JP2011132430A - Adhesive for semiconductor chip bonding, non-electroconductive paste, and non-electroconductive film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive for semiconductor chip bonding which is excellent in storage stability and rapid curability, is high in transparency, and facilitates the recognition of an alignment mark at the time of semiconductor chip bonding, and to provide a non-electroconductive paste and a non-electroconductive film produced by using the adhesive for semiconductor chip bonding. <P>SOLUTION: There are rovided an adhesive for semiconductor chip bonding comprising an epoxy resin, a phenolic curing agent of a hydroxyl equivalent of 110 or higher and 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole and a non-electroconductive paste and a non-electroconductive film characterized by being produced by using the adhesive. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an adhesive for bonding a semiconductor chip that is excellent in storage stability and fast curability, has high transparency, and facilitates recognition of an alignment mark during semiconductor chip bonding. The present invention also relates to a non-conductive paste and a non-conductive film manufactured using the semiconductor chip bonding adhesive.

In manufacturing a semiconductor device, a bonding process is performed in which a semiconductor chip is bonded and fixed to a substrate or another semiconductor chip. Currently, adhesives, adhesive sheets, and the like are often used for bonding semiconductor chips.

For example, Patent Document 1 discloses that in a semiconductor device having a structure including a semiconductor chip, a flexible wiring board, and an insulating layer sandwiched between them, the minimum viscosity by the capillary rheometer method at the heat bonding temperature is 100. An adhesive film for an insulating layer of ˜2000 Pa · s is disclosed. In Patent Literature 1, the adhesive film for an insulating layer described in the literature is excellent in controlling the amount of leaching, that is, suppressing the adhesive flowing out to an electrode portion for outputting an electric signal provided on a semiconductor chip, and has heat resistance. Further, it is described that the circuit filling property is also excellent.

On the other hand, in recent years, miniaturization and high integration of semiconductor devices have progressed. For example, flip chips having a plurality of protrusions as electrodes on the surface, stacked chips in which a plurality of thinly ground semiconductor chips are stacked, and the like are also produced. . Furthermore, in order to efficiently produce such miniaturized and highly integrated semiconductor devices, the automation of the manufacturing process is also progressing more and more.

In recent automated bonding processes, a semiconductor chip is aligned by a camera recognizing an alignment mark placed on the semiconductor chip. At this time, since the alignment mark is recognized from above the adhesive applied on the semiconductor chip, the adhesive used at the time of bonding is required to have transparency enough for the camera to recognize the alignment mark. It is done.
However, with conventional adhesives, when transparency is improved, storage stability is a problem at the same time, and both transparency and storage stability are compatible, contributing to improvement in productivity of semiconductor devices. New adhesives that can be used are desired.

Japanese Patent Laid-Open No. 11-12545

An object of the present invention is to provide an adhesive for bonding a semiconductor chip that has excellent storage stability and fast curing property, is highly transparent, and facilitates recognition of an alignment mark during semiconductor chip bonding. . Another object of the present invention is to provide a non-conductive paste and a non-conductive film manufactured using the semiconductor chip bonding adhesive.

The present invention is an adhesive for bonding a semiconductor chip containing an epoxy resin, a phenolic curing agent having a hydroxyl equivalent weight of 110 or more, and 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole. .
The present invention is described in detail below.

In general, in order to improve transparency in an adhesive for bonding a semiconductor chip containing an epoxy resin as a curable compound, for example, it is conceivable to increase the solubility of a curing agent and a curing accelerator in the epoxy resin. However, if the curing agent and the curing accelerator are sufficiently dissolved in the epoxy resin, the curing reaction is likely to proceed even during storage, leading to a decrease in storage stability.
In response to this problem, the present inventors have disclosed a semiconductor containing an epoxy resin, a phenolic curing agent having a hydroxyl equivalent weight of 110 or more, and 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole. It has been found that an adhesive for chip bonding is excellent in storage stability and fast curing property, has high transparency, and facilitates recognition of alignment marks during semiconductor chip bonding, and has led to the completion of the present invention. .

