JP2018172529A - Semiconductor adhesion sheet and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor adhesive sheet capable of reducing a warp after reflow in a semiconductor device that mounts a semiconductor element that is more thinned and made larger in size in response to tendency toward smaller size, lighter weight and higher function of an electronic device.SOLUTION: A semiconductor device obtained by adhering a semiconductor element on a support substrate via three-layer structured semiconductor adhesive sheet 1 including a support substrate 2 having elastic modulus in the range of 100 to 250 GPa, and an adhesive layer 3 containing (A) a thermosetting resin containing a bismaleimide, (B) a curing agent, and (C) a filler provided on both sides of the support substrate 2, and the semiconductor adhesive sheet 1. Here, the support substrate 2 is preferably a gold foil having a thickness of 3 to 20 μm and the adhesive layer 3 is preferably formed from a resin composition containing 25 to 75 vol.% of silver particles.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor bonding sheet for fixing a semiconductor element to a supporting base material such as a metal lead frame, a ceramic substrate, or an organic substrate, and a semiconductor device using the bonding sheet.

  In a semiconductor device, a process of fixing a semiconductor element (hereinafter also referred to as a semiconductor chip) such as an LED, IC, LSI or the like to a predetermined portion on a metal lead frame, a ceramic substrate, or an organic substrate affects the reliability of the semiconductor device. This is one of the important steps. Conventionally, as this connection method, a method of using a paste-like resin composition in which a filler is dispersed in a resin as an adhesive is known.

  In response to the trend toward smaller and lighter electronic devices and higher functionality, semiconductor packages are becoming increasingly thinner, thinner and narrower, and semiconductor devices are becoming thinner and larger. The proportion of semiconductor elements in the package volume is increasing. For this reason, the influence of the stress strain of the semiconductor element cannot be ignored.

  On the other hand, Patent Document 1 discloses that a die bonding paste having excellent stress relaxation properties can be obtained by using an epoxy resin having a special chemical structure.

JP 2007-294712 A

  However, with respect to semiconductor elements that are thinner and larger in size, warpage after reflow becomes a problem in semiconductor devices that mount the semiconductor elements, and a semiconductor bonding material that can reduce this warpage is required.

  As a result of diligent study, the inventors of the present invention have a three-layer structure semiconductor bonding sheet having adhesive layers on both sides, and by making the elastic modulus of the support substrate disposed at the center within a predetermined range, The present invention was completed by finding that the warpage after reflow of a semiconductor device can be reduced.

  That is, the semiconductor adhesive sheet of the present invention comprises a support base having an elastic modulus in the range of 100 to 250 GPa and (A) a bismaleimide resin having at least an aliphatic hydrocarbon group provided on both sides of the support base. And (B) a curing agent, and (C) an adhesive layer containing a filler. Here, the supporting substrate is preferably a metal foil having a thickness of 3 to 20 μm, and the adhesive layer is preferably formed from a thermosetting resin composition containing 25 to 75% by volume of silver particles.

  The semiconductor device of the present invention is characterized in that a semiconductor element is bonded to a support substrate via the semiconductor bonding sheet of the present invention.

  According to the semiconductor bonding sheet of the present invention, it is possible to stably fix the object on the support substrate, and in particular, even when a semiconductor element or the like undergoes a reflow process in manufacturing a semiconductor device, the reflow process is performed. Later warping can be reduced.

  According to the semiconductor device of the present invention, since the semiconductor bonding sheet of the present invention is used, warpage after reflow is small, and the semiconductor element can be stably bonded onto the support substrate, so that the product reliability is high. .

It is sectional drawing which shows schematic structure of the sheet | seat for semiconductor adhesion which is one Embodiment of this invention. It is sectional drawing which shows schematic structure of the semiconductor device which is one Embodiment of this invention.

