JP2020169227A - Resin composition and method for manufacturing electronic device - Google Patents

Abstract

To provide a resin composition for forming a sacrificial layer, which can be preferably applied in a process of manufacturing an electronic device including laser grooving.SOLUTION: The resin composition comprises a resin and an ultraviolet ray absorbent and is non-photosensitive and used for forming a sacrificial layer in the manufacture of an electronic device. The ultraviolet ray absorbent is preferably an organic ultraviolet ray absorbent such as a benzophenone-based ultraviolet ray absorbent, a benzotriazole-based ultraviolet ray absorbent, and an anthracene-based ultraviolet ray absorbent. The resin is preferably a polymer having a non-aromatic cyclic skeleton in the main chain such as a polymer having a norbornene skeleton.SELECTED DRAWING: Figure 2

Description

The present invention relates to a resin composition and a method for manufacturing an electronic device. More specifically, the present invention relates to a resin composition used for forming a sacrificial layer in the manufacture of electronic devices, and a method for manufacturing an electronic device using the resin composition.

In the manufacture of electronic devices, a step of forming a sacrificial layer (a layer premised on being removed in a subsequent process) may be performed for various purposes. The sacrificial layer is usually formed using a resin composition.

As an example, in the examples of Patent Document 1, a resin obtained from 3,3'-diaminodiphenyl sulfone, meta-phenylenediamine, cyclobutanetetracarboxylic dianhydride or the like as a raw material is applied onto a wafer to provide a sacrificial layer. It is stated that.
As another example, Patent Document 2 describes forming a sacrificial layer for the protection of a sensor element in the manufacture of a sensor structure.

Japanese Unexamined Patent Publication No. 2016-004929 Japanese Unexamined Patent Publication No. 2008-528273

In the manufacture of electronic devices, a process called laser grooving may be performed.
Laser grooving refers to dicing a wafer using a blade, in which if there is a fragile layer such as a Low-k layer on the wafer, the fragile layer is burned off by a laser before dicing. As a result, peeling of the fragile layer can be suppressed during dicing with the blade.

With the further sophistication, complexity, and diversification of electronic device manufacturing in recent years, it is possible to dice a wafer having a sacrificial layer. It is also possible that the sacrificial layer may be burned off by laser grooving prior to the dicing.
However, as the findings of the present inventors, when the conventional sacrificial layer is subjected to laser grooving, there are cases where laser grooving cannot be performed appropriately. For example, the sacrificial layer may not be sufficiently burned off with a laser.

Therefore, the present inventors have studied one of the purposes of providing a resin composition for forming a sacrificial layer, which is preferably applicable to an electronic device manufacturing process including laser grooving.

As a result of diligent studies, the present inventors have completed the inventions provided below and solved the above problems.

According to the present invention
A resin composition used to form a sacrificial layer in the manufacture of electronic devices.
A non-photosensitive resin composition containing a resin and an ultraviolet absorber is provided.

Further, according to the present invention,
A sacrificial film forming step of forming a sacrificial film on a substrate by the above resin composition, and
A dry etching process for dry etching the sacrificial film and
An electronic device manufacturing method including the above is provided.

According to the present invention, there is provided a resin composition for forming a sacrificial layer, which is preferably applicable to an electronic device manufacturing process including laser grooving.

It is a schematic diagram for demonstrating the example of the electronic device manufacturing method including a laser grooving step. It is a schematic diagram for demonstrating the example of the electronic device manufacturing method including a laser grooving step.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In all drawings, similar components are designated by the same reference numerals, and description thereof will be omitted as appropriate.
In order to avoid complication, (i) when there are a plurality of the same components in the same drawing, only one of them is coded and all of them are not coded, or (ii) especially the figure. In 2 and later, the same components as in FIG. 1 may not be re-signed.
All drawings are for illustration purposes only. The shape and dimensional ratio of each member in the drawing do not necessarily correspond to the actual article.

In the present specification, the notation "a to b" in the description of the numerical range means a or more and b or less unless otherwise specified. For example, "1 to 5% by mass" means "1% by mass or more and 5% by mass or less".

In the notation of a group (atomic group) in the present specification, the notation that does not indicate whether it is substituted or unsubstituted includes both those having no substituent and those having a substituent. For example, the "alkyl group" includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
The notation "(meth) acrylic" herein represents a concept that includes both acrylic and methacrylic. The same applies to similar notations such as "(meth) acrylate".
Unless otherwise specified, the term "organic group" as used herein means an atomic group obtained by removing one or more hydrogen atoms from an organic compound. For example, the "monovalent organic group" represents an atomic group obtained by removing one hydrogen atom from an arbitrary organic compound.
The term "electronic device" as used herein refers to an element to which electronic engineering technology is applied, such as a semiconductor chip, a semiconductor element, a printed wiring board, an electric circuit display device, an information communication terminal, a light emitting diode, a physical battery, and a chemical battery. , Devices, final products, etc.

<Resin composition>
The resin composition of this embodiment is used to form a sacrificial layer in the manufacture of electronic devices.
The resin composition of the present embodiment contains a resin and an ultraviolet absorber, and is non-photosensitive.

The present inventors have investigated the cause of insufficient laser grooving (for example, the sacrificial layer cannot be sufficiently burned out by a laser) when the conventional sacrificial layer is subjected to laser grooving.
As a result of the examination, the conventional sacrificial layer has low absorption of ultraviolet laser light (usually, wavelength 355 nm) usually used in laser grooving, so that heat generation due to laser irradiation is small, and therefore, laser grooving can be performed appropriately. It was thought that it could not be done.
Therefore, the present inventors have included an ultraviolet absorber in the resin composition so as to appropriately absorb the laser light having a wavelength of 355 nm. According to this design, the cured film (sacrificial layer) formed of the resin composition appropriately absorbs the laser beam to generate heat, and good laser grooving is possible.

Since the resin composition of the present embodiment is non-photosensitive, it cannot be precisely patterned by photolithography. However, depending on the purpose of providing the sacrificial layer and the structure of the electronic device, the non-photosensitivity does not pose a particular problem. Being non-photosensitive also leads to the merit that outgassing and contamination due to decomposition of the photosensitive agent are unlikely to occur.
The resin composition of the present embodiment is designed to absorb laser light having a wavelength of 355 nm by using an ultraviolet absorber even though it is non-photosensitive. In this respect, the resin composition of the present embodiment can be said to be a resin composition based on an unprecedented technical idea.

The components and properties of the resin composition of the present embodiment will be described more specifically.

(resin)
The resin composition of the present embodiment contains a resin.
The resin preferably comprises a polymer having a non-aromatic cyclic skeleton in the main chain. Hereinafter, this polymer is also referred to as "specific polymer".