The adhesive for semiconductor chip bonding of the present invention contains an epoxy resin.
The epoxy resin is not particularly limited. For example, bisphenol A type, bisphenol F type, bisphenol AD type, bisphenol S type and other bisphenol type epoxy resins, phenol novolak type, cresol novolak type and other novolak type epoxy resins, trisphenol methane Examples thereof include aromatic epoxy resins such as triglycidyl ether, biphenyl type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins, and modified products and hydrogenated products thereof. These epoxy resins may be used independently and 2 or more types may be used together.

The adhesive for bonding a semiconductor chip of the present invention may contain a polymer compound having a functional group capable of reacting with the epoxy resin (hereinafter also simply referred to as a polymer compound having a functional group capable of reacting).
By containing the polymer compound having a functional group capable of reacting, the obtained cured product of the adhesive for bonding a semiconductor chip has toughness and can exhibit excellent impact resistance.

The polymer compound having a reactive functional group is not particularly limited, and examples thereof include a polymer compound having an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, an epoxy group, and the like. Among these, a polymer compound having an epoxy group is preferable.
By containing the high molecular compound which has the said epoxy group, the hardened | cured material of the adhesive agent for semiconductor chip joining obtained expresses the outstanding toughness. That is, the obtained cured product of the semiconductor chip bonding adhesive has excellent mechanical strength, heat resistance and moisture resistance derived from the epoxy resin, and excellent toughness derived from the polymer compound having the epoxy group. By having both, high joint reliability and connection reliability can be expressed.

The polymer compound having an epoxy group is not particularly limited as long as it is a polymer compound having an epoxy group at the terminal and / or side chain (pendant position). For example, an epoxy group-containing acrylic rubber, an epoxy group-containing butadiene rubber, Examples thereof include bisphenol type high molecular weight epoxy resin, epoxy group-containing phenoxy resin, epoxy group-containing acrylic resin, epoxy group-containing urethane resin, and epoxy group-containing polyester resin. Among these, an epoxy group-containing acrylic resin is preferable because it contains a large amount of epoxy groups and the cured product of the obtained adhesive for bonding semiconductor chips can exhibit excellent mechanical strength, heat resistance, toughness, and the like. These polymer compounds having an epoxy group may be used alone or in combination of two or more.

When the polymer compound having an epoxy group, particularly an epoxy group-containing acrylic resin, is used as the polymer compound having a reactive functional group, the preferred lower limit of the weight average molecular weight of the polymer compound having an epoxy group is 10,000. It is. When the weight average molecular weight is less than 10,000, the film-forming property of the obtained adhesive for bonding a semiconductor chip becomes insufficient. For example, even if the adhesive for bonding a semiconductor chip is made into a film, the shape is maintained as a film. There are things you can't do.

When the polymer compound having an epoxy group, particularly an epoxy group-containing acrylic resin, is used as the polymer compound having a functional group capable of reacting, the preferred lower limit of the epoxy equivalent of the polymer compound having an epoxy group is 200, preferably The upper limit is 1000. When the epoxy equivalent is less than 200, a cured product of the obtained adhesive for bonding a semiconductor chip may be hard and brittle. When the epoxy equivalent exceeds 1000, the mechanical strength, heat resistance, and the like of the resulting cured product of the adhesive for bonding a semiconductor chip may be insufficient.

When the adhesive for bonding a semiconductor chip of the present invention contains the polymer compound having the reactive functional group, the content of the polymer compound having the reactive functional group is not particularly limited, but the epoxy resin 100 A preferred lower limit relative to parts by weight is 1 part by weight, and a preferred upper limit is 500 parts by weight. When the content of the polymer compound having a reactive functional group is less than 1 part by weight, the cured product of the obtained adhesive for bonding a semiconductor chip has insufficient toughness when strain due to heat occurs. Bonding reliability may be inferior. When content of the high molecular compound which has the said functional group which can react exceeds 500 weight part, the heat resistance of the hardened | cured material of the adhesive agent for semiconductor chip bonding obtained may fall.

