JP2012227442A - Semiconductor device manufacturing method and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device excellent in reliability.SOLUTION: A semiconductor device manufacturing method comprises the steps of: forming a thermally-degradable resin layer on a base material; fixing a silicon wafer on which a plurality of through plugs penetrating from a principal surface to a rear face are provided, and the base material via the thermally-degradable resin layer; providing first semiconductor elements electrically connected to the through plugs, respectively, on the rear face of the silicon wafer; forming an encapsulation material layer encapsulating the plurality of first semiconductor elements on the rear face of the silicon wafer by using a semiconductor encapsulating resin composition; and degrading the thermally-degradable resin layer by a heat treatment and isolating the base material from the silicon wafer to expose the principal surface of the silicon wafer.

Description

  The present invention relates to a semiconductor device manufacturing method and a semiconductor device.

  Patent Document 1 describes a packaging method for mounting a semiconductor chip on a mounting substrate having a through electrode. This packaging method includes the following steps. First, after forming a wiring hole in a silicon substrate, the wiring hole is filled with a conductive material to form a wiring. Next, a semiconductor chip is mounted by connecting to this wiring. Next, after a support plate such as a glass substrate is attached to the silicon substrate on the semiconductor chip mounting surface, the silicon substrate is thinned in the thickness direction from the surface opposite to the chip mounting surface (Patent Document). 1 claim 1). According to this document, since the thinning process of the silicon substrate is performed after the support substrate is attached to the silicon substrate, it is described that chipping and cracking of the silicon substrate can be suppressed during the manufacture of the package. .

JP 2005-166909 A

  As a result of the study by the present inventors, in the above technique, since the chip is mounted on the silicon substrate, the area of the silicon substrate per chip is limited. For this reason, it has been found that it is difficult to freely design the area ratio between the chip and the silicon substrate.

The present invention includes the following.
[1]
Forming a thermally decomposable resin layer on the substrate;
A substrate having a plurality of embedded conductive portions provided on a main surface thereof on the thermally decomposable resin layer; and a first semiconductor element electrically connected to the embedded conductive portion on the substrate. Arranging a plurality of structures and fixing the base material and the structures via the thermally decomposable resin layer;
Forming a sealing material layer that seals the plurality of structures on the thermally decomposable resin layer using a semiconductor sealing resin composition;
Decomposing the thermally decomposable resin layer by heat treatment, and separating the base material from the sealing material layer, thereby exposing the back surface of the substrate of the structure;
Grinding the back surface of the substrate to expose a buried conductive portion on the back surface to form a through plug.
[2]
The semiconductor device according to [1], wherein in the step of forming the sealing material layer, a temperature at which the semiconductor sealing resin composition is heated is lower than a temperature at which the thermally decomposable resin layer is thermally decomposed. Manufacturing method.
[3]
The method for manufacturing a semiconductor device according to [1] or [2], wherein the heat treatment is performed in a temperature range of 200 ° C. to 400 ° C.
[4]
The method for manufacturing a semiconductor device according to any one of [1] to [3], wherein a 5% weight reduction temperature of the thermally decomposable resin layer is 400 ° C. or lower.
[5]
[1] to [1], wherein the thermally decomposable resin layer includes at least one selected from the group consisting of a polycarbonate resin, a polyester resin, a polyamide resin, a polyimide resin, a polyether resin, and a polyurethane resin. 4] The method for manufacturing a semiconductor device according to any one of [4].
[6]
The method for manufacturing a semiconductor device according to any one of [1] to [5], wherein the thermally decomposable resin layer includes a photoacid generator.
[7]
The method for producing a semiconductor device according to [5], wherein the polycarbonate-based resin includes at least one structural unit selected from the group consisting of propylene carbonate, cyclohexylene carbonate, butylene carbonate, and norbornene carbonate.
[8]
In the step of fixing the base material and the structure, a plurality of first embedded conductive portions are provided on one surface of the first semiconductor element, and the first semiconductor element includes the first conductive element. The embedded conductive portion and the embedded conductive portion of the silicon wafer are electrically connected,
After the step of forming the encapsulant layer, the other surface of the first semiconductor element is ground together with the upper surface of the encapsulant layer, and the other surface of the first semiconductor element is filled with the first embedding layer. Exposing the embedded conductive portion to form a first through plug;
Providing a second semiconductor element electrically connected to the first through electrode on the other surface of the first semiconductor element;
Forming a sealing material layer for sealing the second semiconductor element provided on the other surface of the first semiconductor element, using the resin composition for semiconductor sealing. The method for manufacturing a semiconductor device according to any one of [1] to [7].
[9]
In the step of fixing the base material and the structure,
Providing the first semiconductor element on the substrate so as to be electrically connected to the embedded conductive portion;
The method according to any one of [1] to [8], including a step of arranging a plurality of the structures including the substrate and the first semiconductor element on the thermally decomposable resin layer. A method for manufacturing a semiconductor device.
[10]
A step of forming an insulating resin layer on one surface of the sealing material layer in which a plurality of the structures are embedded and the through plug is exposed;
The method of manufacturing a semiconductor device according to any one of [1] to [9], including a step of forming a wiring circuit on the insulating resin layer.
[11]
A semiconductor device obtained by the method for manufacturing a semiconductor device according to any one of [1] to [10].

  ADVANTAGE OF THE INVENTION According to this invention, the semiconductor device excellent in the freedom degree of design and its manufacturing method are provided.

It is sectional drawing and a top view which show the wafer level package in this Embodiment. It is sectional drawing which shows the laminated package in this Embodiment. It is process sectional drawing which shows the manufacture procedure of the semiconductor device in this Embodiment. It is process sectional drawing which shows the manufacture procedure of the semiconductor device in this Embodiment. It is process sectional drawing which shows the manufacture procedure of the semiconductor device in this Embodiment. It is process sectional drawing which shows the manufacture procedure of the semiconductor device in this Embodiment. FIG. 4 is a partial enlarged view of a process cross-sectional view illustrating the manufacturing procedure of the semiconductor device illustrated in FIG. It is process sectional drawing which shows the manufacturing procedure of the semiconductor device in the modification of this Embodiment. It is process sectional drawing which shows the manufacturing procedure of the semiconductor device in the modification of this Embodiment. It is sectional drawing which shows the wafer level package in the modification of this Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

The semiconductor device of this embodiment will be described.
FIG. 1 is a cross-sectional view and a top view schematically showing an example of the wafer level package 130 of the present embodiment. FIG. 1A is a cross-sectional view taken along the line AA ′ of FIG. FIG. 2 is a cross-sectional view schematically showing an example of the stacked package 100 of the present embodiment.

  As shown in FIG. 1A, the wafer level package 130 of this embodiment includes a pseudo wafer 111 and a wiring layer 129 provided on the pseudo wafer 111. The pseudo wafer 111 includes a thin layer silicon substrate 101, a through plug 105, a semiconductor chip 108, and a sealing material layer 110. The thin silicon substrate 101 is provided with a plurality of through plugs 105 penetrating from the main surface to the back surface. At least one semiconductor chip 108 is provided in the in-plane direction of the main surface of the thin silicon substrate 101 and is electrically connected to the through plug 105. The periphery of the semiconductor chip 108 and the silicon substrate 102 including the side walls and the upper surface thereof is sealed with a sealing material layer 110. In the pseudo wafer 111, a plurality of thin-layer silicon substrates 101 having a plurality of through plugs 105 are formed on one surface side in the in-plane direction.

  The wiring layer 129 includes a first insulating layer 112, a conductive layer 118, a conductor 122, a second insulating layer 124, and bumps 128. The bump 128 is electrically connected to the through plug 105 via the conductor 122 and the conductive layer 118. The conductive layer 118 is provided in the recessed portion of the first insulating layer 112. The periphery of the conductor 122 is covered with the first insulating layer 112 and the second insulating layer 124.

  As shown in FIG. 1B, a thin silicon substrate 101 is embedded in one surface of the sealing material layer 110 in the in-plane direction. One or more semiconductor chips 108 are arranged on each thin layer silicon substrate 101. The shape of the sealing material layer 110 is not particularly limited, but is preferably a circle, a rectangle, a square, or the like in plan view. Further, the shape of the thin silicon substrate 101 is not particularly limited, but is preferably rectangular or square in plan view, and a part thereof may be arcuate. The thin-layer silicon substrate 101 on which the semiconductor chip 108 is mounted is not particularly limited, but the number of arrangement in the vertical and horizontal directions may be the same or different in plan view, improving the density, securing the terminal area per unit semiconductor chip, etc. From these various viewpoints, they may be arranged point-symmetrically or in a lattice shape. The plurality of thin silicon substrates 101 and the semiconductor chip 108 are collectively covered with a sealing material layer 110 made of the same material.

  Further, in the in-plane direction of the sealing material layer 110, the thin-layer silicon substrate 101 is disposed at a vertical interval L1 and a horizontal interval L2 orthogonal to the vertical direction. For this reason, the number of the thin silicon substrates 101 can be freely designed on one surface of the sealing material layer 110. In other words, on one surface of the sealing material layer 110, the mounting area of the thin silicon substrate 101 can be freely increased or decreased as compared with the case of mounting on a silicon wafer whose mounting area is limited. Become. Therefore, in the present embodiment, the mounting area of the thin silicon substrate 101 can be freely designed with respect to the area of the semiconductor chip 108, so that a semiconductor device having excellent package flexibility can be obtained. Moreover, as one of the effects, the area for forming the wiring layer 129 can be increased by increasing the distance between L1 and L2. Thereby, the terminal area per thin layer silicon substrate 101 can be set to a desired area.

  As shown in FIG. 2, the stacked package 100 includes an interposer 132 and an electronic device 140 mounted on the interposer 132 via a wiring circuit 134. The electronic device 140 is obtained by dividing the wafer level package 130 into individual pieces. The electronic device 140 is electrically connected to the interposer 132 via the bump 128 and the wiring circuit 134.

  The interposer 132 is a substrate that supports the electronic device 140. The shape of the interposer 132 in plan view is not particularly limited, but is preferably a square shape such as a square or a rectangle. On the upper surface (one surface) of the interposer 132, for example, a wiring circuit 134 made of a conductive metal material such as copper is provided in a predetermined shape.

  In addition, as shown in FIG. 2, the thin silicon substrate 101 and the semiconductor chip 108 are electrically connected via a connection part 220 (not shown in FIG. 1) and are fixed by an adhesive layer 210. Is preferred. The periphery of the connection part 220 is covered with an adhesive layer 210. For example, the adhesive layer 210 is provided only directly below the semiconductor chip 108.

Next, a method for manufacturing the semiconductor device of the present embodiment will be described.
3 to 6 are process cross-sectional views illustrating an example of a manufacturing procedure of the semiconductor device.
The manufacturing method of the semiconductor device of the present embodiment preferably includes the following steps. First, the pseudo wafer 111 is formed. Next, a wiring layer is formed on the pseudo wafer 111 to obtain a wafer level package 130. The wafer level package 130 is separated into individual pieces to obtain an electronic device 140. By mounting the electronic device 140 on a mounting substrate, the stacked package 100 is obtained.
Hereinafter, each process is explained in full detail.

[Formation process of pseudo wafer 111]
The process of forming the pseudo wafer 111 includes the following processes. First, the thermally decomposable resin layer 20 is formed on the substrate 10. Subsequently, on the thermally decomposable resin layer 20, a substrate (silicon substrate 102) provided with a plurality of embedded conductive portions 106 on the main surface and electrically connected to the embedded conductive portions 106 on the silicon substrate 102. A plurality of structures including the first semiconductor element (semiconductor chip 108) to be arranged are arranged, and the base material 10 and the structure are fixed via the thermally decomposable resin layer 20. Then, the sealing material layer 110 which seals the some structure on the thermally decomposable resin layer 20 is formed using the resin composition for semiconductor sealing. Subsequently, the thermally decomposable resin layer 20 is decomposed by heat treatment, and the base material 10 is separated from the sealing material layer 110 to expose the back surface of the silicon substrate 102 of the structure. Thereafter, the back surface of the silicon substrate 102 is ground to expose the embedded conductive portion 106 on the back surface, thereby forming the through plug 105.
Hereinafter, details of the process of forming the pseudo wafer 111 will be described.