The specific polymer has a rigid chemical structure derived from the non-aromatic cyclic skeleton of the main chain. It is considered that this makes it possible to further increase the heat resistance of the sacrificial layer.
Further, the non-aromatic cyclic skeleton of the main chain tends to have a relatively high etching rate as compared with the aromatic ring structure, etc., while being rigid. Therefore, as compared with, for example, the resin composition described in Patent Document 1 (including the polyimide resin containing an aromatic ring structure), it is considered that the resin composition of the present embodiment has a large etching rate and is easy to design. A high etching rate means that it is easy to remove by etching, which is a preferable property as a resin composition for forming a sacrificial layer, which must be removed after use.

The specific polymer preferably contains a structural unit represented by the following general formula (NB). When the specific polymer contains this structural unit, the rigidity of the polymer as a whole becomes appropriate. Therefore, the heat resistance of the sacrificial layer can be further increased.

In the general formula (NB),
R ¹ , R ² , R ³ and R ⁴ are independently hydrogen atoms or organic groups having 1 to 30 carbon atoms.
a ₁ is 0, 1 or 2.

The organic groups having 1 to 30 carbon atoms of R ¹ , R ² , R ³ and R ^{4 in} the general formula (NB) include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group and an alkalil group. , Cycloalkyl group, alkoxy group, heterocyclic group, carboxyl group and the like.

Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group and heptyl group. Examples thereof include an octyl group, a nonyl group and a decyl group.
Examples of the alkenyl group include an allyl group, a pentenyl group, a vinyl group and the like.
Examples of the alkynyl group include an ethynyl group.
Examples of the alkylidene group include a methylidene group and an ethylidene group.
Examples of the aryl group include a tolyl group, a xsilyl group, a phenyl group, a naphthyl group, and an anthrasenyl group.
Examples of the aralkyl group include a benzyl group and a phenethyl group.
Examples of the alkaline group include a tolyl group and a xylyl group.
Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group and the like.
Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, an isobutoxy group, a tert-butoxy group, an n-pentyloxy group and a neopentyloxy group. , N-hexyloxy group and the like.
Examples of the heterocyclic group include an epoxy group and an oxetanyl group.

In the general formula ^{(NB), R 1, R} 2, preferably a hydrogen or an alkyl group as ^{R 3} and ^{R 4,} hydrogen is more preferable.
The hydrogen atoms in the organic groups having 1 to 30 carbon atoms of R ¹ , R ² , R ³ and R ⁴ may be substituted with arbitrary atomic groups. For example, it may be substituted with a fluorine atom, a hydroxyl group, a carboxyl group, or the like. More specifically, an alkyl fluoride group or the like may be selected as the organic group having 1 to 30 carbon atoms of R ¹ , R ² , R ³ and R ⁴ .
In the general formula (NB), _{a 1} is preferably 0 or 1, more preferably 0.

As another aspect, the specific polymer may contain a structural unit represented by the following general formula (NB-2). This structural unit, like the structural unit represented by the general formula (NB), is particularly effective in increasing the heat resistance of the sacrificial layer.
In the general formula (NB-2), the definitions and specific embodiments of R ¹ , R ² , R ³ , R ⁴ and a ₁ are the same as those in the general formula (NB).

The ratio of the structural unit derived from the cyclic olefin monomer (specifically, the structural unit represented by the above general formula (NB) or (NB-2)) in the total structural unit of the specific polymer is, for example, 10 to 100 mol. %, Preferably 20-80 mol%, more preferably 45-55 mol%.
When the specific polymer contains both the structural unit represented by the general formula (NB) and the structural unit represented by the general formula (NB-2), it is preferable that the total thereof is in the above range.

The specific polymer preferably contains a structural unit derived from a cyclic acid anhydride monomer having a carbon-carbon double bond. Specific examples of this structural unit include a structural unit represented by the following formula (MA).
The structural unit represented by the formula (MA) contains an oxygen atom in its structure. Therefore, by including this structural unit in the polymer, it is easy to design a relatively large removability of the sacrificial layer by dry etching (O ₂ plasma etching).

The ratio of the structural unit (specifically, the structural unit represented by the formula (MA)) derived from the cyclic acid anhydride monomer having a carbon-carbon double bond in the total structural unit of the specific polymer is, for example, 10 to 10. It is 50 mol%, preferably 20 to 50 mol%, and more preferably 40 to 50 mol%.

The specific polymer may contain a third structural unit that is different from the structural unit derived from the above-mentioned cyclic olefin monomer and the structural unit derived from the cyclic acid anhydride monomer having a carbon-carbon double bond. For example, a third structural unit may be contained in the polymer for the purpose of controlling the reactivity with the cross-linking agent described later.
Examples of the third structural unit include structural units represented by the following general formulas (a2-1), (a2-2) or (a2-3).
In the general formula (a2-1) and the general formula (a2-2), R ₁₄ , R ₁₅ and R ₁₆ are independently organic groups having 1 to 30 carbon atoms, respectively.

The organic groups having 1 to 30 carbon atoms constituting R ₁₄ , R ₁₅ and R ₁₆ may contain any one or more of O, N, S, P and Si in the structure. Further, the organic groups constituting R ₁₄ , R ₁₅ and R ₁₆ can be free of acidic functional groups. This makes it easy to control the acid value.

Examples of the organic group constituting R ₁₄ , R ₁₅ and R ₁₆ include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkalil group, a cycloalkyl group, and a heterocyclic group.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group and heptyl group. , Octyl group, nonyl group, decyl group and the like.
Examples of the alkenyl group include an allyl group, a pentaenyl group, a vinyl group and the like.
Examples of the alkynyl group include an ethynyl group and the like.
Examples of the alkylidene group include a methylidene group and an ethylidene group.
Examples of the aryl group include a phenyl group, a naphthyl group, an anthracenyl group and the like.
Examples of the aralkyl group include a benzyl group and a phenethyl group.
Examples of the alkaline group include a tolyl group and a xylyl group.
Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group and the like.
Examples of the heterocyclic group include an epoxy group and an oxetanyl group.

In these alkyl group, alkenyl group, alkynyl group, alkylidene group, aryl group, aralkyl group, alkalil group, cycloalkyl group, and heterocyclic group, one or more hydrogen atoms may be substituted with halogen atoms. Halogen atoms include fluorine, chlorine, bromine, and iodine. Of these, a haloalkyl group in which one or more hydrogen atoms of the alkyl group are substituted with halogen atoms is preferable.
The polymer preferably contains at least the structural units represented by the general formula (a2-1) and / or the general formula (a2-3).
The polymer may contain only one of the structural units represented by the general formulas (a2-1), (a2-2) or (a2-3), or may contain two or more. Of course, the polymer does not have to contain these structural units.

As a supplement, the structural unit represented by the general formula (a2-1), (a2-2) or (a2-3) can be introduced into the specific polymer, for example, as follows.
(I) First, the structural unit represented by the above formula (MA) is introduced into the specific polymer.
(Ii) The structural unit is then ring-opened by appropriate means.

More specifically, regarding the above (ii), for example, the structural unit represented by the formula (MA) is formed by the action of a monohydric alcohol on the structural unit represented by the formula (MA) in the specific polymer. Changes to the structural unit represented by the general formula (a2-1).

