the first bonding film 31 and the surface 352 of the second bonding film 32 will be described as an example. When these are bonded so that the first bonding film 31 and the second bonding film 32 of the second substrate 12 with the bonding film are in contact with each other, the first bonding film 31 exists on the surface 351 of the first bonding film 31. The hydroxyl group and the hydroxyl group present on the surface 352 of the second bonding film 32 attract each other by hydrogen bonding, and an attractive force is generated between the hydroxyl groups. It is presumed that the first base material 11 with the bonding film and the second base material 12 with the bonding film are bonded by this attractive force.

  Further, the hydroxyl groups attracting each other by the hydrogen bond are cleaved from the surface with dehydration condensation depending on the temperature condition or the like. As a result, at the contact interface between the base material 11 with the first bonding film and the base material 12 with the second bonding film, the bonding hands to which the hydroxyl groups are bonded are bonded. Thereby, it is guessed that the 1st base material 11 with a bonding film and the 2nd base material 12 with a bonding film are joined more firmly.

  (Ii) When the base material 11 with the first bonding film and the base material 12 with the second bonding film are bonded together, the first bonding film 31 and the second bonding film 32 are generated near the surfaces 351 and 352. Bonds that are not terminated (unbonded bonds) recombine directly or while taking in oxygen atoms contained in the atmosphere. Since this recombination occurs in a complicated manner so as to overlap (entangle) with each other, a network-like bond is formed at the bonding interface. Accordingly, the first metal atom M1 and the second metal atom M2 included in the first bonding film 31 and the second bonding film 32 are bonded to each other directly or via an oxygen atom, whereby the first bonding is performed. The film 31 and the second bonding film 32 are integrated.

The first bonding film 31 and the second bonding film 32 are bonded by the mechanism (i) or (ii) as described above. In the present invention, the second metal atom M2 is further added to the first metal film M1. The melting point is lower than that of the metal atom M1, and in the step [4], the second metal atom M2 contained in the second bonding film 32 is melted in the first bonding film 31 and the second bonding film 32. Until it heats up. Thereby, the adhesive strength of the 1st joining film 31 and the 2nd joining film 32 can be raised more, and the base material 11 with the 1st joining film and the base material 12 with the 2nd joining film are stronger. The joined body 5 joined to the substrate can be obtained.
As described above, the bonding strength between the first bonding film 31 and the second bonding film 32 is further increased by heating the first bonding film 31 and the second bonding film 32 in the step [4]. This is probably due to the following mechanism.

  Here, after the step [3], when the bonding interface where the first bonding film 31 and the second bonding film 32 are bonded to each other is viewed, the surfaces 351 of the two bonding films 31 and 32 that are in contact with each other, Both 352 are considered to be composed of uneven surfaces. Therefore, the bonding between the first bonding film 31 and the second bonding film 32 formed by the mechanism (i) or (ii) described above is formed at the contact point where the surfaces 351 and 352 contact each other. Is done.

In such a state, the first bonding film 31 and the second bonding film 32 bonded to each other on the surfaces 351 and 352 are heated until the second metal atom M2 included in the second bonding film 32 is melted. Then, the melted second metal atom M2 diffuses to the first bonding film 31 side and enters into the first bonding film 31 constituted by the uneven surface. As a result, the contact area between the first bonding film 31 and the second bonding film 32 increases, and thereby the first bonding film 31 and the second bonding film 32 by the mechanism (i) or (ii). It is presumed that the bonding strength between the first bonding film 31 and the second bonding film 32 is further improved since the bonding between the first bonding film 31 and the second bonding film 32 is further formed.
In the case where both the first bonding film 31 and the second bonding film 32 are conductive, the resistance value between the bonding films 31 and 32 is also increased due to the increase in the contact area as described above. It is assumed that it will decline.

Further, the method of melting the second metal atom M2 and increasing the adhesive strength between the first bonding film 31 and the second bonding film 32 in this way is performed by using a vapor phase film forming method as described later. It is suitably applied to the bonding of the formed first bonding film 31 and second bonding film 32.
This is because both the first bonding film 31 and the second bonding film 32 formed by using the vapor deposition method have the metal atoms contained in the organometallic material and a part of the organic substance remaining. Is formed by stacking a plurality of fine particles. Therefore, the first bonding film 31 and the second bonding film 32 configured as described above are melted with the second metal atom M2 to increase the adhesive strength between the first bonding film 31 and the second bonding film 32. If the bonding method of the invention is applied, the contact area between the first bonding film 31 and the second bonding film 32 can be increased more effectively, so the first bonding film 31 and the second bonding film The adhesive strength with 32 will be further improved.
Further, since the melting point of the second bonding film 32 is lowered when the second bonding film 32 has a particle shape, the bonding between the first bonding film 31 and the second bonding film 32 having the particle shape is also performed from this viewpoint. In addition, it is useful to apply the bonding method of the present invention.

  Further, in the bonding between the first bonding film 31 and the second bonding film 32, different metal atoms are used for the first metal atom M1 and the second metal atom M2, so there is a difference in their ionization tendency. As a result, the difference in standard electrode potential between the first metal atom M1 and the second metal atom M2 is preferably 3.0 mV or more, more preferably 5.0 mV or more. Is more preferable.

  Here, even if the first bonding film 31 and the second bonding film 32 are bonded by any of the mechanisms (i) and (ii) as described above, The contained metal atoms may be bonded through oxygen atoms. Such bonding between metal atoms was performed between the first metal atom M1 included in the first bonding film 31 and the second metal atom M2 included in the second bonding film 32. Sometimes, it contributes to the bonding between the first bonding film 31 and the second bonding film 32, but when it is performed between the metal atoms M 1 and M 2 included in each bonding film 31, 32, This does not contribute to the bonding between the bonding film 31 and the second bonding film 32.

  Therefore, in order to improve the adhesive strength (bonding strength) between the first bonding film 31 and the second bonding film 32, the first metal atom M1 and the second metal atom M2 are bonded via an oxygen atom. In the present invention, different metal atoms are used as the metal atoms contained in the first bonding film 31 and the second bonding film 32, and the first metal atoms M1 and the second metal atoms are separated from each other. A difference is caused in the ionization tendency of the metal atom M2.

If there is such a difference in ionization tendency, the second metal atom M2 can act as a reducing agent for the first metal atom M1, so that the first metal atoms M1 are bonded to each other via an oxygen atom. Thus, oxygen atoms can be extracted from the first metal atoms M1 and the bonds between the first metal atoms M1 and the second metal atoms M2 via the oxygen atoms can be formed preferentially, whereby the first bonding film 31 can be formed. The bonding strength between the second bonding film 32 and the second bonding film 32 can be improved.
Examples of the combination of the first metal atom M1 and the second metal atom M2 include a combination of Cu and In, a combination of Cu and Se, a combination of Cu and Sn, and the like.

Further, in the case where conductivity is imparted to the first bonding film 31 and the second bonding film 32, the second metal atom M2 exhibits conductivity in both an oxidized state and a non-oxidized state. Is preferred. As a result, both the non-oxidized state of the second metal atom M2 and the oxidized state (oxide) acting as a reducing agent exhibit conductivity, so that the oxide exhibits non-conductivity. Compared with the case where the second metal atom M2 is used, the first bonding film 31 and the second bonding film 32 (particularly, the second bonding film 32) can impart superior conductivity.
Examples of the second metal atom M2 include In, Zn, and Sn.

  Further, as described above, the leaving group 303 is desorbed from the first bonding film 31 and the second bonding film 32, so that the first bonding film 31 and the second bonding film 32 are activated. It behaves like generating. Accordingly, the energy is applied to the leaving group 303 relatively easily and uniformly, but when the energy is not applied, the first bonding film 31 and the second bonding film 303 are prevented from being detached. Those that are securely bonded to the bonding film 32 are preferably selected.

  Specifically, as the leaving group 303, an atomic group containing a carbon atom as an essential component and containing at least one of a hydrogen atom, a nitrogen atom, a phosphorus atom, a sulfur atom and a halogen atom is suitably selected. Such a leaving group 303 is relatively excellent in bond / elimination selectivity by energy application. For this reason, such a leaving group 303 can sufficiently satisfy the above-described necessity, and the adhesiveness of the first substrate with a bonding film 11 and the second substrate with a bonding film 12 can be improved. It can be more advanced.

More specifically, examples of the atomic group (group) include an alkyl group such as a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, and a carboxyl group, and the end of the alkyl group is an isocyanate group. And those terminated with a group, an amino group, a sulfonic acid group, and the like.
Among the atomic groups as described above, the leaving group 303 is particularly preferably one containing an alkyl group. Since the leaving group 303 containing an alkyl group has high chemical stability, the first bonding film 31 and the second bonding film 32 each having an alkyl group as the leaving group 303 have weather resistance and chemical resistance. It will be excellent.

