JP2011236349A - Bonding film transfer sheet and bonding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding film transfer sheet that can easily transfer a bonding film to a surface of a member, thereby easily bonding the member on which the bonding film is transferred and another member; and to provide a method of efficiently bonding the two members by using the bonding film transfer sheet.SOLUTION: The bonding film transfer sheet 1a is used for transferring the bonding film 3 to an adherend 5a and has: a base material 2a; and the bonding film 3 provided on one surface of the base material. Detachability is provided to the base material 2a and bonding film 3.The bonding film 3 comprises: an Si skeleton having an atomic structure containing siloxane (Si-O) bond; and a leaving group bonding to the Si skeleton and configured by an organic group. By applying energy to at least part of a region of the bonding film 3, the leaving group is detached from the Si skeleton and adhesiveness is developed on the bonding film 3. The bonding film 3 is bonded to the adherend 5a by using the adhesiveness and is peeled at an interface with the base material 2a.

Description

  The present invention relates to a bonding film transfer sheet and a bonding method.

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.
For example, in a droplet discharge head (inkjet recording head) provided in a conventional inkjet printer, members made of different materials such as a resin material, a metal material, and a silicon-based material are bonded together using an adhesive (for example, , See Patent Document 1).
Thus, when bonding a member using an adhesive agent, a liquid or paste-like adhesive agent is apply | coated to an adhesive surface, and members are bonded together through the apply | coated adhesive agent. Thereafter, the bonding is completed by curing the adhesive by the action of heat or light.

  However, when applying an adhesive to the bonding surface of the member, it is necessary to use a complicated method such as a printing method. For example, when an adhesive is selectively applied to a partial region of the adhesive surface, it is extremely difficult to strictly control the position accuracy and thickness of the application. For this reason, it is difficult to bond the members of the droplet discharge head with high dimensional accuracy by the bonding method using the adhesive. As a result, it has been difficult to sufficiently improve the printing accuracy of the printer.

Also, since the curing time of the adhesive becomes very long, it takes a long time to bond, and the positions of the members are shifted during curing, or between members having a difference in thermal expansion coefficient due to heating during curing Thermal stress remains at the adhesive interface, which may cause deformation and damage of the droplet discharge head.
Further, depending on the constituent material of the member, it is necessary to use a primer in order to increase the bonding strength, and the cost and labor for that purpose complicate the bonding process.

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.
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, there is a problem that the members are limited because there are restrictions on the constituent materials that can be joined. In general, materials that can be joined are limited to silicon-based materials and some metal materials, and only the same kind of materials can be joined.
Further, the atmosphere for performing solid bonding is limited to a reduced-pressure atmosphere, and there is a limitation in the bonding process, such as requiring high-temperature (700 to 800 ° C.) heat treatment.

Furthermore, in solid joining, since the whole surface which mutually contacts is joined among each joining surface of two members, it is difficult to selectively join a part. For this reason, even if members made of different materials can be joined, a large stress is generated at the joining interface due to the difference in thermal expansion coefficient, which may cause problems such as warpage and peeling of the joined body. .
In response to such a problem, a method for selectively joining two members firmly with high dimensional accuracy selectively in a partial region of the joining surface is required.

Therefore, Patent Document 2 proposes a method of bonding members using a bonding film formed by plasma polymerization.
Since such a bonding film is formed by a vapor deposition method, it is easier to strictly control the positional accuracy and thickness of the bonding film than in the past. However, when patterning a bonding film formed by plasma polymerization, it is necessary to remove unnecessary portions by using a photolithography technique and an etching technique, and there is a concern that the manufacturing process is complicated and the cost is increased.
Further, in Patent Document 2, since it is necessary to form a bonding film on the surface of a member used for bonding, the film forming apparatus and the member are inseparable, and a member must be prepared where the film forming apparatus is located. Don't be. However, since the film forming apparatus is large in size, heavy in weight, and extremely low in portability, there is a concern that the manufacturing process of the product may involve geographical restrictions on the flow lines of the members.

JP 2002-254660 A JP 2008-307873 A

  An object of the present invention is to allow a bonding film to be easily transferred onto the surface of a member, and thus a bonding film transfer sheet that enables easy bonding between a member to which the bonding film has been transferred and another member, and the like. An object of the present invention is to provide a bonding method for efficiently bonding two members together using a bonding film transfer sheet.

The above object is achieved by the present invention described below.
The bonding film transfer sheet of the present invention is a bonding film transfer sheet used for transferring a bonding film to an adherend,
A substrate;
A bonding film provided on one surface of the substrate;
The base material and the bonding film have peelability,
The bonding film includes a Si skeleton having an atomic structure including a siloxane (Si—O) bond, and a leaving group bonded to the Si skeleton and including an organic group.
The bonding film imparts energy to at least a part of the bonding film, and bonds to the adherend using the adhesiveness developed in the bonding film when the leaving group is released from the Si skeleton. And can be peeled off at the interface with the substrate.
As a result, a bonding film transfer sheet that enables easy bonding between the member (first adherend) to which the bonding film has been transferred and the other member (second adherend) can be obtained.

In the bonding film transfer sheet of the present invention, among the atoms obtained by removing H atoms from all atoms constituting the bonding film, the total of the Si atom content and the O atom content is 10 atomic% or more and 90 atomic% or less. It is preferable that
Thereby, in the bonding film, Si atoms and O atoms form a strong network, and the bonding film itself becomes strong. Further, such a bonding film exhibits a particularly high bonding strength with respect to the first adherend and the second adherend.

In the bonding film transfer sheet of the present invention, the abundance ratio of Si atoms and O atoms in the bonding film is preferably 3: 7 or more and 7: 3 or less.
As a result, the stability of the bonding film is increased, and the first adherend and the second adherend can be bonded more firmly.
In the bonding film transfer sheet of the present invention, the crystallinity of the Si skeleton is preferably 45% or less.
As a result, the Si skeleton particularly includes a random atomic structure. And the joining film excellent in dimensional accuracy and adhesiveness is obtained.

In the bonding film transfer sheet of the present invention, the bonding film preferably contains Si—H bonds.
Si-H bonds are thought to inhibit the regular formation of siloxane bonds. For this reason, the siloxane bond is formed so as to avoid the Si—H bond, and the regularity of the Si skeleton is lowered. In this manner, the Si skeleton having a low degree of crystallinity can be efficiently formed by including Si—H bonds in the bonding film.

In the bonding film transfer sheet of the present invention, in the infrared absorption spectrum of the bonding film containing the Si—H bond, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the Si—H bond is It is preferable that it is 0.001 or more and 0.2 or less.
As a result, the atomic structure in the bonding film becomes relatively random. For this reason, the bonding film is particularly excellent in bonding strength, chemical resistance and dimensional accuracy.

In the bonding film transfer sheet of the present invention, the leaving group is preferably an alkyl group.
Thereby, a bonding film excellent in weather resistance and chemical resistance can be obtained.
In the bonding film transfer sheet of the present invention, in the infrared absorption spectrum of the bonding film containing a methyl group as the leaving group, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the methyl group is It is preferably 0.05 or more and 0.45 or less.
As a result, the content ratio of the methyl group is optimized, and a necessary and sufficient number of active hands are generated in the bonding film while preventing the methyl group from unnecessarily inhibiting the formation of the siloxane bond. Adhesiveness is sufficient. Further, the bonding film exhibits sufficient weather resistance and chemical resistance due to the methyl group.

In the bonding film transfer sheet of the present invention, the bonding film is preferably made of polyorganosiloxane.
As a result, a bonding film superior in adhesiveness can be obtained. In addition, the bonding film has excellent weather resistance and chemical resistance, and is effectively used for bonding adherends that are exposed to chemicals or the like for a long time.

In the bonding film transfer sheet of the present invention, the polyorganosiloxane preferably contains a polymer of octamethyltrisiloxane as a component.
Thereby, a bonding film having particularly excellent adhesiveness can be obtained.
In the bonding film transfer sheet of the present invention, the bonding film is preferably formed by plasma polymerization.
As a result, a dense and homogeneous bonding film can be efficiently produced, and a bonding film that can be particularly strongly bonded to the adherend is obtained.

In the bonding film transfer sheet of the present invention, in the plasma polymerization, the high frequency output density when generating plasma is preferably 0.01 W / cm ² or more and 100 W / cm ² or less.
This makes it possible to reliably form a Si skeleton having a random atomic structure while preventing the plasma gas from being added to the source gas more than necessary due to the high frequency power density.

In the bonding film transfer sheet of the present invention, the average thickness of the bonding film is preferably 1 nm or more and 1000 nm or less.
Thereby, these can be joined more firmly, preventing the dimensional accuracy of the joined body which joined the 1st to-be-adhered body and the 2nd to-be-adhered body falling remarkably.
In the bonding film transfer sheet of the present invention, it is preferable that the bonding film is a solid having no fluidity.
Thereby, the dimensional accuracy of the joined body obtained by using the joining film transfer sheet is remarkably higher than the conventional one. In addition, stronger bonding can be achieved in a shorter time than in the past.

In the bonding film transfer sheet of the present invention, it is preferable that the base material has flexibility.
Accordingly, even if the surface of the first adherend is uneven, the bonding film transfer sheet can be deformed along the uneven shape, so that the bonding film transfer sheet is formed on the first adherend. When laminating, adhesion at the lamination interface can be improved.

In the bonding film transfer sheet of the present invention, the base material is preferably made of a resin material.
Thereby, since a base material becomes a thing excellent in flexibility especially, the joining film | membrane transfer sheet with higher adhesiveness with respect to a 1st to-be-adhered body is obtained. In particular, even when curved with a small radius of curvature, the possibility of breakage is reduced, so that the peeling process can be performed easily and reliably.

In the bonding film transfer sheet of the present invention, the resin material is preferably any one of a fluororesin, a polyolefin, a polyester, and a polyimide.
As a result, the substrate is particularly excellent in flexibility and also has excellent releasability from the bonding film. For this reason, even when it is curved with a small radius of curvature, a bonding film transfer sheet can be obtained that can easily and reliably perform the peeling process while preventing the base material from being broken.

In the bonding film transfer sheet of the present invention, it is preferable that the substrate has a surface energy smaller than that of the adherend.
As a result, the first adherend has a relatively high adhesion to the bonding film and is firmly bonded to the bonding film, while the substrate has a relatively low adhesion to the bonding film. Therefore, the bonding film is surely transferred to the first adherend.

In the bonding film transfer sheet of the present invention, the surface energy of the base material is preferably 5 mN / m or more and 200 mN / m or less.
Accordingly, unintended peeling at the interface between the base material and the bonding film can be prevented and an appropriate peeling force can be applied to cause peeling at the interface between the base material and the bonding film.
In the bonding film transfer sheet of the present invention, it is preferable that the base material has a convex portion on a part of the surface, and the bonding film is formed so as to cover the surface.
Accordingly, the bonding film can be transferred to the first adherend having flexibility.

In the bonding film transfer sheet of the present invention, it is preferable that the bonding film transfer sheet further has a cover sheet that covers the surface of the bonding film.
As a result, the surface of the bonding film can be protected, and adhesion or damage of foreign matters can be prevented. As a result, a bonding film transfer sheet having excellent durability and suitable for long-term storage and distribution can be obtained.
In the bonding film transfer sheet of the present invention, the cover sheet preferably has a surface energy smaller than that of the substrate.
As a result, the cover sheet exhibits a relatively low adhesion to the bonding film, while the base material exhibits a relatively high adhesion to the bonding film. A cover sheet that can be reliably peeled is obtained by preventing the gaps from being joined.

The bonding method of the present invention is a bonding method of bonding the adherend and another adherend using the bonding film transfer sheet of the present invention,
Energy is applied to the surface of the bonding film of the bonding film transfer sheet, the leaving group is desorbed from the Si skeleton, and adhesiveness is exhibited, so that the surface of the bonding film and the adherend are in close contact with each other. A first step of stacking the bonding film transfer sheet and the adherend to obtain a first temporary bonded body,
A second step of peeling the base material from the first temporary bonded body, transferring the bonding film to the adherend, and obtaining a second temporary bonded body;
Energy is imparted to the release surface of the bonding film of the second temporary bonded body, the leaving group is released from the Si skeleton, and the adhesiveness is exhibited, and the release surface of the bonding film and the other covered surface are exposed. The second temporary joined body and the other adherend are stacked so as to be in close contact with the adherend, and a third step of obtaining a joined body is provided.
Thereby, two members can be efficiently joined using a joining film transfer sheet.

In the bonding method of the present invention, the application of energy in the first step may be performed by a method of applying a pressing force to the first temporary bonded body so that the substrate and the adherend are brought closer. preferable.
Thereby, the region to which the bonding film is transferred can be easily controlled only by appropriately setting the region to which the pressing force is applied.