Of course, in the polymerization of a specific polymer, by using a monomer that directly corresponds to the structural unit represented by the general formula (a2-1), (a2-2) or (a2-3), it is generally possible to use the monomer in the polymer. The structural unit represented by the formula (a2-1), (a2-2) or (a2-3) may be introduced.

Examples of the third structural unit that can be mentioned in addition to the structural units represented by the general formulas (a2-1), (a2-2) or (a2-3) include (i) (meth) acrylic acid monomer. There are structural units from which they are derived, and (ii) structural units in which at least one of R ^{1 to} R ^{4 in} the general formula (NB) or (NB-2) is a carboxy group or a hydroxy group.

The specific polymer may contain only one type of the third structural unit as described above, or may contain two or more types.
When the specific polymer contains a third structural unit, the content ratio thereof is, for example, 10 to 80 mol%, preferably 20 to 60 mol%, based on all the structural units in the polymer.

From the viewpoint of obtaining an appropriate etching rate, the resin preferably does not contain an aromatic structure, or even if it contains a small amount. Specifically, the proportion of the structural unit containing the aromatic structure in the resin is, for example, 50 mol% or less, preferably 30 mol% or less, more preferably 10 mol% or less, still more preferably 5 mol% or less, and particularly preferably 0. ..

When the resin contains two or more structural units, the resin may be a random copolymer, a block copolymer, or an alternating copolymer.
The resin can be produced by applying a known polymer synthesis technique, specifically, a known technique related to radical polymerization or catalytic polymerization. More specifically, for example, the description in JP-A-2017-9915 and the synthesis example described in Japanese Patent No. 5618537 can be referred to.

The weight average molecular weight (Mw) of the resin is, for example, 3000 to 30000, preferably 6000 to 20000. Mw can be measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

(UV absorber)
The resin composition of the present embodiment preferably contains an ultraviolet absorber. Thereby, the transmittance of light having a wavelength of 355 nm can be highly controlled. Then, the suitability for laser grooving can be further enhanced.

The UV absorber that can be used is not particularly limited. Any one capable of controlling the transmittance of light having a wavelength of 355 nm can be used.
The UV absorber is not an inorganic particle but an organic compound from the viewpoint of compatibility with a polymer or a cross-linking agent and removability by subsequent etching (the UV absorber is an organic UV absorber). ) Is preferable.

More specific examples of the ultraviolet absorber include benzophenone compounds, benzotriazole compounds, anthracene compounds, and triazine compounds. These are preferable from the viewpoints of ease of control of the transmittance of light having a wavelength of 355 nm, compatibility with polymers and cross-linking agents, and availability.

Specific examples of the benzophenone compound include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2,2'-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, and the like. 2,2'-Dihydroxy-4,4'-dimethoxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone and the like can be mentioned.

Specific examples of the benzotriazole-based compound include 2- (2H-benzotriazole-2-yl) -4-methyl-6- (3,4,5,6-tetrahydrophthalibidylmethyl) phenol and 2- (2H). -Benzotriazole-2-yl) -p-cresol, 2- (2H-benzotriazole-2-yl) -4-tert-butylphenol, 2- (2H-benzotriazole-2-yl) -4,6-di -Tert-Butylphenol, 2- (2H-benzotriazole-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2- (2H-benzotriazole-2-yl) -4- (1,1,3,3-Tetramethylbutyl) -6- (1-methyl-1-phenylethyl) phenol, 2- (2H-benzotriazole-2-yl) -4- (3-on-4-) Oxa-dodecyl) -6-tert-butyl-phenol, 2- {5-chloro (2H) -benzotriazole-2-yl} -4- (3-one-4-oxadodecyl) -6-tert-butyl -Pharmon, 2- {5-chloro (2H) -benzotriazole-2-yl} -4-methyl-6-tert-butyl-phenol, 2- (2H-benzotriazole-2-yl) -4,6- Di-tert-pentylphenol, 2- {5-chloro (2H) -benzotriazole-2-yl} -4,6-di-tert-butylphenol, 2- (2H-benzotriazole-2-yl) -4- tert-octylphenol, 2- (2H-benzotriazole-2-yl) -4-methyl-6-n-dodecylphenol, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) ) -6-[(2H-benzotriazole-2-yl) phenol]] and the like.

Specific examples of anthracene compounds include anthracene, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dipropoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, and 2-ethyl-9. , 10-Diethoxyanthracene, 2-ethyl-9,10-dipropoxyanthracene, 4'-nitrobenzyl-9,10-dimethoxyanthracene-2-sulfonate, 4'-nitrobenzyl-9,10-diethoxyanthracene- 2-sulfonate, 4'-nitrobenzyl-9,10-dipropoxyanthracene-2-sulfonate and the like can be mentioned.

Specific examples of triazine compounds include 2- (4-phenoxy-2-hydroxy-phenyl) -4,6-diphenyl-1,3,5-triazine and 2- (2-hydroxy-4-oxa-hexade). Syroxy) -4,6-di (2,4-dimethyl-phenyl) -1,3,5-triazine, 2- (2-hydroxy-4-oxa-heptadecyloxy) -4,6-di (2,4-di) Dimethyl-phenyl) -1,3,5-triazine, 2- (2-hydroxy-4-iso-octyloxy-phenyl) -4,6-di (2,4-dimethyl-phenyl) -1,3,5- Examples thereof include triazine, 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine.

A commercially available product may be used as the ultraviolet absorber. Examples of commercially available products include the Uvinul (registered trademark) series of BASF, RUVA-93 of Otsuka Chemical Co., Ltd., and the Antracure (registered trademark) series of Kawasaki Kasei Chemicals, Inc. For reference, some of the "sensitizers" known in the field of photosensitive resin compositions can appropriately absorb light having a wavelength of 355 nm and can be used as an ultraviolet absorber in the present embodiment. ..

When the resin composition of the present embodiment contains an ultraviolet absorber, it may contain only one type of ultraviolet absorber or two or more types.
The proportion of the ultraviolet absorber in the resin composition of the present embodiment is preferably 0.1 to 30% by mass, more preferably 0.5 to 20% by mass, still more preferably 1 in the total solid content of the resin composition. It is 10% by mass. By adjusting the proportion of the UV absorber in the composition, it is possible to optimize the absorbency of light having a wavelength of 355 nm while maintaining other performances, and further enhance the laser grooving suitability.
(The "total solid content" of the resin composition means a non-volatile component in the resin composition. Usually, the total solid content of the resin composition refers to a component other than the organic solvent in the resin composition. )

(Crosslinking agent)
The resin composition of the present embodiment preferably contains a cross-linking agent. Thereby, for example, the heat resistance of the cured film (sacrificial layer) can be further enhanced.