  In the first bonding film 31 and the second bonding film 32 having such a configuration, the abundance ratio of metal atoms and carbon atoms contained in each is preferably about 3: 7 to 7: 3. : It is more preferable that it is about 6-6: 4. By setting the abundance ratio of metal atoms and carbon atoms to be within the above range, the stability of the first bonding film 31 and the second bonding film 32 is increased, and the first substrate 11 with bonding film and It becomes possible to join the base material 12 with the second bonding film more firmly. Further, the first bonding film 31 and the second bonding film 32 can exhibit excellent conductivity.

Further, the average thickness of the first bonding film 31 and the second bonding film 32 is preferably about 1 to 1000 nm, and more preferably about 50 to 800 nm. Bonding in which the average thickness of the first bonding film 31 and the second bonding film 32 is within the above range to bond the first substrate 11 with the bonding film and the second substrate 12 with the bonding film. These can be joined more firmly while preventing the dimensional accuracy of the body 5 from being significantly lowered.
That is, when the average thickness of the first bonding film 31 and the second bonding film 32 is less than the lower limit value, sufficient bonding strength may not be obtained. On the other hand, when the average thickness of the first bonding film 31 and the second bonding film 32 exceeds the upper limit, the dimensional accuracy of the bonded body 5 may be significantly reduced.

  The first bonding film 31 and the second bonding film 32 described above may be formed by any method. For example, a leaving group (organic) is formed on a metal film composed of I: metal atoms. Component) The organic substance containing 303 is applied to almost the entire metal film to form the first bonding film 31 and the second bonding film 32, II: a leaving group on the metal film composed of metal atoms (Organic component) 303 is a method of selectively providing (chemically modifying) an organic substance near the surface of the metal film to form the first bonding film 31 and the second bonding film 32, III: a metal atom, Examples thereof include a method of forming the first bonding film 31 and the second bonding film 32 by using a vapor phase film forming method using an organometallic material having an organic substance including a leaving group (organic component) 303 as a raw material. Among these, it is preferable to form the first bonding film 31 and the second bonding film 32 by the method III. According to such a method, it is possible to form the first bonding film 31 and the second bonding film 32 with a uniform film thickness in a relatively simple process.

Hereinafter, the first bonding film 31 and the second bonding are performed by the vapor deposition method using the method III, that is, an organic metal material having a metal atom and an organic substance containing a leaving group (organic component) 303 as a raw material. A method for forming the film 32 will be described as a representative.
In addition to the metal organic chemical vapor deposition method, a physical vapor deposition method such as a vacuum deposition method or a sputtering method can be used as the vapor deposition method. Since the leaving group 303 can be left relatively easily from the organic substance contained in the organometallic material, the organometallic chemical vapor deposition method will be used hereinafter.
In the formation of the first bonding film 31 and the second bonding film 32, only the types of metal atoms contained in the organometallic material used as a raw material are different, that is, the first metal atoms M1 and the second bonding films 32 are formed. Since the only difference is that each of the organometallic materials containing the metal atom M2 is used, the first bonding film 31 is formed below.

First, prior to describing the method of forming the first bonding film 31, the film forming apparatus 200 used when forming the first bonding film 31 will be described.
FIG. 5 is a longitudinal sectional view schematically showing a film forming apparatus used in the bonding method of the present invention. In the following description, the upper side in FIG. 5 is referred to as “upper” and the lower side is referred to as “lower”.
The film forming apparatus 200 shown in FIG. 5 is configured so that the first bonding film 31 can be formed in the chamber 211 by a metal organic chemical vapor deposition method (hereinafter sometimes abbreviated as “MOCVD method”). Has been.

  Specifically, the film forming apparatus 200 includes a chamber (vacuum chamber) 211 and a substrate holder (film forming object holding unit) that is installed in the chamber 211 and holds the first substrate 21 (film forming object). ) 212, an organometallic material supplying means 260 for supplying a vaporized or atomized organometallic material into the chamber 211, and a gas supplying means 270 for supplying a gas for making the inside of the chamber 211 under a low reducing atmosphere , An exhaust means 230 for exhausting the chamber 211 and controlling the pressure, and a heating means (not shown) for heating the substrate holder 212.

The substrate holder 212 is attached to the bottom of the chamber 211 in this embodiment. The substrate holder 212 can be rotated by the operation of a motor. As a result, the first bonding film 31 can be formed on the first substrate 21 with a uniform and uniform thickness.
Further, in the vicinity of the substrate holder 212, a shutter 221 that can cover them is provided. The shutter 221 is for preventing the first substrate 21 and the first bonding film 31 from being exposed to an unnecessary atmosphere or the like.

The organometallic material supply unit 260 is connected to the chamber 211. The organometallic material supply means 260 includes a storage tank 262 that stores a solid organometallic material, a gas cylinder 265 that stores a carrier gas that feeds the vaporized or atomized organometallic material into the chamber 211, and a carrier gas. And a gas supply line 261 for introducing the vaporized or atomized organometallic material into the chamber 211, and a pump 264 and a valve 263 provided in the middle of the gas supply line 261. In the organometallic material supply means 260 having such a configuration, the storage tank 262 has a heating means, and the operation of the heating means can heat and vaporize the solid organometallic material. Therefore, when the pump 264 is operated with the valve 263 opened and the carrier gas is supplied from the gas cylinder 265 to the storage tank 262, the organometallic material vaporized or atomized together with the carrier gas passes through the supply line 261. Then, it is supplied into the chamber 211.
In addition, it does not specifically limit as carrier gas, For example, nitrogen gas, argon gas, helium gas, etc. are used suitably.

In this embodiment, the gas supply unit 270 is connected to the chamber 211. The gas supply means 270 includes a gas cylinder 275 for storing a gas for making the inside of the chamber 211 under a low reducing atmosphere, a gas supply line 271 for guiding the gas for making the low reducing atmosphere into the chamber 211, A pump 274 and a valve 273 are provided in the middle of the gas supply line 271. In the gas supply unit 270 having such a configuration, when the pump 274 is operated with the valve 273 opened, the gas for making the low reducing atmosphere is supplied from the gas cylinder 275 through the supply line 271 to the chamber 211. It is designed to be supplied inside. With such a configuration of the gas supply unit 270, the inside of the chamber 211 can be surely set in a low reduction atmosphere with respect to the organometallic material. As a result, when the first bonding film 31 is formed using the MOCVD method using the organometallic material as a raw material, at least a part of the organic component contained in the organometallic material is left as the leaving group 303. A first bonding film 31 is formed.
The gas for bringing the inside of the chamber 211 into a low reducing atmosphere is not particularly limited, and examples thereof include nitrogen gas and rare gases such as helium, argon, and xenon. A combination of more than one species can be used.

In addition, as organometallic materials, 2,4-pentadionate-copper (II) and [Cu (hfac) (VTMS)], bis (dipivaloylmethanite) copper [Cu (DPM) ₂ ], bis described below, are used. (Dipivaloylmethanite) When using a compound containing an oxygen atom in a molecular structure such as a β-diketone complex having a β-diketone as a ligand such as indium [In (DPM) ₂ ], It is preferable to add hydrogen gas to the gas for achieving a low reducing atmosphere. Thereby, the reducibility with respect to oxygen atoms can be improved, and the first bonding film 31 can be formed without excessive oxygen atoms remaining in the first bonding film 31. As a result, the first bonding film 31 has a low abundance of metal oxide in the film and exhibits excellent conductivity.

In addition, when at least one of the nitrogen gas, argon gas and helium gas described above is used as the carrier gas, the carrier gas can also exhibit a function as a gas for providing a low reducing atmosphere. it can.
The exhaust means 230 includes a pump 232, an exhaust line 231 that communicates the pump 232 and the chamber 211, and a valve 233 provided in the middle of the exhaust line 231. The pressure can be reduced.

The first bonding film 31 is formed on the first substrate 21 by the MOCVD method using the film forming apparatus 200 configured as described above.
[1] First, the first substrate 21 is prepared. Then, the first substrate 21 is carried into the chamber 211 of the film forming apparatus 200 and mounted (set) on the substrate holder 212.