In the joining method of the present invention, the pressing force is preferably 0.2 MPa or more and 10 MPa or less.
Thereby, the adhesiveness can be expressed as necessary and sufficiently in the bonding film. Moreover, although this pressure may exceed the said upper limit, there exists a possibility that damage etc. may arise depending on each structural material of a base material or a 1st to-be-adhered body.

In the bonding method of the present invention, the adherend has a convex portion on a part of its surface, and the bonding film transfer is performed so that the convex portion and the bonding film are in close contact with each other in the first step. By laminating the sheet and the adherend, in the second step, the bonding film in a portion in contact with the convex portion is selectively transferred, and in the third step, the adherend and It is preferable to partially join the other adherend.
As a result, the bonding film can be efficiently and simply patterned simply by selecting the shape of the convex portion as appropriate, and the first adherend and the second adherend are bonded via the bonding film obtained thereby. Partially efficient joining is possible.

It is a figure (longitudinal sectional view) for explaining a first embodiment of a bonding film transfer sheet and a bonding method of the present invention. It is a figure (longitudinal sectional view) for explaining a first embodiment of a bonding film transfer sheet and a bonding method of the present invention. It is the elements on larger scale which show the state before energy provision of the joining film with which the joining film transfer sheet of this invention is provided. It is the elements on larger scale which show the state after the energy provision of the joining film with which the joining film transfer sheet of this invention is provided. It is a longitudinal cross-sectional view which shows typically the plasma polymerization apparatus used for the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating the method of producing a joining film | membrane on a base material. It is a perspective view which shows typically the structure of the joining apparatus used in 1st Embodiment of the joining method of this invention. It is a perspective view which shows typically the structure of the joining apparatus used in 1st Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for explaining a second embodiment of the bonding film transfer sheet and the bonding method of the present invention. It is a figure (longitudinal sectional view) for explaining a second embodiment of the bonding film transfer sheet and the bonding method of the present invention. It is a perspective view which shows typically the structure of the joining apparatus used in 2nd Embodiment of the joining method of this invention.

Hereinafter, a bonding film transfer sheet and a bonding method of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<First Embodiment>
First, a first embodiment of the bonding film transfer sheet and the bonding method of the present invention will be described.
1 and 2 are diagrams (longitudinal sectional views) for explaining the first embodiment of the bonding film transfer sheet and bonding method of the present invention, and FIG. 3 is a drawing of the bonding film provided in the bonding film transfer sheet of the present invention. FIG. 4 is a partially enlarged view showing a state after energy application of the bonding film provided in the bonding film transfer sheet of the present invention. In the following description, the upper side in FIGS. 1 and 2 is referred to as “upper” and the lower side is referred to as “lower”.

A bonding film transfer sheet 1a shown in FIG. 1 includes a base material 2a and a bonding film 3 formed on the base material 2a. The bonding film 3 is bonded to an arbitrary first adherend 5a. It is used to transfer.
The bonding film 3 is formed, for example, by plasma polymerization, and includes a Si skeleton having an atomic structure including a siloxane (Si—O) bond and a leaving group bonded to the Si skeleton. Further, the base material 2 a has peelability from the bonding film 3.

  In such a bonding film 3, energy is applied to at least a part of the bonding film 3, whereby a leaving group existing in the bonding film 3 is released from the Si skeleton, and the bonding film 3 is bonded to the region to which energy is applied. Is expressed. Further, the bonding film 3 is bonded to the first adherend 5a using this adhesive property, and is transferred to the first adherend 5a by peeling at the interface with the substrate 2a. .

Incidentally, the bonding film transfer sheet 1a is used in the bonding method of the present invention as follows.
In the bonding method according to the present embodiment, energy is applied to the upper surface (surface) of the bonding film 3 of the bonding film transfer sheet 1a, and the bonding film 3 and the first adherend 5a are in close contact with each other. By laminating the transfer sheet 1a and the first adherend 5a to obtain the first temporary joined body 7, and by peeling the substrate 2a from the first temporary joined body 7, Energy is applied to the second step of transferring the bonding film 3 to the adherend 5a to obtain the second temporary bonded body 8, and the upper surface (peeling surface) of the bonding film 3 of the second temporary bonded body 8. At the same time, a third step of obtaining the joined body 10 by laminating the second temporary joined body 8 and the second adherend 6 so that the bonding film 3 and the second adherend 6 are in close contact with each other. Have

In the second step, the bonding film 3 is transferred to the first adherend 5a using the adhesiveness developed in the bonding film 3. This transfer is performed by peeling the interface between the bonding film 3 and the substrate 2a after bonding the bonding film 3 and the first adherend 5a. As a result, a part of the bonding film 3 (bonding film 33) moves to the first adherend 5a. The first adherend 5a to which the bonding film 33 has been transferred develops adhesiveness by applying energy again to the release surface of the bonding film 33 in the third step, so that the second adherend (others) To the adherend) 6). Thereby, the joined body 10 obtained by joining the first adherend 5a and the second adherend 6 through the joining film 33 is obtained.
The joined body 10 obtained in this way is obtained by firmly joining the first adherend 5a and the second adherend 6 with high dimensional accuracy even at low temperatures.

(Bonding film transfer sheet)
First, the bonding film transfer sheet of the present invention will be described.
The bonding film transfer sheet 1a shown in FIG. 1 has the base material 2a and the bonding film 3 as described above. Hereinafter, the configuration of each part will be described in detail.
The base material 2 a supports the bonding film 3 and has peelability from the bonding film 3. Moreover, the base material 2a shown in FIG. 1 is a board | substrate form (sheet form) whose both surfaces are flat surfaces, and the thickness is uniform as a whole.

  Examples of the constituent material of the substrate 2a include polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), cyclic 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 Copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyethylene terephthalate (PE ), Polyester such as 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 fluororesins, styrene, polyolefin, polychlorination Vinyl, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluoro rubber, chlorinated polyester Various thermoplastic elastomers such as len, epoxy resins, phenol resins, urea resins, melamine resins, aramid resins, unsaturated polyesters, silicone resins, polyurethanes, etc., or copolymers, blends, polymer alloys mainly containing these And fluorine-based inorganic materials such as potassium fluoride titanate, potassium silicofluoride, potassium fluorozirconate, and silicic hydrofluoric acid.

  Of these, the substrate 2a is preferably flexible. Thereby, when the bonding film transfer sheet 1a is laminated with the first adherend 5a, the adhesion at the lamination interface can be enhanced. This is because the base material 2a has flexibility, so that even if the surface of the first adherend 5a is uneven, the bonding film transfer sheet 1a can be deformed along the uneven shape. This is because the adhesion between the two is improved. Therefore, since the base material 2a has flexibility, in the first temporary joined body 7, the uneven lamination of the joining film transfer sheet 1a and the first adherend 5a is suppressed, and the joining film 3 is reliably secured. Can be transferred.

Moreover, when the base material 2a is peeled from the bonding film transfer sheet 1a laminated on the first adherend 5a, the base material 2a can be easily bent. For this reason, the peeling operation is facilitated, and problems such as the base material 2a damaging the bonding film 3 at the time of peeling are prevented.
Furthermore, since the base material 2a has flexibility, the bonding film transfer sheet 1a itself also has flexibility. Since such a bonding film transfer sheet 1a can be wound up in a roll shape, space saving can be achieved during storage and transportation. Further, the bonding film transfer sheet 1a wound up in a roll shape can be easily supplied in a required length by being sequentially fed out. For this reason, when performing the joining method of this invention with a joining apparatus, the joining film | membrane transfer sheet 1a becomes the thing suitable for mass production which was excellent in affinity to an apparatus.

  The base material 2a is preferably a resin-based material as a main material, and the resin-based material is more preferably any one of a fluorine-based resin, polyolefin, polyester, and polyimide. Such a base material 2a is not only excellent in flexibility, but also has excellent peelability with respect to the bonding film 3, so that the effects described above become more remarkable. In particular, even when the base material 2a is bent with a small radius of curvature, the peeling process described above can be easily and reliably performed because the base material 2a is less likely to break. Specific examples of the fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), perfluoroethylene- Examples include propene copolymer (FEP) and ethylene-chlorotrifluoroethylene copolymer (ECTFE).

Furthermore, since the resin-based material is lightweight, even if a large amount of the bonding film transfer sheet 1a is wound up in a roll shape, the roll is comparatively light and excellent in portability, so that handling is easy. .
The average thickness of the base material 2a is appropriately set according to the constituent material and the desired flexibility, but as an example, it is preferably about 0.01 mm to 10 mm, preferably 0.1 mm to 3 mm. More preferably, it is about the following.

  Moreover, it is preferable that the base material 2a is that whose surface energy (surface free energy) is smaller than the surface energy of the 1st to-be-adhered body 5a. As a result, the first adherend 5a exhibits relatively high adhesion to the bonding film 3 and is firmly bonded to the bonding film 3, while the substrate 2a is relative to the bonding film 3. Shows low adhesion. In other words, the interface between the first adherend 5a and the bonding film 3 is bonded relatively firmly, while the bonding strength at the interface between the substrate 2a and the bonding film 3 is relatively low. Thereby, when laminating the bonding film transfer sheet 1a and the first adherend 5a and peeling the substrate 2a from the obtained first temporary joined body 7, the first adherend 5a and It is possible to surely cause peeling at the interface between the base material 2 a and the bonding film 3 without causing peeling at the interface with the bonding film 3. As a result, the bonding film 3 can be reliably transferred to the first adherend 5a.

  The specific surface energy of the substrate 2a is preferably 5 mN / m or more and 200 mN / m or less, and more preferably 10 mN / m or more and 100 mN / m or less. If the surface energy of the substrate 2a is within the above range, the substrate 2a is peeled off at the interface between the substrate 2a and the bonding film 3 when it is not intended when manufactured and distributed as the bonding film transfer sheet 1a. In addition, when the bonding film 3 is transferred to the first adherend 5a, it is easily and surely peeled off at the interface between the substrate 2a and the bonding film 3 by applying an appropriate peeling force. be able to.

On the other hand, the surface energy of the first adherend 5a may be higher than the surface energy of the substrate 2a, but is preferably 1.1 times or more, more preferably 1.5 times or more, and still more preferably. 2 times or more. If there is a difference of this degree, the variation in surface energy of the base material 2a and the first adherend 5a is sufficiently absorbed, so that the magnitude relationship between the adhesion strengths of both is prevented from being partially reversed. can do.
As a constituent material of the first adherend 5a having such a large surface energy, an inorganic material is preferably used as will be described in detail later.

  Further, the surface energy of the substrate 2a is preferably smaller than the surface energy of the first adherend 5a as described above. However, the surface adherence between the first adherend 5a and the bonding film 3 can be achieved by some surface treatment or the like. When the bonding strength is forcibly increased, it is not necessarily small. 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 surface of the first adherend 5a can be cleaned and activated. As a result, the adhesion strength between the first adherend 5a and the bonding film 3 can be reliably increased.

Further, in the physical surface treatment, by increasing the surface roughness of the surface of the first adherend 5a, an anchor effect is generated at the interface between the first adherend 5a and the bonding film 3, and adhesion strength is increased. Improvements can be made.
The bonding film 3 is provided on the upper surface of the base material 2a as described above. As described above, the bonding film 3 is characterized in that adhesiveness is developed in the region by applying energy to at least a part of the region.

  Such a bonding film 3 is formed by, for example, plasma polymerization. As shown in FIG. 3, as shown in FIG. And a leaving group 303 bonded to the Si skeleton 301. Such a bonding film 3 becomes a strong film that is difficult to be deformed due to the influence of the Si skeleton 301 including the siloxane bond 302 and having a random atomic structure. This is presumably because the crystallinity of the Si skeleton 301 becomes low (becomes amorphous), so that defects such as dislocations and misalignments at the crystal grain boundaries hardly occur. For this reason, the bonding film 3 itself has high bonding strength, chemical resistance, light resistance and dimensional accuracy, and the bonded body 10 finally obtained also has high bonding strength, chemical resistance, light resistance and dimensional accuracy. Things are obtained.

When energy is applied to such a bonding film 3, the leaving group 303 is detached from the Si skeleton 301, and active hands 304 are generated on the surface 35 and inside of the bonding film 3 as shown in FIG. 4. As a result, adhesiveness is developed on the surface of the bonding film 3. When such adhesiveness develops, the bonding film 3 can be bonded to the first adherend 5a firmly and efficiently.
Note that the bond energy of the siloxane bond 302 is higher than the bond energy of other bonds related to Si atoms. In other words, the bond energy between the leaving group 303 and the Si skeleton 301 is smaller than the bond energy of the siloxane bond 302 in the Si skeleton 301. For this reason, the bonding film 3 selectively breaks the bond between the leaving group 303 and the Si skeleton 301 and prevents the leaving group 303 from being removed while preventing the Si skeleton 301 from being destroyed by the application of energy. Can be separated.