The cross-linking agent typically contains two or more cross-linking groups in one molecule. As a result, a crosslinked structure for connecting the polymers is formed, and the heat resistance of the cured film (sacrificial layer) is further enhanced.
The number of crosslinkable groups contained in one molecule of the crosslinking agent is usually 2 to 8, preferably 2 to 6, and more preferably 2 to 4. By appropriately selecting this number, the crosslinked structure can be controlled and various performances can be enhanced.
Examples of the crosslinkable group include an alkoxymethyl group, a methylol group, a hydroxy group, an epoxy group, an oxetanyl group, an isocyanate group and a maleimide group.

As the cross-linking agent, at least one selected from the group consisting of an epoxy compound, an oxetane compound and a polyol compound is preferable. The detailed mechanism is not clear, but probably the reactivity or reaction temperature of these compounds exactly matches the curing conditions (temperature conditions) in the manufacture of electronic devices, which leads to better heat resistance and curing shrinkage. It is presumed that it will lead to the reduction of.

Examples of the epoxy compound include known epoxy resins.
Examples of the epoxy resin include epoxy resins having two or more epoxy groups in one molecule. As the epoxy resin, monomers, oligomers, and polymers in general can be used. The molecular weight and molecular structure of the epoxy resin are not particularly limited.
Examples of the epoxy resin include phenol novolac type epoxy resin, cresol novolac type epoxy resin, cresol naphthol type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, phenoxy resin, naphthalene skeleton type epoxy resin, and bisphenol A type epoxy resin. , Bisphenol A diglycidyl ether type epoxy resin, bisphenol F type epoxy resin, bisphenol F diglycidyl ether type epoxy resin, bisphenol S diglycidyl ether type epoxy resin, glycidyl ether type epoxy resin, cresol novolac type epoxy resin, aromatic polyfunctional Examples thereof include epoxy resins (for example, polyfunctional epoxy resins having a fluorene skeleton), aliphatic epoxy resins, aliphatic polyfunctional epoxy resins, alicyclic epoxy resins, and polyfunctional alicyclic epoxy resins.

Further, as the epoxy resin, a polyfunctional epoxy resin having three or more functionalities (that is, one having three or more epoxy groups in one molecule) can also be mentioned. As the polyfunctional epoxy resin, those having 3 to 20 functionalities are more preferable. By using a trifunctional or higher functional epoxy resin, the heat resistance of the cured film tends to be further enhanced.
Examples of the polyfunctional epoxy resin include 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4-([2,3-epoxypropoxy] phenyl)). Ethyl] phenyl] propane, phenol novolac type epoxy, tetrakis (glycidyloxyphenyl) ethane, α-2,3-epoxypropoxyphenyl-ω-hydropoly (n = 1-7) {2- (2,3-epoxypropoxy) Bendilidene-2,3-epoxypropoxyphenylene}, 1-chloro-2,3-epoxypropane, formaldehyde, 2,7-naphthalenediol polycondensate, dicyclopentadiene type epoxy resin and the like can be mentioned.

Phenoxy resin (polyhydroxypolyester synthesized from bisphenols and epichlorohydrin) can also be preferably mentioned as a kind of epoxy compound. By using the phenoxy resin, the heat resistance of the cured film tends to be improved.
Examples of the phenoxy resin include bisphenol A type phenoxy resin, bisphenol F type phenoxy resin, bisphenol A type and bisphenol F type copolymerized phenoxy resin, biphenyl type phenoxy resin, bisphenol S type phenoxy resin, biphenyl type phenoxy resin and bisphenol. Examples thereof include a phenoxy resin copolymerized with an S-type phenoxy resin. Of these, a bisphenol A type phenoxy resin or a copolymerized phenoxy resin of a bisphenol A type and a bisphenol F type is preferable.
The weight average molecular weight of the phenoxy resin is preferably 1000 to 10000, more preferably 1000 to 5000. The weight average molecular weight is measured, for example, as a polystyrene-equivalent value by gel permeation chromatography (GPC).
The phenoxy resin may be used alone or in combination of two or more.

The oxetane compound is not particularly limited as long as it is a compound having an oxetane group.
For example, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, bis [1-ethyl (3-oxetanyl)] methyl ether, 4,4'-bis [(3-ethyl-3). -Oxetanyl) methoxymethyl] biphenyl, 4,4'-bis (3-ethyl-3-oxetanylmethoxy) biphenyl, ethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, diethylene glycol bis (3-ethyl-3-3) Oxetanylmethyl) ether, bis (3-ethyl-3-oxetanylmethyl) diphenoate, trimethylpropanthris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, poly [[3-[(3-Ethyl-3-oxetanyl) methoxy] propyl] silaseskioxane] derivative, oxetanyl silicate, phenol novolac-type oxetane, 1,3-bis [(3-ethyloxetane-3-yl) methoxy] Examples include benzene.

The polyol compound is not particularly limited as long as it is a compound having two or more hydroxy groups in one molecule.
The polyol compound can include, for example, a compound represented by the following general formula (PO).

In the general formula (PO),
n is 2 or more,
A plurality of R ⁵ are each independently a linear or branched alkylene group having 2 to 8 carbon atoms,
Each of the plurality of Xs is independently selected from the group consisting of a carbonate group (-O- (C = O) -O-), an ester group (-COO- or -OCO-) and an ether group (-O-). Is either
R ⁶ is a linear or branched alkylene group having 2 to 8 carbon atoms.

n is not particularly limited as long as it is 2 or more. There is no particular upper limit, but the upper limit is, for example, 300.

In the general formula (PO), at least one of the plurality of Xs is preferably a carbonate group. More preferably, all of the plurality of Xs are carbonate groups.

R ⁵ and R ⁶ are not particularly limited as long as they are linear or branched alkylene groups having 2 to 8 carbon atoms.
Ease and availability of the compound, from the viewpoint of appropriate flexibility, the carbon number of R ⁵ is preferably 4-7, more preferably 5-6. The number of carbon atoms of R ⁶ is the same.
Examples of the linear or branched alkylene group having 2 to 8 carbon atoms include − (CH ₂ ) ₂ −, − (CH ₂ ) ₃ −, − (CH ₂ ) ₄ −, − (CH ₂ ) ₅ −, − (CH ₂ ) ₆ −, −C (CH ₃ ) ₂ −, −CH ₂ −CH (CH ₃ ) −, −CH ₂ −CH (CH ₃ ) −CH ₂ −, −CH ₂ −C ( CH ₃ ) _2- CH _2- and the like can be mentioned.
Particularly preferably, R ¹ is − (CH ₂ ) _5- or − (CH ₂ ) ₆ −. The same applies to R ² .

R ⁵ and R ⁶ may have substituents as long as the effects of the invention are not excessively impaired. Examples of the substituent include a halogen atom, a hydroxy group, an alkoxy group and the like. Of course, R ¹ and R ² may be unsubstituted.

The molecular weight of the polyol compound (weight average molecular weight if there is a molecular weight distribution) is, for example, 300 to 6000, preferably 350 to 5000, and more preferably 400 to 4000.

