TW201319197A - Die bonding agent - Google Patents

Abstract

An objective of this invention is to provide a die bonding agent, by which a semiconductor device with excellent reliability can be obtained by an easy way. The present invention relates to a die bonding agent, which includes (A) a solid epoxy resin, (B1) a dicyandiamide and (B2) a carboxylic acid dihydrazide with a melting point less than or equal to 170 DEG C, and the ratio of mole number of activated hydrogen included in (B2) is 0.08 to 0.35 with respect to the mole number of epoxy group included in (A).

Description

Grain bond

The present invention relates to a die bonding agent, a semiconductor device using the die bonding agent, and a method of manufacturing a semiconductor device.

In the manufacture of a semiconductor device, a die bonding agent is commonly used in a subsequent step of a semiconductor element such as an IC or an LSI and a substrate or a lead frame. Typically, in the next step, the die bonding agent 2 is applied to the substrate 1 and heated to form the semiconductor device 3 after the grain bonding agent B-stage (semi-hardening phase; B-stage). It is reheated and hardened until the C stage (final stage; C-stage). After that, the electrode portion of the semiconductor element and the circuit pattern of the substrate are connected by the wire 4 (wire bonding), and sealed with the sealant 5 to obtain the semiconductor device 6 (see FIG. 1). An epoxy resin system is proposed for the die bonding agent used in this method (for example, refer to Patent Document 1).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2004-168906

As described above, in the method of manufacturing a semiconductor device, after the semiconductor element is mounted, the die bonding agent is heated by heating to be cured until C-stage, and then wire bonding and sealing are performed. The present inventors have come to improve the productivity and energy efficiency of a semiconductor device. In the case where the conventional epoxy resin-based die bonding agent is used, it is known that the die bonding agent melts at the time of wire bonding and sealing, although it is attempted to perform wire bonding and sealing without C-stage. There is a problem that the semiconductor element is deviated from the substrate.

An object of the present invention is to provide a die bonding agent which can solve the above problems and which can provide a semiconductor device with excellent reliability by a simple method. Specifically, the subject is to provide a die bond which can be bonded and sealed in a B-staged state even without C-stage, and a semiconductor device having high reliability can be manufactured.

The inventors of the present invention conducted various investigations and found that the problem can be solved by using a specific hardener.

1. The present invention relates to a die bonding agent comprising (A) a solid epoxy resin, (B1) dicyandiamide, and (B2) a carboxylic acid diterpene having a melting point of 170 ° C or lower, wherein (B2) The ratio of the number of moles of active hydrogen contained to the number of moles of epoxy groups contained in (A) is from 0.08 to 0.35.

2. The present invention relates to a grain bonding agent, wherein (B2) is selected from the group consisting of 1,3-bis(decylcarboxyethyl)-5-isopropylhydantoin and 7,11-octadecene One or more kinds of dicarboxylic acid diterpenes in a group of diene-1,18-dicarbene.

3. The present invention relates to the grain bonding agent according to the invention 1 or 2, wherein the ratio of the molar number of the active hydrogen contained in (B1) to the molar number of the epoxy group contained in (A) It is from 0.9 to 1.8.

The present invention relates to the die bonding agent according to any one of claims 1 to 3, wherein (A) is a solid bisphenol A type epoxy resin.

The present invention relates to the die bonding agent according to any one of claims 1 to 4, which further comprises a glycol ester solvent.

6. The present invention relates to a semiconductor device produced by using the die bonding agent according to any one of Inventions 1 to 5.

7. The present invention relates to a method of fabricating a semiconductor device comprising the steps of: (1) applying a die attaching agent according to any one of claims 1 to 5 to a substrate; (2) Heating, a step of B-staged the grain bonding agent applied to the substrate; (3) a step of mounting a semiconductor element on the substrate in a manner of adjoining the B-staged grain bonding agent; and (4) a semiconductor element After the electrode portion is wire-bonded to the circuit pattern of the substrate, the sealing step is performed using a sealant.

According to the die bonding agent of the present invention, the semiconductor device can be excellent in reliability in a simple manner. In detail, according to the die bonding agent of the present invention, wire bonding and sealing can be performed in a B-stage state even without C-stage, and a semiconductor device having high reliability can be manufactured.

The grain bonding agent of the present invention contains (A) a solid epoxy resin. In the present specification, the solid epoxy resin refers to an epoxy resin having a solid shape at room temperature (25 ° C). Since a solid epoxy resin is used, a grain bonding agent is applied to a substrate or the like, and the state of B-staged by heating is tack-free at room temperature. This step is advantageous in terms of preservation and the like.