[2] Next, the exhaust means 230 is operated, that is, the valve 233 is opened while the pump 232 is operated, so that the inside of the chamber 211 is decompressed. The degree of vacuum (degree of vacuum) is not particularly limited, but is preferably about 1 × 10 ⁻⁷ to 1 × 10 ⁻⁴ Torr, preferably about 1 × 10 ⁻⁶ to 1 × 10 ⁻⁵ Torr. Is more preferable.
Further, the gas supply means 270 is operated, that is, the valve 273 is opened while the pump 274 is operated, so that a gas for making a low reducing atmosphere is supplied into the chamber 211, Under a low reducing atmosphere. The flow rate of the gas by the gas supply means 270 is not particularly limited, but is preferably about 0.1 to 10 sccm, and more preferably about 0.5 to 5 sccm.

  Further, at this time, the heating means is operated to heat the substrate holder 212. The temperature of the substrate holder 212 is slightly different depending on the type of the first bonding film 31 to be formed, that is, the type of raw material used when forming the first bonding film 31, but is about 80 to 300 ° C. Preferably, it is about 100-275 degreeC. By setting within this range, the first bonding film 31 having excellent adhesiveness can be formed using an organometallic material described later.

[3] Next, the shutter 221 is opened.
Then, by operating the heating means provided in the storage tank 262 in which the solid organic metal material is stored, the pump 264 is operated while the organic metal material is vaporized, and the valve 263 is opened to vaporize. Alternatively, the atomized organometallic material is introduced into the chamber together with the carrier gas.

  As described above, when the organometallic material containing the first metal atom M1 as the metal atom is supplied into the chamber 211 in a state where the substrate holder 212 is heated in the step [2], the first substrate 21 is heated. By heating the organometallic material, the first bonding film 31 can be formed on the first substrate 21 in a state where a part of the organic substance contained in the organometallic material remains.

That is, according to the MOCVD method, if a film containing metal atoms is formed so that a part of the organic substance contained in the organometallic material remains, a part of the organic substance exhibits a function as the leaving group 303. One bonding film 31 can be formed on the first substrate 21.
Note that the first bonding film 31 formed using the MOCVD method includes the first metal atoms M1 and the second metal atoms included in the organometallic material in which the first organometallic material and the second organometallic material are mixed. Since the metal atom M2 and the one in which a part of the organic substance remains are deposited, it can be considered as a stacked body in which a plurality of fine particles are stacked.

The organometallic material used in such MOCVD method is not particularly limited. For example, bis (2,6-dimethyl-2- (trimethylsilyloxy) -3,5-heptadionato) copper (II) (Cu (SOPD) ₂ ; C ₂₄ H ₄₆ CuO ₆ Si ₂ ), 2,4-pentadionate-copper (II), Cu (hexafluoroacetylacetonate) (vinyltrimethylsilane) [Cu (hfac) (VTMS)] Cu (hexafluoroacetylacetonate) (2-methyl-1-hexen-3-ene) [Cu (hfac) (MHY)], Cu (perfluoroacetylacetonate) (vinyltrimethylsilane) [Cu (pfac) (VTMS)], Cu (perfluoroacetylacetonate) (2-methyl-1-hexen-3-ene) [Cu ( fac) (MHy)], bis (di-pivaloyl meth night) copper _{[Cu (DPM) 2, DMP} : C 11 H 19 O 2], bis (di-pivaloyl meth night) indium [In _(DPM) 2], Tris (dipivaloylmethanite) aluminum [Al (DPM) ₃ ], di (dipivaloylmethanite) lead [Pb (DPM) ₂ ], tris (dipivaloylmethanite) iron [Fe (DPM) ₃ ] Bis (isobutylpivaloylmethanite) copper [Cu (IBPM) ₂ , IBMP: C ₁₀ H ₁₇ O ₂ ] tris (isobutylpivaloylmethanite) ruthenium [Ru (IBPM) ₃ ], bis (diisobutyrylmethanite) copper _{[Cu (DIBM) 2, DIBM} : C 9 H 15 O 2] β -diketone complex comprising a beta-diketone such as a ligand, tri (8-quinolinolato) aluminum _(Alq 3), tris (4-methyl-8-quinolinolato) aluminum (III) (Almq _3), (8-hydroxyquinoline) quinolinol complexes such as zinc (Znq _2), copper phthalocyanine Metal complexes such as phthalocyanine complexes such as copper trifluoroacetate, yttrium trifluoroacetate, and carboxylate complexes such as copper terephthalate complex, alkyl metals such as trimethylgallium, trimethylaluminum, and diethylzinc, and derivatives thereof Etc. Among these, the organometallic material is preferably a metal complex. By using the metal complex, the first bonding film 31 can be reliably formed in a state in which a part of the organic substance contained in the metal complex is left. Among metal complexes, a β-diketone complex is particularly preferable. By using a β-diketone complex, the above-mentioned effect can be recognized more remarkably. In addition, β-diketone complexes are stable with low reactivity compared to metal complexes in which oxygen atoms are coordinated to metal atoms, and atoms other than oxygen atoms are coordinated to metal atoms such as carbon atoms. And easy to handle.
The organometallic material as described above is selected according to the type of the first bonding film 31 to be formed, that is, according to the types of the first metal atom M1 and the leaving group 303.

Further, in this embodiment, the gas supply means 270 is operated so that the inside of the chamber 211 is in a low reducing atmosphere. By making such an atmosphere, pure gas is formed on the first substrate 21. Without forming a metal film, it is possible to form a film in a state where a part of the organic substance contained in the organometallic material remains. That is, the first bonding film 31 having excellent characteristics as both the bonding film and the metal film can be formed.
The flow rate of the vaporized or atomized organometallic material is preferably about 0.1 to 100 ccm, and more preferably about 0.5 to 60 ccm. Accordingly, the first bonding film 31 can be formed with a uniform film thickness and with a part of the organic substance contained in the organometallic material remaining.

As described above, it is necessary to introduce a leaving group into the formed metal film or the like by using the residue remaining in the film as the leaving group 303 when the first bonding film 31 is formed. Therefore, the first bonding film 31 can be formed by a relatively simple process.
Note that a part of the organic substance remaining in the first bonding film 31 formed using an organometallic material may function as the leaving group 303, or a part of the organic substance may be removed. It may function as the leaving group 303.

As described above, the first bonding film 31 is formed on the first substrate 21 to obtain the first substrate 11 with the bonding film.
In the case where the second bonding film 32 is formed on the second substrate 22, the organic metal material contains the second metal atom M2 instead of the one containing the first metal atom M1. A film can be formed using the MOCVD method as described above.

  In the present embodiment, the metal atom contained in the first bonding film 31 is composed of the first metal atom M1, and the metal atom contained in the second bonding film 32 is the second metal atom. Although the case where M2 is configured has been described, the present invention is not limited thereto, and when the metal atom included in the first bonding film 31 is configured by the first metal atom M1, the second bonding film 32 includes: The first metal atom M1 may be included in addition to the second metal atom M2, and conversely, the metal atom included in the second bonding film 32 is configured by the second metal atom M2. In this case, the first bonding film 31 may include a second metal atom M2 in addition to the first metal atom M1.

<< Second Embodiment >>
Next, a second embodiment of the joining method of the present invention will be described.
7 and 8 are views (longitudinal sectional views) for explaining a second embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 7 and 8 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the bonding method according to the second embodiment will be described, but the description will focus on differences from the first embodiment, and description of similar matters will be omitted.
In the bonding method according to the present embodiment, energy is applied to the first bonding film 31 and the second bonding film 32 after the first substrate 11 with the bonding film and the second substrate 12 with the bonding film are overlapped. Is the same as that of the first embodiment except that.

  That is, in the bonding method according to the present embodiment, the first bonding film including the first metal atom and the leaving group composed of the organic component is formed on the first base material to form the first bonding film. A second substrate containing a bonding film-attached substrate and comprising a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component on the second substrate. Forming the bonding film to obtain the second substrate with the bonding film, and the first bonding film-coated substrate and the first bonding film so that the first bonding film and the second bonding film are in close contact with each other. A step of obtaining a laminate by superimposing a second substrate with a bonding film, and applying energy to the first bonding film and the second bonding film, the first bonding film and By removing the leaving group present near the surface of the second bonding film from the bonding film, the first bonding film and The step of obtaining adhesiveness in the second bonding film to obtain a bonded body in which the first bonding film and the second bonding film are bonded; the first bonding film and the second bonding film; Heating the bonding film until the second metal atoms are melted, thereby improving the bonding strength of the bonded body.

