TW201947318A - Photosensitive film laminate and cured product thereof and electronic component suppressing peeling of plating or the like in a vicinity of the hollow structure in an electronic component having a hollow structure such as a SAW filter - Google Patents

Abstract

This invention provides a photosensitive film laminate suitable for forming a hollow structure, which can suppress peeling of plating or the like in a vicinity of the hollow structure in an electronic component having a hollow structure such as a SAW filter. The photosensitive film laminate comprises a support film, a photosensitive film formed of a photosensitive composition, and a protective film in this order, wherein if the protective film is peeled from the photosensitive film laminate to expose the photosensitive film surface in a condition that the arithmetic average surface roughness of the photosensitive film surface after leaving for 1 minute in an environment of 23 DEG C and a relative humidity of 42% is Ra1, and if the protective film is peeled from the photosensitive film laminate to expose the photosensitive film surface in a condition that the arithmetic average surface roughness of the photosensitive film surface after leaving for 180 minutes in an environment of 23 DEG C and a relative humidity of 42% is Ra2, the formula below is satisfied: Ra1 ≥ 0.10um and 0.40 ≤ Ra2/Ra1 < 1.00.

Description

Photosensitive film laminate and its cured product, and electronic parts

The present invention relates to a photosensitive thin film laminate, and more specifically relates to a photosensitive thin film laminate, a hardened product thereof, and an electronic part which are applicable to the formation of the hollow structure for electronic parts having a hollow structure.

In recent years, the requirements for miniaturization and high functionality of electronic devices have been increasing, and the electronic components used there have also been required to be smaller, thinner, and more functionally combined. Among them, image sensors are also represented by CMOS and CCD sensors, or gyro sensors based on MEMS (Micro Electro Mechanical Systems) technology that integrates mechanical elements and electronic circuit elements on a substrate through semiconductor microfabrication technology. Surface acoustic wave (SAW) filters have attracted attention as a representative of the development of fine electronic components such as the formation of electrode patterns or fine structures on the surface of single crystal wafers, and packaging of components that can perform specific electrical functions. For these fine electronic parts, if you do not want to contact other objects on the active surface (movable part) of the sensor element, and you want to protect the sensor element with moisture or dust to form a hollow structure, make the structure in which the sensor is placed.

The above-mentioned electronic parts are formed by hollow structures processed and bonded by conventional inorganic materials. However, methods that require reduction in manufacturing costs or further miniaturization, and use of photosensitive resins instead of inorganic materials to form hollow structures are beginning to be reviewed, such as laminating permanent resists, and using photolithography techniques. A hollow structure forming a wall portion (wall surface) or a cover portion (for example, WO2009 / 151050).

However, an electronic component having a hollow structure such as the SAW filter is intended to be actually mounted on a mounting substrate, and thus is manufactured as a package structure in which a wiring electrode having a piezoelectric substrate and an external terminal or an external electrode for electrical connection are electrically connected. At this time, in the vicinity of the wall portion or the cover portion forming the hollow structure, in order to obtain connection reliability with external wiring, an internal conductor is formed by a plating method or the like. In addition, in order to improve the protection and handling of the device at the same time, the hollow structure or the adjacent portion is resin-sealed by a transfer molding method or the like.

However, when a hollow structure is formed with a permanent resist, if internal conductors are formed in adjacent portions, peeling such as plating may occur, and it has been confirmed that the sealing material peels off from the surface of the wall portion or cover portion of the hollow structure.

Accordingly, the present invention provides a photosensitive thin film laminate suitable for forming a hollow structure for electronic parts having a hollow structure such as a SAW filter, which can suppress peeling of plating or the like in a neighboring portion of the hollow structure. Another object of the present invention is to provide a cured product formed using the photosensitive thin film laminate and an electronic component having a hollow structure.

As a method for forming the above-mentioned hollow structure by using a resin, a photosensitive film is laminated in several layers to be exposed, and a wall portion is formed by development, and another photosensitive film is placed on the upper end of the wall portion. The cover is formed in a predetermined shape, exposed and developed, and a hollow structure is formed by thermally curing the photosensitive resin. The present inventors have conducted a detailed review of the above-mentioned problems, and found that when a hollow structure is formed using the photosensitive film as described above, a wall portion or a lid portion constituting the hollow structure slightly remains in the developing solution used in the developing step. The developing solution oozes from the interface, and the adhesion with the plating is hindered, and it becomes easy to peel off. As a result of further review, it was found that for a photosensitive film laminate having a protective film, the surface morphology of the photosensitive film laminate after peeling the protective film and exposing the surface of the photosensitive film changes over time. By using a specific range of the photosensitive film laminate in When the hollow structure is formed, the obstacle of adhesion with plating or the like can be suppressed, and an electronic component having a high-quality hollow structure can be manufactured.

The present invention is as follows.
[1] A photosensitive film laminate comprising a support film, a photosensitive film formed of a photosensitive composition and a protective film in this order, and a photosensitive film laminate comprising a photosensitive film layer The arithmetic average surface roughness of the surface of the photosensitive film after peeling the protective film to expose the surface of the photosensitive film and leaving it at 23 ° C and 42% relative humidity for 1 minute is set to Ra1,
The arithmetic mean surface roughness of the surface of the photosensitive film after the protective film was peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and left to stand in an environment of 23 ° C. and a relative humidity of 42% for 180 minutes was set to Ra2
, The following formula is satisfied:
Ra1 ≧ 0.10 μm and 0.40 ≦ Ra2 / Ra1 <1.00.
[2] The photosensitive film laminate according to [1], wherein the protective film is peeled off from the photosensitive film laminate to expose the surface of the photosensitive film, and it is left for 1 minute in an environment of 23 ° C and a relative humidity of 42%. The maximum height of the surface of the aforementioned photosensitive film is set to Ry1,
The maximum height of the surface of the photosensitive film after the protective film was peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and left to stand in an environment of 23 ° C. and a relative humidity of 42% for 180 minutes was set to Ry2
, The following formula is satisfied:
Ry1 ≧ 1.00 μm and 0.30 ≦ Ry2 / Ry1 <1.00.
[3] The photosensitive film laminate according to [1], wherein the photosensitive composition contains a photocurable compound.
[4] The photosensitive film laminate according to [1], wherein the photosensitive composition further contains a photopolymerization initiator.
[5] The photosensitive thin film laminate according to [1], which is used for forming a cover portion or a wall portion constituting the hollow structure in an electronic component having a hollow structure.
[6] A cured product obtained by curing the photosensitive film of the photosensitive film laminate according to any one of [1] to [5].
[7] An electronic part characterized by having a hardened body as in [6].
[8] The electronic component according to [7], which has a hollow structure formed of a wall portion and a cover portion, and either or both of the wall portion and the cover portion are formed of the hardened material.

According to the present invention, there is provided a photosensitive thin film laminated body capable of suppressing peeling of plating or the like in an adjacent portion of a hollow structure for an electronic part having a hollow structure, and suitable for forming a hollow structure. Moreover, according to another aspect of this invention, the hardened | cured material formed using the said photosensitive thin film laminated body, and an electronic component can be provided.

Implementation of the invention

<Photosensitive film laminate>
The photosensitive film laminate of the present invention includes a support film, a photosensitive film formed of a photosensitive composition, and a protective film in this order. Hereinafter, each component which comprises the photosensitive film laminated body of this invention is demonstrated. In addition, if there is no special description, in this specification, the numerical range represented by the symbol "~" means the range containing the upper limit and the lower limit (namely, the range above the lower limit and below the upper limit).

[Support film]
The support film constituting the photosensitive film laminate of the present invention is a one that supports the photosensitive film, as long as the function can be achieved, and a publicly known one can be used without special restrictions. For example, polyethylene terephthalate or Polyethylene naphthalate and other polyester films, polyimide film, polyimide film, polypropylene film, polystyrene film and other thermoplastic resins are preferred. When the thermoplastic resin film is used, a filler (kneading treatment), a matte coating (coating treatment) treatment may be added to the resin applied to the film during film formation, and the film may be processed. The surface is treated by blasting, such as sandblasting, hairline processing, or chemical etching. Among these, polyester films can be suitably used from the viewpoints of heat resistance, mechanical strength, and handling properties. The supporting film may be a single layer, or two or more layers may be laminated.

As described above, for the purpose of improving the strength of the thermoplastic resin film, it is preferable to use a film extending in one or two axial directions.

In addition, for the purpose of improving the strength of the thermoplastic resin film described above, it is preferable to use a film extending in one or two axial directions.

The thickness of the supporting film is not particularly limited, but is appropriately selected depending on the application in a range of approximately 10 μm to 3,000 μm.

[Photosensitive film]
The photosensitive film constituting the photosensitive film laminate of the present invention is formed of a photosensitive composition. That is, a photosensitive composition containing each of the components described below can be applied to one side of the support film and dried to form a photosensitive composition. The photosensitive film is cured by exposing and developing the photosensitive film into a predetermined shape, and then curing the photosensitive composition. Therefore, in a state where the surface of the photosensitive film from which the protective film is peeled from the photosensitive film laminate is exposed, the surface composition of the photosensitive film changes over time because the photosensitive composition is in an uncured state. . With regard to the present invention, it has been found that there is a certain relationship between the change in the surface morphology of the photosensitive film and the peeling off of plating and the like. Only by being a photosensitive film laminate that satisfies the following conditions, and the hollow of electronic parts The structure may be formed by using a photosensitive thin film laminate, and it is an electronic component having a high-quality hollow structure in which the barrier to adhesion such as plating can be suppressed, and the structure can be suppressed.

In the present invention, the protective film is peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and the photosensitive film is left to stand for one minute in an environment of 23 ° C and a relative humidity of 42%. The maximum height of the surface is Ry1,
The arithmetic mean surface roughness of the surface of the photosensitive film after the protective film was peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and left to stand in an environment of 23 ° C. and a relative humidity of 42% for 180 minutes was set to For Ra2, it is important to satisfy the following formula;
Ra1 ≧ 0.10 μm and 0.40 ≦ Ra2 / Ra1 <1.00.
When the photosensitive film when the protective film is peeled is a concave-convex surface having a predetermined arithmetic average surface roughness, the concave-convex surface tends to gradually become a flat state, and the surface morphology changes over time. In the present invention, the change in the surface morphology over time is noticeable. By using a photosensitive film remaining on a specific surface morphology change, peeling of plating or the like in the adjacent portion of the hollow structure can be suppressed.