  Further, such a bonding film 3 is a solid having no fluidity. For this reason, conventionally, the thickness and shape of the adhesive layer (bonding film 3) hardly change compared to a liquid or viscous liquid adhesive. Thereby, the dimensional accuracy of the joined body 10 becomes remarkably higher than the conventional one. Furthermore, since the time required for curing the adhesive is not required, bonding in a short time is possible.

In addition, when the manufactured bonding film transfer sheet 1a is circulated, the bonding film 3 is in a solid state, so that problems such as the bonding film 3 flowing out during distribution or storage are prevented.
Note that, in the bonding film 3, among the atoms obtained by removing H atoms from all atoms constituting the bonding film 3, the total of Si atom content and O atom content is 10 atomic% or more and 90 atomic% or less. Is preferably about 20 atomic% or more and 80 atomic% or less. If Si atoms and O atoms are contained in the above-mentioned range, the bonding film 3 forms a strong network of Si atoms and O atoms, and the bonding film 3 itself becomes strong. In addition, the bonding film 3 exhibits particularly high bonding strength with respect to the first adherend 5a.

The abundance ratio of Si atoms to O atoms in the bonding film 3 is preferably about 3: 7 to 7: 3, more preferably about 4: 6 to 6: 4. By setting the abundance ratio of Si atoms and O atoms to be within the above range, the stability of the bonding film 3 is increased, and the first adherend 5a can be more firmly bonded. Become.
In addition, the crystallinity of the Si skeleton 301 in the bonding film 3 is preferably 45% or less, and more preferably 40% or less. As a result, the Si skeleton 301 includes a sufficiently random atomic structure and exhibits more amorphous characteristics. For this reason, the characteristics of the Si skeleton 301 described above become obvious, and the dimensional accuracy and adhesiveness of the bonding film 3 become more excellent.

Note that the crystallinity of the Si skeleton 301 can be measured by a general crystallinity measurement method, and specifically, a method of measuring based on the intensity of scattered X-rays in a crystal portion (X-ray method). , The method of obtaining from the intensity of the crystallization band of infrared absorption (infrared method), the method of obtaining based on the area under the differential curve of nuclear magnetic resonance absorption (nuclear magnetic resonance absorption method), It can be measured by a chemical method utilizing the difficulty.
Among these, the X-ray method is preferably used from the viewpoint of convenience and the like.

  Further, when the crystallinity of the Si skeleton 301 is measured, the above-described measurement method may be applied to the bonding film 3, but it is preferable to pre-treat the bonding film 3 in advance. Examples of the pretreatment include a treatment for applying energy to the bonding film 3 described later (for example, an ultraviolet irradiation treatment). By applying energy, the leaving group in the bonding film 3 is released, and the crystallinity of the Si skeleton 301 can be measured more accurately.

  The bonding film 3 preferably contains Si—H bonds in the structure. This Si—H bond is generated in the polymer when the silane undergoes a polymerization reaction by a gas phase film forming method such as plasma polymerization. At this time, the Si—H bond is regularly generated as a siloxane bond. It is thought to interfere with what is done. For this reason, the siloxane bond is formed so as to avoid the Si—H bond, and the regularity of the atomic structure of the Si skeleton 301 is lowered. Thus, according to the vapor phase film forming method such as plasma polymerization, the Si skeleton 301 having a low crystallinity can be efficiently formed.

  On the other hand, the greater the Si—H bond content in the bonding film 3, the lower the crystallinity. Specifically, in the infrared absorption spectrum of the bonding film 3, when the intensity of the peak attributed to the siloxane bond is 1, the intensity of the peak attributed to the Si—H bond is 0.001 or more and 0.2 or less. Is preferably about 0.002 to 0.05, more preferably about 0.005 to 0.02. When the ratio of the Si—H bond to the siloxane bond is within the above range, the atomic structure in the bonding film 3 is relatively random. For this reason, when the peak intensity of the Si—H bond is within the above range with respect to the peak intensity of the siloxane bond, the bonding film 3 is particularly excellent in bonding strength, chemical resistance, and dimensional accuracy.

  Further, as described above, the leaving group 303 bonded to the Si skeleton 301 acts to generate an active hand in the bonding film 3 by detaching from the Si skeleton 301. Therefore, although the leaving group 303 is relatively easily and uniformly desorbed by being given energy, it is securely bonded to the Si skeleton 301 so as not to be desorbed when no energy is given. It needs to be a thing.

In the film formation by a gas phase film formation method such as plasma polymerization, the component of the source gas is polymerized to generate a Si skeleton 301 including a siloxane bond and a residue bonded thereto. The residue can be a leaving group 303.
From this point of view, the leaving group 303 includes an H atom, a B atom, a C atom, an N atom, an O atom, a P atom, an S atom, and a halogen atom, or each of these atoms. What consists of at least 1 sort (s) selected from the group which consists of an atomic group arrange | positioned so that it may couple | bond with frame | skeleton 301 is used preferably. 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 bonding film 3 can be made higher.

  Examples of the atomic group (group) arranged so that each atom as described above is bonded to the Si skeleton 301 include, for example, an alkyl group such as a methyl group and an ethyl group, and an alkenyl group such as a vinyl group and an allyl group. Aldehyde group, ketone group, carboxyl group, amino group, amide group, nitro group, halogenated alkyl group, mercapto group, sulfonic acid group, cyano group, isocyanate group and the like.

Among these groups, the leaving group 303 is particularly preferably an organic group, and more preferably an alkyl group. Since the organic group and the alkyl group have high chemical stability, the bonding film 3 including the organic group and the alkyl group has excellent weather resistance and chemical resistance.
Here, when the leaving group 303 is a methyl group (—CH ₃ ) in particular, the preferred content is defined as follows from the peak intensity in the infrared light absorption spectrum.

That is, in the infrared absorption spectrum of the bonding film 3, when the intensity of the peak attributed to the siloxane bond is 1, the intensity of the peak attributed to the methyl group is about 0.05 to 0.45. Preferably, it is about 0.1 or more and 0.4 or less, more preferably about 0.2 or more and 0.3 or less. When the ratio of the peak intensity of the methyl group to the peak intensity of the siloxane bond is within the above range, it is necessary and sufficient in the bonding film 3 while preventing the methyl group from inhibiting the generation of the siloxane bond more than necessary. Since a number of active hands are generated, sufficient adhesiveness is generated in the bonding film 3. Further, the bonding film 3 exhibits sufficient weather resistance and chemical resistance due to the methyl group.
Examples of the constituent material of the bonding film 3 having such characteristics include a polymer containing a siloxane bond such as polyorganosiloxane and an organic group capable of forming a leaving group 303 bonded thereto.

  The bonding film 3 made of polyorganosiloxane itself has excellent mechanical properties. In addition, it exhibits particularly excellent adhesion to many materials. Therefore, the bonding film 3 made of polyorganosiloxane particularly strongly adheres to the substrate 2a and also exhibits a particularly strong adhesion force to the first adherend 5a. As a result, The base material 2a and the 1st to-be-adhered body 5a can be joined firmly.

Polyorganosiloxane usually exhibits water repellency (non-adhesiveness), but when given energy, it can easily desorb organic groups, changes to hydrophilicity, and exhibits adhesiveness. However, there is an advantage that the non-adhesiveness and the adhesiveness can be controlled easily and reliably.
This water repellency (non-adhesiveness) is mainly an effect of organic groups (for example, alkyl groups) contained in the polyorganosiloxane. Therefore, the bonding film 3 made of polyorganosiloxane exhibits an adhesive property on the surface 35 when energy is applied thereto, and at the portion other than the surface 35, the action and effect of the organic group described above is obtained. Has the advantage of being Therefore, such a bonding film 3 has excellent weather resistance and chemical resistance, and is effectively used, for example, in assembling an optical element or a droplet discharge head that is exposed to chemicals for a long time. It will be a thing.

  Further, among polyorganosiloxanes, those mainly composed of a polymer of octamethyltrisiloxane are preferred. The bonding film 3 mainly composed of a polymer of octamethyltrisiloxane is particularly excellent in adhesiveness. Moreover, since the raw material which has octamethyltrisiloxane as a main component is liquid at normal temperature and has an appropriate viscosity, there is also an advantage that it is easy to handle.

The average thickness of the bonding film 3 is preferably about 1 nm to 1000 nm, and more preferably about 2 nm to 800 nm. By setting the average thickness of the bonding film 3 within the above range, the base material 2a and the first adherend 5a are bonded more firmly while preventing the dimensional accuracy of the bonded body 10 from being significantly reduced. be able to.
That is, when the average thickness of the bonding film 3 is less than the lower limit, sufficient bonding strength may not be obtained. On the other hand, when the average thickness of the bonding film 3 exceeds the upper limit, the dimensional accuracy of the bonded body 10 may be reduced.

Furthermore, if the average thickness of the bonding film 3 is within the above range, the shape of the bonding film 3 can be maintained to some extent. For this reason, for example, even when unevenness exists on the bonding surface of the substrate 2a (surface adjacent to the bonding film 3), the bonding film follows the shape of the unevenness depending on the height of the unevenness. 3 can be deposited. As a result, the bonding film 3 can absorb the unevenness and reduce the height of the unevenness generated on the surface. When the bonding film transfer sheet 1a and the first adherend 5a are bonded together, the adhesion between them can be improved.
Note that the degree of the shape followability as described above becomes more significant as the thickness of the bonding film 3 increases. Therefore, the thickness of the bonding film 3 should be as large as possible in order to sufficiently ensure the shape following ability.

  Although the bonding film 3 has been described in detail above, such a bonding film 3 is produced by a vapor deposition method such as plasma polymerization. Among these, according to the plasma polymerization method, a dense and homogeneous bonding film 3 can be efficiently produced. Thereby, the bonding film 3 can be particularly strongly bonded to the first adherend 5a. Furthermore, the bonding film 3 manufactured by the plasma polymerization method is maintained for a relatively long time in a state where energy is applied and activated. For this reason, the manufacturing process of the joined body 10 can be simplified and efficient. In addition to the plasma polymerization method, the bonding film 3 can be produced by various liquid phase film forming methods in addition to various vapor phase film forming methods such as a CVD method (particularly plasma CVD method) and a PVD method.

The bonding film transfer sheet 1a as described above may have a cover sheet provided so as to cover the upper surface of the bonding film 3 as necessary. Such a cover sheet protects the upper surface of the bonding film 3 and prevents adhesion of foreign matters, damage to the bonding film 3 and the like. As a result, the bonding film transfer sheet 1a has excellent durability and is suitable for long-term storage and distribution.
This cover sheet is peeled off before using the bonding film transfer sheet 1a. At this time, since it is necessary to surely peel off at the interface between the bonding film 3 and the cover sheet, the adhesion strength at this interface is preferably smaller than the adhesion strength between the substrate 2 a and the bonding film 3.

  From this point of view, the cover sheet preferably has a surface energy smaller than that of the substrate 2a. As a result, the base material 2a exhibits relatively high adhesion to the bonding film 3 and adheres relatively strongly to the bonding film 3, while the cover sheet exhibits relatively low adhesion to the bonding film 3. Will be shown. As a result, even if energy is unintentionally applied to the bonding film transfer sheet 1a, the cover sheet and the bonding film 3 are prevented from being bonded, and the bonding film 3 is reliably peeled off. A possible cover sheet is obtained.

Specifically, the surface energy of the cover sheet is preferably about 0.3 to 0.95 times the surface energy of the substrate 2a, preferably about 0.4 to 0.9 times. Is more preferable.
Examples of the constituent material of the cover sheet include the same constituent materials as those of the base material 2a described above.
Moreover, since the bonding film transfer sheet 1a may be stored or distributed in a state of being wound in a roll shape, a flexible cover sheet is preferably used as the base sheet 2a.

Hereinafter, a method for producing the bonding film 3 will be described.
First, prior to explaining the method for producing the bonding film 3, a plasma polymerization apparatus used when producing the bonding film 3 by the plasma polymerization method will be described.
FIG. 5 is a longitudinal sectional view schematically showing a plasma polymerization 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 plasma polymerization apparatus 100 shown in FIG. 5 includes a chamber 101, a first electrode 130 that supports the substrate 2a, a second electrode 140, and a power supply circuit 180 that applies a high-frequency voltage between the electrodes 130 and 140. A gas supply unit 190 that supplies gas into the chamber 101 and an exhaust pump 170 that exhausts the gas in the chamber 101 are provided. Among these parts, the first electrode 130 and the second electrode 140 are provided in the chamber 101. Hereinafter, each part will be described in detail.

The chamber 101 is a container that can keep the inside airtight, and is used with the inside being in a reduced pressure (vacuum) state. Therefore, the chamber 101 has pressure resistance that can withstand a pressure difference between the inside and the outside.
The chamber 101 shown in FIG. 5 has a substantially cylindrical chamber body whose axis is arranged along the horizontal direction, a circular side wall that seals the left opening of the chamber body, and a circle that seals the right opening. And side walls.