Hereinafter, the present invention will be described in detail with reference to an embodiment.
<Semiconductor bonding sheet>
As shown in FIG. 1, a semiconductor bonding sheet 1 according to an embodiment of the present invention includes a support base 2 having an elastic modulus in a range of 100 to 250 GPa and an adhesive provided on both sides of the support base 2. And an agent layer 3. Since the adhesive layer 3 is formed on both surfaces of the support substrate 2, the semiconductor bonding sheet 1 can bond an object to be bonded to an arbitrary location.

  Here, the semiconductor bonding sheet 1 is usually mounted on the support base material by contacting and fixing one side to the support base for fixing the semiconductor element and the other side to the semiconductor element. It can be a semiconductor device. At this time, the adhesive layer 3 can be appropriately selected according to a support base material, a semiconductor element, or the like to be bonded.

  The semiconductor bonding sheet 1 is suitable for bonding a semiconductor element and a supporting base material, and has a better warp reduction effect than that in the past, particularly when bonding a large semiconductor element.

<Supporting substrate>
In this embodiment, the support base material 2 is a support base material which can hold | maintain the adhesive bond layer 3 mentioned later stably, and is a base material which has the elasticity modulus used as the range of 100-250 GPa.

  Here, the supporting substrate 2 is not particularly limited as long as it has the above characteristics, and examples thereof include materials such as metals, ceramics, and resins. As for the thickness of this support base material 2, 3-20 micrometers is preferable.

  When the elastic modulus of the support base 2 is in the range of 100 to 250 GPa as described above, the workability is good and after reflow even if a large semiconductor element is mounted on a metal lead frame, ceramic substrate, or organic substrate. Can be suppressed.

  When this elastic modulus is less than 100 GPa, warpage is not sufficiently suppressed, and when the elastic modulus is greater than 250 GPa, workability and handleability are poor. Further, if the thickness is less than 3 μm, the workability is inferior and the warpage is not sufficiently suppressed, and if the thickness is more than 20 μm, the handleability is inferior.

  The elastic modulus in this specification means Young's modulus (Pa), which is defined by the relationship with the amount of strain with respect to the direction of tensile stress in one direction. For example, a sample conforming to JISZ2241 using a tensile tester. It can be calculated by obtaining the slope of the stress with respect to the strain amount in a region where the strain indicated by the standard line and the stress corresponding thereto show a linear relationship.

Examples of the material of the support base 2 that can be used in the present embodiment include those made of metal such as iron and iron alloy, aluminum and aluminum alloy, copper and copper alloy, and the like. More specifically, for example, iron-nickel alloys typified by Hastelloy, Permalloy, Invar alloy, Kovar, 42 alloy, 45 alloy, 50 alloy, etc., Clofer alloy, ZMG, SUS304, SUS400 series, etc. Cr ferritic alloys (including stainless steel), A2000 series to 7000 series, aluminum alloys typified by duralumin (A2024), super duralumin (A2017), nickel base alloys typified by mnemonic, inconel, etc. _{Cr-5Fe-1Y 2 O 3} ), Cr -based alloy typified by Mo-Fe-Cr alloy, a copper alloy represented by C1000 series ~C6000 series, titanium, tantalum, zirconium, molybdenum and tungsten.

<Adhesive layer>
The adhesive layer 3 used here is an adhesive layer formed from a resin composition containing (A) a thermosetting resin, (B) a curing agent, and (C) a filler. The adhesive layer 3 can be used for manufacturing a semiconductor device, and is formed from a known resin composition containing the above components.

  The (A) thermosetting resin used here is a thermosetting resin containing at least a bismaleimide resin having an aliphatic hydrocarbon group. Since the semiconductor bonding sheet of this embodiment is used for the purpose of bonding a semiconductor element to a supporting substrate, it is required that the moisture absorption resistance and heat resistance are good. From such a viewpoint, the maleimide resin Is used.