As the polyol compound, a commercially available product may be used. Specifically, commercially available compounds such as "polycarbonate diol", "polyester polyol", and "polyether diol" can be used.
As an example, ETERNAL COLL (registered trademark) UH-50, UH-100, UH-200, UH-300, PH-50, PH-100, PH-200, PH-300 and the like sold by Ube Industries, Ltd. can be mentioned. Can be (these are polycarbonate diols).
As another example, the product name Duranol series (polycarbonate diol) manufactured by Asahi Kasei Chemicals, the product name BENEBiOL series (polycarbonate diol) manufactured by Mitsubishi Chemical Co., Ltd., and the product name Clare polyol (polycarbonate diol and polyester polyol) manufactured by Kuraray Co., Ltd. are lined up. (Uploaded) etc. can also be mentioned.
As yet another example, the lineup includes AGC's trade name Excelol (polyetherdiol), DIC's trade name Polylite series (polyesterdiol), and ADEKA's trade name Adecapolyether (polyesterdiol and polyester polyol). ) Etc. can also be mentioned.

As the polyether diol, among so-called polyethylene glycols and polypropylene glycols, those having hydroxyl groups at both ends can be appropriately used.

When the resin composition of the present embodiment contains a cross-linking agent, it may contain only one type of cross-linking agent or two or more types.
In the resin composition of the present embodiment, the amount of the cross-linking agent is preferably 25 to 150 parts by mass, more preferably 30 to 120 parts by mass, and further preferably 40 to 100 parts by mass with respect to 100 parts by mass of the resin. By using an appropriate amount of the cross-linking agent, it is possible to obtain merits such as a smaller curing shrinkage rate.

(Surfactant)
The resin composition of the present embodiment may contain a surfactant. Thereby, the uniformity of the film at the time of film formation can be improved.

The surfactant is preferably a nonionic surfactant containing at least one of a fluorine atom and a silicon atom.
Commercially available surfactants include, for example, F-251, F-253, F-281, F-430, F-477, F-551, and F-552 of the "Mega Fvck" series manufactured by DIC Co., Ltd. , F-555, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F-565, F Contains fluorine such as -568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, etc. Surfactants with an oligomeric structure, Fluorine-containing nonionic surfactants such as Futtergent 250 and Futtergent 251 manufactured by Neos Co., Ltd., SILFOAM® series manufactured by Wacker Chemie (for example, SD 100 TS, SD 670) , SD 850, SD 860, SD 882) and other silicone-based surfactants.

When the resin composition of the present embodiment contains a surfactant, the resin composition may contain only one type of surfactant, or may contain two or more types of surfactant.
When the resin composition of the present embodiment contains a surfactant, the amount thereof is preferably 0.005 to 1 part by mass and 0.02 to 0.5 part by mass with respect to 100 parts by mass of the polymer. Is more preferable.

(solvent)
The resin composition of the present embodiment preferably contains a solvent. In other words, the resin composition of the present embodiment is preferably one in which each component is dissolved or dispersed in a solvent. The solvent facilitates the formation of a film of the resin composition.

The solvent is typically an organic solvent. Specific examples thereof include organic solvents such as ketone solvents, ester solvents, ether solvents, alcohol solvents, lactone solvents, and carbonate solvents.

More specifically, acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, butyl acetate, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate. , Benzyl alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, anisole, N-methylpyrrolidone, cyclohexanone, cyclopentanone, decane and other organic solvents.

When the resin composition of the present embodiment contains a solvent, the resin composition may contain only one type of solvent, or may contain two or more types of solvent. That is, the solvent may be a single solvent or a mixed solvent.
When the resin composition of the present embodiment contains a solvent, the amount thereof is not particularly limited, but the concentration of the non-volatile component in the composition is, for example, 10 to 70% by mass, preferably 15 to 60% by mass. used. By appropriately adjusting the amount of the solvent, for example, the film thickness when the resin composition is applied onto the substrate to form a film can be adjusted.

(Other ingredients)
The resin composition of the present embodiment may contain various components other than the above as long as it is applicable to the electronic device manufacturing process including laser grooving. Examples of such components include antioxidants, fillers and the like. However, from the viewpoint of preventing unintended contamination of electronic devices, the resin composition of the present embodiment preferably does not contain a colorant such as a dye or a pigment.

(About adhesion aid)
The resin composition of the present embodiment may contain an adhesion aid such as a silane coupling agent. However, from the viewpoint of reducing the residue after etching, the resin composition of the present embodiment preferably does not contain a Si-containing compound such as a silane coupling agent, or even if it contains a small amount.

Specifically, the amount of the silane coupling agent in the total solid content of the resin composition of the present embodiment is preferably 5% by mass or less, more preferably 1% by mass or less. More preferably, the resin composition of the present embodiment does not contain a silane coupling agent.
As another viewpoint, the amount of the total Si-containing compound in the total solid content of the resin composition of the present embodiment is preferably 5% by mass or less, more preferably 1% by mass or less. More preferably, the resin composition of the present embodiment does not contain a Si-containing compound.

(About photosensitive / photosensitive agent)
The resin composition of this embodiment is non-photosensitive. In other words, even if the resin film formed of the resin composition of the present embodiment is irradiated with g-rays or i-rays, the solubility in an alkaline aqueous solution does not substantially change.
The resin composition of the present embodiment usually contains a photosensitive agent such as a quinonediazide compound or a photosensitive onium salt, that is, a compound that generates chemical species such as acids, alkalis, and radicals when irradiated with light such as ultraviolet rays. Not included.

(About light transmission / absorption)
Since the resin composition of the present embodiment contains an ultraviolet absorber, the transmittance of ultraviolet light when formed into a cured film is reduced. Quantitatively expressing the transmittance, the transmittance of light at a wavelength of 355 nm per 25 μm thickness of the cured film obtained by heating the resin composition of the present embodiment at 200 ° C. for 90 minutes in a nitrogen atmosphere is , Preferably 50% or less. This transmittance is more preferably 20% or less, still more preferably 10% or less.
There is no particular lower limit for transmittance. The transmittance of light having a wavelength of 355 nm may be 0%. By the way, since laser grooving is to "burn off" the resin film with a laser, the resin film is gradually burned out from the upper surface even if the light transmittance is 0% (light does not reach the lower part of the resin film). That doesn't mean you can't laser grooving).

The transmittance of light "per 25 μm film thickness" will be described just in case.
When the transmittance is measured with a cured film having a film thickness of 25 μm, the numerical value obtained by the measurement can be adopted as it is. From the viewpoint of minimizing various errors, it is preferable that the transmittance is measured with a cured film having a film thickness of 25 μm.

When the transmittance is measured with a cured film having a film thickness of not 25 μm, it is as follows.
According to Lambert-Beer's law, the absorbance A calculated from the incident light intensity and the transmitted light intensity is proportional to the optical path length L of the medium. Therefore, the absorbance A _{25 μm} “per 25 μm film thickness” can be expressed as A × (L / 25) (the unit of L is μm).
Here, since the absorbance A and the transmittance T have a relationship of A = -logT, if the value of A _{25 μm} is substituted into this relational expression and calculated for T, the light transmittance per film thickness 25 μm is calculated. Can be calculated.