In the present invention, the arithmetic average surface roughness Ra1 of the photosensitive film in contact with the protective film after the protective film is peeled off is 0.10 μm or more, preferably 0.15 μm or more, and more preferably 0.20 μm or more. When there is an upper limit, it is preferably 1.00 μm or less, more preferably 0.80 μm or less, and even more preferably 0.60 μm or less. In addition, Ra1 is defined as a value measured after the protective film is peeled to expose the surface of the photosensitive film, and left to stand in an environment of 23 ° C. and a relative humidity of 42% for 1 minute.

From the viewpoint that peeling such as plating can be further suppressed, the maximum height Ry1 of the photosensitive film on the surface in contact with the protective film after peeling the protective film is preferably 1.00 or more, and more preferably 1.20 μm or more. Preferably, it is more preferably 1.40 μm or more. When an upper limit is set, it is preferably 5.00 μm or less, more preferably 4.00 μm or less, and even more preferably 3.00 μm or less. In addition, Ry1 is defined as a value measured after the protective film is peeled to expose the surface of the photosensitive film, and left to stand in an environment at 23 ° C. and a relative humidity of 42% for 1 minute.

The change in the shape of the surface of the photosensitive film over time can be evaluated by the ratio of the arithmetic average surface roughness after the protection film is peeled off (i.e., Ra1) from the arithmetic average surface roughness after a predetermined time has elapsed. . In the present invention, the photosensitive film is peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and the surface is in contact with the protective film after being left for 180 minutes in an environment of 23 ° C and 42% relative humidity. When the arithmetic average surface roughness of is set to Ra2, if a photosensitive film laminate that satisfies 0.40 ≦ Ra2 / Ra1 <1.00 can be achieved, peeling of plating and the like in the adjacent portion of the hollow structure can be suppressed. Although this reason is not explained, it can be considered as follows. That is, it is estimated that the photosensitive film laminate having a protective film has the following: The surface morphology having a certain thickness after peeling the protective film and exposing the surface of the photosensitive film gradually changes over time. If the proportion of the change is When it is constant, for the wall material, the degree of adhesion between the base material, the cover material, and the wall material becomes more appropriate, which can prevent the remaining developing solution used during development from penetrating into the peripheral portion of the hollow structure. As a result, it becomes It can suppress peeling caused by the remaining developer. However, this is only a speculative degree and is not necessarily applicable. In addition, in the present invention, the place where the protective film is peeled and left for 180 minutes in a state where the surface of the photosensitive film is exposed is the yellow light.

From the viewpoint of further suppressing the change in the shape of the surface of the photosensitive film over time from a moderate shape change, 0.50 ≦ Ra2 / Ra1 ≦ 0.95 is preferred, and 0.60 ≦ Ra2 / Ra1 ≦ 0.90 is more preferred.

The maximum height of the photosensitive film on the surface in contact with the protective film after the protective film was peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and left in an environment at 23 ° C and a relative humidity of 42% for 180 minutes. In the case of Ry2, if a photosensitive film laminate that satisfies 0.30 ≦ Ry2 / Ry1 <1.00 can be satisfied, peeling such as plating can be further suppressed. In addition, in the present invention, in a state where the protective film is peeled off and the surface of the photosensitive film is exposed, it is left under a yellow light as a place for 180 minutes.

From the viewpoint of further suppressing the change of the shape of the surface of the photosensitive film over time from a moderate shape change, 0.35 ≦ Ry2 / Ry1 ≦ 0.80 is more preferable, and 0.40 ≦ Ry2 / Ry1 ≦ 0.70 is more preferable.

Also, the arithmetic surface roughness Ra "or the maximum height Ry" of the surface in contact with the support film in the photosensitive film is also in the same range or the rate of change as the arithmetic surface roughness Ra or the maximum height Ry of the surface in contact with the protective film. good. In particular, it is an unprotected film, which is sequentially provided with a supporting film, and is effective when a photosensitive film laminate with a photosensitive film formed of a photosensitive composition is used. In this case, it is preferable that the supporting film and the protective film described later are made of the same material or thickness.

In the present invention, the "arithmetic average surface roughness Ra" and the "maximum height Ry" are expressed as values measured by a measuring device in accordance with JIS B0601-1994. The measurement method will be specifically described below. The arithmetic average surface roughness Ra and the maximum height Ry can be measured using a shape measurement laser microscope (for example, VK-X100 manufactured by Keyence Corporation). After starting the shape measurement laser microscope (same as VK-X100) body (control part) and VK observation application (VK-H1VX manufactured by Keyence Co., Ltd.), a sample (photosensitive film) to be measured was placed in the x-y stage. Rotate the lens of the microscope section (VK-X110 manufactured by Keyence Co., Ltd.), select an objective lens with a magnification of 10 times, and use the image observation mode of VK observation application (same as VK-H1VX) to roughly adjust the focus and brightness. Operate the x-y stage so that the part to be measured on the surface of the sample is adjusted to reach the center of the screen. Change the objective lens with 10x magnification to 50x magnification, and use the autofocus function of the image observation mode of VK observation application (same as VK-H1VX) to align the focal length on the surface of the sample. Select the simple mode of the shape measurement label of VK observation application (same as VK-H1VX), and press the measurement start button to measure the surface shape of the sample to obtain the surface image file. The VK analysis application (VK-H1XA manufactured by Keyence Co., Ltd.) was started, and the obtained surface image file was displayed, and then tilt correction was performed. The observation measurement range (horizontal) in the measurement of the surface shape of the sample was set to 270 μm. Performance line roughness window. In the parameter setting area, select JIS B0601-1994, select the horizontal line from the measurement line button, and display the horizontal line at any place in the surface image. Press the OK button to get the arithmetic average surface roughness. The value of Ra and the maximum height Ry. Further, horizontal lines are expressed at four different points in the surface image, and the values of the arithmetic average surface roughness Ra and the maximum height Ry are obtained. The average of the five values obtained by each calculation is used as the arithmetic average surface roughness Ra and the maximum height Ry of the sample surface. In addition, for the above-mentioned measurement of the arithmetic average surface roughness Ra and the maximum height Ry, a photosensitive film in a state before the hardening step such as exposure is used as a measurement sample user. As a laminate according to the present invention, when a protective film is laminated on a photosensitive film, a measurement sample in a state where the protective film is peeled off is used before laminating the substrate. At this time, after the protective film was peeled to expose the photosensitive film (1 minute) and 180 minutes later, the "arithmetic average surface roughness Ra" and "maximum height Ry" of the sample surface were measured. The measurement environment in the present invention is set to a temperature of 23 ° C and a relative humidity of 42%.

When the surface morphology of the photosensitive film is set within the range of the specific arithmetic average surface roughness Ra and the maximum height Ry, a conventionally known method can be applied. However, from the viewpoint of ease of forming the surface morphology, The protective film described later can be used to form a photosensitive film by adjusting the arithmetic average surface roughness Ra and the maximum height Ry. In addition, a protective film having a specific arithmetic average surface roughness Ra and a maximum height Ry is affixed, and then the protective film is peeled off. Then, another protective film having a different arithmetic average surface roughness Ra and a maximum height Ry is exposed to light. The thickness of the surface of the photosensitive film can be adjusted by attaching the surface of the flexible film.

In addition, the change in the surface morphology of the photosensitive film after the protective film is peeled off can be adjusted by the type or blending amount of the components contained in the photosensitive composition before curing of the photosensitive film. For example, it can be adjusted by adding materials having different solubility parameters (SP values), using an appropriate material having a glass transition temperature (Tg) or a weight average molecular weight, or using a filler as appropriate, but it is not limited thereto. In the present invention, the composition in the photosensitive composition forming the photosensitive film is not particularly limited, but may contain a photocurable compound, a photopolymerization initiator, a thermally crosslinked material, an inorganic filler, and the like. Hereinafter, each component which comprises a photosensitive composition is demonstrated.

[Photocurable compound]
The photosensitive composition used for the photosensitive film laminated body of this invention may contain the component which hardens | cures by irradiation of ionizing radiation, such as an ultraviolet-ray, and a photocurable compound is mentioned as an example. The photocurable compound is a compound having an ethylenically unsaturated double bond, and the compound may contain any of a resin, an oligomer, and a monomer. Examples of such photocurable compounds include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; 2-hydroxyethyl (methyl) ) Hydroxyalkyl (meth) acrylates such as acrylate, 2-hydroxypropyl (meth) acrylate; mono- or di-alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol (Meth) acrylic acid esters; hexanediol, trimethylolpropane, pentaerythritol, bistrimethylolpropane, dipentaerythritol, polyhydroxy alcohols such as parahydroxyethyl isocyanurate, or these ethylene oxides or rings Polyvalent (meth) acrylates of oxypropane adducts; ethoxylated ethylene oxides such as phenoxyethyl (meth) acrylate, polyethoxydi (meth) acrylate of bisphenol A (Meth) acrylates of alkane or propylene oxide adducts; of glycidyl ethers such as glycerol diglycidyl ether, trimethylolpropane triglycidyl ether, triglycidyl isocyanurate ( (Meth) acrylates; and melamine (meth) acrylates. In addition, in this specification, (meth) acrylate means the term of acrylate, methacrylate, and these mixtures, and it is the same also about other similar expressions.

In addition to the above, urethane monomers such as a (meth) acrylate compound having a amine bond, a methacrylate compound having a urethane bond, or a urethane may be mentioned. Ester oligomers, etc.

The photocurable compound may be a photosensitive resin containing a carboxyl group by reacting an epoxy resin, a phenol resin, or the like with an unsaturated carboxylic acid such as acrylic acid or methacrylic acid. Such a carboxyl group-containing photosensitive resin can be polymerized or cross-linked to harden by light irradiation, and further contains a carboxyl group, which is not only a solvent development but also an alkali development property. In particular, a developer having a weak alkalinity, specifically pH 7.0 or higher and 12.0 or lower, is also preferred from the viewpoint of excellent developability.