Among these, a bismaleimide resin having an aliphatic hydrocarbon group in the main chain is preferable because it has good moisture absorption resistance, heat resistance, and film properties. The bismaleimide resin having an aliphatic hydrocarbon group is configured such that a main chain connecting two maleimide groups has an aliphatic hydrocarbon group having 1 or more carbon atoms. Here, the aliphatic hydrocarbon group may be any of linear, branched, and cyclic forms. In this embodiment, the aliphatic hydrocarbon group has 6 or more carbon atoms. In other embodiments, the carbon number is 12 or more. In another embodiment, carbon number is 24 or more.
In addition, the aliphatic hydrocarbon group is preferably directly bonded to the maleimide group.
By containing such a bismaleimide resin, it is possible to obtain a semiconductor bonding sheet that is excellent in heat resistance and has a low stress and good heat-bonding strength after moisture absorption.

（式中、ｎは１〜１０の整数である。） Specific examples include an imide-extended bismaleimide compound (A1) represented by the following general formula (1).

(In the formula, n is an integer of 1 to 10.)

  As this bismaleimide compound (A1), for example, BMI-3000 (manufactured by Designer Molecules, trade name; molecular weight 3000), BMI-5000 (manufactured by Desiner Molecules, trade name: molecular weight 5000), Etc.

  This bismaleimide compound (A1) has a number average molecular weight in terms of polystyrene of from 500 to 5,000, preferably from 1,000 to 3,000. When the number average molecular weight is less than 500, the heat resistance is lowered, and when it exceeds 5000, the temporary sticking property at the time of manufacturing a semiconductor device tends to be lowered.

（式中、Ｑは炭素数６以上の２価の直鎖状、分枝鎖状又は環状の脂肪族炭化水素基を示し、Ｐは２価の原子又は有機基であって、Ｏ、ＣＯ、ＣＯＯ、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２、Ｓ、Ｓ_２、ＳＯ及びＳＯ_２から選ばれる２価の原子又は有機基を少なくとも１つ以上含む基であり、ｍは１〜１０の整数を表す。） Moreover, as another bismaleimide resin, the bismaleimide compound (A2) represented by following General formula (2) is mentioned.

(In the formula, Q represents a divalent linear, branched or cyclic aliphatic hydrocarbon group having 6 or more carbon atoms, P is a divalent atom or organic group, and O, CO, M is a group containing at least one divalent atom or organic group selected from COO, CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , S, S ₂ , SO and SO _2; Represents an integer of 1 to 10.)

Here, the group represented by Q preferably has 6 to 44 carbon atoms. Examples of the divalent atom represented by P include O and S. Examples of the divalent organic group include CO, COO, CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , S ₂ , Examples thereof include SO and SO _{2 and} organic groups containing at least one of these atoms or organic groups. Examples of the organic group including the above-described atom or organic group include those having a hydrocarbon group having 1 to 3 carbon atoms, a benzene ring, a cyclo ring, a urethane bond, etc. as a structure other than the above, and as P in that case Examples include groups represented by the following chemical formula.

Examples of the bismaleimide compound (A2) include BMI-1500 (manufactured by Designer Molecules, trade name: molecular weight 1500), BMI-1700 (manufactured by Desiner Molecules, trade name: molecular weight 1700), and the like. Can be mentioned.
This (A) component may be used individually by 1 type, and 2 or more types may be mixed and used for it.

  As the thermosetting resin (A) used here, other thermosetting resins such as cyanate resin, epoxy resin, radical polymerizable acrylic resin and maleimide resin may be used in combination with the maleimide resin. . The thermosetting resin used in combination is preferably an epoxy resin.

  Further, among the epoxy resins, (A3) an allylated epoxy resin which is a polymer of allylated bisphenol and epichlorohydrin is preferably used. This (A3) allylated epoxy resin is prepared by, for example, dissolving a polyhydric phenol compound in a solvent such as alcohols such as methanol, isopropanol or n-propanol, or ketones such as acetone or methyl ethyl ketone, and then sodium hydroxide or potassium hydroxide. After reacting with allyl halides such as allyl chloride and allyl bromide using a base such as polyhydric phenol compound allyl ether, sodium hydroxide as a catalyst in a mixture of allylated polyphenol compound and epihalohydrin It can be obtained by reacting at 20 to 120 ° C. for 0.5 to 10 hours while adding or gradually adding a solid of alkali metal hydroxide such as potassium hydroxide.