The adhesive for bonding a semiconductor chip of the present invention contains a phenolic curing agent having a hydroxyl equivalent weight of 110 or more. When the phenolic curing agent having a hydroxyl group equivalent of less than 110 is contained, the obtained semiconductor chip bonding adhesive has low storage stability. The adhesive for bonding a semiconductor chip of the present invention preferably contains a phenolic curing agent having a hydroxyl equivalent weight of 115 or more.

The phenolic curing agent having a hydroxyl group equivalent of 110 or more is not particularly limited as long as the hydroxyl group equivalent is 110 or more. And dicyclopentadiene phenol novolac type resin.

The content of the phenolic curing agent having a hydroxyl equivalent weight of 110 or more is not particularly limited, but a preferred lower limit with respect to a total of 100 parts by weight of the epoxy resin and the polymer compound having a reactive functional group is preferably 5 parts by weight. The upper limit is 150 parts by weight. When the content of the phenolic curing agent having a hydroxyl group equivalent of 110 or more is less than 5 parts by weight, the obtained adhesive for bonding a semiconductor chip may not be sufficiently cured or the rapid curability may be reduced. is there. When the content of the phenolic curing agent having a hydroxyl group equivalent of 110 or more exceeds 150 parts by weight, the obtained adhesive for bonding a semiconductor chip may have reduced storage stability or reduced transparency. . The content of the phenolic curing agent having a hydroxyl group equivalent of 110 or more is more preferably 10 parts by weight with respect to a total of 100 parts by weight of the epoxy resin and the polymer compound having a reactive functional group.

The adhesive for bonding a semiconductor chip of the present invention contains 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole.
By using a phenolic curing agent having a hydroxyl equivalent weight of 110 or more and 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole in combination, the resulting adhesive for bonding a semiconductor chip is storage stable. It has excellent properties and fast curability, and the curing reaction does not proceed during storage, but the curing reaction proceeds promptly once heated. Therefore, when a semiconductor chip is bonded using such a semiconductor chip bonding adhesive, the heat curing time of the semiconductor chip bonding adhesive can be shortened, and the time required for manufacturing the semiconductor device (tact time) ) Can be greatly shortened. Moreover, when the semiconductor chip to be bonded is thin, an effect of suppressing the generation of warp can be obtained.

Furthermore, by using a phenolic curing agent having a hydroxyl equivalent weight of 110 or more and 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole in combination, an adhesive for bonding a semiconductor chip is obtained. When the semiconductor chip is bonded using such an adhesive for bonding a semiconductor chip, the alignment mark can be easily recognized by a camera, and the productivity of the semiconductor device can be improved.

Examples of commercial products of 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole include TBZ (manufactured by Shikoku Kasei Kogyo Co., Ltd.).

The content of 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole is not particularly limited, but is preferably based on a total of 100 parts by weight of the epoxy resin and the polymer compound having a reactive functional group. The lower limit is 0.1 parts by weight, and the preferred upper limit is 10 parts by weight. If the content of 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole is less than 0.1 parts by weight, the resulting adhesive for bonding a semiconductor chip may not be sufficiently cured, Curability may decrease. When the content of 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole exceeds 10 parts by weight, the resulting adhesive for bonding a semiconductor chip may have reduced storage stability or transparency. It may decrease. The content of 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole has a more preferable lower limit with respect to 100 parts by weight in total of the epoxy resin and the polymer compound having a reactive functional group. 2 parts by weight, more preferably 5 parts by weight, and still more preferably 1 part by weight.

The adhesive for bonding a semiconductor chip of the present invention may contain an inorganic filler as long as the effects of the present invention are not impaired.
By containing the inorganic filler, the linear expansion coefficient of the cured product of the obtained adhesive for bonding a semiconductor chip is lowered. Therefore, when bonding a semiconductor chip using such an adhesive for bonding a semiconductor chip, stress generated on the semiconductor chip, the substrate, etc. can be suppressed, and the semiconductor chip, the substrate, etc. can be peeled off or warped, soldered, etc. The crack etc. which arise in the conduction part of can be controlled.
The inorganic filler is not particularly limited, and examples thereof include silica such as fumed silica and colloidal silica, alumina, aluminum nitride, boron nitride, silicon nitride, glass beads, and glass frit.