(Structure fixing process)
First, as shown in FIG. 3A, a plate-like silicon wafer 30 is prepared. Subsequently, a plurality of non-through holes 104 are formed in the main surface of the silicon wafer 30. The interval between the non-through holes 104 is not particularly limited, but is appropriately set according to the arrangement interval and chip size of the chips mounted on the silicon wafer 30 and the number of chip mounting IO (input / output) bumps per unit area. To do. The diameter of the non-through hole 104 is appropriately set according to the thickness of the substrate and a desired application, and can be determined according to the desired wiring, but can be, for example, about 10 μm to 50 μm. Further, the shape of the non-through hole 104 in the sectional view in the depth direction is not particularly limited, but an elliptical shape, a circular shape, a triangular shape, a rectangular shape, a polygonal shape, a forward tapered shape, a reverse tapered shape, and the like are preferable. For the formation of the non-through hole 104, various removal methods such as a chemical removal method and a physical removal method are used. Examples of the removal method include a dry etching method such as a deep-reactive ion etching (DRIE) method, a wet etching method using a chemical solution such as a potassium hydroxide (KOH) aqueous solution, a laser etching method, and a machining method using a micro drill. And photoexcited electrolytic polishing method. Further, the silicon wafer 30 may be covered with a protective layer before the non-through hole 104 is formed in the silicon wafer 30.

  Next, as shown in FIG. 3B, the embedded conductive portion 106 is formed by filling the non-through hole 104 with a conductive material. Thereby, a plurality of embedded conductive portions 106 are formed on the main surface of the silicon wafer 30. The conductive material constituting the embedded conductive portion 106 is not particularly limited, and examples thereof include copper (Cu), silver (Ag), nickel (Ni), tin (Sn), indium (In), and polysilicon. It is possible to use a metal material, or an alloy solder such as a gold-tin alloy, a tin-lead (Sn—Pb) alloy, tin (Sn), lead (Pb), gold (Au), indium (In), or aluminum (Al). it can. The composition of these alloys can be set appropriately. As a method for filling the non-through holes 104 with the conductive material, for example, a molten metal suction method, a plating method, a printing method, or the like can be used.

  Further, an insulating layer may be formed on the surface of the silicon wafer 30 and on the side wall and the bottom of the non-through hole 104, and the buried conductive portion 106 may be formed on the insulating layer. As this insulating layer, for example, other insulating materials such as silicon oxide, silicon nitride, and insulating resin can be used. A method for forming the insulating layer is not particularly limited, and a thermal oxidation method, a plasma CVD method, or the like can be used. Thereby, sufficient withstand voltage is obtained.

  As shown in FIG. 3C, a semiconductor element (semiconductor chip 108) is mounted on the silicon wafer 30. The semiconductor chip 108 and the embedded conductive portion 106 are electrically connected. As the semiconductor chip 108, various semiconductor chips such as logic and DRAM can be used. In addition to the semiconductor chip 108, a resistance element, a capacitor, or the like may be used as a semiconductor element disposed on the main surface of the silicon substrate 102. Thereafter, the silicon wafer 30 may be divided into individual semiconductor chips 108 or divided into a plurality of semiconductor chips 108. As a result, a plurality of structures having a predetermined ratio between the mounting area of the silicon substrate 102 and the area of the semiconductor chip 108 are obtained. Further, one or more semiconductor chips 108 may be mounted on the silicon substrate 102 after the silicon wafer 30 is divided into a plurality of parts.

  Here, a process of obtaining a structure in which the semiconductor chip 108 is mounted on the main surface of the silicon substrate 102 will be described in detail with reference to FIG. FIG. 7 is an enlarged view of a part of the process cross-sectional view showing the manufacturing procedure of the semiconductor device shown in FIG. The process of mounting the semiconductor chip 108 includes, for example, a first preparation process, a second preparation process, an adhesive layer formation process, an alignment process, and a bonding process. In the first preparation step, a silicon wafer 30 having a main surface with a through plug 105 having an electrode pad 208 mounted on the tip is prepared. In the second preparation step, the semiconductor chip 108 having the electrode pad 204 provided with the bump 206 at the tip is prepared. In the adhesive layer forming step, an adhesive layer 210 containing a flux active compound is disposed on at least one of the main surface of the silicon wafer 30 or the surface of the semiconductor chip 108 to cover the electrode pads 208 or the solder bumps 206 (FIG. 7 ( a)). In the alignment step, the silicon wafer 30 and the semiconductor chip 108 are pressed in a heated state with the electrode pad 208 and the solder bump 206 facing each other, and the silicon wafer 30 and the semiconductor chip 108 are bonded by the adhesive layer 210. At the same time, the electrode pads 208 and the solder bumps 206 are aligned (FIG. 7B). In the bonding step, the solder bumps 206 and the electrode pads 208 are metal-bonded by heating and melting the solder bumps 206 (FIG. 7C). Hereinafter, each mounting process will be described in detail.

  In the first preparation step, for example, it is preferable to form the electrode pad 208 on the through plug 105 of the silicon wafer 30. The electrode pad 208 preferably has a multilayer structure of two or more layers. Thereby, metal diffusion of the through plug 105 can be prevented. For example, the electrode pad 208 may be a metal thin film composed of three layers of Au / Ni / Cr, and a multilayer film in which the Cr layer is in contact with the embedded conductive portion 106 can be used. As the electrode pad 208, a metal thin film made of another material, a conductor layer formed by applying a paste, or the like can be used.

  Next, in the second preparation step, for example, it is preferable that a solder bump 206 is provided at the tip of the electrode pad 204 so as to cover a part or the whole thereof. The solder bump 206 is electrically connected to the electrode pad 208 in a one-to-one relationship. The electrode pad 204 is made of a metal material, and for example, is preferably made of the same metal as the electrode pad 208. Here, in the present embodiment, the solder bump 206 is provided on the electrode pad 204, but the solder bump 206 may be provided on the electrode pad 208, and the solder bump 206 is provided on the pads on both sides. It may be provided. The material constituting the solder bump 206 is the same as that of the bump 128 described later. The shape of the electrode pad 204 or the electrode pad 208 is not particularly limited, but may be a cone, a polygonal column, a polygonal pyramid, a bowl shape, or the like in addition to a cylindrical shape.

  Next, in the adhesive layer forming step, a paste-like adhesive layer composition containing a flux active compound is applied to the main surface of the silicon wafer 30 or the surface of the semiconductor chip 108, or the adhesive layer 210 formed into a film shape. Is preferably applied to the main surface of the silicon wafer 30 or the surface of the semiconductor chip 108 (FIG. 7A). The means for applying the paste adhesive layer composition is not particularly limited, and for example, a dispenser can be used. The amount of application is not particularly limited, and is, for example, an amount that covers the main surface of the silicon wafer 30 or the entire surface of the semiconductor chip 108. On the other hand, the adhesive layer 210 may be applied to substantially the entire surface of the semiconductor chip 108 so as to completely cover the solder bump 206. In order to obtain such a film-shaped adhesive layer 210, for example, a method of applying and drying a paste-like adhesive layer composition, a method of laminating a film-like adhesive layer composition, and the like can be mentioned. It is done.

  The composition for an adhesive layer according to the present embodiment includes, for example, a thermosetting resin and a compound having flux activity.

  As the thermosetting resin, for example, epoxy resin, oxetane resin, phenol resin, (meth) acrylate resin, unsaturated polyester resin, diallyl phthalate resin, maleimide resin and the like are used. Among them, an epoxy resin excellent in curability and storage stability, heat resistance, moisture resistance, and chemical resistance of a cured product is preferably used.

  As the epoxy resin, either an epoxy resin that is solid at room temperature or an epoxy resin that is liquid at room temperature may be used. Further, an epoxy resin that is solid at room temperature and an epoxy resin that is liquid at room temperature may be used in combination. Thereby, the design freedom of the melting behavior of the resin can be further increased.

  The epoxy resin solid at room temperature is not particularly limited. For example, bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, glycidylamine type epoxy resin, glycidyl ester Type epoxy resin, trifunctional epoxy resin, tetrafunctional epoxy resin and the like. More specifically, a solid trifunctional epoxy resin and a cresol novolac type epoxy resin may be included.

  The epoxy resin that is liquid at room temperature can be a bisphenol A type epoxy resin or a bisphenol F type epoxy resin. Moreover, you may use combining these.

  Although content of a thermosetting resin is not specifically limited, 25 to 75 weight% of the whole composition for contact bonding layers is preferable, and 45 to 70 weight% is especially preferable. When the content is within the above range, good curability can be obtained, and good melting behavior can be designed.

  The compound having the flux activity has a function of reducing the oxide film on the surface of the electrode terminal such as a solder bump that hinders the connection, and has a reducing power to remove the oxide film. The compound having flux activity is, for example, a compound having at least one carboxyl group and / or phenolic hydroxyl group in the molecule, and may be liquid or solid.

  Examples of the flux active compound containing a carboxyl group include an aliphatic acid anhydride, an alicyclic acid anhydride, an aromatic acid anhydride, an aliphatic carboxylic acid, and an aromatic carboxylic acid. Examples of the flux active compound having a phenolic hydroxyl group include phenols.

  Examples of the aliphatic acid anhydride include succinic anhydride, polyadipic acid anhydride, polyazeline acid anhydride and polysebacic acid anhydride.

  Examples of alicyclic acid anhydrides include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, and methylcyclohexene dicarboxylic acid. An anhydride etc. are mentioned.

  Examples of the aromatic acid anhydride include phthalic anhydride trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, glycerol tris trimellitate, and the like.

  Examples of the aliphatic carboxylic acid include a compound represented by the following formula (25).

  In addition, n in the above formula (25) is preferably 3 or more and 10 or less from the balance of flux activity, outgas at the time of adhesion, and elastic modulus after curing of the adhesive and glass transition temperature. By setting n to 3 or more, it is possible to suppress an increase in the elastic modulus after curing of the adhesive and to improve the adhesion to the adherend. Further, by setting n to 10 or less, it is possible to suppress a decrease in elastic modulus and further improve connection reliability.

Examples of the compound represented by the above formula (25) include n = 3 glutaric acid (HOOC— (CH ₂ ) ₃ —COOH), n = 4 adipic acid (HOOC— (CH ₂ ) ₄ —COOH), n = 5 pimelic acid (HOOC— (CH ₂ ) ₅ —COOH), n = 8 sebacic acid (HOOC— (CH ₂ ) ₈ —COOH) and n = ₁₀ HOOC— (CH ₂ ) ₁₀ —COOH— It is done.

  Other aliphatic carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid pivalate, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, acrylic acid, methacrylic acid, crotonic acid, Examples include oleic acid, fumaric acid, maleic acid, oxalic acid, malonic acid, and oxalic acid.

  Examples of aromatic carboxylic acids include benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, merophanic acid, platnic acid, pyromellitic acid, merit acid, triylic acid, xylic acid, Hemellitic acid, mesitylene acid, prenylic acid, toluic acid, cinnamic acid, salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6- Dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid), 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid, etc. Naphthoic acid derivatives; phenolphthaline; diphenolic acid and the like.

  Examples of the flux active compound having a phenolic hydroxyl group include phenol, o-cresol, 2,6-xylenol, p-cresol, m-cresol, o-ethylphenol, 2,4-xylenol, 2,5 xylenol, m- Ethylphenol, 2,3-xylenol, meditol, 3,5-xylenol, p-tertiarybutylphenol, catechol, p-tertiaryamylphenol, resorcinol, p-octylphenol, p-phenylphenol, bisphenol A, bisphenol F, bisphenol Monomers containing phenolic hydroxyl groups such as AF, biphenol, diallyl bisphenol F, diallyl bisphenol A, trisphenol, tetrakisphenol, phenol novolac resin, o-creso Novolac resins, bisphenol F novolac resin, bisphenol A novolac resins.

Since the flux active compound is three-dimensionally incorporated by reaction with a thermosetting resin such as an epoxy resin, at least two phenolic hydroxyl groups that can be added to the epoxy resin in one molecule, and a metal oxide film A compound having at least one carboxyl group directly bonded to an aromatic group exhibiting a flux action in one molecule is preferable. Examples of such compounds include 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6-dihydroxybenzoic acid, and 3,4-dihydroxybenzoic acid. Benzoic acid derivatives such as acid and gallic acid (3,4,5-trihydroxybenzoic acid); 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid, 3,7-dihydroxy- Naphthoic acid derivatives such as 2-naphthoic acid; phenolphthaline; and diphenolic acid.
These flux active compounds may be used alone or in combination of two or more.

  The content of the compound having the flux activity is not particularly limited, but from the viewpoint of improving the flux activity, it is preferably 1% by weight or more, particularly preferably 5% by weight or more of the entire composition for the adhesive layer. . If the thermosetting resin and the unreacted flux active compound remain, it causes migration. Therefore, in order not to leave a flux active compound that does not react with the thermosetting resin, the content of the flux active compound is not particularly limited, but may be 30% by weight or less of the total composition for the adhesive layer. Particularly preferred is 25% by weight or less. Within the above range, the oxide film on the surface of the copper foil is reduced, and a good bond with high strength can be obtained.