（式中、Ｒ^１〜Ｒ^８は、それぞれ独立に水素原子、置換又は無置換のアルキル基及び置換又は無置換のアリル基から選ばれる基であって、そのうちの少なくとも１つは置換又は無置換のアリル基であり、ＸはＳＯ、ＳＯ_２、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２、Ｏ、ＣＯ及びＣＯＯから選ばれる２価の原子又は有機基であり、ｋは０又は１である。）が好ましく用いられる。 Furthermore, in this embodiment, the polymer of allylated bisphenol and epichlorohydrin as the component (A3) is a compound represented by the following general formula (3):

Wherein R ^{1 to} R ⁸ are each independently a group selected from a hydrogen atom, a substituted or unsubstituted alkyl group and a substituted or unsubstituted allyl group, at least one of which is substituted or unsubstituted X is a divalent atom or organic group selected from SO, SO ₂ , CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , O, CO and COO, and k is 0 or 1) is preferably used.

  Thus, in this embodiment, it is preferable to use the component (A1) and / or the component (A2) and the specific resin component (A3) in combination. Here, the compounding amount of the component (A3) is preferably 5 to 50% by mass in the total mass of the component (A). If it is less than 5% by mass, there may be a problem in curability of the thermosetting resin composition, and if it exceeds 50% by mass, the film property, adhesiveness and water absorption may be inferior.

  On the other hand, the blending ratio of the component (A1) and the component (A2) used in this embodiment is preferably 50 to 95% by mass in the total mass of the component (A). Moreover, it is preferable that the ratio of [(A1) component content / (A2) content] in mass% is from 0/100 to 90/10.

What is necessary is just to select suitably the (B) hardening | curing agent used here according to resin to be used, and generally the hardening | curing agent used for the sheet | seat for semiconductor adhesion can be used. Examples of the curing agent (B) include imidazole curing agents, radical polymerization initiators, phenol curing agents, acid anhydride curing agents, amine curing agents, imidazoline curing agents, triazine curing agents, and phosphine curing agents. Examples thereof include a curing agent.
Especially, the combination of (B1) imidazole type hardening | curing agent and (B2) radical polymerization initiator is preferable, and it can aim at coexistence of temporary sticking property and curability by a laminator by this.

  Examples of the (B1) imidazole curing agent used in the present embodiment include 2-methylimidazole, 2-undecylimidazole, 1-decyl-2-phenylimidazole, 1-cyanomethyl-2-undecylimidazole, and 2,4. -Diamino-6- (2'-methylimidazolyl- (1 '))-ethyl-s-triazine isocyanuric acid contributor, 2-methylimidazole isocyanuric acid contributor, 2-phenyl-4-methyl-5-hydroxymethylimidazole 2,3-dihydro-1H-pyrrolo (1,2-a) benzimidazole and the like.

  The (B2) radical polymerization initiator used in the present embodiment is not particularly limited as long as it is a polymerization catalyst usually used for radical polymerization, but preferably a rapid heating test (1 g of sample is placed on an electric heating plate). The decomposition start temperature in the measurement test of the decomposition start temperature when the temperature is raised at 4 ° C./min) is 40 to 140 ° C. When the decomposition start temperature is less than 40 ° C, the storage stability of the adhesive thermosetting resin composition at room temperature becomes poor, and when it exceeds 140 ° C, the curing time may become extremely long. In addition, the temperature at the time of 1% mass reduction | decrease with respect to the mass before a sample is heated here is set as decomposition | disassembly start temperature.