Specific examples of the carboxyl group-containing photosensitive resin include the following compounds (either an oligomer or a polymer may be used).
(1) A (meth) acrylic acid is reacted with a bifunctional or higher polyfunctional (solid) epoxy resin, and phthalic anhydride, tetrahydrophthalic anhydride, Carboxyl group-containing photosensitive resin to which a dibasic acid anhydride such as hydrogen phthalic anhydride is added,
(2) The hydroxyl group of a bifunctional (solid) epoxy resin is further epoxidized with epichlorohydrin to react (meth) acrylic acid in a polyfunctional epoxy resin, and a dibasic acid anhydride is made into the generated hydroxyl group. Carboxyl group-containing photosensitive resin,
(3) An epoxy compound having two or more epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, and unsaturated groups such as (meth) acrylic acid Carboxylic acid obtained by reacting a monocarboxylic acid, and reacting a polyhydric acid anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid with respect to the alcoholic hydroxyl group of the obtained reaction product. Photosensitive resin,
(4) For bisphenol A, bisphenol F, bisphenol S, novolac type phenol resin, poly-p-hydroxystyrene, naphthol and aldehyde condensation products, and dihydroxynaphthalene and aldehydes condensation products are equal to 1 In the reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups in the molecule with an alkylene oxide such as ethylene oxide or propylene oxide, an unsaturated monocarboxylic acid such as (meth) acrylic acid is used. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic acid anhydride with a reaction product obtained,
(5) A reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propyl carbonate, containing an unsaturated group Carboxyl group-containing photosensitive resin obtained by reacting a monocarboxylic acid and reacting a polybasic acid anhydride with the obtained reaction product,
(6) Diisocyanate compounds such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and polycarbonate-based polyols, polyether-based polyols, and polyester-based polyols Polyaddition reaction of diol compounds such as polyolefin polyols, acrylic polyols, bisphenol A-based alkylene oxide adduct diols, compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups, etc. A photosensitive urethane resin containing a terminal carboxyl group formed by reacting an acid anhydride at the terminal of an ester resin,
(7) A carboxyl group-containing urethane resin containing a diisocyanate and a polyaddition reaction of a carboxyl group-containing diol compound and a diol compound, such as dimethylolpropionic acid and dimethylolbutyric acid. In the synthesis, adding a hydroxyalkyl (meth) acrylate is equivalent to a compound having one hydroxyl group and one or more (meth) acrylfluorenyl groups in the molecule, and a terminal (meth) acrylated carboxyl group-containing photosensitive amino group Formate resin,
(8) For the synthesis of a carboxyl group-containing urethane resin by the polyaddition reaction of a diisocyanate, a diol compound containing a carboxyl group, and a diol compound, isophorone diisocyanate and pentaerythritol triacrylate are added. Moore reactants, etc., compounds having one isocyanate group and one or more (meth) acrylfluorene groups in the molecule, and a terminal (meth) acrylated photosensitive urethane resin containing a carboxyl group ,
(9) For a polyfunctional oxetane resin, dicarboxylic acids such as adipic acid, phthalic acid, and hexahydrophthalic acid are reacted, and the generated primary hydroxyl group is added to a dibasic acid anhydride. Carboxyl-containing polyester resin, which further makes glycidyl (meth) acrylate and α-methyl glycidyl (meth) acrylate equal to one epoxy group and one or more (methyl groups) in one molecule. ) A carboxyl group-containing photosensitive resin obtained by addition of an acrylic fluorenyl compound,
(10) The carboxyl group-containing photosensitive resin according to any one of the above (1) to (9), wherein a compound having a cyclic ether group and a (meth) acrylfluorenyl group is added in one molecule Photosensitive resin,
(11) By copolymerizing unsaturated carboxylic acids such as (meth) acrylic acid with unsaturated group-containing compounds such as styrene, α-methylstyrene, lower alkyl (meth) acrylates, and isobutylene, The obtained carboxyl group-containing resin makes the 3,4-epoxycyclohexyl methacrylate equal to a carboxyl group-containing photosensitive resin which reacts a compound having a cyclic ether group and a (meth) acryl group in one molecule. Cite. In addition, the term (meth) acrylate means the term of acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions below.

Although the weight-average molecular weight of the photocurable compound varies depending on the resin skeleton, it is generally preferred to be 2,000 to 200,000. When the weight average molecular weight is set to 2,000 or more, non-stick performance or resolution can be improved. Moreover, the change of state can be made appropriate by the aging of the surface of the coating film, and the adhesion to the substrate can be further improved. Moreover, when the weight average molecular weight is 200,000 or less, developability and storage stability can be improved. A preferred weight average molecular weight is 4,000 to 150,000, more preferably
5,000 to 100,000. The weight average molecular weight can be measured by a gel permeation chromatography (GPC) method (polystyrene standard).

When the blending amount of the photocurable compound is also included in the composition when a heat-crosslinking material to be described later is included, when the total amount of the photocurable compound and the heat-crosslinking material is 100 parts by mass in terms of solid content, 50 ～ 90 parts by mass are preferred. When the blending amount of the photocurable compound is within the above range, a hollow structure having higher strength can be formed. In addition, the change in state can be made appropriate by the aging of the surface of the coating film, and the adhesion to the substrate can be further improved.

[Heat crosslinked material]
By adding a heat-crosslinking material, the heat resistance of a photosensitive film can be improved. The heat-crosslinked material can be used alone or in combination of two or more. As the heat-crosslinkable material, any of known ones can be used. For example, amine resins such as melamine resin, benzoguanamine resin, melamine derivative, and benzoguanamine derivative, isocyanate compounds, block isocyanate compounds, cyclic carbonate compounds, epoxy compounds, and oxetane compounds can be used. Well-known thermosetting components such as episulfide resins, bismaleimide, carbodiimide resins, melamine resins, urea resins, polyimide resins, novolac resins, such as novolac, cresol novolac, and the like. Among these, from the viewpoint of the adhesion between the cured material of the photosensitive composition and the substrate, epoxy resin, melamine resin, and urea resin are preferable, and epoxy resin is more preferable.

The blending amount of the heat-crosslinkable material is the case where the photocurable compound is also contained in the composition. When the solid content is converted, the total amount of the photocurable compound and the heat-crosslinkable material is 100 parts by mass. ～ 40 parts by mass are preferred. When the blending amount of the thermally crosslinked material is set within the above range, a hollow structure having higher strength can be formed. Moreover, when the compounding quantity of a heat-crosslinking material is 40 mass parts or less, since the ratio of a photocurable compound increases, resolution can be improved further.

When an epoxy resin or the like is used as the heat-crosslinking material, a curing agent that can harden the epoxy resin may be further contained. Examples of the curing agent include amines, imidazoles, polyfunctional phenols, anhydrides, isocyanates, and polymers containing these functional groups, and a plurality of these may be used as necessary.

[Photopolymerization initiator]
Specific examples of the photopolymerization initiator include bis- (2,6-dichlorobenzyl) phenylphosphine oxide and bis- (2,6-dichlorobenzyl) -2,5- Dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzylidene) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzylidene) -1-naphthalene Phosphine oxide, bis- (2,6-dimethoxybenzyl) phenylphosphine oxide, bis- (2,6-dimethoxybenzyl) -2,4,4-trimethyl Amylphosphine oxide, bis- (2,6-dimethoxybenzyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6-trimethylbenzyl) ) -Diphenylphosphine oxides such as phenylphosphine oxide; 2,6-dimethoxybenzylidenediphenylphosphine oxide, 2,6-dichlorobenzylidenediphenylphosphine oxide, 2, 4,6-Trimethylbenzylidenephenylphosphonic acid methyl ester, 2-methylbenzylidenediphenylphosphine oxide, neopentylphenylphenylphosphonate isopropyl ester, 2,4, Monomethylphosphonium oxides such as 6-trimethylbenzylidene diphenylphosphine oxide; phenyl (2,4,6-trimethylbenzylidene) phosphonic acid ethyl, 1-hydroxy-cyclohexyl Phenyl ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy-1- {4- [4 -(2-hydroxy-2-methyl-propyl ) -Benzyl] phenyl} -2-methyl-propane-1-one, 2-hydroxy-2-methyl-1-phenylpropane-1-one, and other hydroxyacetophenones; benzoin, benzene Methyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether and other benzoin; benzoin alkyl ethers; benzophenone, p-methyl Benzophenones such as methyl benzophenone, mignonone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone ; Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1 -Hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-acetone, 2-benzyl-2-dimethylamine -1- (4-morpholinophenyl) -butanone-1, 2- (dimethylamino) -2-[(4-methylphenyl) methyl) -1- [4- ( 4-morpholinyl) phenyl] -1-butanone, acetophenones such as N, N-dimethylaminoacetophenone; thioxanthone, 2-ethylthioxanthone, 2-iso Propylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylsulfan Base Thioxanthone such as ketones; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-pentylanthraquinone, Anthraquinones such as 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal, benzyl dimethyl ketal; ethyl-4-dimethylamino benzoate, 2- (Dimethylamino) benzoates such as ethyl benzoate, ethyl p-dimethylbenzoate; 1,2-octanedione, 1- [4- (phenylthio) -, 2- (O-Benzamoxime)], ethyl ketone, 1- [9-ethyl-6- (2-methylbenzyl) -9H-carbazol-3-yl]-, 1 -(O-acetamoxime) and other oxime esters; bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) ) Phenyl) titanium, bis (cyclopentadienyl) -bis [2,6-difluoro-3- (2- (1-pyrrole-1-yl) ethyl) phenyl] titanium and other titaniumlocenes; Phenyl disulfide 2-nitrofluorene, Butyroin, fennel ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide, and the like.

The blending amount of the photopolymerization initiator is when the photocurable compound is contained in the composition. When 100 parts by mass of the photocurable compound is converted into solid content, it is preferably 0.1 to 10 parts by mass. When the blending amount of the photopolymerization initiator is within the above range, the resolution can be further improved.

The photopolymerization initiator may be used in combination, and a photoinitiator or a sensitizer may also be used. Examples of the photoinitiator or sensitizer include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. Wait. Although these compounds may be used as photopolymerization initiators, they are preferably used in combination with photopolymerization initiators. Moreover, a photoinitiator or a sensitizer may be used individually by 1 type, and may use 2 or more types together.