A supply port 103 is provided above the chamber 101, and an exhaust port 104 is provided below the chamber 101. A gas supply unit 190 is connected to the supply port 103, and an exhaust pump 170 is connected to the exhaust port 104.
In this embodiment, the chamber 101 is made of a highly conductive metal material and is electrically grounded via the ground wire 102.

The first electrode 130 has a plate shape and supports the substrate 2a.
The first electrode 130 is provided on the inner wall surface of the side wall of the chamber 101 along the vertical direction, whereby the first electrode 130 is electrically grounded via the chamber 101. As shown in FIG. 5, the first electrode 130 is provided concentrically with the chamber body.

An electrostatic chuck (suction mechanism) 139 is provided on the surface of the first electrode 130 that supports the substrate 2a.
As shown in FIG. 5, the electrostatic chuck 139 can support the substrate 2a along the vertical direction. Further, even if the base material 2a has a slight warp, the base material 2a can be subjected to a plasma treatment in a state where the warp is corrected by adsorbing the base material 2a to the electrostatic chuck 139.

The second electrode 140 is provided to face the first electrode 130 with the base material 2a interposed therebetween. Note that the second electrode 140 is provided in a state of being separated (insulated) from the inner wall surface of the side wall of the chamber 101.
A high frequency power source 182 is connected to the second electrode 140 via a wiring 184. A matching box (matching unit) 183 is provided in the middle of the wiring 184. The wiring 184, the high-frequency power source 182 and the matching box 183 constitute a power circuit 180.
According to such a power supply circuit 180, since the first electrode 130 is grounded, a high frequency voltage is applied between the first electrode 130 and the second electrode 140. As a result, an electric field whose direction is reversed at a high frequency is induced in the gap between the first electrode 130 and the second electrode 140.

The gas supply unit 190 supplies a predetermined gas into the chamber 101.
A gas supply unit 190 shown in FIG. 5 stores a liquid storage unit 191 that stores a liquid film material (raw material liquid), a vaporizer 192 that vaporizes the liquid film material to change it into a gaseous state, and stores a carrier gas. And a gas cylinder 193. Each of these parts and the supply port 103 of the chamber 101 are connected by a pipe 194, and a mixed gas of a gaseous film material (raw material gas) and a carrier gas is supplied from the supply port 103 into the chamber 101. It is configured to supply.

The liquid film material stored in the liquid storage unit 191 is a raw material that is polymerized by the plasma polymerization apparatus 100 to form a polymer film on the surface of the substrate 2a.
Such a liquid film material is vaporized by the vaporizer 192 and is supplied into the chamber 101 as a gaseous film material (raw material gas). The source gas will be described in detail later.

The carrier gas stored in the gas cylinder 193 is a gas that is discharged due to the action of an electric field and introduced to maintain this discharge. Examples of such a carrier gas include Ar gas and He gas.
A diffusion plate 195 is provided near the supply port 103 in the chamber 101.

The diffusion plate 195 has a function of promoting the diffusion of the mixed gas supplied into the chamber 101. Thereby, the mixed gas can be dispersed in the chamber 101 with a substantially uniform concentration.
The exhaust pump 170 exhausts the inside of the chamber 101, and includes, for example, an oil rotary pump, a turbo molecular pump, or the like. Thus, by exhausting the chamber 101 and reducing the pressure, the gas can be easily converted into plasma. In addition, contamination and oxidation of the base material 2a due to contact with the air atmosphere can be prevented, and reaction products resulting from the plasma treatment can be effectively removed from the chamber 101.
The exhaust port 104 is provided with a pressure control mechanism 171 that adjusts the pressure in the chamber 101. Thereby, the pressure in the chamber 101 is appropriately set according to the operation state of the gas supply unit 190.

Next, a method for producing the bonding film 3 on the substrate 2a using the plasma polymerization apparatus 100 will be described.
FIG. 6 is a diagram (longitudinal sectional view) for explaining a method of producing the bonding film 3 on the substrate 2a. In the following description, the upper side in FIG. 6 is referred to as “upper” and the lower side is referred to as “lower”.
The bonding film 3 can be obtained by supplying a mixed gas of a source gas and a carrier gas in a strong electric field to polymerize molecules in the source gas and deposit a polymer on the substrate 2a. . Details will be described below.

First, the base material 2a is prepared.
Next, after the base material 2a is housed in the chamber 101 of the plasma polymerization apparatus 100 to be in a sealed state, the inside of the chamber 101 is depressurized by the operation of the exhaust pump 170.
Next, the gas supply unit 190 is operated to supply a mixed gas of the source gas and the carrier gas into the chamber 101. The supplied mixed gas is filled into the chamber 101 (see FIG. 6A).

Here, the ratio (mixing ratio) of the source gas in the mixed gas is slightly different depending on the type of the source gas and the carrier gas, the target film forming speed, and the like. For example, the ratio of the source gas in the mixed gas is 20 % Is preferably set to about 70% or less, and more preferably set to about 30% or more and 60% or less. As a result, it is possible to optimize the conditions for formation (film formation) of the polymer film.
Further, the flow rate of the gas to be supplied is appropriately determined depending on the type of gas, the target film formation rate, the film thickness, etc., and is not particularly limited, but usually the flow rates of the source gas and the carrier gas are respectively It is preferably set to about 1 ccm or more and 100 ccm or less, and more preferably set to about 10 ccm or more and 60 ccm or less.

  Next, the power supply circuit 180 is activated, and a high frequency voltage is applied between the pair of electrodes 130 and 140. As a result, gas molecules existing between the pair of electrodes 130 and 140 are ionized to generate plasma. Due to the energy of the plasma, molecules in the raw material gas are polymerized, and as shown in FIG. Thereby, the bonding film 3 made of a plasma polymerization film is formed (see FIG. 6C).

Moreover, the surface of the base material 2a is activated and cleaned by the action of plasma. For this reason, the polymer of the source gas is easily deposited on the surface of the base material 2a, and the bonding film 3 can be stably formed. Thus, according to the plasma polymerization method, the bonding film 3 can be reliably formed on the base material 2a regardless of the constituent material of the base material 2a.
Examples of the source gas include organosiloxanes such as methylsiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, and methylphenylsiloxane.
The plasma polymerized film obtained by using such a raw material gas, that is, the bonding film 3 is composed of a polymer obtained by polymerizing these raw materials, that is, a polyorganosiloxane.

In the plasma polymerization, the frequency of the high frequency applied between the pair of electrodes 130 and 140 is not particularly limited, but is preferably about 1 kHz to 100 MHz, and more preferably about 10 MHz to 60 MHz.
The high frequency output density is not particularly limited, but is preferably about 0.01 W / cm ² or more and 100 W / cm ² or less, more preferably about 0.1 W / cm ² or more and 50 W / cm ² or less. Preferably, it is about 1 W / cm ² or more and 40 W / cm ² or less. By setting the high-frequency power density within the above range, the Si skeleton 301 having a random atomic structure can be reliably secured while preventing the plasma gas from being added to the source gas more than necessary because the high-frequency power density is too high. Can be formed. That is, when the high-frequency output density is lower than the lower limit value, the molecules in the raw material gas cannot cause a polymerization reaction, and the bonding film 3 may not be formed. On the other hand, when the power density of the high frequency exceeds the upper limit, the structure that can be the leaving group 303 is separated from the Si skeleton 301 due to decomposition of the source gas or the like, and the leaving group in the resulting bonding film 3 is separated. There is a possibility that the content of 303 is lowered or the randomness of the Si skeleton 301 is lowered (regularity is increased).

The pressure in the chamber 101 at the time of film formation is preferably about 133.3 × 10 ⁻⁵ Pa to 1333 Pa (1 × 10 ⁻⁵ Torr to 10 Torr), preferably 133.3 × 10 ⁻⁴ Pa. More preferably, it is about 133.3 Pa or less (1 × 10 ⁻⁴ Torr or more and 1 Torr or less).
The raw material gas flow rate is preferably about 0.5 sccm to 200 sccm, more preferably about 1 sccm to 100 sccm. On the other hand, the carrier gas flow rate is preferably about 5 sccm or more and 750 sccm or less, and more preferably about 10 sccm or more and 500 sccm or less.

The treatment time is preferably about 1 to 10 minutes, more preferably about 4 to 7 minutes.
Moreover, it is preferable that the temperature of the base material 2a is 25 degreeC or more, and it is more preferable that it is about 25 degreeC or more and 100 degrees C or less.
The bonding film 3 is obtained as described above.

  The bonding film 3 has a relatively high translucency depending on the thickness. The refractive index of the bonding film 3 can be adjusted by appropriately setting the conditions for forming the bonding film 3 (conditions during plasma polymerization, composition of the raw material gas, and the like). Specifically, the refractive index of the bonding film 3 can be increased by increasing the high frequency power density during plasma polymerization, and conversely, the bonding can be achieved by decreasing the high frequency power density during plasma polymerization. The refractive index of the film 3 can be lowered.

Specifically, according to the plasma polymerization method using a silane-based gas as a raw material, the bonding film 3 having a refractive index range of about 1.35 to 1.6 is obtained. Since the refractive index of such a bonding film 3 is close to that of quartz or quartz glass, for example, it is suitably used when manufacturing an optical component having a structure in which the optical path penetrates the bonding film 3. Further, since the refractive index of the bonding film 3 can be adjusted, the bonding film 3 having a desired refractive index can be manufactured.
In addition, since the bonding film 3 is close to the thermal expansion coefficient of quartz or quartz glass, the difference in the thermal expansion coefficient between the bonding film 3 and the optical component is reduced, and deformation after bonding of the bonded body 10 can be suppressed.

(Joining method)
Next, the joining method of the present invention will be described with reference to FIGS.
In the bonding method according to the present embodiment, as described above, energy is applied to the upper surface (surface) of the bonding film 3 of the bonding film transfer sheet 1a, and the bonding film 3 and the first adherend 5a are in close contact with each other. As described above, the bonding film transfer sheet 1 a and the first adherend 5 a are stacked to obtain the first temporary bonded body 7, and the base material 2 a is peeled from the first temporary bonded body 7. Thus, the second step of transferring a part of the bonding film 3 (bonding film 33) to the first adherend 5a to obtain the second temporary bonded body 8, and the bonding of the second temporary bonded body 8 While applying energy to the upper surface (peeling surface) of the film 33, the second temporary bonded body 8 and the second adherend 6 are bonded so that the bonding film 33 and the second adherend 6 are in close contact with each other. And a third step of obtaining the joined body 10 by laminating. Hereinafter, each process will be described sequentially.

[1] First, a bonding film transfer sheet 1a is prepared (see FIG. 1A).
Next, energy is applied to the upper surface 31 of the bonding film 3 of the bonding film transfer sheet 1a. When energy is applied, adhesiveness develops on the upper surface 31 of the bonding film 3.
As a method of applying energy to the upper surface 31 of the bonding film 3, any method may be used as long as it can activate the upper surface 31. For example, a method of irradiating energy rays, a method of heating, a pressing force ( A method of applying physical energy), a method of exposing to plasma (applying plasma energy), a method of exposing to ozone gas (applying chemical energy), and the like.

  Among these, as a method for applying energy, a method for applying pressing force is preferably used. According to such a method, only the target region of the bonding film 3 can be selectively bonded to the first adherend 5a only by pressing the region to be bonded. As a result, only a part of the bonding film 3 can be transferred to the first adherend 5a. For this reason, it is not necessary to use a special apparatus etc., and a joining process can be performed easily.

For example, when only the region 32 shown in FIG. 1B is transferred in the bonding film 3, the first adherend 5 a having the convex portion 51 in the region corresponding to the region 32 is used.
Next, the bonding film transfer sheet 1a and the first adherend 5a are laminated so that the bonding film 3 and the convex portion 51 are in contact with each other. And the obtained laminated body is pressed in the thickness direction (the direction in which the base material 2a and the first adherend 5a approach) (first step). Thereby, the convex portion 51 selectively presses a part of the bonding film 3, and a pressing force is selectively applied to the region 32 of the bonding film 3. As a result, the first temporary joined body 7 in which the region 32 is partially joined is obtained (see FIG. 1C).
According to such a method, the area to be transferred can be easily changed only by appropriately changing the shape of the convex portion 51 according to the shape (planar shape) of the area 32 to be transferred.

In addition, it is preferable that the lower surface of the convex part 51 in FIG.1 (b) is a flat surface, and it is preferable that the cross-sectional shape of the convex part 51 is a trapezoid or a rectangle. Thereby, the convex part 51 can press a part of the bonding film 3 uniformly and accurately.
Further, the height of the convex portion 51 is not particularly limited, but is preferably about 50 μm or more and 5 mm or less, and more preferably about 100 μm or more and 3 mm or less. As a result, the convex portion 51 reliably prevents defects and the like, and even if the bonding film transfer sheet 1a undulates with the pressing, only the target region is pressed without pressing the non-target region. It can be surely pressed.