  Specific examples of the radical polymerization catalyst satisfying this condition include 1,1-bis (t-butylperoxy) -2-methylcyclohexane, t-butylperoxyneodecanoate, dicumyl peroxide, and the like. It is done. These may be used alone or in combination of two or more in order to control curability.

  In addition, in order to improve the preservability of the thermosetting resin composition, it is possible to add various polymerization inhibitors in advance. Examples of such a polymerization inhibitor include hydroquinone, methylhydroquinone, dibutylhydroxytoluene (BHT) and the like.

  As for the compounding quantity of this (B) hardening | curing agent, 0.1-10 mass parts is preferable with respect to 100 mass parts of total mass of (A) component. If this amount exceeds 10 parts by mass, the change over time in the viscosity of the thermosetting resin composition may increase and workability may decrease, and if it is less than 0.1 parts by mass, the curability may be significantly reduced. There is.

  As the filler (C) used here, generally known fillers can be used as the filler used in the semiconductor bonding sheet. For example, an inorganic filler, an organic filler, etc. are mentioned. Here, as the inorganic filler, for example, metal powder such as gold powder, silver powder, copper powder, aluminum powder and nickel powder, and inorganic such as fused silica, crystalline silica, silicon nitride, alumina, aluminum nitride, calcium carbonate and talc Examples thereof include a powder and a metal-coated inorganic filler in which the surface of the inorganic powder is coated with a metal.

  As this (C) filler, for example, silver powder is particularly preferable for conductive applications. Silver powder is easy to obtain, easy to handle, has many types of shapes and particle sizes, has good conductivity, and has advantageous properties such as no change in conductivity even when heated. In addition, silica is particularly preferable for insulating applications. Silica is easily available and easy to handle.

The shape of the filler (C) is not particularly limited, and for example, a flake shape (scale shape), a dendritic shape, a spherical shape, or the like is used. Moreover, if it can use for the adhesive bond layer for semiconductor adhesion, the particle size will not be specifically limited, For example, a filler with an average particle diameter of 10 nm-10 micrometers can be used. The average particle size of the filler (C) is preferably 0.1 to 10 μm, and more preferably 0.5 to 10 μm. Here, the allowable maximum particle diameter is preferably about 10 μm. In the present specification, the average particle diameter is 50% cumulative value in the volume-based particle size distribution obtained with a laser diffraction type particle size distribution measuring apparatus (D _50).

  Moreover, 25-75 volume% is preferable and, as for the mixture ratio of this (C) filler, when a resin composition is 100 volume%, 50-75 volume% is more preferable. As the blending ratio of the filler increases, the elastic modulus of the adhesive layer increases, which is effective in reducing the warpage of the semiconductor device. If the blending ratio exceeds 75% by volume, the adhesive force may be reduced, and if it is less than 25% by volume, the thermal expansion coefficient of the adhesive sheet increases, and the warp of the semiconductor device may increase.

  In addition to the above, the resin composition that forms this adhesive layer includes coupling agents, diluents, curing accelerators, low stress agents such as rubber and silicone, Foaming agents, surfactants, colorants (pigments, dyes), various polymerization inhibitors, antioxidants, and other various additives can be blended as necessary.

  Each of these additives may be used alone or in combination of two or more.

  This resin composition can be manufactured by applying a known method. For example, after kneading the above components and various components to be blended as necessary, using a known kneader such as a pot mill, a ball mill, a bead mill, a roll mill, a homogenizer, a super mill, a lyca mill, at room temperature or under heating. It is obtained by diluting with a solvent if necessary.

<Semiconductor bonding sheet manufacturing method>
In the semiconductor bonding sheet 1 of the present embodiment, first, the resin composition for forming the adhesive layer 3 as described above is diluted with a solvent, and the viscosity thereof is adjusted to about 0.1 to 2 Pa · s. Next, the prepared resin composition is applied onto the prepared support substrate 2 by a known coating method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, or a gravure coating method. It can be produced by drying and semi-curing.