In the case of (A), a solid o-cresol novolak type epoxy resin, a phenol novolak type epoxy resin, a modified phenol type epoxy resin, a naphthalene type epoxy resin, and a dicyclopentadiene type may be exemplified. Epoxy resin, epoxy propyl amine epoxy resin, biphenyl epoxy resin, bisphenol A epoxy resin, biphenyl aralkyl epoxy resin, bisphenol F epoxy resin, hydrogenation double A phenol A type epoxy resin, an aliphatic type epoxy resin, a stilbene type epoxy resin, a bisphenol A novolak type epoxy resin, or the like. Among them, from the viewpoint of non-adhesiveness and adhesion at room temperature, a bisphenol A type epoxy resin and a bisphenol F type epoxy resin are preferable. (A) Those having a weight average molecular weight of 850 to 2,900, preferably 900 to 1,700 can be used. The solid bisphenol A type epoxy resin may, for example, be a weight average molecular weight of from 900 to 1,700. The weight average molecular weight is a value determined by gel permeation chromatography (GPC) using polystyrene as a standard.

(A) may be used alone or in combination of two or more.

In the crystal grain bonding agent of the present invention, (B1) dicyandiamide and (B2) bismuth carboxylic acid having a melting point of 170 ° C or less are used in combination as a curing agent. (B2) The temperature at which the hardener acts as a starting point is low, and its function is mainly as a hardener in the B-stage of the grain bonding agent. On the other hand, (B1) has a high temperature as a function of the start of the hardener, and its function is mainly as a hardener in the case of the main hardening. By combining (B1) and (B2) having such characteristics, it is possible to exert a sufficient and stable adhesive force in the B-staged state, and to avoid a shift between the substrate and the semiconductor element during wire bonding and sealing.

In the present specification, the carboxylic acid dioxime refers to a compound having two groups represented by the following formula: -C(=O)NHNH ₂ .

From the viewpoint of the adhesion in the B-staged state, the die bond of the present invention uses divalent carboxylic acid having a melting point of 170 ° C or less as (B2). The melting point of (B2) is preferably from 100 to 170 ° C, more preferably from 120 to 160 ° C.

In the case of (B2), 1,3-bis(decylcarboxyethyl)-5-isopropylhydantoin (melting point: 120 ° C), 7,11-octadecadiene-1, 18-two calories (melting point 160 ° C) and the like. From the viewpoint of preservation stability of the grain bonding agent, 7,11-octadecadiene-1,18-dikacaridine is preferred.

(B2) may be used alone or in combination of two or more.

From the viewpoint of high temperature adhesion strength after the B stage, the grain bonding agent of the present invention is such that the number of moles of active hydrogen contained in (B2) is relative to the number of moles of epoxy groups contained in (A) The ratio (B2) is used in an amount of 0.08 to 0.35 in terms of the molar ratio of the active hydrogen contained in (B2)/the number of moles of the epoxy group contained in (A). More preferably, it is 0.10 to 0.30, still more preferably 0.12 to 0.28, and particularly preferably 0.15 to 0.25. In the present specification, the number of moles of the active hydrogen contained in (B2) is four times that of the molar number (B2).

From the viewpoint of the bonding strength after the C stage, the grain bonding agent of the present invention is such that the molar number of the active hydrogen contained in (B1) is relative to the number of moles of the epoxy group contained in (A). (B1), preferably 0.9 to 1.5, more preferably, the molar amount of the active hydrogen contained in (B1)/the number of moles of the epoxy group contained in (A) is from 0.9 to 1.8. 1.0 to 1.4. In the present specification, the molar number of the active hydrogen contained in (B1) is four times that of the molar number (B1).

The grain bonding agent of the present invention can contain a liquid epoxy resin in a range that does not impair the effects of the present invention. In this specification, liquid epoxy resin refers to An epoxy resin exhibiting fluidity at room temperature (25 ° C). The liquid epoxy resin may, for example, be a bisphenol A epoxy resin, a bisphenol F epoxy resin, a naphthalene epoxy resin, an aminophenol type epoxy resin, or a hydrogenated bisphenol A type epoxy resin. , aliphatic epoxy resin, oxime modified epoxy resin, polyalkylene ether modified epoxy resin, epoxy resin with special soft skeleton, alicyclic epoxy resin, etc. The epoxy resin (for example, bisphenol A type epoxy resin) which is the same as that of the solid epoxy resin can be regarded as being in a state at 25 ° C (that is, it is solid at 25 ° C under normal pressure or liquid) State) and differentiated use. For example, as the solid epoxy resin, a softening point of 50 to 100 ° C can be used. The liquid epoxy resin is preferably 45 parts by mass or less, more preferably 38 parts by mass or less, based on 100 parts by mass of (A).