Although the composition for contact bonding layers is not specifically limited, It is preferable that the hardening | curing agent of a thermosetting resin is included.
Examples of the curing agent include phenols, amines, and thiols. When an epoxy resin is used as the thermosetting resin, good reactivity with the epoxy resin, low dimensional change during curing, and appropriate physical properties after curing (for example, heat resistance, moisture resistance, etc.) are obtained. Phenols are preferably used.

  Although it does not specifically limit as phenols, When the physical property after hardening of an adhesive agent is considered, bifunctional or more is preferable. Examples include bisphenol A, tetramethyl bisphenol A, diallyl bisphenol A, biphenol, bisphenol F, diallyl bisphenol F, trisphenol, tetrakisphenol, phenol novolacs, cresol novolacs, etc., but melt viscosity, reactivity with epoxy resin When considering the physical properties after curing, phenol novolacs and cresol novolacs can be preferably used.

  When phenol novolacs are used as the curing agent, the content is not particularly limited, but from the viewpoint of reliably curing the resin, it is preferably 5% by weight or more, particularly 10% by weight based on the total composition for the adhesive layer. The above is preferable. If epoxy resin and unreacted phenol novolac remain, it causes migration. Therefore, in order not to remain as a residue, it is preferably 30% by weight or less, particularly preferably 25% by weight or less, based on the entire composition for the adhesive layer.

  When the thermosetting resin is an epoxy resin, the content of the phenol novolac resin may be defined by an equivalent ratio with respect to the epoxy resin. Specifically, the equivalent ratio of the phenol novolac to the epoxy resin is not particularly limited, but is preferably 0.5 or more and 1.2 or less, particularly preferably 0.6 or more and 1.1 or less, and most preferably 0.7 Above, 0.98 or less is preferable. By setting the equivalent ratio of the phenol novolac resin to the epoxy resin to be equal to or higher than the above lower limit value, heat resistance and moisture resistance after curing can be secured, and by setting the equivalent ratio to be equal to or lower than the upper limit value, The amount of the epoxy resin and the unreacted residual phenol novolac resin can be reduced, and the migration resistance is improved.

  As another curing agent, for example, an imidazole compound having a melting point of 150 ° C. or higher can be used. If the melting point of the imidazole compound is too low, the adhesive resin may be cured before the solder powder moves to the electrode surface, resulting in unstable connection or reduced storage stability of the adhesive. Therefore, the melting point of imidazole is preferably 150 ° C. or higher. Examples of the imidazole compound having a melting point of 150 ° C. or higher include 2-phenylhydroxyimidazole and 2-phenyl-4-methylhydroxyimidazole. In addition, there is no restriction | limiting in particular in the upper limit of melting | fusing point of an imidazole compound, According to the adhesion temperature of an adhesive agent, it can set suitably.

When an imidazole compound is used as the curing agent, the content is not particularly limited, but is preferably 0.005% by weight or more and 10% by weight or less of the entire composition for the adhesive layer, and particularly 0.01% by weight. The content is preferably 5% by weight or less.
By making content of an imidazole compound more than the said lower limit, the function as a curing catalyst of a thermosetting resin can be exhibited more effectively, and the sclerosis | hardenability of an adhesive agent can be improved. Moreover, by setting the content of the imidazole compound to the upper limit value or less, the melt viscosity of the resin is not too high at the temperature at which the solder melts, and a good solder joint structure can be obtained. Moreover, the preservability of the adhesive can be further improved.
These curing agents may be used alone or in combination of two or more.

Although the composition for contact bonding layers is not specifically limited, It is preferable that film forming resin is included. Thereby, the film forming property to a film can be improved.
Examples of the film-forming resin include phenoxy resin, polyester resin, polyurethane resin, polyimide resin, siloxane-modified polyimide resin, polybutadiene, polypropylene, styrene-butadiene-styrene copolymer, styrene-ethylene-butylene-styrene copolymer, polyacetal. Resin, polyvinyl butyral resin, polyvinyl acetal resin, butyl rubber, chloroprene rubber, polyamide resin, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer, polyvinyl acetate, nylon, Acrylic rubber or the like can be used. These may be used alone or in combination of two or more.

  When a phenoxy resin is used as the film forming resin, its number average molecular weight is not particularly limited, but a phenoxy resin having a molecular weight of 5,000 to 15,000 is preferable. By using such a phenoxy resin, the fluidity of the adhesive before curing can be suppressed and the interlayer thickness can be made uniform. Examples of the skeleton of the phenoxy resin include, but are not limited to, bisphenol A type, bisphenol F type, and biphenyl skeleton type. Preferably, a phenoxy resin having a saturated water absorption rate of 1% or less is preferable because foaming, peeling, and the like can be suppressed even at high temperatures during bonding and solder mounting.

In addition, as a film-forming resin, a resin having a functional group such as a nitrile group, an epoxy group, a hydroxyl group, or a carboxyl group may be used for the purpose of improving adhesiveness or compatibility with other resins. As the resin, for example, an acrylic rubber having a functional group can be used.
When acrylic rubber (having a functional group) is used as the film-forming resin, it is possible to improve film formation stability when producing a film-like adhesive. In addition, since the elastic modulus of the adhesive can be reduced and the residual stress between the adherend and the adhesive can be reduced, the adhesion to the adherend can be improved.

  Although content of film forming resin is not specifically limited, It is preferable to set it as 5 to 45 weight% of the whole said resin composition. When the film-forming resin is blended within the above range, a decrease in film formability is suppressed and an increase in the elastic modulus after curing of the adhesive is suppressed. Can be improved. Moreover, the increase in the melt viscosity of an adhesive agent is suppressed by setting it as the said range.

  The composition for the adhesive layer is not particularly limited, but preferably contains a silane coupling agent. Thereby, the adhesiveness to the to-be-adhered thing of an adhesive agent can further be improved. Examples of the silane coupling agent include an epoxy silane coupling agent and an aromatic-containing aminosilane coupling agent. These may be used alone or in combination of two or more.

  Although content of a silane coupling agent is not specifically limited, 0.01 to 5 weight% of the whole composition for contact bonding layers is preferable, and 0.1 to 1 weight% is especially preferable. When the content is within the above range, the effect of improving the adhesion is particularly excellent.

  The composition for adhesive layers may contain components other than those described above. For example, various additives may be appropriately added in order to improve various properties such as resin compatibility, stability, and workability.

  A varnish obtained by dissolving such an adhesive layer composition in an aromatic hydrocarbon solvent such as toluene or xylene, an ester organic solvent such as ethyl acetate or butyl acetate, or a ketone organic solvent such as acetone or methyl ethyl ketone. Is applied to a polyester sheet and dried at a temperature at which the solvent evaporates to produce an adhesive sheet, thereby obtaining an adhesive layer 210 formed on the polyester sheet.

  Next, the solder bumps 206 of the semiconductor chip 108 and the electrode pads 208 of the silicon wafer 30 are mounted while being aligned so as to be in contact with each other (FIGS. 7B and 7C). This mounting is preferably performed by heating the semiconductor chip 108 and the silicon wafer 30 at the reflow temperature and pressing them together. At this time, since the periphery of the solder bump 206 is covered with the adhesive layer 210, the solder bump 206 and the electrode pad 204 can be solder-connected while removing the oxide film on the surface of the solder bump 206. Thereby, the semiconductor chip 108 and the silicon wafer 30 are electrically connected via the connection part 220.

  The bonding conditions are not particularly limited, but it is preferable to set the reflow temperature to + 10 ° C. to 100 ° C. of the melting point of the solder material and heat for 1 to 30 seconds. At this time, it is more preferable if heating is performed only from the semiconductor chip 108 side. This is because thermal stress on the silicon wafer 30 can be reduced, warpage caused by a difference in linear expansion coefficient from the chip can be reduced, and volatile voids can be suppressed.

  Next, the adhesive layer 210 is cured by heating. Thereby, since the periphery of the connection part 220 comprised from the electrode pad 204, the solder bump 206, and the electrode pad 208 can be sealed, connection reliability can be improved. Curing conditions can be appropriately selected depending on the composition for the adhesive layer to be used, and are not particularly limited. For example, 100 to 200 ° C is preferably 30 to 180 minutes, and 120 to 170 ° C is preferably 60 to 150 minutes. . For example, the curing temperature is equal to or higher than the glass transition temperature of the cured product of the adhesive layer composition.

  Although the glass transition temperature of the hardened | cured material of the composition for contact bonding layers is not specifically limited, For example, it is preferable that it is 20 to 300 degreeC, and it is especially preferable that it is 50 to 150 degreeC.

  As described above, by the mounting process shown in FIG. 7, the silicon wafer 30 and the semiconductor chip 108 can be bonded and fixed together while being electrically connected by the connecting portion 220. By adjusting the dicing position and the number and area of the semiconductor chips 108 per silicon wafer 30, a plurality of structures having different area ratios between the mounting area of the silicon substrate 102 and the area of the semiconductor chip 108 can be obtained. Further, a plurality of structures having the same area ratio may be obtained.

  Next, the base material 10 is prepared. The base material 10 preferably uses various areas and shapes according to the number and area of the silicon substrate 102 embedded in the sealing material layer 110, and is preferably a sacrificial material having flatness, rigidity and heat resistance. . The substrate 10 is not particularly limited, and examples thereof include a dummy substrate such as a silicon plate, a transparent substrate, a ceramic plate, a stainless plate, a copper plate, or a metal plate. Among these, a silicon wafer that is excellent in workability in a sealing material layer forming process and a wiring layer forming process, which will be described later, and convenience in which current facilities can be used is preferable. Moreover, although mentioned later in detail, when it is necessary to irradiate an active energy ray with respect to the thermally decomposable resin layer 20, it is preferable that the base material 10 is a transparent base material which permeate | transmits an active energy ray. .

  Next, a thermally decomposable resin layer 20 is formed on the substrate 10. A method of forming the thermally decomposable resin layer 20 is not particularly limited, but a method of forming a liquid thermally decomposable resin composition (varnish) by a spin coating method, a printing method, a dispensing method, Examples thereof include a method of laminating a film-like thermally decomposable resin composition. Among these, the spin coating method and the laminating method are preferable. Thereby, the film thickness of the thermally decomposable resin layer 20 can be made uniform.

  A method for forming a liquid thermally decomposable resin composition by spin coating, printing, or dispensing is not particularly limited, and the thermally decomposable resin composition that is liquid at room temperature or solid at room temperature. A varnish-like thermally decomposable resin composition obtained by dissolving a thermally decomposable resin composition in a solvent or diluent can be formed using a known spin coater, printing machine, or dispenser.

  The method of laminating the film-like thermally decomposable resin composition is not particularly limited, but the varnish-like thermally decomposable resin composition is made of a base film such as polyethylene, polypropylene, polyethylene terephthalate, etc. The film-like thermally decomposable resin composition can be produced by coating and drying the film, and then a film-like thermally decomposable resin composition can be formed by using a known laminator or the like.

  The thermally decomposable resin layer 20 is composed of a thermally decomposable resin composition. Here, the 5% weight reduction temperature of the thermally decomposable resin component contained in the thermally decomposable resin composition constituting the thermally decomposable resin layer 20 is preferably 400 ° C. or less, particularly preferably 350 ° C. or less. . By setting the 5% weight loss temperature in the above range, the thermal effect on the semiconductor chip 108 and the sealing material layer 110 can be reduced when the thermally decomposable resin layer 20 is thermally decomposed. For example, by setting the 5% weight loss temperature in the above range and adjusting the heating time, the thermally decomposable resin layer 20 can be thermally decomposed without heating exceeding 400 ° C.

  In order to set the 5% weight reduction temperature of the thermally decomposable resin component within the above temperature range, for example, a linear or branched thermally decomposable resin component having no alicyclic or aromatic skeleton is used. Just choose.

Further, the weight loss at the temperature at which the thermally decomposable resin component contained in the thermally decomposable resin composition constituting the thermally decomposable resin layer 20 is thermally decomposed is preferably 1% or more, particularly preferably 5% or more. Thereby, the residue of the thermally decomposable resin layer 20 adhering to the semiconductor chip 108 can be reduced. That is, by setting the weight reduction at the temperature for thermal decomposition within the above range, the heat-decomposable resin layer 20 can be thermally decomposed by adjusting the heating time.
Here, the weight loss at the temperature at which the thermally decomposable resin component is thermally decomposed is a value measured by TG / DTA (thermo weight / differential thermal analysis, atmosphere: nitrogen, heating rate: 5 ° C./min). .