Hereinafter, each process of the joining method concerning this embodiment is demonstrated one by one.
[1] First, in the same manner as in the first embodiment, a first base material 11 with a bonding film and a second base material 12 with a bonding film are obtained (see FIG. 7A).
[2] Next, as shown in FIG. 7 (b), the first substrate 11 with the bonding film and the second bonding so that the first bonding film 31 and the second bonding film 32 are in close contact with each other. The laminated body 51 is obtained by superimposing the substrate 12 with a film.
Note that, in the state of the laminated body 51, the first base material 11 with the bonding film (first bonding film 31) and the second base material 12 with the bonding film (second bonding film 32) are bonded. Since it is not carried out, the relative position of the substrate 11 with the first bonding film relative to the substrate 12 with the second bonding film can be adjusted. Thereby, after the 1st base material 11 with a bonding film and the 2nd base material 12 with a bonding film were piled up, these positions can be finely adjusted easily. As a result, the positional accuracy of the first bonding film 31 and the second bonding film 32 in the directions of the surfaces 351 and 352 can be increased.

[3] Next, as shown in FIG. 7C, energy is applied to the first bonding film 31 and the second bonding film 32 in the stacked body 51. When energy is applied to the first bonding film 31 and the second bonding film 32, the first bonding film 31 exhibits adhesiveness with the second substrate 12 with the bonding film, and the second bonding film The adhesiveness with the base material 11 with the 1st bonding film expresses to 32. Thereby, the base material 11 with the 1st joining film and the base material 12 with the 2nd joining film are joined, and the joined body 5 as shown in FIG.7 (d) is obtained.
Here, the energy applied to the first bonding film 31 and the second bonding film 32 may be applied by any method. For example, the energy may be applied by the method described in the first embodiment.

  Further, in the present embodiment, as a method for applying energy to the first bonding film 31 and the second bonding film 32, in particular, the first bonding film 31 and the second bonding film 32 are irradiated with energy rays. It is preferable to use at least one of a method, a heating method, and a compressive force (physical energy). Since these methods can apply energy to the first bonding film 31 and the second bonding film 32 relatively easily and efficiently, these methods are suitable as energy applying methods.

Among these, as a method of irradiating the first bonding film 31 and the second bonding film 32 with energy rays, the same method as in the first embodiment can be used.
In this case, the energy rays pass through the first substrate 21 or the second substrate 22 and are irradiated to the first bonding film 31 and the second bonding film 32. Therefore, the substrate on the side irradiated with the energy beam out of the first substrate 21 or the second substrate 22 is configured to have a light-transmitting property.

  On the other hand, when energy is applied to the first bonding film 31 and the second bonding film 32 by heating the first bonding film 31 and the second bonding film 32, the temperature for heating them is Although it is set below the melting point of the second metal atom M2 (second bonding film 32), specifically, the heating temperature is preferably about 25 to 100 ° C., although it varies depending on the type of the second metal atom M2. More preferably, it is set to about 50 to 80 ° C. Heating at a temperature in such a range reliably prevents the first bonding film 31 and the second bonding film 32 from being in a molten state, and the substrates 21 and 22 from being altered or deteriorated by heat. The first bonding film 31 and the second bonding film 32 can be reliably activated.

The heating time is preferably set to a time that allows the leaving groups 303 of the first bonding film 31 and the second bonding film 32 to be released. Specifically, the heating temperature is within the above range. For example, it is preferably about 1 to 30 minutes.
The first bonding film 31 and the second bonding film 32 may be heated by any method. For example, the first bonding film 31 and the second bonding film 32 may be heated by various methods such as a method using a heater, a method of irradiating infrared rays, and a method of contacting with a flame. Can be heated.
Note that in the case of using a method of irradiating infrared rays, the first substrate 21 or the second substrate 22 is preferably made of a light-absorbing material. Thereby, the 1st board | substrate 21 or the 2nd board | substrate 22 irradiated with infrared rays generate | occur | produces heat | fever efficiently. As a result, the first bonding film 31 and the second bonding film 32 can be efficiently heated.

  Further, when using a method using a heater or a method of contacting with a flame, the substrate on the side of the first substrate 21 or the second substrate 22 that contacts the heater or the flame is made of a material having excellent thermal conductivity. Preferably, it is configured. Accordingly, heat can be efficiently transferred to the first bonding film 31 and the second bonding film 32 via the first substrate 21 or the second substrate 22, and the first bonding film 31 and The second bonding film 32 can be efficiently heated.

Further, when energy is applied to the first bonding film 31 and the second bonding film 32 by applying a compressive force to the first bonding film 31 and the second bonding film 32, It is preferable to compress at a pressure of about 0.2 to 10 MPa, and to compress at a pressure of about 1 to 5 MPa in a direction in which the base material 11 with the bonding film and the second base material 12 with the bonding film approach each other. More preferred. Accordingly, it is possible to easily apply appropriate energy to the first bonding film 31 and the second bonding film 32 by simply compressing the first bonding film 31 and the second bonding film 32. In addition, sufficient adhesion to these films appears. The pressure may exceed the upper limit, but depending on the constituent materials of the first substrate 21 and the second substrate 22, the first substrate 21 and the second substrate 22 may be damaged. There is a fear.
The time for applying the compressive force is not particularly limited, but is preferably about 10 seconds to 30 minutes. In addition, what is necessary is just to change suitably the time which provides compression force according to the magnitude | size of compression force. Specifically, the time for applying the compressive force can be shortened as the compressive force increases.

[4] Next, in the same manner as in the first embodiment, as shown in FIG. 8A, until the second metal atom M2 is melted in the first bonding film 31 and the second bonding film 32. Heat.
As a result, the second metal atoms M2 contained in the second bonding film 32 are diffused to the first bonding film 31 side. As a result, the first bonding film 31 and the first bonding film 31 as shown in FIG. A bonded body 5 with improved bonding strength with the second bonding film 32 can be obtained.
The bonded body 5 can be obtained as described above.
In addition, after obtaining the joined body 5, at least one of the steps [5A] and [5B] of the first embodiment may be performed on the joined body 5 as necessary. .

<< Third Embodiment >>
Next, a third embodiment of the joined method of the joined body of the present invention will be described.
9 and 10 are views (longitudinal sectional views) for explaining a third embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 9 and 10 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the bonding method according to the third embodiment will be described, but the description will focus on differences from the first embodiment to the third embodiment, and description of similar matters will be omitted.
In the bonding method according to the present embodiment, the first bonding film 31 and the second bonding film 32 are selectively formed only in some predetermined regions 350 of the upper surfaces 251 and 252 of the substrates 21 and 22. Thus, the first embodiment is the same as the first embodiment except that the first substrate 11 with a bonding film and the second substrate 12 with a bonding film are partially bonded in the predetermined region 350.

  That is, in the bonding method according to the present embodiment, the first bonding film including the first metal atom and the leaving group composed of the organic component is formed in a partial region on the first substrate. Thus, the first substrate with the bonding film is obtained, and the second metal atom having a melting point lower than that of the first metal atom and an organic component are formed in a part of the region on the second substrate. Forming a second bonding film containing a leaving group to obtain a second substrate with a bonding film, applying energy to the first bonding film and the second bonding film, By removing the leaving group existing near the surfaces of the first bonding film and the second bonding film from these bonding films, the first bonding film and the second bonding film can be made adhesive. The substrate with the first bonding film and the front so that the first bonding film and the second bonding film are in close contact with each other A step of obtaining a bonded body obtained by bonding the second base material with the bonding film and partially bonding them in a partial region, the first bonding film and the second bonding film, And heating the two metal atoms until they are melted to improve the bonding strength of the bonded body.

Hereinafter, each process of the joining method concerning this embodiment is demonstrated one by one.
[1] First, as shown in FIG. 9A, the mask 6 having the window 61 corresponding to the shape of the predetermined region 350 is disposed above each of the substrates 21 and 22.
Next, the first bonding film 31 and the second bonding film 32 are formed on the upper surfaces 251 and 252 of the first substrate 21 and the second substrate 22 through the mask 6, respectively. For example, as shown in FIG. 9A, when the first bonding film 31 and the second bonding film 32 are formed through the mask 6, for example, using the MOCVD method described in the first embodiment. The organic metal material is deposited on the upper surfaces 251 and 252 of the respective substrates 21 and 22 in a state in which a part of the organic substances contained in the organic metal material remains, and at this time, each predetermined region is obtained through the mask 6. A part of the organometallic material is deposited only on 350. As a result, the first bonding film 31 and the second bonding film 32 are formed in some predetermined regions 350 of the upper surfaces 251 and 252 of the substrates 21 and 22, respectively.

[2] Next, as shown in FIG. 9B, energy is applied to the first bonding film 31 and the second bonding film 32. Thereby, in each base material 11 and 12 with a joining film, adhesiveness expresses in the 1st joining film 31 and the 2nd joining film 32.
Note that when energy is applied in this step, energy may be selectively applied to the first bonding film 31 and the second bonding film 32, but the first bonding film 31 and the second bonding film may be used. Energy may be applied to the entire upper surfaces 251 and 252 of the substrates 21 and 22 including the film 32, respectively.
In addition, the energy applied to the first bonding film 31 and the second bonding film 32 may be applied by any method, for example, the method described in the first embodiment.