When a particulate inorganic filler is used as the inorganic filler, the preferred lower limit of the average particle diameter is 0.1 nm, and the preferred upper limit is 30 μm. When the average particle size of the particulate inorganic filler is less than 0.1 nm, the thickening effect is high, and the fluidity of the resulting adhesive for bonding a semiconductor chip may be lowered. When the average particle size of the particulate inorganic filler exceeds 30 μm, the inorganic filler may be bitten between the electrodes when the semiconductor chip is bonded using the obtained semiconductor chip bonding adhesive.

When the adhesive for semiconductor chip bonding of the present invention contains the inorganic filler, the content of the inorganic filler is not particularly limited, but is the total of the epoxy resin and the polymer compound having a functional group capable of reacting. A preferred lower limit for 100 parts by weight is 5 parts by weight, and a preferred upper limit is 80 parts by weight. If the content of the inorganic filler is less than 5 parts by weight, the effect of adding the inorganic filler may be hardly obtained. If the content of the inorganic filler exceeds 80 parts by weight, the coefficient of linear expansion of the cured product of the resulting adhesive for bonding semiconductor chips will decrease, but at the same time the elastic modulus will increase, causing stress on the semiconductor chip, substrate, etc. May not be suppressed.
The content of the inorganic filler is more preferably 10 parts by weight, more preferably 60 parts by weight, and still more preferably the lower limit with respect to 100 parts by weight of the total of the epoxy resin and the polymer compound having a reactive functional group. Is 15 parts by weight, and a more preferable upper limit is 40 parts by weight.

The adhesive for bonding a semiconductor chip of the present invention may contain a diluent within a range that does not impair the effects of the present invention.
Although the said diluent is not specifically limited, The reactive diluent taken in by hardened | cured material at the time of heat-hardening of the adhesive for semiconductor chip joining is preferable. Of these, a reactive diluent having two or more functional groups in one molecule is more preferable in order not to deteriorate the adhesion reliability of the obtained adhesive for bonding a semiconductor chip.
Examples of the reactive diluent having two or more functional groups in one molecule include aliphatic epoxy, ethylene oxide modified epoxy, propylene oxide modified epoxy, cyclohexane epoxy, dicyclopentadiene epoxy, phenol epoxy and the like. Can be mentioned.

When the adhesive for semiconductor chip bonding of the present invention contains the diluent, the content of the diluent is not particularly limited, but a total of 100 weights of the epoxy resin and the polymer compound having a reactive functional group. The preferred lower limit for parts is 1 part by weight, and the preferred upper limit is 50 parts by weight. If the content of the diluent is less than 1 part by weight, the effect of adding the diluent may be hardly obtained. When the content of the diluent exceeds 50 parts by weight, the adhesive reliability of the obtained adhesive for bonding a semiconductor chip may be inferior or desired viscosity characteristics may not be obtained. The content of the diluent is more preferably 5 parts by weight and more preferably 20 parts by weight based on a total of 100 parts by weight of the epoxy resin and the polymer compound having a reactive functional group.

The adhesive for bonding a semiconductor chip of the present invention may contain a solvent, if necessary.
The solvent is not particularly limited, and examples thereof include aromatic hydrocarbons, chlorinated aromatic hydrocarbons, chlorinated aliphatic hydrocarbons, alcohols, esters, ethers, ketones, glycol ethers (cellosolves), and fats. Examples thereof include cyclic hydrocarbons and aliphatic hydrocarbons.