As another viewpoint, the transmittance of light having a wavelength of 633 nm per 25 μm film thickness of the cured film obtained by heating the resin composition of the present embodiment at 200 ° C. for 90 minutes in a nitrogen atmosphere is preferably 80%. Above, more preferably 85% or more.
In the manufacture of electronic devices, light having a wavelength of 633 nm may be used for wafer alignment and the like. In this respect, the cured film preferably transmits light having a wavelength of 633 nm and its peripheral wavelengths well.

(About heat resistance)
The resin composition of the present embodiment is preferably able to withstand various heating processes (that is, has good heat resistance) as a resin composition used for forming a sacrificial layer in the manufacture of electronic devices. The heat resistance can be quantitatively evaluated by the glass transition temperature of the cured product obtained by curing the resin composition with heat.

Specifically, the glass transition temperature obtained by thermomechanical analysis (Thermomechanical Analysis) of a cured film obtained by heating the resin composition of the present embodiment at 200 ° C. for 90 minutes in a nitrogen atmosphere is preferable. Is 150 ° C. or higher, more preferably 170 ° C. or higher. In other words, by designing the resin composition so that the glass transition temperature obtained by the above procedure is 150 ° C. or higher, a resin composition for forming a sacrificial layer having better heat resistance can be obtained.
There is no particular upper limit to the glass transition temperature, but it is 300 ° C. or lower from the viewpoint of appropriate flexibility of the cured film.

<Electronic device manufacturing method>
An electronic device can be manufactured by a step including a sacrificial layer forming step of forming a sacrificial layer on a substrate by the resin composition of the present embodiment and a dry etching step of dry etching the sacrificial layer.
For example, the resin composition of the present embodiment can be used in the production of a device including a sacrificial layer forming step as disclosed in the above-mentioned Patent Documents 1 and 2. The sacrificial layer after completing the role as a sacrificial layer (protection of members on the substrate, formation of a hollow structure, etc.) is relatively easily removed by dry etching using O ₂ gas.

As already described, the resin composition of the present embodiment is particularly preferably applicable to an electronic device manufacturing process including laser grooving. Specifically, the resin composition of the present embodiment is preferably applied to an electronic device manufacturing method including a laser grooving step of performing laser grooving on the sacrificial layer between the sacrificial layer forming step and the dry etching step. be able to.

An example of an electronic device manufacturing method including a laser grooving step will be specifically described with reference to FIG.

First, as shown in FIG. 1A, a sacrificial layer 5 made of the resin composition of the present embodiment is formed on a part or all of one surface of the substrate 1 (sacrificial layer forming step).

The substrate 1 is not particularly limited. Examples of the substrate 1 include a silicon wafer, a ceramic substrate, an aluminum substrate, a SiC substrate, a SiC substrate, a GaN substrate, and the like. The substrate 1 may be an unprocessed substrate or a substrate including elements and / or wiring.

The method for forming (forming) the sacrificial layer 5 is not particularly limited, and a known method can be appropriately applied. The spin coating method is usually applied in the manufacture of electronic devices. A bar coating method, a slit coating method, a spray method, an inkjet method, or the like may be applied depending on the size of the substrate area.
When the sacrificial layer 5 is formed (film-formed), it may be dried by heating. Drying is typically carried out by heat treatment on a hot plate, hot air, an oven or the like. The heating temperature is usually 80 to 140 ° C, preferably 90 to 120 ° C. The heating time is usually about 30 to 600 seconds, preferably about 30 to 300 seconds.
The film thickness at the time of film formation is not particularly limited, and may be appropriately adjusted depending on the structure of the electronic device to be finally obtained. The film thickness at the time of film formation is, for example, about 5 to 50 μm.
The formed sacrificial layer 5 is preferably thermoset by heating. The conditions for thermosetting can be, for example, about 150 to 350 ° C. for about 10 minutes to 3 hours.

Next, as shown in FIG. 1B, the sacrificial layer 5 is irradiated with the laser beam 10 to burn off a part of the sacrificial layer 5 to form a “groove”. This process is laser grooving in a narrow sense. By forming the sacrificial layer 5 with the resin composition of the present embodiment, a part of the sacrificial layer 5 can be appropriately burned off.
The wavelength of the laser beam 10 is typically 355 nm. The output of the laser, the frequency when the laser is a pulse laser, the speed at which the laser is moved, and the like are not particularly limited. Arbitrary conditions can be adopted as long as laser grooving is possible. For an example of the conditions, refer to Examples described later.
Specifically, the laser grooving may be a method of forming two fine grooves (grooves) known as π laser grooving, ω laser grooving, and the like.

After the groove is formed in the sacrificial layer 5, the dicing blade 11 is applied to the groove portion to dice the substrate 1 (FIGS. 1C and 1D). Known techniques can be appropriately applied to the dicing blade 11 that can be used and the specific method of dicing.

After dicing, a dry etching step is performed in which the sacrificial layer 5 remaining on the cut substrate 1 is removed by dry etching. The gas used for dry etching is typically O ₂ . The specific conditions for dry etching, the apparatus for performing dry etching, and the like are not particularly limited as long as the sacrificial layer 5 can be removed, and known techniques can be appropriately applied.

An example of an electronic device manufacturing method including a laser grooving step, which is different from FIG. 1, will be specifically described with reference to FIG. 2 (the portion different from FIG. 1 will be mainly described).
The electronic device manufacturing method shown in FIG. 2 is different from the manufacturing method of FIG. 1 in that an intermediate layer 3 exists between the substrate 1 and the sacrificial layer 5. In other words, in the sacrificial layer forming step, the sacrificial layer is formed on the intermediate layer 3 of the substrate including the intermediate layer 3 (particularly see FIG. 2A).
The intermediate layer 3 is a permanent film such as a polyimide film.

In the laser grooving step shown in FIG. 2B, both the intermediate layer 3 and the sacrificial layer 5 can be laser grooved at once to form a groove.
As the findings of the present inventors, the transmittance of the sacrificial layer 5 formed by the resin composition of the present embodiment at a wavelength of 355 nm is about the same as that of the polyimide film. Therefore, it is considered that both the intermediate layer 3 and the sacrificial layer 5 can be burnt off cleanly (without noticeable peeling) by one laser irradiation.

The dicing process shown in FIGS. 2C and 2D and the dry etching process shown in FIG. 2E are basically the same as those described in FIGS. 1C, 1D and 1E, except that the intermediate layer 3 is present. is there. Therefore, I will omit the explanation again.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above can be adopted. Further, the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the range in which the object of the present invention can be achieved are included in the present invention.