  When using a support film, a plastic film such as polyethylene, polypropylene, polyester, polycarbonate, polyarylate, polyacrylonitrile, etc., having a release agent layer on the surface is used. The thickness of this support film is usually 10 to 50 μm, preferably 25 to 38 μm, from the viewpoint of handling properties. In this case, after the adhesive layer 3 is once formed on the support film, the obtained adhesive layer 3 with a film is transferred to both surfaces of the support substrate 2 to obtain the semiconductor bonding sheet 1.

  Moreover, it is preferable to apply | coat the sheet | seat 1 for semiconductor adhesion obtained by the said method so that the thickness after drying of the adhesive bond layer 3 which consists of the said resin composition may be set to 3-20 micrometers. If the thickness after drying is less than 3 μm, scraping or filler detachment occurs, and if the thickness after drying is more than 20 μm, there is a risk of resin cracking.

  About 10-60 micrometers is preferable and, as for the thickness of the sheet | seat 1 for semiconductor adhesion obtained here, 10-30 micrometers is more preferable.

<Semiconductor device>
As shown in FIG. 2, the semiconductor device 10 of this embodiment is formed by bonding the semiconductor element 11 to a predetermined portion of the lead frame 12 via the cured product 1a of the semiconductor bonding sheet 1 as described above. The semiconductor bonding sheet 1 obtained as described above is manufactured by a known method of bonding the semiconductor element and the lead frame 12 via the semiconductor bonding sheet 1 when the semiconductor element 11 is bonded to the lead frame 12. it can.

  More specifically, for example, the semiconductor element 11 is mounted on a metal lead frame such as a copper frame or PPF (palladium pre-plating lead frame) as a supporting base via the semiconductor bonding sheet 1 of the present embodiment, After the semiconductor bonding sheet 1 is heated and cured, the electrode portion of the lead frame 12 and the electrode 13 on the semiconductor element 11 are connected by wire bonding 14, and then these are sealed using a sealing resin 15. Or it can manufacture by accommodating in a package. Examples of the bonding wire 14 include wires made of copper, gold, aluminum, gold alloy, aluminum-silicon, and the like. Moreover, the temperature at the time of hardening the sheet | seat 1 for semiconductor adhesion is 100-230 degreeC normally, Preferably, it is 100-200 degreeC, and 190 degrees C or less is especially preferable in the case of a copper lead frame. The heating time is preferably about 0.5 to 2 hours.

  Here, examples of the semiconductor element 11 include known semiconductor elements such as transistors, diodes, and light emitting elements.

  In the drawing, a metal lead frame is illustrated as a support base of the semiconductor element, but it is not particularly limited as long as it is a member that supports and fixes the semiconductor element. For example, the present invention can be applied to a circuit board such as an organic substrate or a ceramic substrate, a heat radiating member, or the like.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples at all.

Example 1
<Raw material of adhesive resin composition>
(A2) Component: Imido-expanded bismaleimide (manufactured by Designa Molecules, Inc., trade name: BMI-1500; number average molecular weight 1500) 80 parts by mass (A3) Component: diallyl bisphenol A diglycidyl ether type epoxy resin (Japan) Kayaku Co., Ltd., trade name: RE-810NM; epoxy equivalent 223, hydrolyzable chlorine 150 ppm (1N KOH-ethanol, dioxane solvent, reflux 30 minutes) 20 parts by mass (B1) component: 2-undecylimidazole (Shikoku) Made by Kasei Kogyo Co., Ltd., trade name: Curesol C11Z) 1 part by mass (B2) Component: Dicumyl peroxide (manufactured by NOF Corporation, trade name: Park Mill D) 1 part by mass (C) Ingredient: Silver powder AgC-212D, Fukuda Metal Foil Powder Industry Co., Ltd.) 250 parts by mass (D) Component: KBM-8 3 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name; thiol-based silane coupling agent) 2 parts by weight of component (E): FA-513M (Hitachi Chemical Co., Ltd., trade name) 43 parts by weight