In addition, since these photopolymerization initiators, photostarters, and sensitizers absorb specific wavelengths, depending on circumstances, the sensitivity may be reduced or they may function as ultraviolet absorbers. However, it is not only used for the purpose of improving the sensitivity of these compositions. If necessary, it absorbs light of a specific wavelength to improve the surface light reactivity, and can improve the shape accuracy when exposed or developed.

[Filler]
By adding a filler to the photosensitive composition, it is possible to improve the hardness or heat resistance of the coating film, and it is also possible to adjust the change of the surface morphology of the photosensitive film over time. As such a filler, a known inorganic or organic filler can be used, but an inorganic filler is preferred. Examples of the inorganic filler include metal hydroxides such as barium sulfate, silicon dioxide, mica, hydrotalcite, talc, metal oxides, and aluminum hydroxide. Of these, silicon dioxide and mica are preferred. Examples of the silicon dioxide include spherical silicon dioxide and amorphous silicon dioxide.

To the photosensitive composition, if necessary, other resins other than the above, a thermal radical generator, a polymerization inhibitor, an adjuvant, an organic solvent, and the like may be added.

For example, heat resistance can be improved by adding other resins. Examples of other resins include polyimide, polyoxazole and precursors thereof, novolac resins such as phenol novolac and cresol novolac, polyamidamine, polyimide, phenoxy resin , Polyether, etc. These may be used individually by 1 type, and may use 2 or more types together.

The polyfluoreneimide resin may be made alkali-soluble. Specifically, it may have an alkali-soluble group such as a carboxyl group or an acid anhydride group in addition to the sulfonium imino group. For the introduction of the alkali-soluble group, a known method can be used. Examples thereof include resins obtained by reacting a carboxylic acid anhydride component with at least one of an amine component and an isocyanate component. The fluorene imidization can also be performed by thermal fluoridation, or by chemical fluoridation, or it can be produced by using these in combination.

In addition, by adding a thermal radical generator, the photocurable compound can be cured at a low temperature and in a short time. Examples of the thermal radical generator include peroxides and azo compounds.

Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, and phenothiazine. Examples of the bonding aid include silane coupling agents such as γ-glycidoxysilane, aminosilane, and γ-ureasilane.

The photosensitive film is formed by coating the photosensitive composition on one side of a supporting film and drying it. Considering the coating property of the photosensitive composition, the photosensitive composition is diluted with an organic solvent to adjust the viscosity to a suitable viscosity, and a notch wheel coater, a blade coater, a lip coater, a rod coater, and extrusion coating are used. Machine, reverse coater, transfer roll coater, gravure coater, spray coater, rod coater, roll coater, notch wheel coater, slit die coater, spin coater, etc. After coating, the organic solvent is volatilized by drying to obtain a non-stick coating film. There is no particular limitation on the coating film thickness, but generally the film thickness after drying is suitably selected from the range of 0.5 to 500 μm. From the viewpoint of use as a material for forming a wall portion or a cover portion of a hollow structure, a range of 1 to 300 μm is preferred.

The usable organic solvent is not particularly limited, and examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and petroleum solvents. . More specific examples include ketones such as methyl ethyl ketone (MEK) and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methylcellosolve, butylcellosolve, Glycol ethers such as carbitol, methylcarbitol, butylcarbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; Ethyl acetate, butyl acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether Esters such as acetate; Alcohols such as ethanol, propanol, ethylene glycol, propylene glycol; Aliphatic hydrocarbons such as octane, decane; Petroleum systems such as petroleum ether, naphtha, hydrogenated naphtha, solvent naphtha Solvents, other N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylmethylene, γ-butyrolactone, and the like. Such organic solvents can be used alone or as a mixture of two or more.

Organic solvent volatilization and drying can use hot air circulation type drying furnace, IR furnace, heating plate, convection oven, etc. (when using a heat source with air heating method by steam, the hot air in the dryer is blown by counter current contact method and nozzle Into the support). The volatile drying conditions can be appropriately selected from the range of a temperature of 60 to 120 ° C and a time of 1 to 60 minutes.

[Protective film]
The photosensitive film laminate system of the present invention is for the purpose of simultaneously preventing the adhesion of dust and the like on the surface of the photosensitive film and improving the handleability, and further aims to adjust the arithmetic average surface roughness Ra of the surface of the photosensitive film. The supporting film of the photosensitive film is a protective film provided on the opposite side.

As the protective film, for example, a polyester film, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, etc. can be used, but a polypropylene film is particularly preferred. In addition, it is preferable to select a material in which the adhesive force between the protective film and the photosensitive film is smaller than the adhesive force between the protective film and the photosensitive film. When the photosensitive film laminate is used, the protective film may be more easily peeled.

Although the thickness of the protective film is not particularly limited, it may be appropriately selected depending on the application within a range of about 10 to 200 μm.

In the present invention, it is preferable to use a protective film which allows the arithmetic mean surface roughness Ra 'of the surface of the protective film on the side of the surface in contact with the photosensitive film to be 0.10 m or more. Further, it is preferable to use a protective film which can make the arithmetic mean surface roughness Ry 'of the surface of the protective film on the side of the surface in contact with the photosensitive film be 1.00 m or more. By using a protective film having such a surface morphology, a photosensitive film having an arithmetic average surface roughness Ra of 0.10 μm or more can be easily formed, and a photosensitive film having an arithmetic average surface roughness Ry of 1.00 μm or more can be formed. Easier to form. The arithmetic mean surface roughness Ra 'of the protective film is preferably when it is 0.15 m or more, and more preferably when it is 0.20 m or more. When the upper limit is to be set, it is preferably 1.00 μm or less, more preferably 0.80 μm or less, and even more preferably 0.60 μm or less.

The maximum height Ry 'of the protective film on the surface side that is in contact with the photosensitive film is preferably 1.20 m or more, and more preferably 1.40 m or more. When the upper limit is to be set, it is preferably 5.00 μm or less, more preferably 4.00 μm or less, and even more preferably 3.00 μm or less. Among them, the meanings of the arithmetic average surface roughness Ra 'and the maximum height Ry' or the specific measurement method are as described in the above-mentioned [photosensitive film]. In addition, the arithmetic mean surface roughness Ra 'of the protective film and the arithmetic mean surface roughness Ra of the photosensitive film, the maximum height Ry' of the protective film, and the maximum height Ry of the photosensitive film are not necessarily the same, but by suitably The adjustment can set the arithmetic average surface roughness Ra and the maximum height Ry of the photosensitive film within the specific ranges as described above.

The method of adjusting the protective film having the arithmetic average surface roughness Ra 'and the maximum height Ry' as described above is not particularly limited. For example, when a filler is added to the resin of the protective film, the particle diameter of the filler or the The amount is added, but the surface of the protective film may be spray-treated, or the surface may be set to a predetermined shape by hairline processing, matte coating, or chemical etching.

[Hardened matter]
A cured product is formed using the photosensitive film laminate of the present invention. As an example of this hardened | cured material, the method of forming the hollow structure body which has a wall part and a cover part using the photosensitive film laminated body of this invention is demonstrated.

[Method of forming wall part]
First, a wall portion is formed using a photosensitive film laminate. Specifically, it is through a lamination step of peeling a protective film from a photosensitive film laminate, laminating a photosensitive film on a substrate such as a substrate, and irradiating light through a photomask through a predetermined portion of the photosensitive film. An exposure step of photo-curing the exposed portion, a development step of removing the photo-cured portion of the photosensitive film using a developing solution, and a photo-cured portion of the photosensitive film by light or heat This hardening step is a hardening step to obtain a desired wall portion. Each step is described below.

In the laminating step, the protective film is peeled from the photosensitive film laminate to expose the photosensitive film surface side, and the substrate is laminated. The lamination can be performed by hot pressing or the like. Examples of the substrate to be adhered include a silicon wafer, a glass substrate, a ceramic substrate, an aluminum substrate, a stainless steel substrate, a glass epoxy substrate, a polyester substrate, and a polyimide substrate. Examples of the method of hot pressing include hot pressing, roll lamination, vacuum roll lamination, vacuum pressure treatment, and film vacuum lamination. The hot pressing temperature is from the viewpoint of adhesion to the substrate and the embedding property, and from the viewpoint that the photosensitive composition can be maintained at a good resolution without being cured during the hot pressing. It is preferably 35 to 100 ° C, more preferably 40 to 85 ° C. The lamination pressure is preferably 0.005 to 10 MPa, and more preferably 0.005 to 3 MPa.

Next, an exposure step is performed. As the exposure, although there are negative and positive types, negative types are preferred. In the case of a negative type, light is irradiated to the photosensitive thin film laminated body laminated on the substrate through a negative mask having a desired pattern that can be formed into a wall shape, and the exposed portion of the photosensitive film is lighted. hardening. Among them, examples of the active light used for exposure include ultraviolet rays, visible rays, electron beams, and X-rays. Among these, ultraviolet rays and visible rays are particularly preferred. In addition, it is preferable to use a mask exposed through an i-line (365 nm), an h-line (405 nm), and a g-line (436 nm) of an ultra-high pressure mercury lamp through a photomask. A method of directly drawing a photosensitive film using a laser having a wavelength of 405 nm in a maskless manner can also be mentioned. In this step, the support film constituting the photosensitive film laminate may be peeled before exposure, or may be peeled after exposure. In addition, the support film may be peeled before exposure, or a heat treatment may be performed at a temperature of 40 ° C. to 150 ° C. for 5 seconds to 60 minutes using an oven or a heating plate without peeling. In addition, the support film may be peeled after exposure, or a heat treatment may be performed at a temperature of 40 to 150 ° C. for 5 seconds to 60 minutes using an oven or a heating plate without peeling.

Next, the portions of the photosensitive film other than the light-cured portion (unexposed portions) are removed using an organic solvent-based or alkaline aqueous solution-based developing solution to form a pattern of the wall portion.

As the developing solution, N-methylpyrrolidone, ethanol, cyclohexanone, cyclopentanone, propylene glycol methyl ether acetate, γ-butyrolactone, triethylene glycol dimethyl ether, methyl Organic solvents such as amyl ketone (2-heptanone) and butyl acetate. In addition, alkaline aqueous solutions such as sodium carbonate, sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, and tetramethylammonium hydroxide (TMAH) can be used. . Among these, from the viewpoint of the development speed, it is preferable to use propylene glycol methyl ether acetate in the case of solvent development. On the other hand, in the case of alkali development, sodium carbonate, sodium hydroxide, and tetramethylammonium hydroxide (TMAH) are preferred.