Embodiments of the present invention will be described in detail based on Examples and Comparative Examples. The present invention is not limited to the examples.
<Synthesis of resin>
[Synthesis Example 1: Synthesis of Polymer 1]
Maleic anhydride (122.4 g, 1.25 mol), 2-norbornene (117.6 g, 1.25 mol) and dimethyl 2,2'-azobis (122.4 g, 1.25 mol) in an appropriately sized reaction vessel equipped with a stirrer and a condenser. 2-Methylpropionate) (11.5 g, 50.0 mmol) was added. To this, methyl ethyl ketone (150.8 g) and toluene (77.7 g) were added and dissolved to obtain a solution.
The solution was aerated with nitrogen for 10 minutes to remove oxygen, and then heated at 60 ° C. for 16 hours with stirring.
Then, methyl ethyl ketone (320 g) was added to this solution, and then sodium hydroxide (12.5 g, 0.31 mol), butanol (463.1 g, 6.25 mol) and toluene (480 g) were added to the solution. Was added to the suspension and mixed at 45 ° C. for 3 hours. Then, this mixed solution was cooled to 40 ° C. and treated with formic acid (88% by mass aqueous solution, 49.0 g, 0.94 mol) to carry out proton addition.

Then, the washing step of adding methyl ethyl ketone (MEK) and water to this mixed solution to separate the aqueous layer was repeated until the alkali metal concentration in the alkali-soluble resin became 5 ppm or less. Then, methanol and hexane were added to separate the organic layer to remove unreacted monomers. Further, propylene glycol monomethyl ether acetate (PGMEA) was added, and methanol and butanol in the system were distilled off under reduced pressure until the residual amount was less than 1%. As a result, 1107.7 g of a polymer solution containing 40% by mass of a polymer having a chemical structure shown as Polymer 1 was obtained.
According to gel permeation chromatography (GPC) measurement, the weight average molecular weight Mw was 13,700 and the number average molecular weight Mn was 7,400.

<Preparation of resin composition>
Each component was uniformly stirred and mixed according to the formulation shown in Table 1 below, and then filtered through a filter having a pore size of 0.2 μm to prepare a resin composition.
Details of each component shown in Table 1 are as follows.

(polymer)
Polymer 1: Above PMMA: Known poly (methyl methacrylate)

(Crosslinking agent)
Epoxy 1: VG3101L (manufactured by Printec Co., Ltd., hereinafter structure)
Epoxy 2: EPICRON (registered trademark) HP-6000 (manufactured by DIC Corporation, containing naphthalene skeleton)
Phenoxy 1: jER® YX7105 (manufactured by Mitsubishi Chemical Corporation, weight average molecular weight 3000-4000)
Polycarbonate 1: PCP-100L2 (manufactured by Tosoh Corporation, trifunctional or higher functional polyol)

(UV absorber)
UV absorber 1: Uvinul (registered trademark) 3049 (manufactured by BASF Japan Ltd., hereinafter structure)
Ultraviolet absorber 2: Uvinul (registered trademark) 3050 (manufactured by BASF Japan Ltd., hereinafter structure)
UV absorber 3: RUVA-93 (manufactured by Otsuka Chemical Co., Ltd., hereinafter structure)
UV absorber 4: Anthracure (registered trademark) UVS-1331 (manufactured by Kawasaki Kasei Chemicals, Inc., hereinafter structure)

(Other ingredients)
Silane coupling agent: KBM-403E (manufactured by Shin-Etsu Chemical Co., Ltd., 3-glycidoxypropyltrimethoxysilane)
Fluorine-containing surfactant: Megafuck R-41 (manufactured by DIC Corporation)

<Measurement of light transmittance> (wavelength 355 nm, 633 nm)
It was measured by the following procedure.
(1) The resin composition was spin-coated on a silicon wafer. The rotation speed and the like were appropriately adjusted so that the film thickness after curing was 25 μm. It was then dried at 100 ° C. for 3 minutes and cooled to room temperature (23 ° C.). As a result, a resin film was formed on the silicon wafer.
The resulting resin film (2) (1), in an oven at an N ₂ atmosphere, 200 ° C., then heated for 90 minutes to obtain a cured film was subsequently allowed to cool to room temperature.
(3) The cured film obtained in (2) was immersed in a 1% by mass hydrofluoric acid aqueous solution together with the silicon wafer, and the cured film was peeled off from the wafer. Then, the hydrofluoric acid aqueous solution adhering to the cured film was thoroughly washed with water.
(4) The cured film peeled and washed with water in (3) was dried at 60 ° C. for 10 hours using an oven and cooled to room temperature (23 ° C.). Then, the cured film was cut into a size of 30 mm × 30 mm. This was used as a sample for measuring the light transmittance.
(5) The measurement sample obtained in (4) was set in an ultraviolet-visible near-red spectrophotometer "JASCOV-670" manufactured by JASCO Corporation, and the transmittance in the wavelength range of 190 to 1000 nm was measured. From this measurement result, the light transmittance (wavelength 355 nm, 633 nm) of the cured film having a film thickness of 25 μm was obtained.

<Evaluation of laser grooving suitability>
It was evaluated by the following procedure.
(1) A polyimide varnish (organic solvent solution of polyimide precursor, general-purpose product) was spin-coated on a silicon wafer, dried at 120 ° C. for 3 minutes, and cooled to room temperature. As a result, a resin film of the polyimide precursor was formed. The amount of coating and the number of rotations of the spin coat were appropriately adjusted so that the thickness of the cured polyimide film obtained in (2) below was 5 μm.
(2) Using an oven, the resin film of the polyimide precursor was heated together with the silicon wafer at 320 ° C. for 30 minutes. In this way, a silicon wafer on which a cured polyimide film (thickness 5 μm) was formed was obtained.
(3) A cured film (sacrificial layer) was provided on the cured polyimide film of (2) above as in (1) and (2) of <Measurement of light transmittance>.
(4) The cured film (sacrificial layer) of the above (3) is laser-grooved under the following conditions using the apparatus "MWL-WS05T" manufactured by Fine Device Co., Ltd. The film was burnt out. Then, the line formed by laser grooving was diced at a cutting speed of 10 mm / sec using an apparatus manufactured by DISCO (that is, a silicon wafer was cut).
(Laser grooving conditions)
Laser wavelength: 355 nm
Output: 0.8W
Repeat frequency: 10kHz
Processing speed: 500 mm / min

The cross section of the cut silicon wafer was observed with a scanning electron microscope (SEM) and evaluated in the following three stages.
〇 (Good): In the SEM observation of the cross section, there is no peeling between the sacrificial layer and the underlying PI layer.
Δ (normal): In SEM observation of the cross section, peeling between the sacrificial layer and the base PI layer is observed, but the peeling range is 5 μm or less.
X (defective): In the SEM observation of the cross section of the dicing line after the laser grooving dicing, peeling between the sacrificial layer and the base PI layer was observed, and the peeling range was larger than 5 μm.