The adhesive for semiconductor chip bonding of the present invention may contain an inorganic ion exchanger, if necessary. Among the inorganic ion exchangers, examples of commercially available products include IXE series (manufactured by Toagosei Co., Ltd.). When the adhesive for bonding semiconductor chips of the present invention contains the inorganic ion exchanger, the content of the inorganic ion exchanger is not particularly limited, but the preferred lower limit in the adhesive for bonding semiconductor chips of the present invention is 1 weight. %, And a preferred upper limit is 10% by weight.

The semiconductor chip bonding adhesive of the present invention may contain additives such as an anti-bleeding agent and an adhesion-imparting agent such as an imidazole silane coupling agent, if necessary.

The method for producing the semiconductor chip bonding adhesive of the present invention is not particularly limited. For example, the epoxy resin, the phenolic curing agent having a hydroxyl equivalent weight of 110 or more, and 2,3-dihydro-1H-pyrrolo [1,2 -A] Adhesion for bonding a semiconductor chip by mixing and mixing a predetermined amount of benzimidazole, a polymer compound having the above-mentioned reactive functional group added as necessary, the above inorganic filler and other additives, etc. And a method for obtaining an agent.
The method of mixing is not particularly limited, and examples thereof include a method of mixing using a homodisper, a universal mixer, a Banbury mixer, a kneader, and the like.

The use of the adhesive for bonding a semiconductor chip of the present invention is not particularly limited. For example, in manufacturing a semiconductor device, the adhesive for bonding a semiconductor chip of the present invention is used to bond a semiconductor chip to a substrate or another semiconductor chip. be able to.
The adhesive for bonding a semiconductor chip of the present invention is excellent in storage stability and quick curing, and has high transparency. Therefore, when bonding a semiconductor chip using the adhesive for bonding a semiconductor chip of the present invention. The time (takt time) required for manufacturing the semiconductor device can be greatly reduced, and the alignment mark can be easily recognized by the camera, thereby improving the productivity of the semiconductor device.

Furthermore, a non-conductive paste (NCP) and a non-conductive film (NCF) are manufactured using the adhesive for bonding a semiconductor chip of the present invention, and the semiconductor chip is substrated using the non-conductive paste and the non-conductive film. Alternatively, it can be bonded to another semiconductor chip. Such a non-conductive paste and a non-conductive film are also one aspect of the present invention.
Since the non-conductive paste and non-conductive film of the present invention are produced using the adhesive for bonding a semiconductor chip of the present invention, the non-conductive paste and the non-conductive film are excellent in storage stability and fast curability and have high transparency. Therefore, when a semiconductor chip is bonded using the non-conductive paste and non-conductive film of the present invention, the time required for manufacturing the semiconductor device (tact time) can be greatly reduced and alignment by a camera can be performed. Mark recognition becomes easy, and the productivity of the semiconductor device can be improved.

Although the thickness of the nonelectroconductive film of this invention is not specifically limited, A preferable minimum is 2 micrometers and a preferable upper limit is 500 micrometers. If the thickness is less than 2 μm, a smooth film may not be obtained when foreign matter is mixed. When the thickness exceeds 500 μm, the transparency of the non-conductive film is lowered, and when bonding a semiconductor chip, it becomes difficult to recognize the alignment mark by the camera, or the solvent tends to remain, and at the time of bonding and heat curing Sometimes bubbles are generated.

The method for producing the nonconductive film of the present invention is not particularly limited, for example, an extrusion molding method using an extruder, a curable compound such as the epoxy resin is diluted with a solvent to prepare a curable composition solution, Examples thereof include a solvent casting method in which the solution is cast on a separator and then dried, a spin coating method in which the solution is directly applied to a wafer, and a method in which the solution is screen-printed.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive for semiconductor chip joining which is excellent in storage stability and quick-curing property, is highly transparent, and makes it easy to recognize alignment marks during semiconductor chip bonding can be provided. . Moreover, according to this invention, the nonelectroconductive paste and nonelectroconductive film manufactured using this adhesive agent for semiconductor chip joining can be provided.

The embodiments of the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

(Examples 1-5, Comparative Examples 1-4)
According to the composition of Table 1, the following materials were stirred and mixed using a homodisper to prepare a semiconductor chip bonding adhesive.