  Further, the thermally decomposable resin component contained in the thermally decomposable resin composition constituting the thermally decomposable resin layer 20 has a 5% weight loss temperature of 50 ° C. or higher, particularly 100 ° C. or higher. Preferably it is a component. Thereby, it is possible to prevent the thermally decomposable resin layer 20 from being unnecessarily thermally decomposed during the process of forming the sealing material layer 110 and curing the sealing material layer 110.

  In order to set the 5% weight loss temperature to 50 ° C. or higher, for example, the molecular weight of the thermally decomposable resin component may be adjusted.

  Here, the 5% weight loss temperature means a temperature at which 5% weight is lost when measured by TG / DTA (thermogravimetric / differential thermal analysis). In the TG / DTA measurement, about 10 mg of a thermally decomposable resin component is precisely weighed and measured with a TG / DTA apparatus (manufactured by Seiko Instruments Inc.) (atmosphere: nitrogen, heating rate: 5 ° C./min).

  Furthermore, as described above, the heat decomposable resin component is thermally decomposed by heating, and in addition to the heat decomposable resin component of the type that volatilizes, the heat decomposable resin component is heated to lower the molecular weight. It is also possible to use a thermally decomposable resin component of the type in which the melt viscosity and softening temperature of the thermally decomposable resin component decrease.

Examples of the thermally decomposable resin component of the thermally decomposable resin composition constituting the thermally decomposable resin layer 20 include polycarbonate resins, polyester resins, polyamide resins, polyimide resins, polyether resins, Examples include polyurethane resins. Among these resin components, a polycarbonate resin that can effectively shorten the thermal decomposition time of the thermally decomposable resin layer 20 is preferable.
The thermally decomposable resin composition constituting the thermally decomposable resin layer 20 may be composed of only one type of resin, or may contain two or more types of resins. Further, the thermally decomposable resin layer 20 may contain a photoacid generator.

Here, the polycarbonate resin is a resin having at least a carbonate group (—O— (C═O) —O—) as a structural unit in the main chain, and may have other structural units.
The polyester-based resin is a resin having at least an ester group (— (C═O) —O—) as a structural unit in the main chain, and may have other structural units.
Further, the polyamide-based resin is a resin having an amide bond (—NH— (C═O) —) as a structural unit at least in the main chain, and may have another structural unit.
The polyimide resin is a resin having an imide bond (— (C═O) —NR— (C═O) —) as a structural unit in at least the main chain, and may have other structural units. Good. Here, R represents an organic group.
The polyether-based resin is a resin having an ether group (—O—) as a structural unit at least in the main chain, and may have another structural unit.
The polyurethane-based resin is a resin having at least a urethane bond (—O— (C═O) —NH—) as a structural unit in the main chain, and may have other structural units.

Moreover, as the thermally decomposable resin layer 20, a resin layer whose thermal decomposition temperature is lowered by irradiation with active energy rays is preferable. The thermally decomposable resin layer 20 is, for example, selected from the group consisting of a photoacid generator, a polycarbonate resin, a polyester resin, a polyamide resin, a polyimide resin, a polyurethane resin, and a (meth) acrylate resin. It is preferably composed of a thermally decomposable resin composition containing at least one kind of thermally decomposable resin component. By irradiating these thermally decomposable resin compositions with active energy rays in the presence of a photoacid generator, it becomes possible to form the thermally decomposable resin layer 20 whose thermal decomposition temperature is lowered.
Here, the active energy ray is a general term for electromagnetic waves including g-line (436 nm), h-line (405 nm), i-line (365 nm), X-rays, visible light, etc., or an electron beam. preferable.

Although it does not specifically limit as polycarbonate-type resin, For example, a polypropylene carbonate, a polyethylene carbonate, 1, 2- polybutylene carbonate, 1, 3- polybutylene carbonate, 1, 4- polybutylene carbonate, cis-2,3-poly Butylene carbonate, trans-2,3-polybutylene carbonate, α, β-polyisobutylene carbonate, α, γ-polyisobutylene carbonate, cis-1,2-polycyclobutylene carbonate, trans-1,2-polycyclobutylene carbonate Cis-1,3-polycyclobutylene carbonate, trans-1,3-polycyclobutylene carbonate, polyneopentyl carbonate, polyhexene carbonate, polycyclopropene carbonate, Licyclohexylene carbonate, poly (methylcyclohexene carbonate), poly (vinylcyclohexene carbonate), polydihydronaphthalene carbonate, polyhexahydrostyrene carbonate, polycyclohexanepropylene carbonate, polystyrene carbonate, poly (3-phenylpropylene carbonate), poly (3 -A trimethyl silyloxy propylene carbonate), a poly (3-methacryloyloxy propylene carbonate), a polyperfluoropropylene carbonate, and a polynorbornene carbonate, 1 type, or 2 or more types of combinations can be mentioned.
Among these, polypropylene carbonate, polycyclohexylene carbonate, polybutylene carbonate, polynorbornene carbonate, and polyneopentyl are particularly preferable because the thermal decomposition temperature can be lowered more effectively in the presence of a photoacid generator. Carbonate is preferred.

The polyester resin is not particularly limited. For example, terephthalic acid or dimethyl terephthalate is the main acid component, and at least one alkylene glycol selected from ethylene glycol, diethylene glycol, trimethylene glycol, and butylene glycol is the main glycol component. Polyester resin to be used. A part of the terephthalic acid component may be replaced with an aromatic, alicyclic or aliphatic bifunctional carboxylic acid component. Moreover, for example, polylactic acid obtained by polycondensation of lactic acid, which is a hydroxy acid having both a carboxylic acid component and an alcohol group component in the molecule, can also be mentioned.
Among these, polybutylene terephthalate and polylactic acid are particularly preferable because the thermal decomposition temperature can be effectively lowered by irradiation with active energy rays and the workability is excellent.

The polyamide-based resin is not particularly limited. For example, at least one dicarboxylic acid component selected from adipic acid, heptanedicarboxylic acid, octanedicarboxylic acid, nonanedicarboxylic acid, undecanedicarboxylic acid, and dodecanedicarboxylic acid, and tetramethylenediamine, Examples thereof include polyamide resins obtained by polycondensation reaction with at least one diamine component selected from hexamethylene diamine, octamethylene diamine, nonamethylene diamine, undecamethylene diamine, and dodecamethylene diamine. Moreover, for example, polyamide resins obtained by ring-opening polymerization of α-pyrrolidone, ε-caprolactam, ω-laurolactam, and ε-enantolactam which are lactams can also be mentioned.
Among these, 6,6-nylon is particularly preferable because the thermal decomposition temperature can be effectively lowered by irradiation with active energy rays and the workability is excellent.
Although it does not restrict | limit especially as a polyimide-type resin, For example, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'- diaminodiphenyl ether, 1, 4-bis (aminomethyl) cyclohexane, 1, 3 At least one diamine acid component selected from bis (aminomethyl) cyclohexane, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexanediamine; and 4,4 ′ -Hexafluoropropylidenebisphthalic dianhydride, 4,4'-biphthalic anhydride, diphenyl-2,3,3 ', 4'-tetracarboxylic dianhydride, diphenyl-2,2', 3 At least one tetracarboxylic dianhydride selected from 3′-tetracarboxylic dianhydride and pyromellitic dianhydride and heavy The polyimide resin obtained by addition reaction is mentioned.
Among these, poly (4,4′-oxydiphenylenepyromellitimide) is particularly effective because the thermal decomposition temperature can be effectively lowered by irradiation with active energy rays and the workability is excellent. preferable.

Although it does not restrict | limit especially as a polyurethane-type resin, For example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, 1,1,1-trimethylolpropane, 1,2,5-hexanetriol, 1,3- At least one polyol selected from polyhydric alcohols such as butanediol, 1,4-butanediol, 4,4′-dihydroxyphenylpropane, 4,4′-dihydroxyphenylmethane, pentaerythritol, and 2,4-tri Diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate And a polyurethane resin obtained by polyaddition reaction with at least one isocyanate selected from the above.
Among these, poly ((ethylene glycol) -alt- (4,4′-) is particularly preferable because the thermal decomposition temperature can be effectively lowered by irradiation with active energy rays and the workability is excellent. Phenylene) isocyanate) is preferred.

The (meth) acrylic resin is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) A copolymer of (meth) acrylic monomers selected from acrylic acid, 2-hydroxyethyl (meth) acrylate, and the like.
Among these, polymethyl methacrylate and polyethyl methacrylate are particularly preferred because the thermal decomposition temperature can be effectively lowered by irradiation with active energy rays and the workability is excellent.

  The weight average molecular weight (Mw) of the thermally decomposable resin component is preferably 1,000 to 1,000,000, and particularly preferably 5,000 to 800,000. By setting the weight average molecular weight to the above lower limit or more, it is possible to obtain the effect of improving the wettability with respect to the substrate 10 and the effect of improving the film forming property. Moreover, by setting it as the said upper limit or less, the effect of improving the compatibility with various components, the solubility with respect to various solvents, and also thermal decomposition property can be acquired.

  The thermally decomposable resin component is preferably blended in a proportion of 10% to 99% by weight of the total amount of the thermally decomposable resin composition (excluding the solvent and diluent). More preferably, it is blended at 20% by weight or more. By making content of a thermally decomposable resin component more than the said lower limit, while being able to prevent the thermally decomposable resin layer 20 remaining on the base material 10, a thick film can be formed on the base material 10. FIG.

The photoacid generator is not particularly limited, but tetrakis (pentafluorophenyl) borate-4-methylphenyl [4- (1-methylethyl) phenyl] iodonium (DPI-TPFPB), tris (4-t-butylphenyl) ) Sulfonium tetrakis- (pentafluorophenyl) borate (TTBPS-TPFPB), tris (4-t-butylphenyl) sulfonium hexafluorophosphate (TTBPS-HFP), triphenylsulfonium triflate (TPS-Tf), bis (4- tert-butylphenyl) iodonium triflate (DTBPI-Tf), triazine (TAZ-101), triphenylsulfonium hexafluoroantimonate (TPS-103), triphenylsulfonium bis (perfluoro Methanesulfonyl) imide (TPS-N1), di- (pt-butyl) phenyliodonium, bis (perfluoromethanesulfonyl) imide (DTBPI-N1), triphenylsulfonium, tris (perfluoromethanesulfonyl) methide (TPS) -C1), di- (pt-butylphenyl) iodonium tris (perfluoromethanesulfonyl) methide (DTBPI-C1), and combinations of two or more thereof.
Among these, tetrakis (pentafluorophenyl) borate-4-methylphenyl [4- (1-methylethyl) phenyl] is particularly preferred because the thermal decomposition temperature of the thermally decomposable resin component can be efficiently lowered. Iodonium (DPI-TPFPB) is preferred.

  The photoacid generator is preferably blended at a ratio of 0.01 wt% to 50 wt% of the total amount of the thermally decomposable resin composition (excluding the solvent and diluent). More preferably, it is blended at a ratio of 0.1 wt% to 30 wt%. By setting it to the above lower limit value or more, it becomes possible to stably lower the thermal decomposition temperature of the thermally decomposable resin component, and by setting the upper limit value or less, the heat decomposable resin layer 20 remains as a residue. Can be effectively prevented.

  As a combination of materials constituting the thermally decomposable resin layer 20, one or more of polypropylene carbonate, 1,4-polybutylene carbonate, or polyneopentyl carbonate and tetrakis (pentafluorophenyl) are particularly preferable. ) Borate-4-methylphenyl [4- (1-methylethyl) phenyl] iodonium (DPI-TPFPB).

  The polycarbonate resin forms a structure that facilitates thermal cleavage of the main chain of the polycarbonate resin in the presence of a photoacid generator, or forms a thermal ring-closing structure in which the polycarbonate resin itself is easily thermally decomposed. Therefore, it is considered that the thermal decomposition temperature can be lowered.

The following reaction formula (I) shows the mechanism of thermal cleavage of the main chain of the polypropylene carbonate resin and formation of a thermal ring closure structure.
First, H ⁺ derived from a photoacid generator protonates the carbonyl oxygen of the polypropylene carbonate resin, and further shifts the polar transition state to generate unstable tautomeric intermediates [A] and [B].
Then, in the case of the thermal cutting of the main chain, an intermediate [A] is fragmented as acetone and CO _2.
In the case of formation of a thermal ring closure structure (a or b), intermediate [B] produces propylene carbonate, which is fragmented as CO ₂ and propylene oxide.

また、熱分解性の樹脂組成物は、酸化防止剤を含んでいてもよい。酸化防止剤は、望ましくない酸の発生や、熱分解性の樹脂組成物の自然酸化を防止する機能を有している。

The thermally decomposable resin composition may contain an antioxidant. The antioxidant has a function of preventing generation of undesirable acid and natural oxidation of the thermally decomposable resin composition.