Examples of the development method include spraying a developing solution on a photosensitive film and immersing the developing solution in the developing solution, or applying ultrasonic waves without immersion.

After development, if necessary, it may be performed with water or alcohols such as methanol, ethanol, isopropanol, or n-butyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether acetate, and the like. Wash lightly (rinse) is better. Examples of the light washing method include spraying a developing solution on the surface of a photosensitive film and immersing the developing solution in the developing solution, or applying ultrasound without immersion.

Next, a light-cured portion (exposed portion) of the photosensitive film is cured by light or heat to form a wall portion. In the case where the curing (curing) after development is performed by heat, it is preferable to select a temperature and perform the stepwise heating while performing the heating for 1 to 2 hours. The temperature for heat curing is suitably selected from 120 to 400 ° C, and the time is suitably selected from the range of 60 to 120 minutes. The temperature is also fixed at a certain temperature for stepwise heating. When hardening, it is preferable to heat-treat in inert gas, such as nitrogen and argon. The final heating temperature is preferably 150-350 ° C. Moreover, you may perform photohardening before or after thermal hardening, or you may perform photohardening instead of thermal hardening.

The thickness of the photosensitive film to be formed on the wall is preferably 1 to 3,000 μm, more preferably 5 to 1,000 μm, more preferably 10 to 500 μm, particularly preferably 20 to 200 μm, and most preferably 20 to 100 μm. good. When the thickness of the photosensitive film is 1 μm or more, the shape of the wall portion can be easily maintained, and large deformation is not easily caused even under high temperature and high pressure conditions during molding. When the thickness is 3,000 μm or less, the light transmittance of the photosensitive film during exposure is not easily hindered. In addition, the thickness of the wall portion is increased by repeating the laminating step of overlapping the photosensitive films. The final film thickness of the wall portion formed through the hardening step is also preferably 1 to 3,000 μm, more preferably 5 to 500 μm, and even more preferably 10 to 200 μm.

[Formation of the cover]
The wall portion formed by the cured product of the photosensitive thin film formed by the above-mentioned forming method has a sufficient film thickness, and may be covered by covering the upper end of the wall portion with a ceramic substrate, a Si substrate, a glass substrate, or a metal substrate. The cover is formed into a hollow structure, but a cover portion may be formed using a photosensitive film laminate. A method for forming a cover portion using a photosensitive film laminate is described below.

At the upper end of the wall portion formed as described above, the photosensitive film laminate of the peeling protective film is laminated and exposed, and development is performed if necessary, and the light-cured photosensitive film is cured to form a cover portion. Make a hollow structure. When the cover portion is formed using the photosensitive film laminate, although the development step is not necessary, for example, when a plurality of hollow structure devices are manufactured at the same time, only the size corresponding to the cover portion of the hollow device is performed through a photomask. After exposure, the surrounding unexposed portions can be developed to separate the pieces.

The lamination, exposure, development, and curing of the photosensitive film laminate can be performed in the same manner as in the formation of the wall portion. Among them, the bonding at the time of forming the laminated body of the wall portion and the lid portion can be performed by hot pressing. Examples of the hot-pressing method include a hot-pressing process, a roll lamination process, a vacuum roll lamination process, a vacuum pressure treatment process, and a film vacuum-type vacuum lamination process. Among them, a roll lamination process is also preferred. The hot-pressing temperature is preferably 20 ° C or higher from the viewpoint of adhesion to the adherend and embedding property. In addition, from the viewpoint of preventing deterioration of the resolution of the pattern formation during exposure and development during the heat pressing of the photosensitive resin component, the heat pressing temperature is preferably 150 ° C. or lower. That is, from the viewpoint of adhesion and embedding to the substrate, and from the viewpoint that the curing of the photosensitive composition cannot be performed during the thermocompression and a good resolution can be maintained, the thermal compression temperature is 20 to A temperature of 150 ° C is preferred, a temperature of 35 to 100 ° C is more preferred, and a temperature of 40 to 85 ° C is more preferred. The lamination pressure is preferably 0.005 to 10 MPa, and more preferably 0.005 to 3 MPa.

Although the supporting film constituting the photosensitive film laminate can be peeled off before exposure, peeled off after exposure, or peeled off after curing of the photosensitive film, the cured product of the photosensitive film which will become the cover portion is formed only by From the viewpoint of stability, the state where the wall portion is supported is preferably peeling after exposure or peeling after curing. In addition, the support film may be peeled before exposure, or a heat treatment may be performed at a temperature of 40 to 150 ° C. for 5 seconds to 60 minutes using an oven or a heating plate without peeling. After the exposure, the support film may be peeled off, or a heat treatment may be performed at a temperature of 40 to 150 ° C. for 5 seconds to 60 minutes using an oven or a heating plate without peeling. For further development or hardening, the wall portion and the lid portion may be performed simultaneously. The tensile elastic modulus of the cured film forming the cover is preferably 2.0 GPa or more.

The thickness of the photosensitive film to be covered is preferably 1 to 3,000 μm, more preferably 5 to 1,000 μm, more preferably 10 to 500 μm, particularly preferably 20 to 200 μm, and most preferably 20 to 100 μm. good. The final film thickness of the cover portion formed through the curing step is preferably 10 μm to 3,000 μm. When the thickness of the cover portion is 10 μm or more, it is easy to maintain the shape of the hollow structure, and it is unlikely to cause excessive deformation even under high temperature and high pressure conditions during molding. When the thickness is 3,000 μm or less, the light transmittance of the photosensitive film during exposure is not easily hindered. In addition, the thickness of the cover portion can be increased by repeating the laminating step of overlapping the photosensitive films.

In addition, in the present invention, the wall portion is formed without using the photosensitive film laminate of the present invention. Although the cover portion may be formed only by using the photosensitive film laminate of the present invention, the pattern of the wall portion and the When both sides use the photosensitive film laminate of the present invention, adhesion between the two can be made better, and peeling of plating or the like in the adjacent portion of the hollow structure can be suppressed at the same time.

According to the present invention, an electronic component having a hollow structure such as a SAW filter is formed by using a photosensitive film laminate of the present invention in a wall portion or a cover portion, and it is possible to suppress peeling of plating or the like in an adjacent portion of the hollow structure. . In addition, the inside of the hollow structure is moisture-proof by the wall portion and the cover portion, and the hollow structure can be maintained even at high temperatures. Therefore, hollow structures such as SAW filters, CMOS, CCD sensors, and MEMS are suitable as necessary electronic components. The miniaturization, low profile, and high functionality of electronic parts are useful. The photosensitive film laminate of the present invention is particularly suitable for use as a wall portion or a cover portion of a hollow structure of a SAW filter, and is a highly reliable electronic component in which peeling or the like is suppressed from being obtained in the adjacent portion of the hollow structure. Is particularly suitable from a viewpoint. The present invention can also be used as a printed circuit board such as a soldering resist, a plating resist, an etching resist, and an interlayer insulating material.

＜ SAW filter and its manufacturing method ＞
A method of forming a hollow structure having a wall portion and a cover portion using the photosensitive film laminate of the present invention will be described. As an example of an electronic part having a hollow structure, a surface acoustic wave (SAW) filter and a manufacturing method thereof The method is described below.

First, a protective film is peeled off from the photosensitive film laminate of the present invention on a substrate on which a 栉 -type electrode is formed to laminate a photosensitive film surface. For the lamination of the photosensitive film laminate, the same method as that described in the method for forming the wall portion can be used.

Next, after laminating the photosensitive film laminate, if necessary, a predetermined portion of the photosensitive film is irradiated with light through a negative mask having a desired pattern, and the exposed portion is light-cured. For the exposure, the same method as described in the method for forming the wall portion can be used.

Continue to remove portions other than the exposed portion of the photosensitive film, that is, the unexposed portion, with a developing solution to form a desired pattern. Then, the exposed portion of the photosensitive film is hardened by light or heat to form a cured material. The resulting wall. The steps of exposure, development, and hardening can be performed in the same manner as the method for forming the wall portion described above.

In addition, as described later, when the photosensitive film laminate of the present invention is used for forming a cover portion of a hollow structure of a SAW filter, the wall portion can be formed by a method other than the method of using the photosensitive film laminate of the present invention.

A hollow structure provided with a cover portion is formed on the upper end of the wall portion formed as described above. The cover portion is formed by the following steps: The protective film is peeled from the photosensitive film laminate of the present invention, the photosensitive film surface is bonded to the upper end of the wall portion, and then exposed, developed, and cured to form a cover. unit. The lid portion and the wall portion can be adhered, for example, by thermal pressure bonding using a roll laminate.

In addition, the lid portion may be a material other than the photosensitive film laminate of the present invention, and may be a substrate made of a known permanent resist or a sealing substrate such as ceramics. However, it is preferable that the cover is made of a material having excellent moisture and heat resistance and low water absorption. In this case, at least the wall portion formed using the photosensitive film laminate of the present invention can be used as a wall portion for forming a hollow structure of a SAW filter.

After the formation of the wall portion and the cover portion as described above, the electrodes are electrically connected to the wired conductors on the inside of the electrode and the substrate and on the opposite surface of the electrode, so the formation of plating and the mounting of metal balls can also be performed. Wait.

For the formation of the wall portion, a hole for forming an internal conductor inside the wall portion can be formed by exposure and development. Thereafter, a photosensitive film laminated on the supporting film is laminated on the wall portion, and exposed through a photomask. The photomask is used to shield only the part corresponding to the aperture of the internal conductor to be formed so that light cannot be transmitted, and the other parts are hardened by light to form a cover portion. The unexposed portion of the cover portion is intended to completely penetrate the hole formed in the interior of the wall portion previously formed, and after development, drawing is performed by performing a desmearing treatment or the like. Lasers can also be used for drawing the cover. As the laser, a known one such as a YAG laser, a carbon dioxide gas laser, and an excimer laser can be used. The exposure or laser irradiation can be appropriately selected and used according to the thickness of the wall portion, the shape of the internal conductor formed inside the wall portion, and the shape of the wiring pattern on the surface of the cover portion.