<Support base material>
Support base material A: thickness 15 μm, material SUS304, manufactured by Takeuchi Metal Foil Co., Ltd. (elastic modulus 193 GPa)

<Sheet preparation method>
The ingredients (A) to (E), which are the raw materials for the adhesive resin composition, are sufficiently mixed and further kneaded with three rolls, then diluted with methyl ethyl ketone (MEK), and the viscosity is about 1 Pa · s. To obtain an adhesive resin composition A.
The obtained adhesive resin composition A was applied to both main surfaces of the supporting substrate A (SUS304) by a bar coating method so that the thickness was 10 μm ± 3 μm, respectively, and dried at 150 ° C. for 3 minutes, A semi-cured semiconductor bonding sheet was obtained.

(Example 2)
As a raw material of the adhesive resin composition, instead of the component (A2), the component (A1): an imide-expanded bismaleimide (manufactured by Designer Molecules, Inc., trade name: BMI-3000; number average molecular weight 3000) 80 Except having used the mass part, by the same operation as Example 1, adhesive composition B was obtained and the sheet for semiconductor adhesion was obtained.

(Example 3)
In the same manner as in Example 1 except that the support substrate B (thickness 15 μm, material 42 alloy, manufactured by Takeuchi Metal Foil Powder Industry Co., Ltd. (elastic modulus 147 GPa)) was used instead of the support substrate A, the semiconductor An adhesive sheet was obtained.

(Comparative Example 1)
Instead of the support substrate A, a support base C (thickness 12.5 μm, material Upilex-S (polyimide film), manufactured by Ube Industries (elasticity 9 GPa)) was used in the same manner as in Example 1, A semiconductor bonding sheet was obtained.
(Comparative Example 2)
A semiconductor bonding sheet was obtained in the same manner as in Example 2 except that the supporting substrate C was used instead of the supporting substrate A.
(Comparative Example 3)
As a raw material of the adhesive resin composition, 80 parts by mass of thermoplastic polyimide (manufactured by SABIC, trade name: Ultem) is used in place of the component (A2), and n-methylpyrrolidone (NMP) is used instead of MEK. Except for solvent dilution, an adhesive resin composition C was obtained by the same operation as in Example 1 to obtain a semiconductor bonding sheet.

<Evaluation method>
The characteristics of the semiconductor adhesive sheet obtained as described above were evaluated by the following tests. These results are summarized in Table 1.

[Heat bond strength]
A 6 mm × 6 mm silicon chip and the obtained semiconductor bonding sheet were temporarily attached by a laminator and mounted on a copper lead frame, and then the semiconductor bonding sheet was cured by heating at 170 ° C. for 60 minutes. After curing, the adhesive strength under a 260 ° C. environment in the vertical direction was measured using a tensile adhesive strength measuring device.

[Adhesive strength after moisture absorption]
A 6 mm × 6 mm silicon chip and the obtained semiconductor bonding sheet were temporarily attached by a laminator and mounted on a copper lead frame, and then the semiconductor bonding sheet was cured by heating at 170 ° C. for 60 minutes. After curing, moisture absorption treatment was performed at 85 ° C./85% relative humidity / 168 hours, and the adhesive strength in a 260 ° C. environment in the vertical direction was measured using a tensile adhesive strength measuring device.

[Warpage after reflow]
An 8 mm × 8 mm silicon chip and the obtained semiconductor bonding sheet were temporarily attached by a laminator, mounted on a copper lead frame, and then cured using an oven at 170 ° C. for 60 minutes (OV curing).

  Displacement in the height direction when heated from room temperature to 260 ° C and then cooled to room temperature according to JEITA ED-7306 of the Japan Electronics and Information Technology Industries Association using a shadow moire measuring device (Thermoire AXP: manufactured by Akrometrix) The maximum value of the displacement difference was measured as the warp after reflow.