  Examples of the antioxidant include, but are not particularly limited to, for example, Ciba IRGANOX (registered trademark) 1076 and Ciba IRGAFOS (registered trademark) 168 available from Ciba Fine Chemicals of Tarrytown, New York. .

  Further, as other antioxidants, for example, Ciba Irganox 129, Ciba Irganox 1330, Ciba Irganox 1010, Ciba Cyanox (registered trademark) 1790, Ciba Irganox 3114, Ciba Ir31 and the like can be used.

  The content of the antioxidant is preferably 0.1 to 10 parts by weight, and more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the thermally decomposable resin component.

  In addition, the thermally decomposable resin composition may contain an acid scavenger, an acrylic, silicone, fluorine, vinyl or other leveling agent, an additive such as a silane coupling agent, or a diluent, if necessary.

The silane coupling agent is not particularly limited. For example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p -Styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxy Silane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltri Ethoxysilane 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxypropyl) Examples thereof include tetrasulfide and 3-isocyanatopropyltriethoxysilane, and these may be used alone or in combination of two or more.
When the thermally decomposable resin layer 20 contains a silane coupling agent, the adhesion with the silicon substrate 102 or the base material 10 can be improved.

As the thermally decomposable resin composition, those that do not decrease the thermal decomposition temperature even when irradiated with active energy rays may be used. For example, a norbornene-based resin may be contained.
Although it does not specifically limit as a norbornene-type resin, For example, what contains the structural unit shown by following General formula (21) can be mentioned.

In Formula (21), R ^{1 to} R ⁴ are each hydrogen, a linear or branched alkyl group having 1 to 20 carbon atoms, an aromatic group, an alicyclic group, a glycidyl ether group, the following substituent ( 22). Moreover, m is an integer of 0-4.

In Formula (22), R ⁵ is any one of hydrogen, a methyl group, and an ethyl group, and R ⁶ , R ^7, and R ⁸ are linear or branched alkyl groups having 1 to 20 carbon atoms, A linear or branched alkoxy group having 1 to 20 carbon atoms, a linear or branched alkylcarbonyloxy group having 1 to 20 carbon atoms, a linear or branched alkyl group having 1 to 20 carbon atoms, It is either a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms. N is an integer of 0-5.

The linear or branched alkyl group having 1 to 20 carbon atoms is not particularly limited, but is a methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group. , Nonyl group, decyl group and the like.
Among these, butyl group and decyl are excellent in compatibility with various components constituting the thermally decomposable resin layer 20, solubility in various solvents, and mechanical properties when the silicon substrate 102 and the base material 10 are fixed. Groups are preferred.

  The aromatic group is not particularly limited, and examples thereof include a phenyl group, a phenethyl group, and a naphthyl group. Among these, phenethyl is excellent in mechanical properties when the silicon substrate 102 and the base material 10 are fixed. Group and naphthyl group are preferred.

The alicyclic group is not particularly limited, but is a cyclohexyl group, norbornenyl group, dihydrodicyclopentadiethyl group, tetracyclododecyl group, methyltetracyclododecyl group, tetracyclododecadiethyl group, dimethyltetracyclododecyl group. And alicyclic groups such as trimer of ethyl group, ethyltetracyclododecyl group, ethylidenyltetracyclododecyl group, phenyltetracyclododecyl group, and cyclopentadiethyl group.
Among these, a cyclohexyl group and a norbornenyl group, which are excellent in mechanical properties when the silicon substrate 102 and the base material 10 are temporarily fixed, and further in thermal decomposability in the heating process, are preferable.

R ⁵ in the substituent (22) is not particularly limited as long as it is hydrogen, a methyl group or an ethyl group, but a hydrogen atom excellent in thermal decomposability in the heating step is preferable.

R ⁶ , R ⁷ and R ⁸ in the substituent (22) are each a linear or branched alkyl group having 1 to 20 carbon atoms, or a linear or branched alkoxy group having 1 to 20 carbon atoms. A linear or branched alkylcarbonyloxy group having 1 to 20 carbon atoms, a linear or branched alkylperoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms If it is either, it will not specifically limit.
Examples of such substituents include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, acetoxy group, propoxy group, butoxy group, methylperoxy group, isopropylperoxy group, t-butylperoxy group, phenoxy group. , A hydroxyphenoxy group, a naphthyloxy group, and the like. Among these, a methoxy group, an ethoxy group, and a propoxy group that are excellent in adhesion to the base material 10 and mechanical properties during processing of a semiconductor wafer are preferable.

  M in the general formula (21) is an integer of 0 to 4, and is not particularly limited, but 0 or 1 is preferable. When m is 0 or 1, the structural unit represented by the general formula (21) can be represented by the following general formula (23) or (24).

In the general formulas (23) and (24), R ^{1 to} R ⁴ are each hydrogen, a linear or branched alkyl group having 1 to 20 carbon atoms, an aromatic group, an alicyclic group, or a glycidyl ether. Group, and any one of the above substituents (22).

  In the general formulas (23) and (24), n in the substituent (22) is an integer of 0 to 5, and is not particularly limited, but n is preferably 0. When n is 0, the silyl group is directly bonded to the polycyclic ring via a silicon-carbon bond, and both the thermal decomposability of the thermally decomposable resin layer 20 and the mechanical properties during processing of the silicon wafer are compatible. can do.

The structural unit represented by the general formula (21) is not particularly limited, but norbornene, 5-methylnorbornene, 5-ethylnorbornene, 5-propylnorbornene, 5-butylnorbornene, 5-pentylnorbornene, 5 -Hexyl norbornene, 5-heptyl norbornene, 5-octyl norbornene, 5-nonyl norbornene, 5-decyl norbornene, 5-phenethyl norbornene, 5-triethoxysilyl norbornene, 5-trimethylsilyl norbornene, 5-trimethoxysilyl norbornene, 5 It can be obtained by polymerizing norbornene-based monomers such as methyldimethoxysisilylnorbornene, 5-dimethylmethoxynorbornene, and 5-glycidyloxymethylnorbornene.
When the norbornene monomer is polymerized, it may be polymerized with a single norbornene monomer or a plurality of norbornene monomers may be copolymerized. Among these norbornene-based monomers, 5-butylnorbornene, 5-decylnorbornene, 5-phenethylnorbornene, 5-triethoxysilylnorbornene, 5 which have excellent mechanical properties when the silicon substrate 102 and the base material 10 are fixed are used. -Glycidyloxymethyl norbornene is preferred.

  The norbornene-based resin is not particularly limited, and may be formed of a single structural unit represented by the general formula (21), or may be formed of a plurality of structural units.

More specifically, the norbornene-based resin is polynorbornene, polymethylnorbornene, polyethylnorbornene, polypropylnorbornene, polybutylnorbornene, polypentylnorbornene, polyhexylnorbornene, polyheptylnorbornene, polyoctylnorbornene, polynonylnorbornene. , Polydecylnorbornene, polyphenethylnorbornene, polytriethoxysilylnorbornene, polytrimethylsilylnorbornene, polytrimethoxysilylnorbornene, polymethyldimethoxysisilylnorbornene, polydimethylmethoxynorbornene, polyglycidyloxymethylnorbornene and other single polymers, norbornene- Triethoxysilyl norbornene copolymer, norbornene-glycidyloxymethyl norbo Nene copolymer, butylnorbornene-triethoxysilylnorbornene copolymer, decylnorbornene-triethoxysilylnorbornene copolymer, butylnorbornene-glycidyloxymethylnorbornene copolymer, decylnorbornene-glycidyloxymethylnorbornene copolymer, decyl Examples thereof include copolymers such as norbornene-butylnorbornene-phenethylnorbornene-glycidyloxymethylnorbornene copolymer, and polyglycidyloxymethylnorbornene-butylnorbornene-triethoxysilylnorbornene copolymer.
Among these, polybutylnorbornene, polydecylnorbornene, polytriethoxysilylnorbornene, polyglycidyloxymethylnorbornene-butylnorbornene-triethoxysilylnorbornene copolymer having excellent mechanical properties when the silicon substrate 102 and the base material 10 are fixed. Polymer, decylnorbornene-triethoxysilylnorbornene copolymer, butylnorbornene-glycidyloxymethylnorbornene copolymer, decylnorbornene-glycidyloxymethylnorbornene copolymer, decylnorbornene-butylnorbornene-phenethylnorbornene-glycidyloxymethylnorbornene copolymer Coalescence is preferred.

The norbornene-based resin preferably has a weight average molecular weight of 10,000 to 1,000,000, particularly preferably 30,000 to 800,000. By setting the weight average molecular weight within the above range, both the thermal decomposability of the thermally decomposable resin layer 20 and the heat resistance of the thermally decomposable resin layer 20 during silicon wafer processing can be achieved.
Here, the weight average molecular weight can be calculated as a polystyrene equivalent value by GPC (gel permeation chromatogram) using THF as a solvent.

  As a synthesis method of the norbornene resin having the structural unit represented by the general formula (21), for example, a catalyst containing a palladium ion source, a catalyst containing a nickel source, a catalyst containing platinum, a radical initiator, or the like is used. However, it is preferable to use a catalyst containing a nickel source that is excellent in reactivity during addition polymerization.

  The synthesis of the norbornene resin can be carried out in an organic solvent capable of dissolving the norbornene monomer. Examples of the organic solvent include, but are not limited to, aliphatic hydrocarbons such as pentane, hexane, heptane, octane, and decane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; benzene, chlorobenzene, and nitrobenzene. Aromatic hydrocarbons such as toluene and xylene; methylene chloride, chloroform, carbon tetrachloride, ethyl chloride, 1,1-dichloroethane, 1,2-dichloroethane, 1,2-dichloroethylene, 1-chloropropane, 2-chloropropane, 1 Mention may be made of halogenated (polar) hydrocarbons such as -chlorobutane, 2-chlorobutane, 1-chloro-2-methylpropane, 1-chloropentane.

  The molar ratio of the catalyst containing palladium to the norbornene-based monomer is preferably 20: 1 to 100,000: 1, particularly preferably 200: 1 to 20,000: 1, and 1,000: 1 to 10,000: 1. Is more preferable.

When the norbornene-based monomer is polymerized with a nickel catalyst, the polymerization temperature is preferably −100 ° C. to 120 ° C., particularly preferably −60 ° C. to 90 ° C., and further preferably −10 ° C. to 80 ° C.
The norbornene-based resin is preferably blended at a ratio of 10% by weight to 100% by weight of the total amount of the thermally decomposable resin composition (excluding the solvent and diluent). More preferably, it is blended at 20% by weight or more.

Moreover, the said varnish may contain the solvent and the diluent in addition to each component mentioned above.
Solvents are not particularly limited, but hydrocarbons such as mesitylene, decalin, mineral spirits, alcohols / ethers such as anisole, propylene glycol monomethyl ether, dipropylene glycol methyl ether, diethylene glycol monoethyl ether, diglyme, etc. , Esters / lactones such as ethylene carbonate, ethyl acetate, N-butyl acetate, ethyl lactate, ethyl 3-ethoxypropionate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene carbonate, γ-butyrolactone, cyclopenta Non-, cyclohexanone, methyl isobutyl ketone, ketones such as 2-heptanone, and amide / lactams such as N-methyl-2-pyrrolidinone When the varnish contains a solvent, it becomes easy to adjust the viscosity of the varnish, and it becomes easy to form a thin film of the thermally decomposable resin layer 20.

  Although content of a solvent is not specifically limited, It is preferable that it is 5-98 weight% of the whole quantity of a thermally decomposable resin composition, and it is especially preferable that it is 10-95 weight%.

Further, the diluent is not particularly limited, but examples thereof include cycloether compounds such as cyclohexene oxide and α-pinene oxide, and aromatic cyclohexane such as [methylenebis (4,1-phenyleneoxymethylene)] bisoxirane. Examples thereof include cycloaliphatic vinyl ether compounds such as ether and 1,4-cyclohexanedimethanol divinyl ether.
When the varnish contains a diluent, the fluidity of the varnish can be improved. Thereby, the wettability with respect to the base material 10 of the thermally decomposable resin layer 20 can be improved.

  Here, returning to FIG. 3D, the thermally decomposable resin layer 20 has adhesiveness, and a plurality of embedded conductive portions 106 are provided on the main surface on the thermally decomposable resin layer 20. The obtained silicon substrate 102 is fixed. In other words, the thermally decomposable resin layer 20 is disposed between the front surface of the base material 10 and the back surface of the silicon substrate 102 to fix the base material 10 and the silicon substrate 102. At this time, the semiconductor chip 108 is mounted on the main surface of the silicon substrate 102 so as to be electrically connected to the embedded conductive portion 106, and the structure including the silicon substrate 102 and the semiconductor chip 108 is thermally decomposable. It may be arranged on the resin layer 20. Further, after the silicon substrate 102 is disposed on the thermally decomposable resin layer 20, the semiconductor chip 108 may be mounted on the silicon substrate 102. When the semiconductor chip 108 is mounted on the silicon substrate 102 before the silicon substrate 102 is disposed on the thermally decomposable resin layer 20, a low temperature decomposable thermally decomposable resin composition is formed as the thermally decomposable resin layer 20. You may use thing. The decomposition temperature of the low-temperature decomposable thermally decomposable resin composition can be set lower than the curing temperature of the sealing material layer 110, for example.