In addition, an internal conductor is formed in a hole formed inside the wall portion and the cover portion by a plating method or the like, and wiring is formed on the surface of the cover portion. In the present invention, the holes formed inside the wall portion and the lid portion can be formed with an inner conductor not only by a plating method but also by a conductor filling method using a resin paste containing a metal paste or a metal powder. Through these steps, the conductors through which the 栉 -type electrodes on the substrate are wired are electrically connected to the wiring conductors formed on the surface of the cover portion. Finally, the SAW filter of an electronic component having a hollow structure can be obtained by mounting a metal ball on the surface of a lid portion or the like by reflow.

The SAW filter can be sealed with a sealing material. In the case of sealing with a sealing material, the following steps are generally used, but the invention is not limited to these. First, a SAW filter is placed on a forming mold. Next, a solid sealing material sheet is set in the tank of the molding machine. Then, the sealing material is melted under the conditions of a mold temperature of 150 to 180 ° C, and pressure is applied to flow into the mold (molding). Finally, the sealing material is thermally hardened by pressing for 30 to 120 seconds, and then the mold is opened. After the molded product is taken out, the SAW filter is sealed.

Usually, the sealing by a sealing material is performed before the metal balls are mounted, and after the sealing, the sealed surface of the substrate is mounted on the opposite side by reflowing the metal balls. However, after the metal ball is mounted, sealing with a sealing material can also be performed. Not only one SAW filter sealed with a sealing material but also a plurality of SAW filters can be manufactured. At this time, the plurality of SAW filters formed on one substrate can be sealed with a sealing material and then cut to obtain each piece. Specifically, first, a plurality of SAW filters are manufactured on one substrate, and a wall portion and a cover portion are formed using the photosensitive film laminate of the present invention or the like. After that, it is sealed once with a sealing material, and the SAW filter can be obtained by dividing into individual pieces by a method such as cutting.

As described above, in the manufacturing steps of the SAW filter, the hollow film structure having a wall portion and a cover portion can be formed using the photosensitive film laminate of the present invention. As described above, the photosensitive thin film laminate of the present invention is a SAW filter in which peeling and the like of adjacent portions of a hollow structure are suppressed because the surface morphology changes within a specific range as described above. In addition, in the hollow structure, the wall portion and the cover portion formed by using the photosensitive film laminate of the present invention can be isolated from the surroundings and moisture-proof, so that corrosion of the aluminum electrode can be suppressed. In addition, since the cured product of the photosensitive film has a high elastic modulus at high temperatures, it has the advantage of maintaining a hollow structure even under the temperature and pressure of the sealing resin during molding.

Examples

Examples are given next to further describe the present invention, but the present invention is not limited to these examples. In addition, the "parts" and "%" below are all based on the quality unless otherwise specified. In addition, the operation in the following examples was performed at room temperature (23 ° C), a relative humidity of 42%, and a yellow light.

<Synthesis example 1>
＜ Synthesis of carboxyl group-containing resin ＞
A 2L flask equipped with a stirring device and a reflux tube was charged with a bifunctional bisphenol-A epoxy resin (re-310S, manufactured by Nippon Kayaku Co., Ltd.) as an epoxy compound having two or more epoxy groups in the molecule. , Epoxy equivalent: 183.5 g / equivalent) 367.0 parts, 144.1 parts of acrylic acid (molecular weight: 72.06) as a monocarboxylic acid compound having an ethylenically unsaturated group, and 1.02 parts of hydroquinone monomethyl ether as a thermal polymerization inhibitor, With 1.53 parts of triphenylphosphine as a reaction catalyst, the reaction was performed at a temperature of 98 ° C. until the acid value of the reaction solution became 0.5 mgKOH / g or less to obtain an epoxy carboxylic acid ester compound (theoretical molecular weight: 511.1).
Next, 445.93 parts of carbitol acetate as a reaction solvent, 0.70 parts of 2-methylhydroquinone as a thermal polymerization inhibitor, and dimethylol as a diol compound having a carboxyl group were added to the reaction solution. 118.8 parts of propionic acid (molecular weight: 134.1) was heated to 60 ° C. In this solution, 209.6 parts of isophorone diisocyanate (molecular weight: 222.29), which is a diisocyanate compound, was slowly added dropwise at a reaction temperature not exceeding 65 ° C. After the dropping was completed, the temperature was raised to 80 ° C., and the reaction was performed for 6 hours by infrared absorption spectrometry until the absorption near 2250 cm ⁻¹ disappeared. To this solution were added 36.7 parts of succinic anhydride (molecular weight: 100.1) and 43.0 parts of carbitol acetate as polybasic acid anhydrides. After the addition, the temperature was raised to 95 ° C., and the reaction was performed for 6 hours to obtain 65% by weight of a carboxyl group-containing photosensitive resin paint 1 having a weight average molecular weight of 10,000 and containing a carboxyl group-containing polyester urethane resin. The measured acid value was 66.61 mgKOH / g (solid content acid value: 102.5 mgKOH / g). The weight-average molecular weight is measured according to a conventional method by a gel permeation chromatography (GPC) method (polystyrene standard).

<Synthesis example 2>
＜ Synthesis of carboxyl group-containing resin ＞
A high-pressure high-temperature autoclave equipped with a thermometer, a nitrogen introduction device, an alkylene oxide introduction device, and a stirring device was charged with a novolac-type cresol resin (ShonorCRG951 manufactured by Aika Industrial Co., Ltd., OH equivalent: 119.4), 119.4 g, and hydroxide 1.19 g of potassium and 119.4 g of toluene were replaced with nitrogen in the system while stirring, and the temperature was raised by heating. Next, 63.8 g of propylene oxide was dripped in slowly, and reaction was performed at 125-132 degreeC and 0-4.8 kg / cm <^2> for 16 hours. After cooling to room temperature, 1.56 g of 89% phosphoric acid was added to the reaction solution and neutralized with potassium hydroxide to obtain a novolac cresol having a nonvolatile content of 62.1% and a hydroxyl value of 182.2 g / eq. Resin propylene oxide reaction solution. The obtained novolak-type cresol resin had an average alkylene oxide addition of 1.08 moles per 1 phenolic hydroxyl group.
293.0 g of an alkylene oxide reaction solution of the obtained novolac-type cresol resin, 43.2 g of acrylic acid, 11.53 g of methanesulfonic acid, 0.18 g of methylhydroquinone, and 252.9 g of toluene were charged into a container equipped with a stirrer, a thermometer, and an air blowing tube. In the reactor, air was blown in at a rate of 10 ml / minute, and the reaction was carried out at 110 ° C. for 12 hours while stirring. As the water produced by the reaction and toluene became an azeotropic mixture, 12.6 g of water was distilled off. Thereafter, it was cooled to room temperature, and the obtained reaction solution was neutralized with 35.35 g of a 15% sodium hydroxide aqueous solution, and then washed with water. Thereafter, toluene was replaced with 118.1 g of diethylene glycol monoethyl ether acetate with an evaporator, and distilled off to obtain a novolac type acrylate resin solution. Next, 332.5 g of the obtained novolak-type acrylate resin solution and 1.22 g of triphenylphosphine were charged into a reactor equipped with a stirrer, a thermometer, and an air blowing tube, and air was blown in at a rate of 10 ml / min. While stirring, 62.3 g of tetrahydrophthalic anhydride was slowly added, and the reaction was performed at 95 to 101 ° C. for 6 hours to obtain a carboxyl-containing photosensitive resin paint having an acid value of 88 mgKOH / g as a non-volatile content of 71%. 2.

<Synthesis example 3>
＜ Synthesis of carboxyl group-containing resin ＞
220 parts (1 equivalent) of cresol novolac epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S, epoxy equivalent 220g / eq), 140.1 parts of carbitol acetate, and 60.3 parts of solvent naphtha The mixture was placed in a flask, heated and stirred at 90 ° C, and dissolved.
Once the obtained solution was cooled to 60 ° C, 72 parts (1 mole) of acrylic acid, 0.5 parts of methylhydroquinone, and 2 parts of triphenylphosphine were added, and the solution was heated at 100 ° C for about 12 hours to obtain an acid value. The reaction was 0.2 mgKOH / g. Here, 80.6 parts (0.53 moles) of tetrahydrophthalic anhydride was added, and the mixture was heated at 90 ° C for about 6 hours to obtain a solid component having an acid value of 85 mgKOH / g and a solid content of 64.9% containing a carboxyl group. Resin paint 3.

<Synthesis example 4>
＜ Synthesis of carboxyl group-containing resin ＞
190 parts of EPPN-201 (manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent = 190) of a phenol novolak epoxy resin was placed in a four-necked flask equipped with a stirrer and a reflux cooler. 184 parts of carbitol acetate was added and dissolved by heating. Next, 0.46 parts of methylhydroquinone as a polymerization inhibitor and 1.38 parts of triphenylphosphine as a reaction catalyst were added. This mixture was heated at 95-105 degreeC, 72 parts (1 equivalent) of acrylic acid was dripped in slowly, and reaction was performed for 16 hours. The obtained reaction product (hydroxyl: 1 equivalent) was cooled to 80 to 90 ° C, and 50 parts (0.5 equivalent) of succinic anhydride was added to carry out a reaction for 8 hours. After cooling, the reaction product was taken out. In this way, a carboxyl group-containing photosensitive resin varnish 4 having a nonvolatile content of 65%, a solid matter acid value of 89 mgKOH / g, and a solid content of 65.0% was obtained.