[3] Next, as shown in FIG. 9C, the two substrates 11 with the bonding film are provided so that the first bonding film 31 and the second bonding film 32 exhibiting adhesiveness are in close contact with each other. , 12 are pasted together. Thereby, the joined body 5b as shown in FIG.9 (d) can be obtained.
The joined body 5b obtained in this way does not join the two substrates 11 and 12 with the bonding film over the entire opposing surface, but partially joins only a part of the region (predetermined region 350). It is made. The region to be bonded can be easily selected only by controlling the film formation regions of the bonding films 31 and 32 on the substrates 21 and 22. Thereby, for example, the bonding strength of the bonded body 5b can be easily adjusted.

  Further, a gap 3c having a separation distance corresponding to the total thickness of the first bonding film 31 and the second bonding film 32 is formed between the substrates 21 and 22 of the bonded body 5b in a region other than the predetermined region 350. (See FIG. 9D). Accordingly, by appropriately adjusting the shape of the predetermined region 350 and the thicknesses of the bonding films 31 and 32, a closed space or a flow path having a desired shape can be easily formed between the substrates 21 and 22. .

[4] Next, in the same manner as in the first embodiment, as shown in FIG. 10A, until the second metal atom M2 is melted in the first bonding film 31 and the second bonding film 32. Heat.
As a result, the second metal atoms M2 contained in the second bonding film 32 are diffused to the first bonding film 31 side. As a result, the first bonding film 31 and the first bonding film 31 as shown in FIG. The bonded body 5b having a further improved bonding strength with the second bonding film 32 can be selectively formed in the predetermined region 350.

The bonded body 5b can be obtained as described above.
After obtaining the joined body 5b, at least one of the steps [5A] and [5B] of the first embodiment may be performed on the joined body 5b as necessary. .
For example, energy rays are applied when the substrates 21 and 22 of the joined body 5b come closer to each other by irradiating energy beams while pressurizing the joined body 5b. Thereby, dehydration condensation of hydroxyl groups and recombination of dangling bonds at the interface between the first bonding film 31 and the second bonding film 32 are promoted. Then, the integration proceeds further at the joint formed in the predetermined region 350, and finally, it is almost completely integrated.

  In the present embodiment, the first bonding film 31 and the second bonding film 32 formed in a part of the first substrate 21 and the partial region (predetermined region 350) on the second substrate 22 are the same. Although the case of forming the shape has been described, the present invention is not limited to this case, and the shapes of the first bonding film 31 and the second bonding film 32 may be different from each other. In this case, in a plan view, the first bonding film 31 and the second bonding film 32 are bonded to each other in a region where they overlap each other.

The joining method according to each of the embodiments as described above can be used to join various members.
Examples of members used for such bonding include semiconductor elements such as transistors, diodes, and memories, piezoelectric elements such as crystal oscillators, optical elements such as reflectors, optical lenses, diffraction gratings, and optical filters. , Photoelectric conversion elements such as solar cells, semiconductor substrates and semiconductor elements mounted thereon, insulating substrates and wiring or electrodes, inkjet recording heads, microreactors, microelectromechanical system (MEMS) components such as micromirrors, pressure Sensor parts such as sensors, acceleration sensors, package parts for semiconductor elements and electronic parts, magnetic recording media, magneto-optical recording media, recording media such as optical recording media, liquid crystal display elements, organic EL elements, electrophoretic display elements Such display element parts, fuel cell parts, and the like.

<Droplet ejection head>
Here, an embodiment in which the joined body of the present invention is applied to an ink jet recording head will be described.
FIG. 11 is an exploded perspective view showing an ink jet recording head (droplet discharge head) obtained by applying the joined body of the present invention, and FIG. 12 shows the configuration of the main part of the ink jet recording head shown in FIG. FIG. 13 is a schematic view showing an embodiment of an ink jet printer including the ink jet recording head shown in FIG. In addition, FIG. 11 is shown upside down from the state normally used.

An ink jet recording head 10 shown in FIG. 11 is mounted on an ink jet printer 9 as shown in FIG.
An ink jet printer 9 shown in FIG. 13 includes an apparatus main body 92, a tray 921 in which the recording paper P is installed at the upper rear, a paper discharge port 922 for discharging the recording paper P in the lower front, and an operation panel on the upper surface. 97.
The operation panel 97 includes, for example, a liquid crystal display, an organic EL display, an LED lamp, and the like, and a display unit (not shown) for displaying an error message and the like, and an operation unit (not shown) configured with various switches and the like. And.

Further, inside the apparatus main body 92, mainly a printing apparatus (printing means) 94 provided with a reciprocating head unit 93 and a paper feeding apparatus (paper feeding means) for feeding recording paper P to the printing apparatus 94 one by one. 95 and a control unit (control means) 96 for controlling the printing device 94 and the paper feeding device 95.
Under the control of the control unit 96, the paper feeding device 95 intermittently feeds the recording paper P one by one. The recording paper P passes near the lower part of the head unit 93. At this time, the head unit 93 reciprocates in a direction substantially orthogonal to the feeding direction of the recording paper P, and printing on the recording paper P is performed. That is, the reciprocating motion of the head unit 93 and the intermittent feeding of the recording paper P become the main scanning and sub-scanning in printing, and ink jet printing is performed.

The printing apparatus 94 includes a head unit 93, a carriage motor 941 that is a drive source of the head unit 93, and a reciprocating mechanism 942 that reciprocates the head unit 93 in response to the rotation of the carriage motor 941.
The head unit 93 includes an ink jet recording head 10 (hereinafter simply referred to as “head 10”) having a large number of nozzle holes 111 at a lower portion thereof, an ink cartridge 931 that supplies ink to the head 10, the head 10 and And a carriage 932 on which the ink cartridge 931 is mounted.
Ink cartridge 931 is filled with four color inks of yellow, cyan, magenta, and black (black), thereby enabling full color printing.

The reciprocating mechanism 942 includes a carriage guide shaft 943 whose both ends are supported by a frame (not shown), and a timing belt 944 extending in parallel with the carriage guide shaft 943.
The carriage 932 is supported by the carriage guide shaft 943 so as to be able to reciprocate and is fixed to a part of the timing belt 944.
When the timing belt 944 travels forward and backward via a pulley by the operation of the carriage motor 941, the head unit 93 reciprocates as guided by the carriage guide shaft 943. During this reciprocation, ink is appropriately discharged from the head 10 and printing on the recording paper P is performed.

The sheet feeding device 95 includes a sheet feeding motor 951 serving as a driving source thereof, and a sheet feeding roller 952 that is rotated by the operation of the sheet feeding motor 951.
The paper feed roller 952 includes a driven roller 952a and a drive roller 952b that are vertically opposed to each other with a feeding path (recording paper P) of the recording paper P interposed therebetween. The drive roller 952b is connected to the paper feed motor 951. As a result, the paper feed roller 952 can feed a large number of recording sheets P set on the tray 921 one by one toward the printing apparatus 94. Instead of the tray 921, a configuration in which a paper feed cassette that stores the recording paper P can be detachably mounted may be employed.

The control unit 96 performs printing by controlling the printing device 94, the paper feeding device 95, and the like based on print data input from a host computer such as a personal computer or a digital camera.
Although not shown, the control unit 96 mainly includes a memory that stores a control program for controlling each unit, a piezoelectric element driving circuit that drives the piezoelectric element (vibration source) 14 to control the ink ejection timing, A driving circuit for driving the printing device 94 (carriage motor 941), a driving circuit for driving the paper feeding device 95 (paper feeding motor 951), a communication circuit for obtaining print data from the host computer, and these electrically And a CPU that is connected and performs various controls in each unit.
Further, for example, various sensors that can detect the remaining ink amount of the ink cartridge 931, the position of the head unit 93, and the like are electrically connected to the CPU.

  The control unit 96 obtains print data via the communication circuit and stores it in the memory. The CPU processes the print data and outputs a drive signal to each drive circuit based on the process data and input data from various sensors. The piezoelectric element 14, the printing device 94, and the paper feeding device 95 are each activated by this drive signal. As a result, printing is performed on the recording paper P.

Hereinafter, the head 10 will be described in detail with reference to FIGS. 11 and 12.
The head 10 includes a head main body 17 including a nozzle plate 110, an ink chamber substrate 120, a vibration plate 13, and a piezoelectric element (vibration source) 14 bonded to the vibration plate 13, and a base body that houses the head main body 17. 16. The head 10 constitutes an on-demand piezo jet head.