  Further, the area of the thermally decomposable resin layer 20 can be appropriately set according to the area per unit number of the silicon substrate 102. Therefore, in FIG. 1B, in the in-plane direction of the sealing material layer 110, the interval L1 and the interval L2 of the thin silicon substrate 101 can be freely set, and the sealing for forming the wiring layer 129 is performed. The area of the material layer 110 can be set appropriately.

  Further, as shown in FIG. 4A, a semiconductor sealing resin composition is used to form a plurality of structures (silicon substrate 102 and semiconductor chip 108 on the surface of the thermally decomposable resin layer 20. ) Is formed. The temperature for forming the sealing layer 110 is preferably lower than the temperature at which the thermally decomposable resin layer 20 is decomposed. In this Embodiment, the temperature which forms the sealing layer 110 is specified by the temperature which heats the resin composition for semiconductor sealing. Thereby, before forming the sealing material layer 110, it can suppress that a structure isolate | separates from the thermally decomposable resin layer 20, and a yield falls.

  A method for forming the sealing material layer 110 with the semiconductor sealing resin composition is not particularly limited, and examples thereof include a transfer molding method, a compression molding method, and an injection molding method. A compression molding method in which the above-mentioned misalignment hardly occurs is preferable.

  As said semiconductor sealing resin composition, a liquid resin composition and a solid resin composition can be used.

  When the semiconductor sealing resin composition is a solid resin composition, the step of forming the sealing material layer 110 is performed, for example, by compression molding using a granular resin composition.

First, a resin material supply container in which a granular resin composition is placed is placed between an upper mold and a lower mold of a compression mold. Next, the base material 10 having a plurality of structures (consisting of the silicon substrate 102 and the semiconductor chip 108) is placed on the compression mold by a fixing means such as clamping and suction through the thermally decomposable resin layer 20. The structure is fixed to the upper mold so that the structure is on the lower side (not shown).
Next, the weighed granular resin composition is supplied into a lower mold cavity provided in the lower mold by a resin material supply mechanism such as a shutter constituting the bottom surface of the resin material supply container.
Thereby, the granular resin composition is heated to a predetermined temperature in the lower mold cavity, and as a result, is melted. Then, a sealing material layer 110 that seals the plurality of structures is formed.

  The molding temperature in compression molding is not particularly limited, but is preferably 50 to 200 ° C, particularly preferably 80 to 180 ° C. The molding pressure is not particularly limited, but is preferably 0.5 to 12 MPa, and particularly preferably 1 to 10 MPa. Furthermore, the molding time is preferably 30 seconds to 15 minutes, and particularly preferably 1 to 10 minutes. By setting the molding temperature, pressure, and time within the above ranges, it is possible to prevent both occurrence of an unfilled portion of the sealing material and displacement of the structure.

  In addition, the method for obtaining a granular resin composition is not particularly limited.For example, on the inner side of a rotor composed of a cylindrical outer peripheral portion having a plurality of small holes and a disc-shaped bottom surface, A method in which a melt-kneaded resin composition is supplied and the resin composition is obtained by passing through small holes by centrifugal force obtained by rotating a rotor (hereinafter also referred to as “centrifugal milling method”); After premixing the raw material components with a mixer, heat kneading with a kneader such as a roll, kneader or extruder, cooling and crushing through a pulverized product, removing coarse particles and fine powder using a sieve (Hereinafter also referred to as “grinding and sieving method”): After premixing each raw material component with a mixer, heat kneading is carried out using an extruder equipped with a die having a plurality of small diameters at the screw tip. Along with a strike from a small hole located in the die. How the molten resin come extruded into command shape obtained by cutting with a cutter substantially parallel to slide and rotate on the die face (hereinafter, also referred to as "hot cut method".), And the like. In any method, desired particle size distribution and granule density can be obtained by selecting kneading conditions, centrifugal conditions, sieving conditions, cutting conditions and the like. A particularly preferable production method is a centrifugal milling method, and the granular resin composition obtained thereby can stably express a desired particle size distribution and granule density. Preferred for prevention. In addition, in the centrifugal milling method, the particle surface can be smoothed to some extent, so that the particles are not caught and the frictional resistance with the surface of the conveying path does not increase, and the bridge ( This is also preferable for prevention of clogging) and prevention of retention on the conveyance path. Further, the centrifugal milling method is advantageous in terms of transportability in compression molding because the particles are formed using a centrifugal force from a melted state, so that the voids are included in the particles to some extent and the granule density can be lowered to some extent.

  On the other hand, in the pulverization sieving method, it is necessary to examine a method for treating a large amount of fine powder and coarse particles generated by sieving, but the sieving device and the like are used in existing production lines for semiconductor sealing resin compositions. Therefore, it is preferable in that a conventional production line can be used as it is. The pulverization sieving method expresses the particle size distribution of the present invention, such as selection of sheet thickness when forming a molten resin sheet before pulverization, selection of pulverization conditions and screen during pulverization, selection of sieving during sieving, etc. Since there are many factors that can be controlled independently, it is preferable in that there are many choices of means for adjusting to a desired particle size distribution. The hot cut method is also preferable in that a conventional production line can be used as it is, for example, by adding a hot cut mechanism to the tip of the extruder.

  When the semiconductor sealing resin composition is a liquid resin composition, the step of forming the sealing material layer 110 preferably includes an application step and a molding step. In the coating step, first, the base material with structure 10 is placed in a molding die. Next, a liquid resin composition is applied as a semiconductor sealing resin composition on the arrangement surface (main surface) of the thermally decomposable resin layer 20 with a dispenser or the like. At this time, the liquid resin composition is applied over the entire upper surface and side walls of the structure so as to fill the gaps between the structures. Thereafter, in the molding step, the liquid resin composition is preferably cured under desired curing conditions. Here, it is preferable to perform compression molding. As the curing conditions, for example, the molding pressure is preferably 1 to 10 MPa, more preferably 2 to 8 MPa, and the curing temperature is preferably 110 ° C. to 130 ° C., more preferably 120 ° C. or more. The curing time is preferably 1 minute or more and 1 hour or less, and more preferably 10 minutes or more and 30 minutes or less.

  Through such a process, as shown in FIG. 4A, the periphery of the plurality of structures is sealed with the sealing material layer 110. The sealing material layer 110 is formed on the entire surface of the thermally decomposable resin layer 20.

  Subsequently, as shown in FIG. 4B, the base material 10 is separated from the sealing material layer 110. This separation may be performed in the air, but is preferably performed under reduced pressure as shown below.

When a resin layer whose thermal decomposition temperature is lowered by irradiating active energy rays as the thermally decomposable resin layer 20 is used, the active energy rays are irradiated to the thermally decomposable resin layer 20. , Reduce the thermal decomposition temperature. Specifically, light is irradiated from the back surface of the substrate 10, and light is irradiated to the thermally decomposable resin layer 20 through the substrate 10. The decomposition temperature of the thermally decomposable resin layer 20 is lower than before the active energy ray irradiation.
After irradiation with active energy rays, the thermal decomposition temperature of the thermally decomposable resin layer 20 is, for example, 200 ° C. or less.
Here, the thermal decomposition temperature refers to a temperature at which the weight is reduced by 50% when the temperature of the thermally decomposable resin layer 20 is increased from 25 ° C. to 10 ° C./min in an air stream using a thermogravimetric measuring device.

Next, a laminate including the base material 10, the thermally decomposable resin layer 20, the silicon substrate 102, the semiconductor chip 108, and the sealing material layer 110 is placed in a container (not shown). The gas in the container is sucked by the pump (pressure adjusting means) P, and the pressure is reduced to a pressure lower than the atmospheric pressure. More preferably, the atmosphere is set to 100 Pa or less, and more preferably in a vacuum (5 Pa or less). The lower limit value of the atmospheric pressure in the container is not particularly limited, but is 0.01 Pa, for example, in relation to the performance of the apparatus.
Under this reduced pressure, the laminate is heated above the thermal decomposition temperature of the thermally decomposable resin layer 20 to thermally decompose the thermally decomposable resin layer 20. The thermally decomposable resin layer 20 is thermally decomposed and gasified.

As shown in FIG. 5C, the base material 10 can be separated from one surface of the sealing material layer 110 in which the silicon substrate 102 is embedded by thermally decomposing the thermally decomposable resin layer 20. In the present embodiment, the heating temperature of the thermally decomposable resin layer 20 is preferably performed in a temperature range of 200 ° C. or more and 400 ° C. or less, for example. Thereby, the balance of the ease of isolation | separation by decomposition | disassembly of the thermally decomposable resin layer 20 and suppression of the fall of the yield of a semiconductor element by a heat history becomes favorable.
When separating the sealing material layer 110 and the base material 10, the sealing material layer 110 is formed so that a part of the peripheral edge of the sealing material layer 110 is separated in the direction perpendicular to the surface of the base material 10. There is a method of peeling from the material 10. Further, in order to further reduce the stress on the silicon substrate 102 and the semiconductor chip 108, the base material 10 is slid along the surface direction of the sealing material layer 110, and the base material 10 is peeled off from the sealing material layer 110. May be.

  In the present embodiment, since the residue of the thermally decomposable resin layer 20 is very little or not at all, even if the sealing material layer 110 and the base material 10 are separated by any method, the silicon substrate 102 is formed. The occurrence of cracks is suppressed.

  Thereafter, if necessary, in order to remove the residue of the sealing material layer 110 and the thermally decomposable resin layer 20 attached to the silicon substrate 102, cleaning of one surface of the sealing material layer 110 in which the silicon substrate 102 is embedded is performed. May be performed.

Subsequently, as shown in FIG. 4C, the back surface of the silicon substrate 102 is ground. That is, one surface of the sealing material layer 110 in which the silicon substrate 102 is embedded is ground. When the thickness of the silicon substrate 102 is reduced, the embedded conductive portion 106 is exposed on the back surface thereof. The embedded conductive portion 106 becomes a through plug 105 that penetrates from the main surface to the back surface of the thin silicon substrate 101. The thickness of the thin layer silicon substrate 101 (the ground silicon substrate 102) is not particularly limited, but is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. The thickness of the thin silicon substrate 101 can be appropriately selected based on the thickness and strength of the entire package, the heat dissipation from the semiconductor chip 108, and the like. Further, as a method for grinding the back surface of the silicon substrate 102, a back grinding method using a polishing apparatus or the like is preferable.
In the process of processing the back surface of the silicon substrate 102, the laminate is heated to about 300 ° C., for example. However, the heat-decomposable resin layer 20 is not easily decomposed by this heat, and the silicon substrate 102 is the base material. No peeling from 10.

  As described above, a plate-like pseudo-wafer 111 in which a plurality of semiconductor chips 108 are sealed with the sealing material layer 110 as shown in 4 (c) is obtained. In other words, a plurality of thin silicon substrates 101 are embedded on one surface of the sealing material layer 110. In the sealing material layer 110, one or more semiconductor chips 108 that are electrically connected to the thin silicon substrate 101 are provided. In the pseudo wafer 111, the thin layer silicon substrate 101 includes a through plug 105. For this reason, the pseudo wafer 111 according to the present embodiment can be connected to another mounting substrate via the through plug 105.

  Here, the resin composition for semiconductor encapsulation according to the present invention will be described in detail.

  Hereinafter, the resin composition for semiconductor encapsulation according to the present invention will be described in detail with respect to a solid resin composition, but is not limited thereto. For example, an example in which the solid resin composition is a granular resin composition will be described.

Here, the granular resin composition contains an epoxy resin as a constituent material thereof.
Examples of the epoxy resin include monomers, oligomers, and polymers in general having two or more epoxy groups in one molecule, and the molecular weight and molecular structure thereof are not particularly limited. Specifically, crystalline epoxy resins such as biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, stilbene type epoxy resin, hydroquinone type epoxy resin; cresol novolac type epoxy resin, phenol novolac type epoxy resin, Novolac type epoxy resins such as naphthol novolac type epoxy resins; Phenol aralkyl type epoxy resins such as phenylene skeleton-containing phenol aralkyl type epoxy resins, biphenylene skeleton containing phenol aralkyl type epoxy resins, phenylene skeleton containing naphthol aralkyl type epoxy resins; Triphenolmethane type Trifunctional epoxy resins such as epoxy resins and alkyl-modified triphenolmethane epoxy resins; dicyclopentadiene-modified phenolic epoxy Modified phenol type epoxy resins such as cis-resin and terpene modified phenol type epoxy resins; heterocyclic ring-containing epoxy resins such as triazine nucleus-containing epoxy resins, and the like. Among these, one kind or two or more kinds can be used in combination. .