The grain bonding agent of the present invention can use a resin other than an epoxy resin (hereinafter also referred to as "other resin") within a range that does not impair the effects of the present invention. The other resin may be a thermosetting resin or a thermoplastic resin, and is preferably a solid shape at room temperature (25 ° C). Other resins may, for example, be a phenoxy resin, an acrylic resin, a maleimide resin, a silicon resin, a quinone imine resin, a polyester resin, or a styrene copolymer. Wait. The other resin is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, based on 100 parts by mass of (A).

The die bond of the present invention can use a hardener of an epoxy resin other than (B1) and (B2) within a range not impairing the effects of the present invention. Examples of such a curing agent include phenol resins, aromatic amines, imidazoles, and carboxylic acids.

The crystal grain bonding agent of the present invention may contain an elastomer (acrylonitrile-butadiene rubber, argon oxide elastomer powder, etc.) for the purpose of adjusting the elastic modulus or the like; A filler (silica, alumina, etc.) is contained for the purpose of adjusting the thermal modulus, the expansion ratio, the thermal conductivity, etc., and a coupling agent (a decane coupling agent or the like) is contained for the purpose of adjusting adhesion, etc.; For the purpose of cloth suitability, additives such as a shaker, an antifoaming agent, a coloring agent, and a leveling agent are contained. The grain bonding agent of the present invention may contain conductive particles.

The grain bonding agent of the present invention may contain a solvent from the viewpoint of coating workability. The solvent is preferably a solvent having high solubility in (A) and low solubility in (B1) and (B2). When (B1) and (B2) are dissolved in a solvent, the hardening of the B-stage is excessive, and the adhesion at the time of mounting and wire bonding of the semiconductor element causes a problem. The solvent may, for example, be a glycol ester solvent, and examples thereof include ceramide acetate (for example, ethylene glycol monoethyl ether acetate) and carbitol acetate (for example, ethyl carbene). Alcohol acetate, butyl carbitol acetate, etc.); from the viewpoint of handling properties, etc., preferably carbitol acetate, more preferably ethyl carbitol acetate, butyl carbene Alcohol acetate. The amount of the solvent can be appropriately adjusted from the viewpoint of workability, and it is preferably 40% by mass or less in the use of the grain bonding agent.

The grain bonding agent of the present invention can be produced by mixing (A), (B1) and (B2) with any additives and solvents. For example, (A) may be dissolved in a solvent by heating a stirrer or the like, and (B1), (B2), and any additives may be added to the solute of (A) at room temperature, and kneader may be used. It is produced by kneading a three-way roll or the like.

The grain bonding agent of the present invention can have a viscosity after production of 20 to 80 Pa‧s at room temperature (25 ° C). From the viewpoint of workability, the viscosity is preferably 30 to 70 Pa‧s. In this case, the viscosity is based on an E-type viscometer. The value was measured at 25 ° C at a number of revolutions of 5 rpm and a rotor (3 ° X 9.7 R). The grain bonding agent of the present invention is excellent in storage stability.

The semiconductor device 16 can be manufactured by using the die bonding agent of the present invention, and can include a manufacturing method of the following steps.

(1) a step of applying the die bond 12 of the present invention to the substrate 11; (2) a step of B-staged the die bond applied to the substrate by heating; (3) abutting a step of mounting the semiconductor element 13 on the substrate in the form of a B-staged grain bonding agent; and (4) a step of sealing the circuit pattern of the semiconductor element and the circuit pattern of the substrate after sealing using the sealing agent 15 In the step (4), the sealant is heat-hardened and sealed, and the grain bonding agent in the B-stage state is substantially hardened (refer to Fig. 2).

By using the die bonding agent of the present invention, wire bonding and sealing can be performed even after the semiconductor device is mounted and cured by heating until the C-stage is completed as in the conventional semiconductor device method. However, the die bonding agent of the present invention can also be used in a conventional method in which a semiconductor element is mounted and then cured by heating until C-stage, or in a method of manufacturing a semiconductor device which is not subjected to wire bonding or sealing.

The coating method of the die bonding agent is not particularly limited, and drawing/printing can be performed using a dispenser, a screen, or the like.

The heating temperature at the time of B-staged the grain bonding agent applied to the substrate is preferably 100 to 150 °C. As long as it is in this temperature range, it is possible to exhibit sufficient adhesion in the B-stage state. Heating temperature during B-stage Good system 120 to 150 ° C.