The nozzle plate 110 is made of, for example, a silicon-based material such as SiO ₂ , SiN, or quartz glass, a metal-based material such as Al, Fe, Ni, Cu, or an alloy containing these, or an oxide-based material such as alumina or iron oxide. The material is composed of carbon-based materials such as carbon black and graphite.
The nozzle plate 110 has a large number of nozzle holes 111 for discharging ink droplets. The pitch between these nozzle holes 111 is appropriately set according to the printing accuracy.

An ink chamber substrate 120 is fixed (fixed) to the nozzle plate 110.
The ink chamber substrate 120 includes a plurality of ink chambers (cavities, pressure chambers) 121 and a reservoir chamber that stores ink supplied from the ink cartridge 931 by a nozzle plate 110, a side wall (partition wall) 122, and a diaphragm 13 described later. 123 and a supply port 124 for supplying ink from the reservoir chamber 123 to each ink chamber 121 are partitioned.
Each ink chamber 121 is formed in a strip shape (cuboid shape), and is disposed corresponding to each nozzle hole 111. Each ink chamber 121 has a variable volume due to vibration of a diaphragm 13 described later, and is configured to eject ink by this volume change.

As a base material for obtaining the ink chamber substrate 120, for example, a silicon single crystal substrate, various glass substrates, various resin substrates, and the like can be used. Since these substrates are general-purpose substrates, the manufacturing cost of the head 10 can be reduced by using these substrates.
On the other hand, the vibration plate 13 is bonded to the side of the ink chamber substrate 120 opposite to the nozzle plate 110, and a plurality of piezoelectric elements 14 are provided on the side of the vibration plate 13 opposite to the ink chamber substrate 120.
A communication hole 131 is formed at a predetermined position of the diaphragm 13 so as to penetrate in the thickness direction of the diaphragm 13. Ink can be supplied from the ink cartridge 931 to the reservoir chamber 123 through the communication hole 131.

Each piezoelectric element 14 has a piezoelectric layer 143 interposed between the lower electrode 142 and the upper electrode 141, and is disposed corresponding to the substantially central portion of each ink chamber 121. Each piezoelectric element 14 is electrically connected to a piezoelectric element drive circuit and is configured to operate (vibrate, deform) based on a signal from the piezoelectric element drive circuit.
Each piezoelectric element 14 functions as a vibration source, and the diaphragm 13 vibrates due to vibration of the piezoelectric element 14 and functions to instantaneously increase the internal pressure of the ink chamber 121.
The base body 16 is made of, for example, various resin materials, various metal materials, and the like, and the nozzle plate 110 is fixed and supported on the base body 16. That is, the edge of the nozzle plate 110 is supported by the step 162 formed on the outer periphery of the recess 161 in a state where the head body 17 is housed in the recess 161 provided in the base body 16.

When the nozzle plate 110 and the ink chamber substrate 120 are bonded as described above, the ink chamber substrate 120 and the vibration plate 13 are bonded, and the nozzle plate 110 and the base body 16 are bonded, at least one place of the present invention is used. A joining method is applied.
In other words, the present invention is provided in at least one place among the joined body of the nozzle plate 110 and the ink chamber substrate 120, the joined body of the ink chamber substrate 120 and the vibration plate 13, and the joined body of the nozzle plate 110 and the substrate 16. The joined body is applied.

Such a head 10 has high bonding strength and chemical resistance at the bonding interface of the bonding portion, and thereby has high durability and liquid tightness with respect to the ink stored in each ink chamber 121. As a result, the head 10 becomes highly reliable.
In addition, since highly reliable bonding can be performed at a very low temperature, it is advantageous in that a large-area head can be formed even with materials having different linear expansion coefficients.

  Such a head 10 is in a state where a predetermined ejection signal is not input via the piezoelectric element driving circuit, that is, in a state where no voltage is applied between the lower electrode 142 and the upper electrode 141 of the piezoelectric element 14. The piezoelectric layer 143 is not deformed. For this reason, the vibration plate 13 is not deformed, and the volume of the ink chamber 121 is not changed. Therefore, no ink droplet is ejected from the nozzle hole 111.

  On the other hand, in a state where a predetermined ejection signal is input via the piezoelectric element driving circuit, that is, in a state where a constant voltage is applied between the lower electrode 142 and the upper electrode 141 of the piezoelectric element 14, the piezoelectric layer 143 is applied. Deformation occurs. As a result, the diaphragm 13 is greatly deflected, and the volume of the ink chamber 121 is changed. At this time, the pressure in the ink chamber 121 increases instantaneously, and ink droplets are ejected from the nozzle holes 111.

  When the ejection of one ink is completed, the piezoelectric element driving circuit stops applying the voltage between the lower electrode 142 and the upper electrode 141. As a result, the piezoelectric element 14 returns almost to its original shape, and the volume of the ink chamber 121 increases. At this time, a pressure (pressure in the positive direction) from the ink cartridge 931 toward the nozzle hole 111 acts on the ink. Therefore, air is prevented from entering the ink chamber 121 from the nozzle hole 111, and an amount of ink corresponding to the amount of ink discharged is supplied from the ink cartridge 931 (reservoir chamber 123) to the ink chamber 121.

In this manner, in the head 10, arbitrary (desired) characters and figures can be printed by sequentially inputting ejection signals to the piezoelectric elements 14 at the positions to be printed via the piezoelectric element driving circuit. it can.
The head 10 may have an electrothermal conversion element instead of the piezoelectric element 14. That is, the head 10 may have a configuration (so-called “bubble jet method” (“bubble jet” is a registered trademark)) that ejects ink using thermal expansion of a material by an electrothermal transducer.

  In the head 10 having such a configuration, the nozzle plate 110 is provided with a coating 114 formed for the purpose of imparting liquid repellency. Thus, when ink droplets are ejected from the nozzle holes 111, it is possible to reliably prevent ink droplets from remaining around the nozzle holes 111. As a result, the ink droplets ejected from the nozzle hole 111 can be reliably landed on the target area.

<Wiring board>
Furthermore, an embodiment when the joined body of the present invention is applied to a wiring board will be described.
FIG. 14 is a perspective view showing a wiring board obtained by applying the joined body of the present invention.
The wiring substrate 410 shown in FIG. 14 includes an insulating substrate 413, an electrode 412 disposed on the insulating substrate 413, a lead 414, and an electrode 415 provided at one end of the lead 414 so as to face the electrode 412. Have

  A first bonding film 31 and a second bonding film 32 are formed on the upper surface of the electrode 412 and the lower surface of the electrode 415, respectively. The first bonding film 31 and the second bonding film 32 are bonded together by bonding using the bonding method of the present invention described above. As a result, the electrodes 412 and 415 are firmly bonded by the integrated first bonding film 31 and second bonding film 32, and delamination between the electrodes 412 and 415 is ensured. In addition to being prevented, a highly reliable wiring board 410 is obtained.

In addition, the first bonding film 31 and the second bonding film 32 are selected by selecting one having conductivity as the first metal atom M1 and the second metal atom M2 included in each of the electrodes 412, It also has a function of conducting between 415. The first bonding film 31 and the second bonding film 32 exhibit a sufficient bonding force even if they are very thin. For this reason, the gap between the electrodes 412, 415 can be made smaller, and the electrical resistance component (contact resistance) between the electrodes 412, 415 can be reduced. As a result, the conductivity between the electrodes 412 and 415 can be further increased.
Further, as described above, the thickness of the first bonding film 31 and the second bonding film 32 can be easily controlled with high accuracy. As a result, the wiring substrate 410 has higher dimensional accuracy, and the conductivity between the electrodes 412 and 415 can be easily controlled.

As mentioned above, although the joining method and joined body of this invention were demonstrated based on embodiment of illustration, this invention is not limited to these.
For example, the joining method of the present invention may be any one or a combination of two or more of the above embodiments.
Moreover, in the joining method of this invention, you may add the process of 1 or more arbitrary objectives as needed.
In each of the above embodiments, the method of joining two base materials of the first substrate and the second substrate is described. However, when three or more base materials are joined, the joining of the present invention is performed. A method and a joined body may be used.

Next, specific examples of the present invention will be described.
1. Manufacture of joined body (Example 1)
First, a single crystal silicon substrate having a length of 20 mm, a width of 20 mm, and an average thickness of 1 mm was prepared as a first substrate, and a glass substrate having a length of 20 mm, a width of 20 mm, and an average thickness of 1 mm was prepared as a second substrate.