Moreover, it is preferable that the 1st to-be-adhered body 5a has rigidity. This prevents the convex portion 51 from being deformed when the laminate is pressed. As a result, it is possible to reliably prevent the shape of the region 32 to be transferred from being deformed and to enable accurate bonding.
Here, it is preferable that the surface of the first adherend 5a that is in contact with the bonding film 3 has a hydroxyl group (OH group) bonded thereto. When the surface of the first adherend 5a is in such a state, the bonding strength between the first adherend 5a and the bonding film 3 is improved, and the bonding film transfer sheet 1a and the first film The adherend 5a can be bonded more firmly. Such an effect is assumed to be due to the following phenomenon.

In this step, when the bonding film 3 and the first adherend 5a are brought into contact (adherence), the hydroxyl groups present on the surface of the first adherend 5a and the activated surface of the bonding film 3 are obtained. Are attracted to each other by hydrogen bonding, and an attractive force is generated between the hydroxyl groups.
Further, the hydroxyl groups attracting each other by this hydrogen bond are dehydrated and condensed depending on the temperature condition or the like. As a result, at the contact interface between the bonding film 3 and the first adherend 5a, the bonds where the detached OH groups are bonded are bonded via oxygen atoms. Thereby, the bonding film 3 and the first adherend 5a are chemically strongly bonded.

  In order to form a state in which the hydroxyl group is bonded to the surface of the region where the bonding film 3 is to be in close contact with the first adherend 5a, for example, oxygen plasma or the like is applied to the first adherend 5a. The method of performing this plasma processing, the method of performing an etching process, the method of irradiating an electron beam, the method of irradiating an ultraviolet light, the method of exposing to ozone, or the method of combining these etc. are mentioned. By using such a method, it is possible to clean the surface of the first adherend 5a and to activate the surface by cutting some of the bonds near the surface. A hydroxyl group (OH group) is naturally bonded to the surface in such a state when surrounding moisture comes into contact therewith. In this way, a state in which hydroxyl groups are bonded can be formed.

Some constituent materials of the first adherend 5a may have a hydroxyl group bonded to the surface without performing the above treatment. Examples of such constituent materials include various metal materials such as stainless steel and aluminum, silicon-based materials such as silicon and quartz glass, and oxide-based ceramic materials (inorganic materials) such as alumina. Note that the first adherend 5a may not be entirely made of the above-described material, and at least the vicinity of the surface only needs to be made of the above-described material.
The surface of the first adherend 5a made of such a material is covered with an oxide film, and a hydroxyl group is bonded to the surface of the oxide film. Therefore, when the first adherend 5a made of such a material is used, the bonding film transfer sheet 1a and the first adherend 5a can be firmly bonded without performing a process for exposing the hydroxyl group. can do.

  Further, the surface and the inside of the first adherend 5a may include active bonds (dangling bonds) that are not terminated. Furthermore, a state where a hydroxyl group and dangling bonds are mixed may be used. When dangling bonds are included in the surface and the inside of the first adherend 5a, the dangling bonds exposed on the surface of the bonding film 3 are derived from covalent bonds constructed in a network shape. Strong bonding is made. As a result, the bonding film transfer sheet 1a and the first adherend 5a can be bonded more firmly.

The first adherend 5a may have a bonding film similar to the bonding film 3 on the surface thereof. As a result, the bonding films are bonded to each other between the bonding film transfer sheet 1a and the first adherend 5a, so that the bonding strength is increased compared to bonding through the single-layer bonding film 3. be able to. Further, strong bonding is possible regardless of the constituent material of the first adherend 5a.
In addition, it is necessary to give energy to the bonding film provided in advance on the surface of the first adherend 5a prior to bonding.

  Further, the activated state of the surface of the activated bonding film 3 to which energy has been imparted relaxes over time. For this reason, it is preferable that the bonding film transfer sheet 1a is laminated on the first adherend 5a as soon as possible after application of energy. Specifically, it is preferable to laminate within 60 minutes after application of energy, and more preferably within 5 minutes. Within such a time, since the surface of the bonding film 3 maintains a sufficiently active state, a sufficient bonding strength can be obtained when bonded.

In other words, the bonding film 3 before activation is chemically stable and excellent in weather resistance. For this reason, the bonding film 3 before activation is suitable for long-term storage. Therefore, if the bonding film transfer sheet 1a is manufactured or purchased in large quantities and stored, and energy is applied immediately before the lamination with the first adherend 5a, the first temporary bonded body 7 is obtained. This is effective from the viewpoint of manufacturing efficiency of the joined body 10.
In the conventional solid bonding such as silicon direct bonding or optical contact, even if the surface is activated, the active state is maintained for only a very short time of several seconds to several tens of seconds in the atmosphere. For this reason, after the surface was activated, there was a problem that it was not possible to ensure sufficient time for performing operations such as bonding the two members to be joined together.

On the other hand, according to the present invention, the active state can be maintained for a relatively long time of several minutes or more even after energy is applied by the action of the plasma polymerized film. For this reason, the time required for the work can be sufficiently secured, and the efficiency of the joining work can be improved.
Further, the pressing force applied to the laminate is preferably about 0.2 MPa or more and 10 MPa or less, and more preferably about 1 MPa or more and 5 MPa or less. Thereby, in the bonding film 3, the adhesiveness can be expressed as necessary and sufficiently. In addition, although this pressure may exceed the said upper limit, there exists a possibility that damage etc. may arise depending on each component material of the base material 2a or the 1st to-be-adhered body 5a.

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 when pressing the laminate, the more sufficient adhesiveness can be expressed even if the pressing time is shortened.
The pressing of the laminate may be performed in any atmosphere, but is preferably performed in an air atmosphere. Thereby, it is not necessary to spend time and cost to control the atmosphere, and the activation process can be performed more easily.

  Besides the method of applying the pressing force, a method of irradiating energy rays or a method of exposing to plasma (plasma treatment) is preferable. According to this method, the upper surface 31 of the bonding film 3 is activated efficiently. Further, according to this method, the molecular structure in the bonding film 3 is not cut more than necessary (for example, until reaching the interface with the base material 2a), so that the characteristics of the bonding film 3 are prevented from being deteriorated. Can do. Further, a plurality of methods may be combined, for example, a method of applying a pressing force after performing a plasma treatment.

Examples of energy rays include light such as ultraviolet light and laser light, electron beams, and particle beams.
In addition, it is preferable to use a method of irradiating ultraviolet rays (for example, a wavelength of about 126 nm or more and about 300 nm or less) for the energy rays. According to such ultraviolet rays, it is possible to process a wide range in a shorter time without unevenness while preventing a significant deterioration in the characteristics of the bonding film 3. For this reason, the upper surface 31 of the bonding film 3 can be activated more efficiently. In addition, ultraviolet rays also have an advantage that they can be generated with simple equipment such as an ultraviolet lamp.

The wavelength of the ultraviolet light is more preferably about 160 nm to 200 nm.
Further, the time for irradiating with ultraviolet rays is not particularly limited as long as the chemical bond in the vicinity of the upper surface 31 of the bonding film 3 can be broken, but it is preferably about 0.5 to 30 minutes. More preferably, it is about 1 minute or more and 10 minutes or less.

Note that, instead of the entire surface of the bonding film 3, an energy beam may be irradiated to a part of the region. In this case, energy beams with high directivities such as laser light and electron beams can be irradiated selectively and easily to a predetermined region by irradiating in a target direction. it can.
Moreover, even if it is an energy ray with low directivity, if it irradiates so that areas other than a predetermined area may be covered, an energy ray can be selectively irradiated with respect to a predetermined area.

On the other hand, atmospheric pressure plasma is preferably used as the plasma exposed to the bonding film 3. According to atmospheric pressure plasma, plasma treatment can be easily performed without using expensive equipment such as decompression means. In addition to the direct plasma method in which plasma is generated in the vicinity of the bonding film 3, a remote plasma method or a downflow plasma method in which the object to be processed and the plasma generation unit are separated is also preferably used for this plasma treatment. According to the direct plasma method, since plasma is generated in the vicinity of the bonding film 3, plasma processing can be performed efficiently and uniformly. In addition, when the object to be processed and the plasma generating part are separated from each other as in the remote plasma method or the down flow plasma method, the object to be processed and the plasma generating part do not interfere with each other. Can be avoided from ion damage.
Further, when the plasma treatment is performed in a reduced pressure atmosphere, there is a possibility that a gas unintentionally confined inside the bonding film 3 or a gas generated over time is forcibly extracted to the outside of the bonding film 3. . When such a phenomenon occurs, the bonding film 3 is damaged, resulting in a decrease in adhesiveness, and an increase in the refractive index is unintentionally changed.

On the other hand, by performing plasma treatment under atmospheric pressure, the bonding film 3 can exhibit adhesiveness without being damaged.
In this way, the surface 31 of the bonding film 3 to which energy has been applied and activated is bonded to an unterminated bond (dangling bond) and a hydroxyl group formed by contacting the bond with water around it (dangling bond). OH group) is exposed. The above-mentioned “activate” means either a state in which the bond near and inside the upper surface 31 is cut and an unterminated bond is generated or a hydroxyl group is bonded to the bond. Or a state in which these states are mixed.
The first temporary joined body 7 can be obtained as described above.

In the first temporary joined body 7 thus obtained, the joining strength between the joining film transfer sheet 1a and the first adherend 5a is preferably 5 MPa (50 kgf / cm ² ) or more, and preferably 10 MPa ( 100 kgf / cm ² ) or more is more preferable. The first temporary bonded body 7 having such bonding strength is an interface between the bonding film 3 and the first adherend 5a when the substrate 2a is peeled from the bonding film transfer sheet 1a in a process described later. Thus, it is possible to reliably prevent peeling.
For laminating the bonding film transfer sheet 1a and the first adherend 5a, various laminating apparatuses and various pressing apparatuses are used.

[2] Next, as shown in FIG. 1 (d), the substrate 2 a is peeled from the first temporary joined body 7. This peeling is performed by peeling the base material 2a from the first temporary joined body 7 so as to widen the interface between the base material 2a and the bonding film 3 (second step). Thereby, a second temporary joined body 8 obtained by transferring a part of the joining film 3 to the first adherend 5a is obtained (see FIG. 2E).
In this peeling, a portion (bonding film 33) of the bonding film 3 facing the convex portion 51 of the first adherend 5a is transferred to the first adherend 5a, and the remaining portion of the bonding film 3 is It is peeled off together with the substrate 2a without being transferred. For this reason, the second temporary bonded body 8 includes the first adherend 5a and the bonding film 33 partially provided on the upper surface of the convex portion 51. By using the bonding film transfer sheet 1a in this manner, the bonding film 3 can be efficiently and simply patterned simply by selecting the shape of the convex portion 51 as appropriate.
Note that the upper surface of the bonding film 33 transferred to the obtained second temporary bonded body 8 is a peeled surface peeled from the substrate 2a.

[3] Next, energy is applied to the upper surface (peeling surface) of the bonding film 33 of the second temporary bonded body 8.
The method for applying energy to the bonding film 33 is the same as the method for applying energy to the bonding film 3 described above. In the present embodiment, a method for applying a pressing force will be described.
First, a second adherend 6 to be joined to the second temporary joined body 8 is prepared. The shape of the second adherend 6 is not particularly limited, and may be either a flat plate shape or a block shape. Here, a flat plate shape will be described as an example.

The constituent material of the second adherend 6 is the same as the constituent material of the substrate 2a.
Next, as shown in FIG. 2 (f), the second temporary bonded body 8 and the second adherend 6 are laminated so that the bonding film 33 and the second adherend 6 are in contact with each other. Then, the obtained laminated body is pressed in the thickness direction (the direction in which the second temporary bonded body 8 and the second adherend 6 approach each other) (third step). Thereby, the convex portion 51 presses the bonding film 33, and a pressing force is applied to the bonding film 33. As a result, the first adherend 5a and the second adherend 6 are bonded via the bonding film 33, and the bonded body 10 is obtained (see FIG. 2G).

The pressing force when pressing the laminated body is the same as the pressing force applied to the laminated body formed by laminating the bonding film transfer sheet 1a and the first adherend 5a.
In addition, as described above, various laminating apparatuses, various pressing apparatuses, and the like can be used for pressing the laminate.
In this way, the bonding film 33 can freely control a region where adhesiveness is developed by selecting a region to which energy is applied. For example, since the bonding film 3 can be patterned according to the shape of the convex portion 51, the bonding film 33 having a finer pattern can be obtained as compared with the conventional patterning method. Specifically, when the line-shaped bonding film 33 adjacent to the gap is formed, the width of the gap can be as small as 1 μm or less.