The mounting method of the semiconductor element is not particularly limited and can be performed by a mounter or the like. The semiconductor component can be mounted as needed, for example, at 60 to 150 ° C, for example, a load of 10 to 100 N/chip.

The method of wire bonding the electrode portion of the semiconductor element and the circuit pattern of the substrate is not particularly limited, and may be performed by a wire bonder or the like.

After the wire bonding, in order to protect the member, a sealant may be used for sealing, but the method at this time is not particularly limited. As the sealant, a molding varnish which is well known in the art can be used, and examples thereof include an epoxy molding compound (EMC; Epoxy Molding Compound). The molding resin can usually be hardened by heating at 160 to 180 °C. When the grain bonding agent of the present invention has a B-stage state before sealing, it can be hardened by heating at this time, and the adhesion between the substrate and the semiconductor element is made stronger.

(Example)

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the invention is not limited to the examples.

The composition shown in Table 1 (the numerical values in the table are parts by mass), and the components were mixed to prepare a crystal grain bonding agent of the example/comparative example. The characteristics of each grain bonding agent were measured in the following manner.

[Save stability]

The grain bonding agent of the example/comparative example was measured using an E-type viscometer (product name TV-20, manufactured by Toki Sangyo Co., Ltd.) at 25 ° C, a number of revolutions of 5 rpm, and a rotor (3 ° X 9.7 R). Post-viscosity (initial viscosity) and after sealing The viscosity in the container after storage for a predetermined period of time (after the viscosity).

Calculate [{(post-time viscosity) (initial viscosity)}/(initial viscosity)]×100 (%) is less than 1 week and increases by 20% or more. When x is less than 2 weeks and is increased by 20% or more, it is ○3. When it is increased by more than 20% over the week, it is ◎

[sticky (tack)]

Using a printing machine (plate thickness: 50 μm), the die bonding agent of the example/comparative example was applied to a stainless steel substrate (40 mm × 60 mm) in a size of 30 mm × 50 mm, and then heated at 140 ° C for 60 minutes to carry out B-stage. Thereafter, the viscosity was measured at room temperature using a tack tester (Tack Tester) (product name: TAC-II, manufactured by RHESCA Co., Ltd.). It is preferably less than 10 gf.

Condition: down speed 1.0mm/sec pull-up speed 600mm/sec load 100gf time 1 second measurement distance 5mm probe diameter 5mm φ

[adhesiveness (die attach)]

The film was bonded in the same manner as the viscosity test (however, it was applied to a size of 5 mm × 5 mm), and a film of the grain-bonding agent of the Example/Comparative Example which was B-staged was prepared, and an adapter (manufactured by Panasonic Factory Solutions Co., Ltd.) was used. , product name FCB3), the wafer which has been heated at 140 ° C is mounted at a load of 2 kg / 5 mm ² for 0.5 seconds. Observation was carried out using an ultrasonic test equipment (product name: HiSpeed 1000TM, manufactured by Insight Co., Ltd.), and the wafer was ○ when it was mounted without voids, and was × when voids were generated.

The third (a) and third (b) drawings correspond to the second embodiment and the comparative example 6, respectively.

[Continuity (high temperature adhesion)]

The tantalum wafer was attached to the film of the grain-bonding agent of the B-staged Example/Comparative Example in the same manner as the adhesion (die adhesion). Thereafter, the substrate was heated at 180 ° C, and the bonding strength between the substrate and the tantalum wafer was measured using a tabletop strength tester (manufactured by DAGE Co., Ltd., product name Universal Bonder Series 4000).

[Adhesiveness (subsequent hardening followed by strength)]

The tantalum wafer was attached to the film of the grain-bonding agent of the B-staged Example/Comparative Example in the same manner as the adhesion (die adhesion). Thereafter, it was heated at 175 ° C for 60 minutes to perform main hardening. The adhesion strength between the substrate and the tantalum wafer was measured at room temperature using a tabletop strength tester (manufactured by DAGE Co., Ltd., product name Universal Bonder Series 4000).