<Measurement of etching rate>
First, a cured film was provided on the silicon wafer as in (1) and (2) of the above <Measurement of light transmittance>.
The cured film was dry-etched for 2 minutes under the following equipment and conditions. Then, the etching rate was calculated from the amount of change in film thickness before and after this, based on the formula (film thickness of cured film-film thickness after plasma treatment) / (dry etching time) (unit: μm / min). An optical interference type film thickness meter VM-1030 manufactured by Olympus Corporation was used for measuring the film thickness.
-Equipment: ICP (Inductively Coupled Plasma) etching equipment manufactured by Samco, product number "RIE-200iP"
Etching conditions: O ₂ gas, output 900 W (ICP), 450 W (Bias), flow rate 550 sccm, pressure 4.0 Pa, temperature 23 ° C (room temperature), voltage 200 V, frequency 13.56 MHz

<Evaluation of heat resistance (measurement of glass transition temperature Tg)>
First, a measurement sample was obtained as described in (1) to (4) of the above <Measurement of light transmittance>. However, the rotation speed of the spin coat was adjusted so that the film thickness of the cured film was 10 μm. The size of the measurement sample was 20 mm × 4 mm.
The measurement sample was set in Hitachi High-Tech Science's thermomechanical analyzer TMA-6000. Then, while applying a tensile load of 30 mN to the sample, the temperature was raised from 10 ° C. to 400 ° C. at a heating rate of 5 ° C./min, and a graph of horizontal axis: temperature and vertical axis: elongation amount was drawn. The intersection of the straight line portion on the high temperature side and the extension line of the straight line portion on the low temperature side in this graph was defined as Tg.

<Evaluation of residue after etching>
A cured film was obtained by the same procedure as in (1) and (2) of <Measurement of Light Transmittance> except that the silicon wafer was changed to a Cu wafer.
The cured film was dry-etched under the same equipment and conditions as in <Measurement of etching rate>. However, the time was set to the time calculated by (film thickness / etching rate) × 1.5, and all the cured film was removed.

Then, the area of the Cu wafer surface with an area of 314 cm and ² minutes was observed under a microscope. As a microscope, VHX-5000 (Keyence) was used.
When a residue was found by microscopic observation, it was analyzed by energy dispersive X-ray analysis (EDX analysis) whether the residue was derived from Si (whether it was derived from a silicon compound). Then, it was evaluated in the following three stages.
〇 (Good): Si-derived residue area is 0% of the total area
Δ (possible): Si-derived residue area is 0.01 to 3% of the total area
× (impossible): Si-derived residue area exceeds 3% of the total area

<Evaluation of curing shrinkage rate>
A cured film was provided on the silicon wafer as in (1) and (2) of the above <Measurement of light transmittance>. At this time, the film thickness before and after curing was measured, and the curing shrinkage rate (%) was calculated from the following formula. For the measurement of the film thickness, an optical interference type film thickness system VM-1030 manufactured by Olympus Corporation was used.
Formula: {(Thickness of resin film before curing-Thickness of cured film) / Thickness of resin film before curing} x 100

Table 1 summarizes the component compositions and evaluation results of the resin composition.

As shown in Table 1, the laser grooving suitability of the resin compositions of Examples 1 to 8 containing the ultraviolet absorber was good.
The etching rate of the cured film of the resin composition of Examples 1 to 8 was 2.5 μm / min or more. It can be said that the resin compositions of Examples 1 to 8 have excellent removability as a resin composition for forming a sacrificial layer.
On the other hand, the laser grooving suitability of the resin compositions of Comparative Examples 1 and 2 containing no ultraviolet absorber was poor.

A more detailed analysis of the examples shows that the evaluations of Examples 1 to 4 and 8 using epoxy 1 which is a trifunctional epoxy compound as a cross-linking agent and Example 6 using phenoxy 1 which is a phenoxy resin as a cross-linking agent , The heat resistance tended to be better.
Further, when the resin composition did not contain the silane coupling agent, the residue after etching was smaller (comparison between Example 8 and other examples).

1 Substrate 3 Intermediate layer 5 Sacrificial layer 10 Laser light 11 Dicing blade

Claims (16)

A resin composition used to form a sacrificial layer in the manufacture of electronic devices.
A non-photosensitive resin composition containing a resin and an ultraviolet absorber. The resin composition according to claim 1.
The ultraviolet absorber is a resin composition containing an organic ultraviolet absorber. The resin composition according to claim 1 or 2.
The ultraviolet absorber is a resin composition containing one or more selected from the group consisting of benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and anthracene-based ultraviolet absorbers. The resin composition according to any one of claims 1 to 3.
A resin composition in which the ratio of the ultraviolet absorber to the total solid content of the resin composition is 0.1 to 30% by mass. The resin composition according to any one of claims 1 to 4.
The resin is a resin composition containing a polymer having a non-aromatic cyclic skeleton in the main chain. The resin composition according to claim 5.
The polymer is a resin composition containing a structural unit represented by the following general formula (NB).

In the general formula (NB),
R ¹ , R ² , R ³ and R ⁴ are independently hydrogen atoms or organic groups having 1 to 30 carbon atoms.
a ₁ is 0, 1 or 2. The resin composition according to claim 5 or 6.
The polymer is a resin composition containing a structural unit represented by the following formula (MA).

The resin composition according to any one of claims 1 to 7.
A resin composition further containing a cross-linking agent. The resin composition according to claim 8.
The cross-linking agent is a resin composition containing at least one compound selected from the group consisting of an epoxy compound, an oxetane compound and a polyol compound. The resin composition according to any one of claims 1 to 9.
A resin composition that does not contain a photosensitizer. The resin composition according to any one of claims 1 to 10.
A resin composition in which the amount of the silane coupling agent in the total solid content of the resin composition is 5% by mass or less. The resin composition according to any one of claims 1 to 11.
A resin composition having a cured film obtained by heating the resin composition at 200 ° C. for 90 minutes in a nitrogen atmosphere and having a light transmittance of 50% or less per 25 μm film thickness at a wavelength of 355 nm. The resin composition according to any one of claims 1 to 12.
A resin composition having a cured film obtained by heating the resin composition at 200 ° C. for 90 minutes in a nitrogen atmosphere and having a light transmittance of 80% or more at a wavelength of 633 nm per film thickness of 25 μm. A sacrificial film forming step of forming a sacrificial film on a substrate by the resin composition according to any one of claims 1 to 13.
A dry etching process for dry etching the sacrificial film and
Electronic device manufacturing method including. The electronic device manufacturing method according to claim 14.
Between the sacrificial film forming step and the dry etching step, a laser grooving step of performing laser grooving on the sacrificial film and a laser grooving step.
A dicing step of dicing the substrate between the laser grooving step and the dry etching step,
Electronic device manufacturing method including. The electronic device manufacturing method according to claim 14 or 15.
In the sacrificial film forming step, an electronic device manufacturing method for forming the sacrificial film on the polyimide film of a substrate having a polyimide film.

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