  Moreover, such an effect cannot be obtained by a conventional joining method such as an adhesive or solid joining, and is extremely useful from the viewpoint of increasing the efficiency of the joining process. That is, since the bonding strength can be easily adjusted by selecting a region to which energy is applied, the local concentration of stress generated in the bonding portion is reduced by optimizing the shape and area of the bonding film 33. be able to. Thereby, the thermal expansion difference produced between the 1st to-be-adhered body 5a and the 2nd to-be-adhered body 6 can be relieve | moderated.

In addition, the bonding film transfer sheet 1a has a sheet-like form that is easy to handle and suitable for distribution and storage, and can simply exhibit strong adhesiveness simply by applying physical or chemical energy. obtain. Therefore, the bonding film transfer sheet 1a has excellent affinity for mass production processes of various products.
Specifically, since the bonding film formed by the plasma polymerization method has conventionally been required to be directly formed on the surface of the member to be bonded, the member is prepared in a place where the film forming apparatus is set. There was a need to do. This is because the film forming apparatus is large and heavy, and cannot be moved easily. However, when there is a geographical restriction that the film forming apparatus and the member are inseparable as described above, there is a problem that the flow line of the member is limited, and the degree of freedom of the manufacturing process of the product is lowered. .

  On the other hand, according to the present invention, the process of forming the bonding film and the process of bonding the members can be performed at different locations. For this reason, if a large amount of the bonding film transfer sheet 1a is manufactured, the bonding film transfer sheet 1a can be transported to a desired location and the members can be bonded at the desired location. As a result, the degree of freedom of the product manufacturing process is dramatically increased, and the mass production efficiency can be improved.

Further, since the bonding film 33 is excellent in bonding strength, chemical resistance, and dimensional accuracy, the obtained bonded body 10 is also excellent in bonding strength, chemical resistance, and dimensional accuracy.
In particular, the bonded body 10 is not bonded based on a physical bond such as an anchor effect like an adhesive used in a conventional bonding method, but is a strong chemical bond that occurs in a short time like a covalent bond. Based on the joining. For this reason, the joined body 10 is extremely difficult to be peeled off, and joining unevenness or the like hardly occurs.

Further, according to the bonding method of the present invention, unlike the conventional solid bonding, a heat treatment at a high temperature (about 700 ° C. or more and about 800 ° C. or less) is not required. Can also be used for bonding. Thereby, the range of selection of the constituent material of a base material can be expanded.
In addition, according to the present invention, in the bonding between the first adherend 5a and the second adherend 6, the peeling surface of the bonding film 33 becomes the bonding interface. For this reason, since this peeling surface is in contact with the base material 2a until immediately before peeling and is protected from the adhesion or damage of foreign matter, it is in a state suitable for good bonding. Furthermore, even when energy is applied to the bonding film 3 in the first step, since the leaving group is difficult to be removed in the vicinity of the release surface, the state immediately after the film formation is easily maintained, and the adhesiveness is sufficiently latent. There is also an advantage of gaining. Therefore, by applying energy to the peeling surface, the peeling surface is firmly bonded to the second adherend 6. By using the bonding film transfer sheet 1a as described above, the bonding film 3 which is formed by a vapor deposition method and whose adhesion can be freely controlled can be handled like a double-sided tape. The adherend 5a and the second adherend 6 can be joined easily and firmly.

Further, the bonded interface in the obtained bonded body 10 is excellent in both airtightness and liquid tightness. This is because the bonding film 33 itself has a high density and low air permeability, and the bonding mechanism is based on the chemical bond as described above, so that the passage of small molecules is restricted. Therefore, when the joined body 10 is manufactured by setting the joining region so that a closed space is formed, the airtightness of the obtained closed space (for example, the closed space 34 in FIG. 2) is determined by the leak amount (leakage using helium gas). Rate) of 1 × 10 ⁻⁹ Pa · m ³ / sec or less. With such a leak amount, the hermeticity of the closed space can be maintained over a long period of time. Therefore, the present invention is effective when the closed space is maintained in a reduced pressure state or replaced with a predetermined gas. Used.
In addition, after obtaining the joined body 10, you may make it perform either one or both of the following two processes [4A] and [4B] with respect to this joined body 10 as needed.

[4A] The obtained bonded body 10 is pressurized in a direction in which the first adherend 5a and the second adherend 6 approach each other.
Thereby, the surface of the bonding film 33 is closer to the surfaces of the first adherend 5a and the second adherend 6, and the bonding strength in the bonded body 10 can be further increased.
At this time, the pressure at the time of pressurizing the bonded body 10 is preferably as high as possible. Thereby, the joint strength in the joined body 10 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 a constituent material and thickness of the 1st to-be-adhered body 5a or the 2nd to-be-adhered body 6, and a joining apparatus. Specifically, it is preferably about 1 MPa or more and 10 MPa or less, and more preferably about 1 MPa or more and 5 MPa or less.
The time for pressurization is not particularly limited, but is preferably about 10 seconds to 30 minutes.

[4B] The obtained bonded body 10 is heated.
Thereby, the joint strength in the joined body 10 can be further increased.
At this time, the temperature at which the joined body 10 is heated is not particularly limited as long as it is higher than room temperature and lower than the heat resistance temperature of the joined body 10, but is preferably about 25 ° C. or more and 100 ° C. or less, and more preferably 50 It is set to about 100 ° C. or higher. By heating at a temperature in such a range, it is possible to reliably increase the bonding strength while reliably preventing the bonded body 10 from being altered or deteriorated by heat.

Moreover, although heating time is not specifically limited, It is preferable that it is about 1 minute or more and 30 minutes or less.
Moreover, when performing both said process [4A] and [4B], it is preferable to perform these simultaneously. That is, it is preferable to heat the bonded body 10 while applying pressure. Thereby, the effect by pressurization and the effect by heating are exhibited synergistically, and the joint strength of the joined body 10 can be particularly increased.

In the case where the thermal expansion coefficients of the two adherends are substantially equal, it is preferable to heat the joined body 10 as described above, but the thermal expansion coefficients of the two adherends are greatly different from each other. For this, it is preferable to perform bonding at as low a temperature as possible. By performing the bonding at a low temperature, it is possible to further reduce the thermal stress generated at the bonding interface.
Specifically, although it depends on the difference in thermal expansion coefficient, it is preferable to heat at about 25 ° C. or more and 50 ° C. or less, and more preferably about 25 ° C. or more and 40 ° C. or less. In such a temperature range, even if the difference in thermal expansion coefficient is large to some extent (for example, 5 × 10 ⁻⁵ / K or more), the thermal stress generated at the bonding interface can be sufficiently reduced. As a result, it is possible to reliably prevent warpage, peeling, and the like in the joined body 10.
By performing the steps [4A] and [4B] as described above, the bonding strength of the bonded body 10 can be further improved.

(Joining equipment)
By the way, the joining method of the present invention as described above can be performed using the following joining apparatus.
7 and 8 are perspective views schematically showing the configuration of the joining device used in the first 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”.

A joining apparatus 500 illustrated in FIG. 7 includes a flat plate stage 501 and rollers 502 and 503 provided at both ends of the stage 501.
In addition, a sheet roll 510 obtained by winding the bonding film transfer sheet 1a in a roll shape is rotatably provided above the left side of the stage 501. The bonding film transfer sheet 1a is sequentially drawn from the sheet roll 510, and the fed bonding film transfer sheet 1a passes from the left end to the right end on the stage 501, and is provided below the right side of the stage 501. It is comprised so that it may be wound up with the wound winding roll 511 made.

Further, in the sheet roll 510, the bonding film transfer sheet 1a is wound so that the surface on which the bonding film 3 is provided faces upward.
A guide roll 512 and a guide roll 513 are provided on the right side of the sheet roll 510 and the left side of the take-up roll 511, respectively. Among these, the guide roll 512 changes the advancing direction of the bonding film transfer sheet 1a fed from the upper left side of the stage 501 toward the lower right side to the horizontal direction. On the other hand, the guide roll 513 changes the traveling direction of the bonding film transfer sheet 1 a traveling on the stage 501 from the left side to the right side so as to face the winding roll 511.
By the sheet roll 510, the take-up roll 511, the guide roll 512, and the guide roll 513 as described above, the bonding film transfer sheet 1a is conveyed from the left side to the right side along the upper surface of the stage 501.

Further, a plasma processing mechanism 520, a first adherend supply mechanism 530, a pressing mechanism 540, and a peeling mechanism 550 are sequentially provided between the guide roll 512 and the guide roll 513 from the left side.
The plasma processing mechanism 520 is provided above the stage 501 and can supply the plasma P toward the bonding film 3 of the bonding film transfer sheet 1a. Examples of such a mechanism include various atmospheric pressure plasma apparatuses such as the direct plasma system, the remote plasma system, and the downflow plasma system as described above. When the bonding film transfer sheet 1a passes between the plasma processing mechanism 520 and the stage 501, energy is applied to the bonding film 3 during the passage, and adhesiveness is developed.

  The bonding film transfer sheet 1a that has passed through the plasma processing mechanism 520 is conveyed to a first adherend supply mechanism 530 provided on the right side thereof. The first adherend supply mechanism 530 includes a manipulator (not shown) that holds the first adherend 5a and places it on the bonding film transfer sheet 1a from above. The first adherend 5a placed on the bonding film transfer sheet 1a is bonded to the bonding film transfer sheet 1a by the adhesiveness developed in the bonding film 3.

  The first adherend 5a bonded to the bonding film transfer sheet 1a is conveyed to the pressing mechanism 540 provided on the right side of the bonding film transfer sheet 1a as the bonding film transfer sheet 1a moves. The pressing mechanism 540 includes a pressing roller 541 and a pressing roller 542 provided above and below the stage 501. Between the two pressing rollers 541 and 542, the stage 501 and the bonding film transfer sheet 1a are located. The separation distance between the two pressing rollers 541 and 542 allows the first adherend 5a to be transferred to the bonding film. The distance is adjusted so that it can be pressed against the sheet 1a. By this pressing mechanism 540, the first adherend 5a and the bonding film transfer sheet 1a are more firmly bonded, and the first temporary bonded body 7 is obtained.

  The obtained first temporary joined body 7 is conveyed to the peeling mechanism 550 provided on the right side thereof with the movement of the bonding film transfer sheet 1a. The peeling mechanism 550 includes a guide roll 513 that changes the traveling direction of the bonding film transfer sheet 1a downward. By this peeling mechanism 550, the base material 2 a is forcibly peeled from the first temporary joined body 7. As a result, a part of the bonding film 3 is transferred to the first adherend 5a to obtain the second temporary bonded body 8, and the remaining bonding film 3 is wound around the winding roll 511 together with the substrate 2a. It is done.

The obtained second temporary joined body 8 is gripped by a gripping portion (not shown) and is subjected to a joining step with the second adherend 6 in the joining apparatus 600 shown in FIG.
A bonding apparatus 600 shown in FIG. 8 includes a plasma processing mechanism 610, a second adherend supply mechanism 620, and a pressing mechanism 630, which are sequentially provided from the left side.
The plasma processing mechanism 610 includes a base 611 on which the second temporary joined body 8 can be placed, and a plasma source 612 that performs plasma processing on the second temporary joined body 8. When the plasma P is generated from the plasma source 612, the bonding film 33 of the second temporary bonded body 8 is subjected to plasma processing. Thereby, energy is given to the bonding film 33 and adhesiveness is expressed.

The second temporary joined body 8 that has been subjected to the plasma treatment is conveyed to a second adherend supply mechanism 620 provided on the right side thereof. The second adherend supply mechanism 620 grips the second adherend 6 and places a manipulator (not shown) placed on the bonding film 33 of the second temporary bonded body 8 from above and an upper surface. And a base 621 on which the manipulator can be placed. The second adherend 6 placed on the second temporary joined body 8 is joined to the second temporary joined body 8 by the adhesiveness developed in the bonding film 33. As a result, the first adherend 5a and the second adherend 6 are bonded via the bonding film 33, and the bonded body 10 is obtained.
The obtained bonded body 10 is conveyed to the pressing mechanism 630. The pressing mechanism 630 includes a base 631 and a load generator (not shown) that is provided on the base 631 and presses the joined body 10. A pressing force is applied to the joined body 10 by the pressing mechanism 630, and the joined body 10 is more firmly joined.

Second Embodiment
Next, a second embodiment of the bonding film transfer sheet and the bonding method of the present invention will be described.
9 and 10 are views (longitudinal sectional views) for explaining a second embodiment of the bonding film transfer sheet and the bonding 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 second embodiment of the bonding film transfer sheet and the bonding method will be described, but differences from the first embodiment will be mainly described, and description of similar matters will be omitted. In the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals as those of the components described above, and detailed description thereof is omitted.
This embodiment is the same as the first embodiment except that the shape of the bonding film transfer sheet is different.