Solid epoxy resin

Ep1: bisphenol A epoxy resin epoxy equivalent 475g / eq softening point 64 ° C Mw about 900 EP2: bisphenol A epoxy resin epoxy equivalent 650g / eq softening point 78 ° C Mw about 1200 Ep3: bisphenol A type Epoxy resin epoxy equivalent 925g/eq Softening point 97°C Mw approx. 1650 Ep4: aralkyl type epoxy resin containing biphenyl skeleton (NC3000, manufactured by Nippon Kayaku Co., Ltd.), epoxy equivalent 276g/eq Softening point 56°C Mw About 960

Liquid epoxy resin

Ep5: bisphenol A type epoxy resin epoxy equivalent 189g / eq Dicarboxylic acid diterpene DH1: 7,11-octadecadiene-1,18-dicarbene (melting point 160 ° C) DH2: 3-double ( Mercaptocarboxyethyl)-5-isopropylhydantoin (melting point 120 ° C) DH3: diammonium adipic acid (melting point 180 ° C) DH4: dodecanedioic acid dipoxide (melting point 190 ° C)

Phenolic novolac resin (H-4 made by Minghe Chemical Co., Ltd.)

The grain bonding agents of Examples 1 to 7 corresponding to the grain bonding agents of the present invention are non-viscous at room temperature after the B-stage, and are advantageous in terms of storage and the like. Further, the B-staged state shows good adhesion, and the germanium wafer can be mounted without voids. Further, in the B-staged state, the adhesion is excellent, and the high-temperature bonding strength is excellent. Furthermore, the adhesion after the formal hardening is also good. its Among them, Examples 2 to 7 using 7,11-octadecadiene-1,18-dicarbene were excellent in storage stability.

The grain bonding agent of Comparative Example 1 which lacked bismuth carboxylic acid had a high temperature bonding strength.

The grain bonding agents of Comparative Examples 2 and 3 using a bismuth carboxylic acid having a high melting point also had poor high-temperature bonding strength.

The grain bonding agent of Comparative Example 4 using a phenol novolak resin as a curing agent had a high temperature bonding strength and a difference in strength after the main curing, and the storage stability was also low.

Further, Comparative Example 5 in which the content of bismuth carboxylate was lower than the range of the present invention and Comparative Example 6 which was higher than the range of the present invention was inferior in terms of adhesion. Specifically, Comparative Example 5 was inferior in high-temperature strength, and Comparative Example 6 produced voids when the germanium wafer was mounted, and the strength at the high temperature was also poor.

(industrial availability)

According to the die bonding agent of the present invention, the semiconductor device can be excellent in reliability in a simple manner. In detail, even if it is not C-stage, it is possible to perform wire bonding and sealing in a B-stage state, and it is possible to manufacture a semiconductor device with high reliability, and it is industrially highly usable.

1, 11‧‧‧ substrate

2, 12‧‧‧ grain bonding agent

3, 13‧‧‧ semiconductor components

4, 14‧‧‧ wire

5, 15‧‧‧ Sealant

6‧‧‧Semiconductor device

Fig. 1 is a schematic view showing a conventional method of manufacturing a semiconductor device.

Fig. 2 is a schematic view showing a method of manufacturing a semiconductor device of the present invention.

Fig. 3 (a) and (b) show the results of the grain adhesion test of Example 2 and Comparative Example 6.

The first item of the patent application scope of the present application is a grain bonding agent. However, the drawing of the present invention is a schematic diagram of a manufacturing method of a semiconductor device or a photograph of an experimental result, and thus is not sufficient to represent the technical features of the present invention.

Claims (7)

A grain bonding agent comprising (A) a solid epoxy resin, (B1) dicyandiamide, and (B2) a dicarboxylic acid dihydrazide having a melting point of 170 ° C or less, wherein (B2) contains active hydrogen The ratio of the number of ears to the number of moles of the epoxy group contained in (A) is from 0.08 to 0.35. The grain bonding agent according to claim 1, wherein (B2) is selected from the group consisting of 1,3-bis(decylcarboxyethyl)-5-isopropylhydantoin and 7,11- One or more carboxylic acid diterpenes in a group of octadecadiene-1,18-dikason. The grain bonding agent according to claim 1 or 2, wherein the ratio of the number of moles of active hydrogen contained in (B1) to the number of moles of epoxy groups contained in (A) It is from 0.9 to 1.8. The grain bonding agent according to any one of claims 1 to 3, wherein (A) is a solid bisphenol A type epoxy resin. The die bonding agent according to any one of claims 1 to 4, wherein a diol ester solvent is further contained. A semiconductor device manufactured by using the die bonding agent according to any one of claims 1 to 5. A method of manufacturing a semiconductor device, comprising the steps of: (1) applying a die bond according to any one of claims 1 to 5 to a substrate; (2) heating by a step of B-staged the die bond applied to the substrate; (3) on the substrate in a manner adjacent to the B-staged grain bond a step of mounting a semiconductor element; and (4) a step of sealing the electrode pattern of the semiconductor element and the circuit pattern of the substrate, and then sealing with a sealant.