[Solder reflow resistance]
An 8 mm × 8 mm silicon chip and the obtained semiconductor bonding sheet were temporarily attached by a laminator, mounted on a copper lead frame, and then cured using an oven at 170 ° C. for 60 minutes (OV curing). This was molded under the following conditions using an epoxy sealing material (trade name: KE-G3000D (K)) manufactured by Kyocera Corporation.

  The obtained package was subjected to moisture absorption treatment at 85 ° C. and relative humidity 60% for 168 hours, followed by IR reflow treatment (260 ° C., 10 seconds) three times, and the number of external cracks generated in the package was measured with a microscope (magnification: 15 times). In addition, the number of internal cracks in the package was observed with an ultrasonic microscope. The number of samples in which cracks occurred for five samples is shown.

Package: PBGA (30 x 30 x 1.7 mm thickness)
・ Chip size: 8mm × 8mm (surface aluminum wiring only)
Lead frame: Copper Molding of sealing material: 175 ° C, 1 minute Post mold cure: 175 ° C, 6 hours

  As is clear from Table 1, SUS304 having an elastic modulus of 193 GPa and 42 alloy having an elastic modulus of 147 GPa were used as a supporting substrate, and an adhesive layer made of a predetermined thermosetting resin composition was formed on both surfaces thereof. Examples 1 to 3, which are semiconductor devices in which a silicon chip and a copper lead frame are bonded via a sheet for use, are capable of obtaining a sufficient adhesive force, excellent in solder reflow resistance, and effective in suppressing warpage after reflow. I found out.

  Therefore, the resin sheet of the present invention is useful for semiconductor bonding applications. By using this, a highly reliable semiconductor device that is sufficiently bonded and fixed and suppressed in warping can be obtained.

  DESCRIPTION OF SYMBOLS 1 ... Sheet | seat for semiconductor bonding, 2 ... Support base material, 3 ... Adhesive layer, 10 ... Semiconductor device, 11 ... Semiconductor element, 12 ... Lead frame, 13 ... Electrode, 14 ... Bonding wire, 15 ... Sealing resin

Claims (8)

  A thermosetting resin comprising a support base having an elastic modulus in the range of 100 to 250 GPa and (A) a bismaleimide resin having at least an aliphatic hydrocarbon group provided on both sides of the support base; (B) a curing agent And (C) an adhesive layer containing a filler, and a semiconductor bonding sheet.   The sheet for semiconductor adhesion according to claim 1, wherein the support base is a metal foil having a thickness of 3 to 20 μm. The bismaleimide resin having an aliphatic hydrocarbon group is a bismaleimide compound (A1) represented by the following general formula (1):

(Wherein, n represents an integer of 1 to 10). 4. The semiconductor according to claim 1, wherein the bismaleimide resin having an aliphatic hydrocarbon group contains a bismaleimide compound (A2) represented by the following general formula (2). Adhesive sheet.

(In the formula, Q represents a divalent linear, branched or cyclic aliphatic hydrocarbon group having 6 or more carbon atoms, and P represents O, CO, COO, CH ₂ , C (CH ₃ ) _2. , C (CF ₃ ) ₂ , S, S ₂ , SO and SO ₂ or a divalent atom or an organic group, or an organic group containing at least one or more of these atoms or organic groups, m is 1 to Represents an integer of 10.)   The said (A) thermosetting resin contains an epoxy resin, The sheet | seat for semiconductor adhesion of any one of Claims 1-4 characterized by the above-mentioned.   The semiconductor adhesive sheet according to claim 1, wherein the resin composition forming the adhesive layer contains 25 to 75% by volume of silver particles as the filler.   The semiconductor adhesive sheet according to claim 1, wherein the adhesive layer has a thickness of 3 to 20 μm.   A semiconductor device, wherein a semiconductor element is bonded to a support base via the semiconductor bonding sheet according to claim 1.

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