The granular resin composition preferably contains a curing agent as a constituent material.
The curing agent is not particularly limited as long as it can be cured by reacting with an epoxy resin, and examples thereof include ethylene diamine, trimethylene diamine, tetramethylene diamine, and hexamethylene diamine. Linear aliphatic diamine, metaphenylenediamine, paraphenylenediamine, paraxylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diamino Diphenylsulfone, 4,4′-diaminodicyclohexane, bis (4-aminophenyl) phenylmethane, 1,5-diaminonaphthalene, metaxylenediamine, paraxylenediamine, 1,1-bis (4-aminophenyl) cyclohexane, Dicyanodiamide, etc. Resol type phenol resins such as aniline-modified resole resin and dimethyl ether resole resin; Novolac type phenol resins such as phenol novolac resin, cresol novolac resin, tert-butylphenol novolac resin, nonylphenol novolac resin; phenylene skeleton-containing phenol aralkyl resin, biphenylene Phenol aralkyl resins such as skeleton-containing phenol aralkyl resins; phenol resins having a condensed polycyclic structure such as naphthalene skeleton and anthracene skeleton; polyoxystyrenes such as polyparaoxystyrene; hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride (MTHPA) and other alicyclic acid anhydrides, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), benzophenone Acid anhydrides including aromatic acid anhydrides such as tracarboxylic acid (BTDA); Polymercaptan compounds such as polysulfides, thioesters, thioethers; Isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; Carboxylic acid-containing polyester resins, etc. These organic acids can be used, and one or more of these can be used in combination.

  Of these, compounds having at least two phenolic hydroxyl groups in one molecule are preferably used from the viewpoint of moisture resistance, reliability and the like. Examples of the curing agent include novolak type phenol resins such as phenol novolak resin, cresol novolak resin, tert-butylphenol novolak resin, and nonylphenol novolak resin; resol type phenol resin; polyoxystyrene such as polyparaoxystyrene; phenylene skeleton-containing phenol. Examples thereof include aralkyl resins and biphenylene skeleton-containing phenol aralkyl resins.

Moreover, the granular resin composition can use what contains the inorganic filler as a constituent material.
The inorganic filler is not particularly limited. For example, silica such as fused crushed silica, fused spherical silica, crystalline silica, secondary agglomerated silica; alumina; titanium white; aluminum hydroxide; talc; clay; mica; glass fiber, etc. These can be used, and one or more of these can be used in combination. Among these, fused spherical silica is particularly preferable. Further, the particle shape is preferably infinitely spherical. Furthermore, the amount of inorganic filling can be increased by mixing particles having different particle sizes, but the particle size is set to 0. 0 in consideration of the filling property around the semiconductor element in the lower mold cavity. It is preferable that it is 01 micrometer or more and 150 micrometers or less.

The granular resin composition preferably contains a curing accelerator as a constituent material.
The curing accelerator is not particularly limited, and examples thereof include diazabicycloalkenes such as 1,8-diazabicyclo (5,4,0) undecene-7 and derivatives thereof; amine compounds such as tributylamine and benzyldimethylamine; Imidazole compounds such as 2-methylimidazole; organic phosphines such as triphenylphosphine and methyldiphenylphosphine; tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / tetrabenzoic acid borate, tetraphenylphosphonium / tetranaphthoic acid borate, tetra Tetra-substituted phosphonium / tetra-substituted borates such as phenylphosphonium / tetranaphthoyloxyborate and tetraphenylphosphonium / tetranaphthyloxyborate; Include triphenylphosphine or the like is can be used singly or in combination of two or more of them.

  Furthermore, in addition to the above-mentioned constituent materials, the granular resin composition includes a coupling agent such as γ-glycidoxypropyltrimethoxysilane; a colorant such as carbon black; a natural wax and a synthetic wax, if necessary. Mold release agents such as higher fatty acids or their metal salts, paraffin and polyethylene oxide; low stress agents such as silicone oil and silicone rubber; ion scavengers such as hydrotalcite; flame retardants such as aluminum hydroxide; These various additives may be contained.

  The granular resin composition is preferably such that the proportion of coarse particles of 2 mm or more in the particle size distribution measured by sieving using a JIS standard sieve is 3% by mass or less based on the total resin composition, More preferably, it is 1 mass% or less. This is because the larger the particle size, the larger the mass and volume. Therefore, the greater the proportion of the larger particles, the lower the weighing accuracy at the time of weighing, which contributes to the quality deterioration of the sealed part after compression molding. Or a problem such as clogging at the supply port of the vibration feeder 501 or the resin material supply container may occur. On the other hand, if the range is equal to or less than the above-described upper limit value, a good weighing accuracy can be obtained, thereby reducing the possibility of causing a deterioration in quality in the semiconductor device, and causing problems such as clogging at the supply port. This is because the fear is reduced. Moreover, about the lower limit of the ratio of the coarse grain of 2 mm or more, it does not specifically limit and 0 mass% may be sufficient.

  Moreover, in order to obtain stable weighing accuracy, the granular resin composition has a proportion of fine powder of less than 106 μm in the particle size distribution measured by sieving using a JIS standard sieve is 5% by mass with respect to the total resin composition. Or less, more preferably 3% by mass or less. This means that fine powder of less than 106 μm may cause adhesion during storage of the granular resin composition, adhesion of particles on the conveyance path of the granular resin composition, and adhesion to the conveyance device, resulting in poor conveyance. This may cause problems in continuous productivity and production tact time. On the other hand, when the range is equal to or less than the above-described upper limit value, there is almost no sticking of particles and adhesion to the conveying device, and good continuous productivity and stable productivity can be obtained. Further, the lower limit value of the proportion of fine powder having a particle size of less than 106 μm is not particularly limited, and may be 0% by mass.

  As a method for measuring the particle size distribution of the granular resin composition, for example, a JIS standard sieve having a mesh size of 2.00 mm and 106 μm provided in a low-tap type sieve vibrator is used, and these sieves are left for 20 minutes. The sample is passed through a sieve while vibrating (hammer strike rate: 120 times / min), and classified by passing through a sieve. Mass% of coarse particles remaining on the 2.00 mm sieve with respect to the mass of the sample before classification, fine powder passing through a 106 μm sieve The method of obtaining the mass% of the is preferable because it can embody the characteristics required for actual compression molding. In this method, particles having a high aspect ratio (the minor axis is smaller than the sieve opening and the major axis is larger) may pass through each sieve, but for convenience, they are classified by a certain method. The particle size distribution of the granular resin composition is defined by mass% of the components.

  The granular resin composition preferably has a ratio D1 / D2 between the granule density D1 and the cured product specific gravity D2 of about 0.88 to 0.95, about 0.90 to 0.94. More preferably. When the lower limit value is exceeded, the porosity inside the particles does not become too high, and there is a low possibility that problems such as voids occur in the sealing material layer 110 during compression molding. Moreover, if it is below the above-mentioned upper limit value, the granule density will not become too high, and there will be no problem that the moving speed of the granule becomes slow at the time of conveyance by a conveying means such as the vibration feeder 501. If the moving speed becomes slow, there is a risk of stagnation, which causes problems such as sticking. Furthermore, the granule density D1 of the granular resin composition is preferably 1.95 or less, and more preferably 1.90 or less. When the upper limit value is not exceeded, good transportability is obtained. Further, the lower limit value of the granule density D1 of the granular resin composition is not particularly limited, but is preferably 1.75 or more which is a range in which the porosity inside the particles does not become too high.

  The granule density D1 is measured by sieving the granular resin composition with a JIS standard sieve of 32 mesh (aperture 500 μm) for easy handling, and then adding about 5 g of the granular resin composition on the sieve. A sample weighed to 0.1 mg is used. After filling the pycnometer (capacity 50 cc) with distilled water and adding a few drops of surfactant, the mass of the pycnometer containing distilled water and surfactant is measured. Next, the sample is put into a pycnometer, the mass of the entire pycnometer containing distilled water, a surfactant, and the sample is measured, and calculated according to the following formula (1).

Granule density (g / ml) = (Mp × ρw) / (Mw + Mp−Mt) (1)
ρw: density of distilled water at the measurement temperature (g / ml)
Mw: Mass of a pycnometer filled with distilled water and further added with a few drops of surfactant (g)
Mp: sample mass (g)
Mt: Mass of the pycnometer containing distilled water, surfactant and sample (g)

  The surfactant is used to increase the wetting of distilled water and the sample and minimize the entrainment of bubbles. There are no particular limitations on the surfactant that can be used, and a material that eliminates entrainment of bubbles may be selected.

  Moreover, as a measuring method of hardened | cured material specific gravity D2, the measuring method of hardened | cured material specific gravity by transfer molding which is a simpler method is used. Specifically, the granular resin composition is once compressed into tablets of a predetermined size, and using a transfer molding machine, the mold temperature is 175 ± 5 ° C., the injection pressure is 7 MPa, the curing time is 120 seconds, the diameter is 50 mm × A method of forming a disk having a thickness of 3 mm, calculating the mass and volume, and calculating the specific gravity of the cured product is exemplified.

  Further, the resin composition for semiconductor encapsulation according to the present invention comprises (A) an epoxy resin, (B) an acid anhydride, (C) an inorganic filler, (D) a curing accelerator, and (E) a low stress material. It is the liquid resin composition to contain, Comprising: It is preferable that a solid component contains 80 to 95 weight% with respect to all the liquid resin compositions.

Moreover, it is preferable that the resin composition for semiconductor sealing which concerns on this invention is comprised with the material in which the hardened | cured material hardened | cured on the following conditions satisfy | fills a following formula.
(Tg-25 ° C.) × (α1-α2) × E ′ ≦ 20 MPa
Tg: Glass transition temperature (° C.) of cured product of resin composition for semiconductor encapsulation
E ′: Elastic modulus (Pa) of cured product of resin composition for semiconductor encapsulation
α1: Coefficient of linear expansion (ppm / ° C.) of the cured resin composition for semiconductor encapsulation
α2: Linear expansion coefficient of silicon wafer (ppm / ° C)
Curing conditions: The resin composition for semiconductor encapsulation is cured under the curing conditions of 125 ° C. for 10 minutes and 150 ° C. for 1 hour.

  As the resin composition for semiconductor encapsulation according to the present invention, it is preferable to use a resin composition having low elasticity. Thereby, the internal stress of the sealing material layer 110 obtained by curing the resin composition for semiconductor encapsulation and the silicon wafer is reduced. The above formula (Tg−25 ° C.) × (α1−α2) × E ′ ≦ 20 MPa means that the internal stress between the sealing material layer 110 and the silicon wafer is small. Here, an internal stress difference Δσ between the sealing material layer 110 and the thin silicon substrate 101 is (Tg−25 ° C.) × (α1−α2) × E ′. This Δσ is preferably 20 MPa or less, more preferably 15 MPa or less, and further preferably 10 MPa or less. The internal stress difference Δσ can be set within the above range by appropriately selecting the filling amount of Tg and the inorganic filler, such as the material of the resin composition for semiconductor encapsulation according to the present invention. Thereby, the internal stress difference between the sealing material layer 110 and the thin silicon substrate 101 can be reduced. For this reason, in a structure in which the sealing material layer 110 is stacked on the thin silicon substrate 101 (see, for example, the structure shown in FIG. 4C), warping of the thin silicon substrate 101 can be suppressed. Thereby, in the wafer level package 130, it can suppress that the thin layer silicon substrate 101 warps. Therefore, according to the present embodiment, a semiconductor device having excellent reliability such as connection reliability can be obtained. In addition, since the wafer level package 130 having excellent dimensional stability is obtained, the productivity of the semiconductor device of this embodiment can be improved.

  The glass transition temperature of the resin composition for semiconductor encapsulation according to the present invention is not particularly limited, but is preferably 50 ° C. or higher and 300 ° C. or lower, more preferably 80 ° C. or higher and 200 ° C. or lower. In the present embodiment, the glass transition temperature can be appropriately adjusted by adjusting the crosslinking density. As a method for measuring the glass transition temperature, a thermomechanical analyzer (TMA / SS6100, manufactured by SII) was used to compress a liquid resin composition cured in a square columnar shape from −100 ° C. to 300 ° C. to 5 ° C. A method of measuring the glass transition temperature by measuring the temperature rise at / min is preferred.