Next, the single crystal silicon substrate was accommodated in the chamber 211 of the film formation apparatus 200 illustrated in FIG. 5, and surface treatment with oxygen plasma was performed.
Next, a first bonding film having an average thickness of 100 nm was formed on the surface subjected to the surface treatment by using the raw material Cu (DPM) ₂ and using the MOCVD method. The film forming conditions are as shown below.

<Film formation conditions>
・ Atmosphere in chamber: Nitrogen gas + Hydrogen gas ・ Organic metal material (raw material): Cu (DPM) ₂
・ Flow rate of atomized organometallic material: 2 sccm
・ Carrier gas: Nitrogen gas ・ Flow rate of carrier gas: 250 sccm
・ Hydrogen gas flow rate: 0.2 sccm
-Pressure in the chamber during film formation: 1 × 10 ⁻³ Torr
・ Temperature of substrate holder: 200 ℃
Processing time: 15 minutes The first bonding film formed as described above contains a copper atom as the first metal atom and a part of the organic substance contained in Cu (DPM) ₂ as the leaving group Remains.
Thereby, the base material with the 1st joining film in which the 1st joining film was formed on the single crystal silicon substrate was obtained.

Next, the glass substrate was accommodated in the chamber 211 of the film forming apparatus 200 shown in FIG. 5, and surface treatment with oxygen plasma was performed.
Next, a second bonding film having an average thickness of 100 nm was formed on the surface subjected to the surface treatment using In (DPM) ₂ as a raw material and using the MOCVD method. The film forming conditions are as shown below.

<Film formation conditions>
・ Atmosphere in the chamber: Nitrogen gas + Hydrogen gas ・ Organic metal material (raw material): In (DPM) ₂
・ Flow rate of atomized organometallic material: 2 sccm
・ Carrier gas: Nitrogen gas ・ Flow rate of carrier gas: 250 sccm
・ Hydrogen gas flow rate: 0.2 sccm
-Pressure in the chamber during film formation: 1 × 10 ⁻³ Torr
・ Temperature of substrate holder: 200 ℃
Processing time: 15 minutes The second bonding film formed as described above contains indium atoms as metal atoms, and a part of the organic substance contained in In (DPM) ₂ remains as a leaving group. It is what.
Thereby, the base material with the 2nd bonding film in which the 2nd bonding film was formed on the glass substrate was obtained.

Next, the obtained first bonding film and second bonding film were each irradiated with ultraviolet rays under the following conditions.
<Ultraviolet irradiation conditions>
-Atmospheric gas composition: Nitrogen gas-Atmospheric gas temperature: 25 ° C
・ Atmospheric gas pressure: Atmospheric pressure (100 kPa)
UV wavelength: 172 nm
・ UV irradiation time: 15 minutes

Next, one minute after irradiating the ultraviolet rays, the single crystal silicon substrate and the glass substrate are overlapped with each other at 10 MPa so that the surfaces irradiated with the ultraviolet rays of the bonding films are in contact with each other. Pressurized and maintained for 15 minutes to obtain a joined body.
Next, the obtained joined body was heated at 160 ° C. (temperature equal to or higher than the melting point of indium) to obtain a joined body joined more firmly than in the temporarily joined state.

(Example 2)
A joined body was obtained in the same manner as in Example 1 except that the pressure when pressing the substrates was changed from 10 MPa to 4 MPa.
(Examples 3 to 13)
A joined body was obtained in the same manner as in Example 1 except that the constituent material of the first substrate and the constituent material of the second substrate were changed to the materials shown in Table 1, respectively.

(Example 14)
First, in the same manner as in Example 1, a single crystal silicon substrate and a glass substrate (first substrate and second substrate) were prepared, and surface treatment with oxygen plasma was performed on each.
Next, a first bonding film was formed on the surface of the silicon substrate subjected to the surface treatment in the same manner as in Example 1. This obtained the 1st base material with a joining film.
Further, a second bonding film was formed on the surface of the glass substrate that had been subjected to the surface treatment in the same manner as in Example 1. This obtained the 2nd base material with a bonding film.

Next, the substrate with the first bonding film and the base with the second bonding film are so arranged that the bonding film of the substrate with the first bonding film and the bonding film of the substrate with the second bonding film come into contact with each other. Overlaid with material.
Then, the superposed substrates were irradiated with ultraviolet rays under the following conditions.
<Ultraviolet irradiation conditions>
-Atmospheric gas composition: Nitrogen gas-Atmospheric gas temperature: 25 ° C
・ Atmospheric gas pressure: Atmospheric pressure (100 kPa)
UV wavelength: 172 nm
-UV irradiation time: 15 minutes After UV irradiation, each substrate was pressurized at 6 MPa while the single crystal silicon substrate and the glass substrate were superposed, and maintained for 15 minutes to obtain a joined body.

(Reference Example 1)
The first bonding film was formed on the glass substrate (second substrate) by using the MOCVD method with Cu (DPM) ₂ as the raw material, that is, the first substrate and the second substrate. A bonded body was obtained in the same manner as in Example 1 except that a first bonding film using Cu (DPM) ₂ as a raw material was formed on both sides.
(Reference Examples 2 and 3)
A joined body was obtained in the same manner as in Reference Example 1 except that the constituent material of the first substrate and the constituent material of the second substrate were the materials shown in Table 1, respectively.

(Comparative Examples 1-3)
The constituent material of the first substrate and the constituent material of the second substrate are the materials shown in Table 2, respectively, and bonding is performed in the same manner as in Example 1 except that the base materials are bonded with an epoxy adhesive. Got the body.
(Comparative Examples 4-6)
The constituent material of the first substrate and the constituent material of the second substrate were the materials shown in Table 2, respectively, and the bonded body was formed in the same manner as in Example 1 except that the base materials were bonded with Ag paste. Obtained.

2. 2. Evaluation of Bonded Body 2.1 Evaluation of Bonding Strength (Split Strength) The bonding strength was measured for each of the bonded bodies obtained in each Example, each Reference Example, and each Comparative Example.
The measurement of the bonding strength was performed by measuring the strength immediately before each substrate was peeled off. Then, the bonding strength was evaluated according to the following criteria.

<Evaluation criteria for bonding strength>
◎: 10 MPa (100 kgf / cm ² ) or more ○: 5 MPa (50 kgf / cm ² ) or more, less than 10 MPa (100 kgf / cm ² ) Δ: 1 MPa (10 kgf / cm ² ) or more, less than 5 MPa (50 kgf / cm ² ) ×: Less than 1 MPa (10 kgf / cm ² )

2.2 Evaluation of dimensional accuracy The dimensional accuracy in the thickness direction was measured for each joined body obtained in each example, each reference example, and each comparative example.
The measurement of the dimensional accuracy was performed by measuring the thickness of each corner of the square joined body and calculating the difference between the maximum value and the minimum value of the thicknesses at the four locations. This difference was evaluated according to the following criteria.
<Evaluation criteria for dimensional accuracy>
○: Less than 10 μm ×: 10 μm or more

2.3 Evaluation of chemical resistance The joined bodies obtained in each Example, each Reference Example and each Comparative Example were immersed in an ink for an ink jet printer maintained at 80 ° C. (manufactured by Epson, “HQ4”) for 3 weeks. . Thereafter, each base material was peeled off, and it was confirmed whether or not ink entered the bonding interface. The results were evaluated according to the following criteria.

<Evaluation criteria for chemical resistance>
◎: Not penetrated at all ○: Slightly penetrated into the corner △: Infiltrated along the edge ×: Intruded inside

2.4 Evaluation of Resistivity For the laminates obtained in Examples 12 and 13 and Comparative Examples 5 and 6, the resistivity of the joint portion was measured. The measured resistivity was evaluated according to the following criteria.
<Evaluation criteria for resistivity>
○: Less than 1 × 10 ⁻³ Ω · cm ×: 1 × 10 ⁻³ Ω · cm or more Table 1 shows the evaluation results of 2.1 to 2.4.

As is apparent from Table 1, the joined bodies obtained in each Example exhibited excellent characteristics in all items of joining strength, dimensional accuracy, chemical resistance and resistivity.
On the other hand, the joined bodies (joined bodies) obtained in Comparative Examples 1 to 6 and Reference Examples 1 to 3 were inferior in bonding strength to each example.
Moreover, the chemical resistance was not sufficient for the joined bodies obtained in Comparative Examples 1 to 6. Also, it was recognized that the dimensional accuracy was particularly low. Furthermore, the joined bodies obtained in Comparative Examples 5 and 6 had high resistivity.