<Preparation of photosensitive composition>
The contents and proportions (parts by mass) shown in Table 1 below were blended, and each component was kneaded to a uniform state to prepare photosensitive compositions 1 to 5. In addition, * 1 to * 22 in Table 1 indicate the following components.
* 1 Methylated melamine resin, manufactured by Sanwa Chemical Co., Ltd.
* 2 Epoxy skeleton-containing epoxy resin, manufactured by Osaka Gas Chemical Co., Ltd.
* 3 Bisphenol A epoxy resin (manufactured by DIC Corporation)
* 4 Biphenylaralkyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.)
* 5 Phenolic novolac epoxy resin (manufactured by DIC Corporation)
* 6 Dicyclopentadiene type epoxy resin (manufactured by DIC Corporation)
* 7 Synthesis Example 1 (combination amount is solid content)
* 8 Synthesis Example 2 (mixing amount is solid content)
* 9 Synthesis Example 3 (combination amount is solid content)
* 10 Synthesis Example 4 (mixing amount is solid content)
* 11 Alkali-available photosensitive resin with amidamine and imine structure (20% solids, manufactured by Nakago Paper Industry Co., Ltd.)
* 12 Acrylate of dipentaerythritol, manufactured by Kyoeisha Chemical Co., Ltd.
* 13 Acrylic ester of ε-caprolactone-modified dipentaerythritol, manufactured by Kyoeisha Chemical Co., Ltd.
* 14 Tricyclodecane dimethanol diacrylate, manufactured by Shin Nakamura Chemical Industry Co., Ltd.
* 15 Oxime ester-based photopolymerization initiator (ethyl ketone, 1- [9-ethyl-6- (2-methylbenzylidene) -9H-carbazol-3-yl]-, 1- (0 -Ethyl oxime)), manufactured by BASF Japan Co., Ltd.
* 16 Diphenyl (2,4,6-trimethylbenzyl) phosphine oxide (manufactured by IGM Resins)
* 17 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemical Industry Co., Ltd.)
* 18 Spherical silica, manufactured by Admatechs Co., Ltd.
* 19 Spherical silica particles with an average particle size of 100 nm
* 20 CIPigment Blue 15: 3
* 21 CIPigment Yellow 147
* 22 Paliogen Red K3580 (manufactured by BASF Japan)

＜ Production of protective film ＞
Production example 1
Weight average molecular weight (Mw) 3.0 × 10 ⁵ , molecular weight distribution
(Mw / Mn) 5.0, polypropylene resin particles with an isotactic component fraction of 95.0% were supplied to an extruder, melted at a resin temperature of 250 ° C, extruded through a T-die, and A metal drum having a surface temperature of 150 ° C. was rolled to form a film, and a cast roll sheet having a thickness of about 225 μm was produced. The unstretched casting roll sheet was also extended 5 times in the direction of flow at a temperature of 120 ° C, immediately after cooling to room temperature, and then tentered, and was extended 10 times in a horizontal direction at a temperature of 160 ° C to obtain Biaxially stretched polypropylene film 1 with a thickness of 12 μm. This biaxially stretched polypropylene film 1 was used as a protective film 1.

Production example 2
Weight average molecular weight (Mw) 3.1 × 10 ⁵ , molecular weight distribution
(Mw / Mn) 5.5, polypropylene resin particles with isotactic component fraction of 93.0% are supplied to the extruder, melted at a resin temperature of 250 ° C, extruded through a T-die, and the surface temperature is The film was formed by rolling on a metal drum kept at 150 ° C., and a cast roll sheet having a thickness of about 225 μm was produced. Continue to extend the unstretched cast roll sheet at a temperature of 200 ° C in the direction of flow 5 times, immediately after cooling to room temperature, and then stretch ten times in a transverse direction at a temperature of 160 ° C to obtain a thickness 15 μm biaxially stretched polypropylene film 2. This biaxially stretched polypropylene film 2 was used as a protective film 2.

Production example 3
Polypropylene resin pellets having a weight average molecular weight (Mw) of 3.0 × 10 ⁵ , a molecular weight distribution (Mw / Mn) of 5.0, and an isotactic component fraction of 95.0% were supplied to an extruder and melted at a resin temperature of 250 ° C. , And extruded through a T-die, coiled on a metal drum with a surface temperature maintained at 100 ° C. to form a film, and produced a cast roll sheet having a thickness of about 225 μm. Continue to stretch the unstretched cast reel sheet at a temperature of 120 ° C in the direction of flow 5 times, immediately after cooling to room temperature, and then stretch 10 times in a transverse direction at a temperature of 160 ° C with a tenter draw to obtain A biaxially stretched polypropylene film 3 having a thickness of 12 μm. This biaxially stretched polypropylene film 3 was used as the protective film 3.

＜ Production of Supporting Films ＞
After polyethylene terephthalate and a polyethylene terephthalate masterbatch containing 1.0% by mass of silicon dioxide having an average primary particle diameter of 1 μm were dried at 170 ° C., each was supplied at 2 ° C. The shaft extruder was melted at 290 ° C, and co-extruded by a T-die to form a film to produce an unstretched film. This unstretched film was further biaxially stretched to obtain a support film 1 having a thickness of 40 μm.

＜ Production of photosensitive film laminate ＞
Example 1
The arithmetic mean surface roughness Ra ′ and the maximum height Ry ′ of the protective film 1 obtained as described above were measured as follows. Ra ′ was 0.18 μm, and the maximum height Ry ′ was 1.28 μm.

For the measurement of the arithmetic average surface roughness Ra 'and Ry', a shape measurement laser microscope (VK-X100 manufactured by Keyence Corporation) was used. After starting the shape measurement laser microscope (same as VK-X100) body (control part) and VK observation application (VK-H1VX manufactured by Keyence Co., Ltd.), mount the measured protective film (will be related to photosensitivity) in the xy stage. The surface where the film contacts is the upper part). Rotate and rotate the lens of the microscope section (VK-X110 manufactured by Keyence Co., Ltd.), select the objective lens with a magnification of 10 times, and use the image observation mode of VK observation application (same as VK-H1VX) to roughly adjust the focus and brightness. . During the x-y stage, adjust the part of the sample surface to be measured so that it can reach the center of the screen. The objective lens with a magnification of 10 times is replaced by a magnification of 50 times. With the autofocus function of the image observation mode of the VK observation application (same as VK-H1VX), the focal length is aligned on the surface of the sample. Select the simple mode of the shape measurement label of VK observation application (same as VK-H1VX), and press the measurement start button to measure the surface shape of the sample to obtain the surface image file. Start the VK analysis application (VK-H1XA manufactured by Keyence Co., Ltd.), display the obtained surface image file, and perform tilt correction.

[Example 5]
The observation measurement range (horizontal) in the measurement of the surface shape of the sample was 270 μm. Display the line roughness window. In the parameter setting area, after selecting JIS B0601-1994, select the horizontal line from the measurement line button to display the horizontal line at any position in the surface image. Press the OK button to get the arithmetic average surface roughness. Ra 'and the maximum height Ry'. Further, horizontal lines are displayed at four different locations in the surface image, and the values of the arithmetic average surface roughness Ra 'and the maximum height Ry' are obtained. The average of the five values obtained by each calculation was used as the arithmetic average surface roughness Ra 'value and the maximum height Ry' value of the sample surface. The measurement was performed in an environment of room temperature (23 ° C) and a relative humidity of 42% RH.

Then, for 700 parts of the photosensitive composition 1 obtained as described above, methyl ethyl ketone was added at a ratio of 300 parts and diluted, and the mixture was stirred for 15 minutes with a mixer to obtain a coating solution. This coating liquid was uniformly applied on a support film 1 using a slit die, and dried at a temperature of 80 ° C. for 15 minutes to produce a dried photosensitive film 1 having a thickness of 25 μm. Next, the protective film 1 is attached to the photosensitive film 1 so that the measurement surface of the arithmetic average surface roughness Ra 'and the maximum height Ry' of the protective film 1 can be brought into contact with the surface of the photosensitive film 1 and bonded to the surface. The roller laminate was used to produce a photosensitive film laminate 1 (thickness of the photosensitive film of 25 μm) composed of three layers of a supporting film, a photosensitive film, and a protective film. In addition, as conditions for lamination by the roll laminate, it is suitably adjusted to a range of a roll temperature of 40 to 60 ° C. and a roll pressure of 0.2 to 0.4 MPa.

＜ Production of test substrate ＞
A test substrate was produced using the photosensitive film laminate 1 obtained as described above. The procedure for producing a test substrate will be described with reference to the drawings.
First, from the photosensitive film laminate 1, the protective film is peeled from the other two layers (supporting film / photosensitive film) at an angle of 90 ° and at a speed of 2.5 seconds / cm to expose the photosensitive film. The exposed surface of the photosensitive film is bonded to the surface of the prepared silicon wafer, and the laminated layer is heated and laminated using a roller to adhere the silicon wafer and the photosensitive film. In addition, as conditions for lamination by the roll laminate, the roll temperature was 60 ° C. and the roll pressure was 0.25 MPa.

Next, each of the examples and comparative examples was exposed to the support film of the photosensitive film via the following (i) and (ii) via a metal halide lamp with a pattern opening and exposure as described in Table 2 The combination of the amounts, after exposing the photosensitive film, the support film is peeled and the photosensitive film is exposed.
(i) a negative mask with an opening pattern with a grid size of 150 μm square and 50 μm square (refer to Figure 1), or
(ii) A negative mask (not shown) having an opening pattern with a grid size of 150 μm square and 100 μm square.

Thereafter, the exposed surface of the exposed photosensitive film was immersed in Examples 1 to 3 and Comparative Examples 1 and 2 at 23 ° C. for 1 minute in propylene glycol monomethyl ether acetate (PMA). For Example 4, a 1 wt% Na ₂ CO ₃ aqueous solution was developed at 30 ° C. and 2 MPa for 60 seconds. For Example 5, a 1 wt% Na ₂ CO ₃ aqueous solution was developed at 30 ° C. and 2 MPa for 300 seconds. Each test substrate after development was sufficiently washed with water until no developing solution remained. The pH of the 1 wt% Na ₂ CO ₃ aqueous solution was confirmed to be 11.6.

Then, each test substrate was heated at 120 ° C. for 30 minutes, and then the photosensitive film was cured, and around the 150 μm square openings in a grid shape, the following (i) or (ii) was obtained.
(i) a hardened film pattern of a wall portion having a width of 150 μm corresponding to a 50 μm square pattern opening in the center (see FIG. 2);
(ii) A hardened pattern (not shown) having a wall portion having a width of 300 μm corresponding to a pattern opening having a square of 100 μm in the center.

In addition, the protective film is peeled from the photosensitive film laminate 1 to expose the photosensitive film, and the exposed surface of the photosensitive film is bonded to the cured film pattern corresponding to the wall portion obtained as described above, and laminated by heating. The lamination was performed by heating the photosensitive film at 80 ° C. for 5 minutes while weighing 1.0 kg.