A bonding film transfer sheet 1b shown in FIG. 9 has a base material 2b and a bonding film 3 formed on the base material 2b, and transfers the bonding film 3 to the first adherend 5b. It is used as such.
The base material 2b has peeling with respect to the joining film | membrane 3, and has the convex part 21 on the upper surface. This convex portion 21 is for selectively applying a pressing force to a partial region 32 of the bonding film 3, similarly to the convex portion 51 in the first embodiment.

The upper surface of the convex portion 21 is preferably a flat surface, and the cross-sectional shape of the convex portion 21 is preferably trapezoidal or rectangular. Thereby, the convex part 21 can press a part of the bonding film 3 uniformly and accurately. Moreover, the height of the convex part 21 is not specifically limited, It sets similarly to the height of the convex part 51 mentioned above.
Moreover, the bonding film 3 is provided so as to cover the upper surface of the base material 2b having such a convex portion 21. As a result, the bonding film 3 is provided along a concavo-convex shape including the convex portion 21, and thus a step reflecting the shape of the convex portion 21 is formed on the upper surface of the bonding film 3.
Such a substrate 2b is preferably rigid. Thus, the convex portion 21 is prevented from being deformed when the laminated body formed by laminating the bonding film transfer sheet 1b and the first adherend 5b is pressed. As a result, it is possible to reliably prevent the shape of the transferred bonding film 33 from being deformed and to perform accurate bonding.

Next, a method for manufacturing a bonded body 10 formed by bonding the first adherend 5b and the second adherend 6 using the bonding film transfer sheet 1b will be described.
Similar to the first embodiment, the bonding method according to the present embodiment imparts energy to the upper surface (surface) of the bonding film 3 of the bonding film transfer sheet 1b, and the bonding film 3 and the first adherend 5b. The first step is to laminate the bonding film transfer sheet 1b and the first adherend 5b so that the first temporary bonded body 7 is obtained, and the first temporary bonded body 7 to the substrate 2b. The second step of transferring a part of the bonding film 3 to the first adherend 5b to obtain the second temporary bonded body 8 and the bonding film 33 of the second temporary bonded body 8 are peeled off. The second temporary bonding body 8 and the second adherend 6 are laminated so that the bonding film 33 and the second adherend 6 are in close contact with each other while applying energy to the upper surface (peeling surface) of the film. And a third step of obtaining the joined body 10. Hereinafter, each process will be described sequentially.

[1] First, a bonding film transfer sheet 1b is prepared (see FIG. 9A).
Next, energy is applied to the upper surface 31 of the bonding film 3 of the bonding film transfer sheet 1b. As a result, adhesiveness develops on the upper surface 31 of the bonding film 3.
Here, a case where a pressing force is applied to the region 32 of the bonding film 3 where the convex portions 21 are provided will be described.

  Specifically, a first adherend 5b is prepared, and as shown in FIG. 9B, the bonding film transfer sheet 1b and the first adherend 5b are arranged so that the bonding film 3 and the first adherend 5b are in contact with each other. One adherend 5b is laminated. And the obtained laminated body is pressed in the thickness direction (the direction in which the base material 2b and the first adherend 5b approach) (first step). Thereby, the convex portion 21 selectively presses a part of the bonding film 3, and a pressing force is selectively applied to the region 32 of the bonding film 3. As a result, the first temporary joined body 7 in which the region 32 is partially joined is obtained (see FIG. 9C).

Although the first adherend 5b shown in FIG. 9B has a flat plate shape, the shape is not particularly limited as long as it has a flat surface that comes into contact with the bonding film 3.
The first adherend 5b is preferably flexible. Thereby, when the laminated body is pressed, the shape followability of the first adherend 5b is improved, so that the adhesion between the bonding film transfer sheet 1b and the first adherend 5b can be further improved.

[2] Next, as shown in FIG. 9D, the first adherend 5b is peeled off from the first temporary joined body 7 (second step). Thereby, the interface between a part of the bonding film 3 (bonding film 33) and the base material 2b is peeled off, and the second temporary bonded body 8 obtained by transferring the bonding film 33 to the first adherend 5b is obtained. (See FIG. 10E).
In this peeling, a portion of the bonding film 3 corresponding to the convex portion 21 of the substrate 2b is transferred to the first adherend 5b, and the remaining portion of the bonding film 3 is transferred together with the substrate 2b without being transferred. Remains. Therefore, the second temporary bonded body 8 has the first adherend 5b and the bonding film 33 partially transferred. By using the bonding film transfer sheet 1b in this manner, the bonding film 3 can be efficiently and simply patterned simply by appropriately selecting the shape of the convex portion 21 of the substrate 2b.
In addition, the upper surface of the obtained bonding film 33 becomes a peeling surface peeled from the base material 2b.

[3] Next, energy is applied to the upper surface (peeling surface) of the bonding film 33 of the second temporary bonded body 8.
Specifically, first, a second adherend 6 is prepared.
Next, energy is applied to the upper surface of the bonding film 33 in the same manner as in the first embodiment.
Specifically, as shown in FIG. 10 (f), the second temporary bonded body 8 and the second adherend 6 are laminated so that the bonding film 33 and the second adherend 6 are in contact with each other. To do. Then, the obtained laminated body is pressed in the thickness direction (the direction in which the second temporary bonded body 8 and the second adherend 6 approach each other) (third step). As a result, a pressing force is applied to the bonding film 33, and the bonded body 10 formed by bonding the first adherend 5b and the second adherend 6 through the bonding film 33 is obtained (FIG. 10 (g)).
Also in the present embodiment as described above, the same operations and effects as in the first embodiment can be obtained.

Moreover, in this embodiment, since the convex part 21 is provided in the base material 2b, what has flexibility can also be used as the 1st to-be-adhered body 5b. Therefore, this embodiment is suitable for transferring the bonding film 33 to the first adherend 5b having flexibility.
By the way, the joining method of the present invention as described above can be performed using the joining apparatus 700 shown in FIG. 11 and the joining apparatus 600 shown in FIG.

FIG. 11 is a perspective view schematically showing a configuration of a joining apparatus used in the second embodiment of the joining method of the present invention. In the following description, the upper side in FIG. 11 is referred to as “upper” and the lower side is referred to as “lower”.
A bonding apparatus 700 illustrated in FIG. 11 includes a plasma processing mechanism 710, a first adherend supply mechanism 720, a pressing mechanism 730, and a peeling mechanism 740, which are sequentially provided from the left side.

The plasma processing mechanism 710 includes a base 711 on which the bonding film transfer sheet 1b can be placed, and a plasma source 712 that performs plasma processing on the bonding film transfer sheet 1b. When the plasma P is generated from the plasma source 712, the plasma processing is performed on the bonding film 3 of the bonding film transfer sheet 1b. Thereby, energy is given to the bonding film 3 and adhesiveness is expressed.
The bonding film transfer sheet 1 b that has been subjected to the plasma treatment is then conveyed to the first adherend supply mechanism 720. The first adherend supply mechanism 720 grips the first adherend 5b and places a manipulator (not shown) placed on the bonding film 3 of the bonding film transfer sheet 1b from above and a manipulator on the upper surface. And a mountable base 721. The first adherend 5b placed on the bonding film transfer sheet 1b is bonded to the bonding film transfer sheet 1b by the adhesiveness developed in the bonding film 3. As a result, the first adherend 5b and the bonding film transfer sheet 1b are bonded via the bonding film 3, and the first temporary bonded body 7 is obtained.

The obtained first temporary joined body 7 is conveyed to the pressing mechanism 730. The pressing mechanism 730 includes a base 731 and a load generator 732 that is provided on the base 731 and presses the first temporary joined body 7. A pressing force is applied to the first temporary joined body 7 by the pressing mechanism 730, and the joining of the first temporary joined body 7 becomes stronger.
Thereafter, the first temporary joined body 7 is conveyed to the peeling mechanism 740. The peeling mechanism 740 includes a base 741 and a manipulator (not shown) that is provided on the base 741 and peels the first adherend 5b upward from the first temporary joined body 7. . By this peeling mechanism 740, the first adherend 5b is forcibly peeled from the first temporary joined body 7. As a result, a part of the bonding film 3 is transferred to the first adherend 5b to obtain the second temporary bonded body 8, and the remaining bonding film 3 remains on the substrate 2b.

The obtained second temporary joined body 8 is gripped by a gripping section (not shown), and is subjected to a joining process with the second adherend 6 in the joining apparatus 600 shown in FIG. 8 described above.
The joining method of the present invention as described above is used to join various members.
Specifically, semiconductor elements such as transistors, diodes and memories, piezoelectric elements such as crystal oscillators, reflectors, optical lenses, diffraction gratings, optical elements such as optical filters, and photoelectric conversion elements such as solar cells , Semiconductor substrates and semiconductor elements mounted on them, insulating substrates and wiring or electrodes, inkjet recording heads, microreactors, microelectromechanical systems (MEMS) components such as micromirrors, sensors such as pressure sensors and acceleration sensors Parts, semiconductor element and electronic component package parts, magnetic recording medium, magneto-optical recording medium, recording medium such as optical recording medium, liquid crystal display element, organic EL element, electrophoretic display element parts, fuel When joining battery parts or the like, the joining method of the present invention is applicable.

As described above, the bonding film transfer sheet and the bonding method of the present invention have been described based on the illustrated embodiments, but the present invention is not limited thereto.
For example, in each of the embodiments, the bonding film is provided so as to cover the entire upper surface of the base material, but the bonding film may be patterned into a predetermined shape.
Moreover, in the joining method of this invention, it is not limited to the structure of the said embodiment, The process for arbitrary objectives may be added 1 or 2 or more.

Next, specific examples of the present invention will be described.
1. Manufacture of joined body (Example 1)
<1> First, a polyethylene film having a width of 50 mm, a length of 100 mm, and an average thickness of 100 μm was prepared as a base material. The surface energy of polyethylene is 31 mN / m.

In addition, as a first adherend, a frame-shaped member (made of OA10 glass) having a length of 20 mm × width of 20 mm × height of 5 mm, and one surface of the frame-shaped member are closed, 20 mm long × 20 mm wide × average thickness A member prepared by previously bonding a 1 mm substrate (made of OA10 glass) was prepared. The frame width of the frame-shaped member was 2 mm. That is, the first adherend is a container-like member having an opening of 16 mm length × 16 mm width on one surface side. The surface energy of OA10 glass is 300 mN / m.
Furthermore, a plate member (made of OA10 glass) having a length of 20 mm × width of 20 mm × average thickness of 1 mm was prepared as a second adherend. In addition, the 2nd to-be-adhered body is provided with the through-hole with an internal diameter of 2 mm so that the center part may be penetrated. This through-hole is used when evaluating the leak amount inside the joined body after the joined body is manufactured.

<2> Next, a plasma polymerization film having an average thickness of 200 nm was formed on the substrate by the plasma polymerization apparatus 100 shown in FIG. The film forming conditions are as shown below.
<Film formation conditions>
-Source gas composition: Octamethyltrisiloxane-Source gas flow rate: 50 sccm
Carrier gas composition: Argon Carrier gas flow rate: 100 sccm
・ High frequency power output: 100W
・ High frequency output density: 25 W / cm ²
-Chamber pressure: 1 Pa (low vacuum)
・ Processing time: 15 minutes ・ Substrate temperature: 20 ° C.

Thereby, a plasma polymerization film was formed on the substrate. And the joining film transfer sheet which consists of two layers of a base material and a plasma polymerization film | membrane was obtained.
The plasma polymerized film thus formed is composed of a polymer of octamethyltrisiloxane (raw material gas), and includes a Si skeleton including a siloxane bond and a random atomic structure, and an alkyl group (desorbed). Group). Further, in order to measure the crystallinity of the Si skeleton, a part of the plasma polymerized film was irradiated with ultraviolet rays having a wavelength of 405 nm for 600 seconds, and then the crystallinity was measured by an X-ray diffraction method. As a result, the crystallinity of the plasma polymerized film was 30% or less.

<3> Next, each plasma polymerization film obtained was subjected to plasma treatment under the following conditions.
<Plasma treatment conditions>
・ Plasma treatment method: Direct plasma method ・ Process gas composition: Helium gas ・ Atmospheric pressure: Atmospheric pressure (100 kPa)
・ Distance between electrodes: 1mm
・ Applied voltage: 1 kVp-p
-Voltage frequency: 40 MHz

<4> Next, the base material and the first adherend were laminated so that the plasma polymerized film and the frame-shaped member were in contact with each other one minute after the plasma treatment. The obtained laminate was pressed at 5 MPa. Thereby, a base material and the 1st to-be-adhered body were joined, and the 1st temporary joining body was obtained.
<5> Next, the base material was peeled off from the first temporary joined body. As a result, the portion of the plasma polymerized film that was in contact with the first adherend remained on the first adherend side and could be transferred. Thereby, the 2nd temporary joined body which consists of a 1st to-be-adhered body and a plasma polymerization film | membrane adhering to this was obtained.