It is a figure (longitudinal sectional view) for demonstrating 1st Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 1st Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 1st Embodiment of the joining method of this invention. In the joining method of this invention, it is the elements on larger scale which show the state before energy provision of a joining film | membrane. In the joining method of this invention, it is the elements on larger scale which show the state after the energy provision of a joining film | membrane. The longitudinal cross-sectional view which shows typically the film-forming apparatus used for the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 2nd Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 2nd Embodiment of the joining method of this invention. It is a figure (longitudinal section) for explaining a 3rd embodiment of the joining method of the present invention. It is a figure (longitudinal section) for explaining a 3rd embodiment of the joining method of the present invention. It is a disassembled perspective view which shows the inkjet recording head (droplet discharge head) obtained by applying the conjugate | zygote of this invention. It is sectional drawing which shows the structure of the principal part of the inkjet recording head shown in FIG. It is the schematic which shows embodiment of an inkjet printer provided with the inkjet recording head shown in FIG. It is a perspective view which shows the wiring board obtained by applying the conjugate | zygote of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Base material with 1st bonding film 12 ... 2nd base material with bonding film 21 ... 1st board | substrate, 22 ... 2nd board | substrate 251, 252 ... Top surface 31 ... 1st joining Film 32... Second bonding film 303... Leaving group 304... Active hand 3 c... Gaps 351 and 352... Surface 350 ... Predetermined regions 5 and 5 b. Mask 61 ... Window part 200 ... Film forming device 211 ... Chamber 212 ... Substrate holder 221 ... Shutter 230 ... Exhaust means 231 ... Exhaust line 232 ... Pump 233 ... Valve 260 ... Organic metal material supply Means 261 ... Gas supply line 262 ... Reservoir 263 ... Valve 264 ... Pump 265 ... Gas cylinder 270 ... Gas supply means 271 ... Gas supply line 273 ... Lub 274 ... Pump 275 ... Gas cylinder 10 ... Inkjet recording head 110 ... Nozzle plate 111 ... Nozzle hole 114 ... Coating 120 ... Ink chamber substrate 121 ... Ink chamber 122 ... Side wall 123 ... Reservoir chamber 124 …… Supply port 13 …… Vibration plate 131 …… Communication hole 14 …… Piezoelectric element 141 …… Upper electrode 142 …… Lower electrode 143 …… Piezoelectric layer 16 …… Substrate 161 …… Recessed portion 162 …… Step 17 ... Head body 9 ... Inkjet printer 92 ... Apparatus body 921 ... Tray 922 ... Paper discharge port 93 ... Head unit 931 ... Ink cartridge 932 ... Carriage 94 ... Printing device 941 ... Carriage motor 942 ... Reciprocating mechanism 943 …… Carriage guide shaft 944 …… Tie Mining belt 95 …… Feeding device 951 …… Feeding motor 952 …… Feeding roller 952a …… Following roller 952b …… Drive roller 96 …… Control unit 97 …… Operation panel P …… Recording paper 410 …… Wiring board 412: Electrode 413: Insulating substrate 414: Lead 415 ... Electrode M1: First metal atom M2: Second metal atom

Claims (32)

A first bonding film including a first metal atom and a leaving group composed of an organic component is formed on the first substrate to obtain a first substrate with the bonding film, and second A second bonding film including a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component is formed on the base material of the second bonding film. Obtaining an attached substrate;
Energy is imparted to the first bonding film and the second bonding film, and the leaving group existing near the surfaces of the first bonding film and the second bonding film is removed from these bonding films. Causing the first bonding film and the second bonding film to exhibit adhesion by desorption, and
The first bonding film and the second bonding film-attached substrate are bonded together so that the first bonding film and the second bonding film are in close contact with each other, and the first bonding is performed. Obtaining a bonded body in which a film and the second bonding film are bonded;
And heating the first bonding film and the second bonding film until the second metal atoms are melted, thereby improving the bonding strength of the bonded body. . A first bonding film including a first metal atom and a leaving group composed of an organic component is formed on the first substrate to obtain a first substrate with the bonding film, and second A second bonding film including a second metal atom having a melting point lower than that of the first metal atom and a leaving group composed of an organic component is formed on the base material of the second bonding film. Obtaining an attached substrate;
A step of obtaining a laminate by superimposing the first substrate with a bonding film and the second substrate with a bonding film so that the first bonding film and the second bonding film are in close contact with each other. When,
Energy is imparted to the first bonding film and the second bonding film, and the leaving group present in the vicinity of the surfaces of the first bonding film and the second bonding film is converted into these bonding films. By desorbing from the first bonding film, the first bonding film and the second bonding film exhibit adhesiveness, and a bonded body in which the first bonding film and the second bonding film are bonded is obtained. Process,
And heating the first bonding film and the second bonding film until the second metal atoms are melted, thereby improving the bonding strength of the bonded body. .   The joining method according to claim 1, wherein a melting point of the second metal atom is lower than 250 ° C. 3.   The bonding method according to claim 3, wherein the second metal atom is at least one of indium, selenium, and tin.   Each of the first bonding film and the second bonding film is formed by using a metal organic chemical vapor deposition method using an organic metal material including the first metal atom and the second metal atom as a raw material. The joining method according to claim 1, wherein a film is formed.   The bonding method according to claim 5, wherein each of the first bonding film and the second bonding film is formed in a low reducing atmosphere.   The bonding method according to claim 5, wherein the leaving group is a residue of a part of an organic substance contained in the organometallic material.   The said leaving group is a carbon atom as an essential component, and is comprised by the atomic group containing at least 1 sort (s) of a hydrogen atom, a nitrogen atom, a phosphorus atom, a sulfur atom, and a halogen atom. The joining method described.   The bonding method according to claim 8, wherein the leaving group includes an alkyl group.   The joining method according to claim 5, wherein the organometallic material is a β-diketone complex.   The bonding method according to claim 1, wherein each of the first bonding film and the second bonding film has conductivity.   The bonding method according to claim 1, wherein a difference in standard electrode potential between the first metal atom and the second metal atom is 3.0 mV or more.   The bonding method according to claim 1, wherein the first metal atom is at least one of copper, aluminum, and silver.   The abundance ratios of the first metal atom and the second metal atom to the carbon atom in the first bonding film and the second bonding film are respectively 3: 7 to 7: 3. 14. The joining method according to any one of 13 to 13.   15. The first bonding film and the second bonding film, respectively, wherein an active hand is generated after the leaving group existing at least near the surface of the first bonding film and the second bonding film are released from each bonding film. The joining method according to any one of the above.   The joining method according to claim 15, wherein the active hand is a dangling hand or a hydroxyl group.   The bonding method according to claim 1, wherein average thicknesses of the first bonding film and the second bonding film are each 1 to 1000 nm.   The bonding method according to claim 1, wherein each of the first bonding film and the second bonding film is in a solid state having no fluidity.   The joining method according to claim 1, wherein the first base material and the second base material have a plate shape.   At least a portion of the first base material forming the first bonding film and at least a portion of the second base material forming the second bonding film are made of a silicon material, a metal material, or a glass material, respectively. The joining method according to claim 1, wherein the joining method is configured as a main material.   The surface of the first base material on which the first bonding film is formed and the surface of the second base material on which the second bonding film is formed are respectively preliminarily formed on the first bonding film and the surface of the first base material. The bonding method according to any one of claims 1 to 20, wherein a surface treatment for improving adhesion with the second bonding film is performed.   The bonding method according to claim 21, wherein the surface treatment is a plasma treatment.   The intermediate layer is interposed between the first base material and the first bonding film and between the second base material and the second bonding film, respectively. The joining method according to the above.   The bonding method according to claim 23, wherein the intermediate layer is formed of an oxide-based material as a main material.   The application of energy is performed by irradiating the first bonding film and the second bonding film with energy rays, heating the first bonding film and the second bonding film, and the first bonding film. The bonding method according to claim 1, wherein the bonding method is performed by at least one method of applying a compressive force to the bonding film and the second bonding film.   The bonding method according to claim 25, wherein the energy beam is an ultraviolet ray having a wavelength of 126 to 300 nm.   27. The bonding method according to claim 25 or 26, wherein a temperature for heating the first bonding film and the second bonding film is not higher than a melting point of the second metal atom.   The joining method according to any one of claims 25 to 27, wherein the compressive force is 0.2 to 10 MPa.   The bonding method according to claim 1, wherein the energy is applied in an air atmosphere.   Furthermore, the joining method in any one of Claim 1 thru | or 29 which has the process of performing the process which raises the joining strength further with respect to the said conjugate | zygote.   The bonding method according to claim 30, wherein the step of performing the process of increasing the bonding strength is performed by at least one of a method of irradiating the bonded body with energy rays and a method of applying a compressive force to the bonded body.   32. A joined body joined by the joining method according to claim 1.

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