Next, the support film side of the photosensitive film laminate that is self-adhesive on the pattern of the cured film corresponding to the wall portion is sandwiched by the following (i) or (ii):
(i) a negative mask having a square opening pattern with a grid size of 50 μm (see FIG. 3);
(ii) A negative mask (not shown) having an opening pattern with a square lattice size of 100 μm.
For each example and each comparative example, a metal halide lamp was used to expose the photosensitive film with a combination of pattern openings and exposure amounts as described in Table 2. The supporting film was peeled to expose the photosensitive film. . In addition, exposure is performed through the laminated photosensitive film laminate as follows (i) or (ii).
(i) The 50 μm square pattern opening in the wall portion is overlapped with the 50 μm square pattern opening in the grid size of the negative mask (see FIG. 3);
(ii) The 100 μm square pattern opening in the wall portion is overlapped with the 100 μm square pattern opening in the grid size of the negative mask (not shown).
Then, regarding the exposed surface of the exposed photosensitive film, Examples 1 to 3 and Comparative Examples 1 and 2 were immersed in propylene glycol monomethyl ether acetate (PMA) at 23 ° C for 1 minute, and related In Example 4, a 1 wt% Na ₂ CO ₃ aqueous solution was developed at 30 ° C. and 2 MPa for 60 seconds, and Example 5 was developed at a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. and 2 MPa for 300 seconds. Each test substrate after development was sufficiently washed with water until no developing solution remained.

Continuing, each test substrate was heated at 200 ° C for 60 minutes to harden the photosensitive film, and by forming a hardened film pattern corresponding to the cover portion, a hollow structure having a wall portion and a cover portion was produced. Test substrate. In the obtained test substrate, although there was no 栉 -type electrode inside, the upper end of the wall portion was covered with a cover portion, and a hollow structure having the following (i) or (ii) was formed on the joint portion of the cover portion and the wall portion.
(i) 50 μm square pattern opening (refer to Figure 4);
(ii) 100 μm square pattern opening (not shown).

Example 2
In Example 1, a test substrate was produced in the same manner as in Example 1 except that the photosensitive composition 2 was used instead of the photosensitive composition 1 and the protective film 2 was used instead of the protective film 1. The arithmetic mean surface roughness Ra ′ and the maximum height Ry ′ of the protective film 2 were measured in the same manner as described above. Ra ′ was 0.46 μm, and the maximum height Ry ′ was 1.37 μm. And the protective film 2 was roll-shaped, and the inside surface of this winding was measured.

Example 3
In Example 1, a test substrate was produced in the same manner as in Example 1 except that the protective film 2 was used instead of the protective film 1.

Example 4
For Example 2, a test was made in the same manner as in Example 2 except that development with propylene glycol monomethyl ether acetate (PMA) was performed, except that a 1 wt% Na ₂ CO ₃ aqueous solution was developed at 30 ° C. and 2 MPa for 60 seconds. Substrate.

Example 5
For Example 4, instead of the photosensitive composition 2 The photosensitive composition 3 was used, and for 1wt% Na ₂ CO ₃ aq, 30 ℃ than 300 seconds and the developing 2MPa, and in the same manner as in Example 4 to prepare a test substrate.

Comparative Example 1
In Example 2, a test substrate was produced in the same manner as in Example 2 except that the photosensitive composition 4 was used instead of the photosensitive composition 2.

Comparative Example 2
In Example 1, a test substrate was produced in the same manner as in Example 1 except that the protective film 3 was used instead of the protective film 1. The arithmetic mean surface roughness Ra ′ and the maximum height Ry ′ of the protective film 3 were measured in the same manner as described above, and Ra ′ was 0.07 μm, and the maximum height Ry ′ was 0.98 μm. In addition, the protective film 3 is in the shape of a roll, and the inside surface of the winding is measured.

＜ Measurement of arithmetic average surface roughness Ra and maximum height Ry ＞
Each of the photosensitive film laminates (35mm × 20mm) used in Examples 1 to 5 and Comparative Examples 1 to 2 was placed on the surface of a clean glass substrate (76mm × 26mm × 1.1mmt) with a double-sided tape (KZ-12 (Manufactured by Nitoms Co., Ltd.) to adhere the glass substrate to the support film side of the photosensitive film, so that the glass substrate and the photosensitive film laminate are adhered.
Thereafter, the protective film of the photosensitive film laminate was peeled at a rate of 2.5 seconds / cm to the glass substrate at an angle of 90 ° to expose the photosensitive film. The arithmetic mean surface roughness Ra1 and the maximum height Ry1 of the photosensitive film surface exposed immediately after the protective film was peeled off (after 1 minute) were measured within 5 minutes immediately after the protective film was peeled. The measurement of Ra1 and Ry1 was performed as follows.

The "arithmetic average surface roughness Ra" of the exposed photosensitive film surface is the same as that used for measuring the arithmetic average surface roughness Ra 'of the protective film surface, and the sample is replaced with a protective film as the exposed photosensitive film. The measurement was performed in the same manner as described above, except for the substrate to which the thin film was bonded (with the exposed surface of the photosensitive film as the upper portion). In addition, the "maximum height Ry" of the exposed photosensitive film surface was also the same as that used to support the measurement of the maximum height Ry 'of the film surface, and the sample was replaced with a protective film, and the exposed photosensitive film was bonded together. The measurement was performed in the same manner as described above, except that the exposed surface of the photosensitive film was used as an upper portion. Table 2 shows the "arithmetic average surface roughness Ra1" and "maximum height Ry1" of the surface of each photosensitive film measured.

In addition, each measurement sample was subjected to a yellow light under a measurement environment (room temperature (23 ° C), relative humidity: 42% RH) in a state where the surface of the photosensitive film was exposed by peeling the protective film. After being left for 180 minutes, the arithmetic average surface roughness Ra and the maximum height Ry of the exposed surface of the photosensitive film were measured in the same manner as described above. Table 2 shows the "arithmetic average surface roughness Ra2" and "maximum height Ry2" of the surface of each photosensitive film.

＜ Evaluation of plating adhesion ＞
The test substrates of Examples 1 to 5 and Comparative Examples 1 to 2 prepared as described above were subjected to electroless copper plating. The plating conditions are as follows.
･ Electroless copper plating solution: Mel plate CU-390 (Meltex Co., Ltd.)
･ Plating solution temperature: 80 ℃
･ Plating time: 1 hour ･ Plating film thickness: 2.0μm
･ PH: 13.0 (room temperature)
After the plating treatment, each test substrate on which the electroless plating film was formed was washed with pure water at room temperature for 5 minutes, and then dried at 80 ° C. The cross section of the boundary between the wall portion of each test substrate and the electroless plated film was observed with an optical microscope and an electron microscope. The evaluation criteria are shown below.
：: No gap was generated, and there was no problem with adhesion ○: There were few gaps, but there was no problem with adhesion ×: There were gaps, and the evaluation results for the problem with adhesion are shown in Table 2 below.

From the results in Table 2, it was found that a hollow structure was formed using a photosensitive film laminate having an arithmetic average surface roughness of the surface of the photosensitive film set to Ra1 of 0.1 μm or more, and Ra2 / Ra1 of 0.40 or more and less than 1.00. In the test substrates 1 to 5 (Examples 1 to 5), the adhesion to the plating of the wall portion and the lid portion was high, and an electronic component having a high-quality hollow structure was obtained.
On the other hand, it was found that when a photosensitive film laminate having an arithmetic average surface roughness Ra1 of less than 0.1 μm was used to form a hollow structure on a test substrate 7 (Comparative Example 2), the Ra2 / Ra1 was 0.40. Above and below 1.00, the adhesion to the plating and sealing materials of the wall portion and the cover portion is insufficient.
In addition, it was found that even if the arithmetic average surface roughness Ra1 of the surface of the photosensitive film was 0.1 μm or more, a test substrate 6 having a hollow structure was formed using a photosensitive film laminate having a range of Ra2 / Ra1 of not less than 0.40 and not more than 1.00. In Comparative Example 1), the adhesion to the plating of the wall portion and the lid portion was insufficient.

[Fig. 1] A schematic cross-sectional view showing a procedure for producing a test substrate produced in Examples 4 and 5. [Fig.

[Fig. 2] A schematic cross-sectional view showing a procedure for producing test substrates produced in Examples 4 and 5. [Fig.

3 is a schematic cross-sectional view showing a procedure for producing a test substrate produced in Examples 4 and 5.

[Fig. 4] A schematic cross-sectional view showing a procedure for producing a test substrate produced in Examples 4 and 5. [Fig.

Claims (8)

A photosensitive film laminate comprising a support film, a photosensitive film formed of a photosensitive composition, and a protective film laminated in this order, wherein the photosensitive film laminate is peeled from the photosensitive film laminate. The protective film exposes the surface of the photosensitive film, and the arithmetic mean surface roughness of the surface of the photosensitive film is set to Ra1 after being left for 1 minute in an environment of 23 ° C. and a relative humidity of 42%. When the protective film is peeled off, the surface of the photosensitive film is exposed, and the arithmetic average surface roughness of the surface of the photosensitive film is set to Ra2 after being left for 180 minutes in an environment of 23 ° C and 42% relative humidity, the following formula is satisfied: . For example, the photosensitive film laminate of claim 1, wherein the protective film is peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and the photosensitive film laminate is left for 1 minute in an environment of 23 ° C and 42% relative humidity. The maximum height of the photosensitive film surface is set to Ry1. The protective film is peeled from the photosensitive film laminate to expose the surface of the photosensitive film, and the photosensitive film is left for 180 minutes in an environment of 23 ° C and 42% relative humidity. When the maximum height of the film surface is set to Ry2, the following formula is satisfied: . The photosensitive film laminate according to claim 1, wherein the photosensitive composition contains a photocurable compound. The photosensitive film laminate according to claim 1, wherein the photosensitive composition further contains a photopolymerization initiator. The photosensitive film laminate according to claim 1, which is used for forming a cover portion or a wall portion constituting the hollow structure in an electronic component having a hollow structure. A cured product obtained by curing the photosensitive film of the photosensitive film laminate according to any one of claims 1 to 5. An electronic part characterized by having a hardened body as claimed in claim 6. The electronic component according to claim 7 has a hollow structure formed of a wall portion and a cover portion, and one or both of the wall portion and the cover portion are formed of the hardened material.