<6> Next, plasma treatment was performed on the plasma polymerization film of the second temporary joined body in the same manner as in <3>.
<7> Next, one minute after the plasma treatment was performed, the second temporary bonded body and the second adherend were laminated so that the plasma polymerized film and the second adherend were in contact with each other. The obtained laminate was pressed at 5 MPa. Thereby, the 2nd temporary joined body and the 2nd to-be-adhered body were joined, and the joined body was obtained.

(Example 2)
First, a plasma polymerization film was formed on a substrate in the same manner as in Example 1.
Next, a polypropylene film (cover sheet) having the same size as the substrate and an average thickness of 100 μm was prepared. And the base material and the cover sheet were laminated | stacked so that a plasma polymerization film | membrane and a cover sheet might contact, and it pressed with the laminating apparatus. As a result, a bonding film transfer sheet composed of three layers of a base material, a plasma polymerized film, and a cover sheet was obtained. The surface energy of polypropylene is 23 mN / m.
The obtained bonding film transfer sheet was left in the atmosphere for 100 hours, and then the first adherend and the second adherend were bonded in the same manner as in Example 1 to obtain a bonded body.

(Example 3)
A joined body was obtained in the same manner as in Example 1 except that the base material was changed to a polyethylene terephthalate (PET) film having a width of 50 mm, a length of 100 mm, and an average thickness of 100 μm. The surface energy of polyethylene terephthalate is 43 mN / m.
Example 4
A joined body was obtained in the same manner as in Example 1 except that the base material was changed to a polytetrafluoroethylene (PTFE) film having a width of 50 mm, a length of 100 mm, and an average thickness of 100 μm. The surface energy of polytetrafluoroethylene is 18 mN / m.

(Example 5)
A joined body was obtained in the same manner as in Example 1 except that the base material was changed to a polyimide film having a width of 50 mm, a length of 100 mm, and an average thickness of 50 μm. The surface energy of polyimide is 50 mN / m.
(Example 6)
As a base material, a frame member (made of polyethylene) having a length of 20 mm × width 20 mm × height 0.5 mm and a substrate (polyethylene 20 mm × width 20 mm × average thickness 1 mm) covering one surface of the frame member A joined body was obtained in the same manner as in Example 1 except that a member obtained by joining in advance was used.
That is, a plasma polymerization film was formed so as to cover the frame member of the above member. Thus, a bonding film transfer sheet was obtained, and a bonded body was obtained using this bonding film transfer sheet.

(Comparative Example 1)
First, a bonding film transfer sheet was obtained in the same manner as in Example 1 except that a paper tape having a width of 50 mm, a length of 100 mm, and an average thickness of 0.12 mm was used as the substrate.
Next, plasma treatment is performed on the plasma polymerized film in the same manner as in Example 1, and the base material and the first adherend are laminated so that the plasma polymerized film and the frame member of the first adherend are in contact with each other. did. The obtained laminate was pressed at 5 MPa. Thereby, a base material and the 1st to-be-adhered body were joined, and the 1st temporary joining body was obtained.

Subsequently, when the base material was peeled off from the first temporary joined body, a part of the plasma polymerized film was peeled off while being attached to the base material side. In addition, a spot-like plasma polymerization film remained partially on the first adherend side.
From the above, in Comparative Example 1, the plasma polymerization film could not be transferred from the bonding film transfer sheet to the first adherend side.

(Comparative Example 2)
A bonding film transfer sheet was obtained in the same manner as in Example 6 except that the material of the substrate was changed from polyethylene to OA glass.
Next, plasma treatment is performed on the plasma polymerized film in the same manner as in Example 6, and the base material and the first adherend are laminated so that the plasma polymerized film and the frame member of the first adherend are in contact with each other. did. The obtained laminate was pressed at 5 MPa. Thereby, a base material and the 1st to-be-adhered body were joined, and the 1st temporary joining body was obtained.

Subsequently, when the base material was peeled off from the first temporary joined body, a part of the plasma polymerized film was peeled off while being attached to the base material side. In addition, a spot-like plasma polymerized film partially remained on the first adherend side.
From the above, in Comparative Example 2, the plasma polymerization film could not be transferred from the bonding film transfer sheet to the first adherend side.
(Comparative Example 3)
The first adherend and the second adherend were bonded with an epoxy adhesive to obtain a joined body. The average thickness of the epoxy adhesive was 200 μm.

2. 2. Evaluation of Bonded Body 2.1 Evaluation of Bonding Strength Bonding strength was measured for each of the bonded bodies obtained in each Example and each Comparative Example.
The measurement of the bonding strength was performed by measuring the tensile force immediately before peeling when the first adherend and the second adherend were forcibly peeled off in each joined body. Further, the measurement of the bonding strength was performed immediately after the bonding and after the temperature cycle from −40 ° C. to 125 ° C. was repeated 50 times after the bonding.

As a result, the joined body obtained in each example had sufficient joining strength (10 MPa or more) immediately after joining and after the temperature cycle.
On the other hand, the bonding strength could not be measured for Comparative Examples 1 and 2 among the bonded bodies obtained in the respective Comparative Examples. Moreover, about the comparative example 3, although it had sufficient joining strength (10 Mpa or more) immediately after joining, joining strength fell after the temperature cycle.

2.2 Evaluation of leak amount The leak amount was measured for each of the joined bodies obtained in each of the examples and the comparative examples.
The leak amount was measured by a vacuum method using a leak detector. Helium gas was used as the probe gas.
Further, the amount of leakage was measured immediately after bonding and after the temperature cycle of 2.1.
As a result, in the joined body obtained in each example, the leak amount was less than 1 × 10 ⁻⁹ Pa · m ³ / sec immediately after joining and after the temperature cycle.

On the other hand, the leakage amount could not be measured for Comparative Examples 1 and 2 among the joined bodies obtained in the respective Comparative Examples. In Comparative Example 3, the amount of leakage was very large immediately after bonding, and was 1 × 10 ⁻⁶ Pa · m ³ / sec or more.
From the above evaluation results, it was revealed that the joined bodies obtained in each Example were excellent in joining strength and airtightness even after undergoing a temperature cycle.

DESCRIPTION OF SYMBOLS 1a, 1b .. Bonding film transfer sheet 2a, 2b ... Base material 21 ... Convex part 3, 33 ... Bonding film 301 ... Si skeleton 302 ... Siloxane bond 303 ... Leaving group 304 ... Active hand 31 ... Upper surface 32 ... Region 34 ... Closed space 35 ... Surface 5a, 5b ... First adherend 51 ... Convex part 6 ... Second adherend 7 ... First temporary joined body 8 …… Second Temporary Assembly 100 …… Plasma Polymerization Device 101 …… Chamber 102 …… Grounding Wire 103 …… Supply Port 104 …… Exhaust Port 130 …… First Electrode 139 …… Electrostatic Chuck 140 …… Second electrode 170 ... Pump 171 ... Pressure control mechanism 180 ... Power supply circuit 182 ... High frequency power supply 183 ... Matching box 184 ... Wiring 190 ... Gas supply part 191 ... Liquid storage part 192 ... Vaporization 193 ... Gas cylinder 194 ... Piping 195 ... Diffusion plate 500 ... Joining device 501 ... Stage 502, 503 ... Roller 510 ... Sheet roll 511 ... Winding roll 512, 513 ... Guide roll 520 ... Plasma processing mechanism 530... First adherend supply mechanism 540... Pressing mechanism 541, 542... Pressing roller 550... Peeling mechanism 600. Plasma source 620 ... second adherend supply mechanism 621 ... base 630 ... pressing mechanism 631 ... base 700 ... joining apparatus 710 ... plasma processing mechanism 711 ... base 712 ... plasma source 720 …… First adherend supply mechanism 721 …… Base 730 …… Pressing mechanism 731 …… Base 73 2 …… Load generator 740 …… Peeling mechanism 741 …… Base P …… Plasma

Claims (26)

A bonding film transfer sheet used to transfer a bonding film to an adherend,
A substrate;
A bonding film provided on one surface of the substrate;
The base material and the bonding film have peelability,
The bonding film includes a Si skeleton having an atomic structure including a siloxane (Si—O) bond, and a leaving group bonded to the Si skeleton and including an organic group.
The bonding film imparts energy to at least a part of the bonding film, and bonds to the adherend using the adhesiveness developed in the bonding film when the leaving group is released from the Si skeleton. And a bonding film transfer sheet that can be peeled off at the interface with the substrate.   2. The junction according to claim 1, wherein a sum of a content ratio of Si atoms and a content ratio of O atoms is 10 atomic% or more and 90 atomic% or less among atoms obtained by removing H atoms from all atoms constituting the bonding film. Membrane transfer sheet.   The bonding film transfer sheet according to claim 1 or 2, wherein an abundance ratio of Si atoms and O atoms in the bonding film is 3: 7 or more and 7: 3 or less.   The bonding film transfer sheet according to any one of claims 1 to 3, wherein the crystallinity of the Si skeleton is 45% or less.   The bonding film transfer sheet according to claim 1, wherein the bonding film contains Si—H bonds.   In the infrared absorption spectrum of the bonding film including the Si—H bond, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the Si—H bond is 0.001 or more and 0.2 or less. The bonding film transfer sheet according to claim 5.   The bonding film transfer sheet according to claim 1, wherein the leaving group is an alkyl group.   In the infrared absorption spectrum of the bonding film containing a methyl group as the leaving group, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the methyl group is 0.05 to 0.45. The bonding film transfer sheet according to claim 7.   The bonding film transfer sheet according to claim 8, wherein the bonding film is made of polyorganosiloxane.   The bonding film transfer sheet according to claim 9, wherein the polyorganosiloxane contains a polymer of octamethyltrisiloxane as a component.   The bonding film transfer sheet according to claim 1, wherein the bonding film is formed by plasma polymerization. The bonding film transfer sheet according to claim 11, wherein in the plasma polymerization, a high-frequency power density when generating plasma is 0.01 W / cm ² or more and 100 W / cm ² or less.   The bonding film transfer sheet according to claim 1, wherein an average thickness of the bonding film is 1 nm or more and 1000 nm or less.   The bonding film transfer sheet according to claim 1, wherein the bonding film is a solid material having no fluidity.   The bonding film transfer sheet according to claim 1, wherein the substrate has flexibility.   The bonding film transfer sheet according to claim 15, wherein the substrate is made of a resin material.   The bonding film transfer sheet according to claim 16, wherein the resin material is any one of fluorine-based resin, polyolefin, polyester, and polyimide.   The bonding film transfer sheet according to any one of claims 1 to 17, wherein the substrate has a surface energy smaller than that of the adherend.   The bonding film transfer sheet according to any one of claims 1 to 18, wherein the surface energy of the base material is 5 mN / m or more and 200 mN / m or less.   The bonding film transfer according to claim 1, wherein the base material has a convex portion on a part of a surface, and the bonding film is formed so as to cover the surface. Sheet.   21. The bonding film transfer sheet according to claim 1, further comprising a cover sheet that covers a surface of the bonding film.   The bonding film transfer sheet according to claim 21, wherein the cover sheet has a surface energy smaller than that of the substrate. A bonding method for bonding the adherend and another adherend using the bonding film transfer sheet according to any one of claims 1 to 22,
Energy is applied to the surface of the bonding film of the bonding film transfer sheet, the leaving group is desorbed from the Si skeleton, and adhesiveness is exhibited, so that the surface of the bonding film and the adherend are in close contact with each other. A first step of stacking the bonding film transfer sheet and the adherend to obtain a first temporary bonded body,
A second step of peeling the base material from the first temporary bonded body, transferring the bonding film to the adherend, and obtaining a second temporary bonded body;
Energy is imparted to the release surface of the bonding film of the second temporary bonded body, the leaving group is released from the Si skeleton, and the adhesiveness is exhibited, and the release surface of the bonding film and the other covered surface are exposed. A bonding method comprising: a third step of stacking the second temporary bonded body and the other adherend to obtain a bonded body so that the bonded body is in close contact with the bonded body.   24. The joining method according to claim 23, wherein the application of energy in the first step is performed by a method of applying a pressing force to the first temporary joined body so that the base material and the adherend are close to each other.   The joining method according to claim 24, wherein the pressing force is 0.2 MPa or more and 10 MPa or less.   The adherend has a convex portion on a part of its surface, and the bonding film transfer sheet and the adherend are disposed so that the convex portion and the bonding film are in close contact with each other in the first step. In the second step, the bonding film in the portion in contact with the convex portion is selectively transferred, and in the third step, the adherend and the other adherend are The joining method according to any one of claims 23 to 25, wherein the parts are joined partially.

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