(Epoxy resin)
Bisphenol A type epoxy resin (trade name “1004AF”, manufactured by Japan Epoxy Resin Co., Ltd.)
Biphenyl type epoxy resin (trade name “YX-4000”, manufactured by Japan Epoxy Resin Co., Ltd.)

(Polymer compound having a functional group capable of reacting)
Glycidyl group-containing acrylic resin (trade name “G-2050M”, manufactured by NOF Corporation)

(Phenolic curing agent)
Cresol novolac type resin (hydroxyl equivalent 117, trade name “KA-1160”, manufactured by DIC)
BPA novolac resin (hydroxyl equivalent weight 118, trade name “VH-4150”, manufactured by DIC)
Biphenylphenol novolac resin (hydroxyl equivalent 229, trade name “GPH-103”, manufactured by Nippon Kayaku Co., Ltd.)
Phenol novolak type resin (hydroxyl equivalent 104, trade name “TD-2131”, manufactured by DIC)

(Acid anhydride curing agent)
Trialkyltetrahydrophthalic anhydride (trade name “YH-306”, manufactured by Japan Epoxy Resin Co., Ltd.)

(Curing accelerator)
2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole (trade name “TBZ”, manufactured by Shikoku Kasei Kogyo Co., Ltd.)
2,4-Diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct (solid imidazole, trade name “2MAOK”, manufactured by Shikoku Kasei Kogyo Co., Ltd.)

(Inorganic filler)
Silica filler (trade name “SE-4000”, manufactured by Admatechs)
Glass beads (trade name “UBS-0010E”, manufactured by Unitika Ltd.)

(Other)
Silane coupling agent (trade name “KBM-573”, manufactured by Shin-Etsu Chemical Co., Ltd.)
Thickener (Brand name "Leosil MT-10", manufactured by Tokuyama)

(Evaluation)
The following evaluation was performed about the adhesive agent for semiconductor chip bonding obtained by the Example and the comparative example. The results are shown in Table 1.

(1) About storage-stable semiconductor chip bonding adhesive, initial viscosity η at 23 ° C. using an E-type viscometer (trade name “VISCOMETER TV-22”, manufactured by TOKI SANGYO CO. LTD, rotor used: φ15 mm) ₀ (Pa · s) and viscosity η _t (Pa · s) after one week from the preparation were measured.
The case where the viscosity η _t did not reach twice the initial viscosity η ₀ was evaluated as “◯”, and the case where it reached 2 times as “×” was evaluated for storage stability.

(2) Measurement of gelation time About 0.1 mL of adhesive for bonding semiconductor chips was dropped on a hot plate, and the glass was heated on a hot plate set in advance at 120 ° C., 150 ° C. and 200 ° C. Was pressed from above. The time until the glass did not come off was measured as the gel time.

(3) Measurement of haze value The adhesive for bonding semiconductor chips was formed into a film having a thickness of 70 μm, and haze measurement was performed.
Transparency was evaluated by setting “h” when the haze value was less than 80, and “x” when the haze value was 80 or more. Note that the haze threshold was set to 80 because the alignment mark was recognized using an alignment recognition camera mounted on a flip chip bonder (“DB100” manufactured by Kasuya Kogyo Co., Ltd.). This is because it was a case.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive for semiconductor chip joining which is excellent in storage stability and quick-curing property, is highly transparent, and makes it easy to recognize alignment marks during semiconductor chip bonding can be provided. . Moreover, according to this invention, the nonelectroconductive paste and nonelectroconductive film manufactured using this adhesive agent for semiconductor chip joining can be provided.

Claims (3)

An adhesive for bonding a semiconductor chip, comprising an epoxy resin, a phenolic curing agent having a hydroxyl equivalent weight of 110 or more, and 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole. A non-conductive paste manufactured using the semiconductor chip bonding adhesive according to claim 1. A non-conductive film manufactured using the adhesive for bonding a semiconductor chip according to claim 1.