  The elastic modulus of the resin composition for semiconductor encapsulation according to the present invention is not particularly limited, but is preferably 5 GPa or more and 30 GPa or less, and more preferably 10 GPa or more and 25 GPa or less. In the present embodiment, the elastic modulus can be appropriately adjusted by adjusting the crosslinking density and the filling amount of the inorganic filler. As a method for measuring the elastic modulus, a viscoelasticity measuring device (DMA-7e, manufactured by PERKIN ELMER) was used to form a liquid resin composition cured in a plate shape from 0 ° C. to 300 ° C. by a three-point bending method. It is preferable to measure the temperature rise at 5 ° C./min and measure the elastic modulus at 25 ° C.

  The linear expansion coefficient in the region of 25 ° C. or more and the glass transition temperature (Tg) or less of the resin composition for semiconductor encapsulation according to the present invention is not particularly limited, but is 1 (ppm / ° C.) or more and 20 (ppm / ° C.) or less. And more preferably 5 (ppm / ° C.) or more and 15 (ppm / ° C.) or less. In the present embodiment, the linear expansion coefficient can be appropriately adjusted by adjusting the filling amount of the inorganic filler. As a method of measuring the linear expansion coefficient, a thermal resin analyzer (TMA / SS6100, manufactured by SII) was used to compress a liquid resin composition cured in a quadrangular prism shape from −100 ° C. to 300 ° C. with a compression method. A method in which the temperature is measured at a rate of ° C / min and the linear expansion coefficient in the glass state region is measured is preferable.

  The linear expansion coefficient in the region of 25 ° C. or more and the glass transition temperature (Tg) or less of the silicon wafer (thin layer silicon substrate 101) according to the present invention is not particularly limited, but is 1 (ppm / ° C.) or more and 10 (ppm / ° C.). ) Or less, more preferably 2 (ppm / ° C.) or more and 5 (ppm / ° C.) or less.

Hereinafter, each component of the liquid resin composition according to the present invention will be described in detail. (A) As an epoxy resin, if it has two or more epoxy groups in one molecule and is liquid at room temperature, molecular weight or The structure is not limited.
For example, novolak type epoxy resin such as phenol novolac type epoxy resin, cresol novolak type epoxy resin, bisphenol F type epoxy resin, N, N-diglycidylaniline, N, N-diglycidyltoluidine, diaminodiphenylmethane type glycidylamine, aminophenol Aromatic glycidylamine type epoxy resin such as glycidylamine type, hydroquinone type epoxy resin, biphenyl type epoxy resin, stilbene type epoxy resin, triphenolmethane type epoxy resin, triphenolpropane type epoxy resin, alkyl-modified triphenolmethane type epoxy Resin, triazine nucleus-containing epoxy resin, dicyclopentadiene modified phenolic epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, Epoxy resins such as phenol aralkyl type epoxy resins having a nylene and / or biphenylene skeleton, aralkyl type epoxy resins such as a naphthol aralkyl type epoxy resin having a phenylene and / or biphenylene skeleton, vinylcyclohexene dioxide, dicyclopentadiene oxide, alicyclic Aliphatic epoxy resins such as alicyclic epoxies such as click diepoxy-adipade. These may be used alone or in combination of two or more.
(A) As an epoxy resin, what contains the structure which the glycidyl ether structure or the glycidylamine structure couple | bonded with the aromatic ring is preferable from a viewpoint of heat resistance, mechanical characteristics, and moisture resistance. (A) When an aliphatic or cycloaliphatic epoxy resin is used as the epoxy resin, it is preferable to limit the amount used from the viewpoint of reliability, particularly adhesiveness. (A) As an epoxy resin, it is preferable that it is finally liquid at room temperature (25 ° C.), but even an epoxy resin that is solid at room temperature is dissolved in a liquid epoxy resin at room temperature, Condition

  (B) An acid anhydride is used as a curing agent. Examples of (B) acid anhydrides include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride Examples include acids, a mixture of 3-methyl-hexahydrophthalic anhydride and 4-methyl-hexahydrophthalic anhydride, tetrahydrophthalic anhydride, nadic anhydride, or methyl nadic anhydride. These are preferable because curing at a low temperature is fast and the glass transition temperature of the cured product is high. Moreover, since it is liquid at normal temperature and its viscosity is low, it is more preferable to use tetrahydrophthalic anhydride as a curing agent. In particular, these may be used alone or in combination of two or more.

  As the curing agent other than the above (B) acid anhydride, any monomer, oligomer or polymer having a functional group that reacts with epoxy in one molecule can be used in combination. As the functional group, for example, a phenol group is preferable. Other curing agents include, for example, phenol novolac resins, cresol novolac resins, dicyclopentadiene modified phenol resins, terpene modified phenol resins, triphenolmethane type resins, phenol aralkyl resins (having a phenylene skeleton, diphenylene skeleton, etc.) And phenols.

As an inorganic filler (C), what is generally used for the sealing material can be used. Examples thereof include fused silica, crystalline silica, talc, alumina, silicon nitride and the like, and these may be used alone or in combination of two or more. Among these, fused silica, crystalline silica, and synthetic silica powder are preferable because the heat resistance, moisture resistance, strength, and the like of the liquid resin composition can be improved. (C) The shape of the inorganic filler is not particularly limited, but the shape is preferably spherical from the viewpoint of viscosity characteristics and flow characteristics.
(C) When the inorganic filler is fused silica, the content of fused silica may be 60% by weight or more and 95% by weight or less in the total liquid resin composition from the balance between moldability and solder crack resistance. More preferably, it is 80 to 95 weight%. If it is less than the lower limit value, the solder cracking resistance accompanying an increase in water absorption may be reduced, and if it exceeds the upper limit value, there may be a problem in the dispensing performance of the liquid sealing resin composition. When the (C) inorganic filler is other than fused silica, the content of the (C) inorganic filler is set within the range of the above content in terms of volume.

  As a hardening accelerator (D), what is necessary is just to accelerate | stimulate reaction of an epoxy group and an acid anhydride, and what is generally used for the sealing material can be used widely. Examples thereof include, but are not limited to, phosphonium salts, triphenylphosphine, imidazole compounds and the like. These curing accelerators may be used alone or in combination. Preferably, the phosphonium salt having the structure of the general formula (2) or the general formula (3), the triphenylphosphine having the structure of the formula (4), or the imidazole compound having the structure of the formula (5) or the formula (6) has a low viscosity. This is effective from the viewpoint of optimization. More preferably, a curing accelerator having the structure of the general formula (2) or an imidazole compound having the structure of the formula (6) is effective from the viewpoint of further reducing the viscosity. As a hardening accelerator of the said General formula (2), following formula (7), Formula (8), Formula (9) etc. are mentioned, for example.

（ただし、式（２）で、Ｒ１、Ｒ２、Ｒ３、及びＲ４は、芳香族もしくは複素環を有する、１価の有機基または１価の脂肪族基であって、それらの内の少なくとも１つは、分子外に放出しうるプロトンを少なくとも１個有するプロトン供与体がプロトンを１個放出してなる基であり、これらは互いに同一であっても異なっていても良い。）

(In the formula (2), R1, R2, R3, and R4 are a monovalent organic group or a monovalent aliphatic group having an aromatic or heterocyclic ring, and at least one of them. Is a group formed by releasing one proton from a proton donor having at least one proton that can be released out of the molecule, and these may be the same or different.

（ただし、式（３）で、Ａｒは置換または無置換の芳香族基を表し、同一分子内の二つの酸素原子は、芳香族炭素位の隣接に位置する。ｎは２〜１２の整数である。）

(In the formula (3), Ar represents a substituted or unsubstituted aromatic group, and two oxygen atoms in the same molecule are located adjacent to the aromatic carbon position. N is an integer of 2 to 12) is there.)

  Moreover, as a hardening accelerator of General formula (3), following formula (10), Formula (11), Formula (12), etc. are mentioned.

  (D) It is preferable that the compounding quantity of a hardening accelerator is 0.1 to 1.0 weight part with respect to 100 weight part of all the liquid sealing resin compositions, More preferably, it is 0.3. It is not less than 0.8 parts by weight. This is because if it is less than the lower limit, curing is slow and productivity is lowered, and if it exceeds the upper limit, the storage stability may be deteriorated.

The blending ratio [(B) / (D)] of (B) acid anhydride and (D) curing accelerator is preferably 3 or more and 35 or less, more preferably 5 or more and 30 or less, and more preferably 10 or more and 20 or less. Particularly preferred. This is because when the blending ratio [(B) / (D)] is less than the lower limit value, the storage stability is deteriorated, and when it exceeds the upper limit value, the curing is slow and the productivity may be deteriorated.
Further, the blending amount of (B) acid anhydride is preferably 2 parts by weight or more and 10 parts by weight or less, more preferably 5 parts by weight or more and 7 parts by weight or less, with respect to 100 parts by weight of the total liquid resin composition. .
(B) When the compounding quantity of an acid anhydride is less than a lower limit, curability will worsen and productivity will fall. And when it exceeds an upper limit, there exists a possibility that moisture resistance reliability may fall.

(E) As a low-stress material, what is necessary is just to make a liquid resin composition low elasticity, and what is generally used for the sealing material can be used widely. For example, ethylene / ethyl acrylate copolymer resin, ethylene / vinyl acetate copolymer resin, butadiene-nitrile rubber, polyurethane, acrylic rubber, acrylonitrile-butadiene rubber, silicone rubber, polyethylene, polypropylene, polybutadiene, olefin copolymer, nitrile rubber And polybutadiene rubber and modified products thereof. Among these, when the low stress material (E) is a liquid rubber, a solid rubber is preferable because a decrease in Tg due to the addition becomes large. Among the solid rubbers, it is more preferable to use core-shell rubber particles because an increase in the linear expansion coefficient can be suppressed. More preferred are core-shell silicone rubber particles.
Moreover, it is preferable that the addition amount of (E) low-stress material is 3 to 30 weight% in a whole liquid resin composition, and 5 to 20 weight% is more preferable. This is because if it is less than the lower limit, the effect of low elasticity cannot be obtained, and if it exceeds the upper limit, the increase in viscosity is high and the productivity may be deteriorated.

  (E) When the low-stress material is core-shell particles, the glass transition temperature of the core part is preferably lower than the glass transition temperature of the shell part and lower than room temperature. In this case, the core and shell need not be the same type of rubber, and it is possible to combine the core with silicone rubber, the shell with acrylic rubber, or the core with butadiene rubber and the shell with acrylic rubber. is there.

  (E) When the low-stress material is a core-shell particle, it is preferably spherical or substantially spherical in that it hardly aggregates. The particle diameter of (C) core-shell particles is preferably 0.01 μm or more and 30 μm or less, and more preferably 0.1 μm or more and 10 μm or less. When the particle diameter is less than the lower limit, the cohesive force becomes strong, the viscosity increases, and the fluidity cannot be maintained. If the upper limit is exceeded, resin clogging may occur in a narrow gap.

  In the liquid resin composition according to the present invention, the solid component is contained in an amount of 80% by weight or more and 95% by weight or less based on the total liquid resin composition. The solid component is a solid component at 25 ° C., and indicates the combined content of the inorganic filler and the solid low-stress material.

  Examples of components that can be used other than the above include mold release agents such as silicone compounds and waxes as antifoaming agents, flame retardants, and the like, and they can be added according to desired characteristics.

  As a method for producing the liquid encapsulating resin composition according to the present invention, for example, each component, additive and the like are dispersed and kneaded using an apparatus such as a planetary mixer, three rolls, two heat rolls, and a laika machine, Produced by defoaming under vacuum.

  Further, the viscosity of the liquid resin composition for encapsulating a semiconductor according to the present invention is preferably 50 Pa · s or more and 2000 Pa · s or less when measured under a temperature condition of 25 ° C. using a viscometer. Preferably, it is 100 Pa · s or more and 500 Pa · s or less. In the present embodiment, the viscosity can be appropriately adjusted by adjusting the raw material viscosity and the filling amount of the inorganic filler. As a method for measuring the linear expansion coefficient, the method for measuring the viscosity is preferably a method in which a 3 ° R7.7 type cone is attached to an E type viscometer and measurement is performed at 25 ° C. under the condition of 5 rpm. By setting the viscosity of the liquid semiconductor sealing resin composition according to the present invention within the above range, uneven coating can be reduced and the productivity of the wafer level package 130 can be improved.

In the liquid semiconductor sealing resin composition according to the present invention, the TI value represented by the following formula is preferably 0.5 or more and 2 or less.
TI value ₌ η 2.5rpm / η 0.5rpm
η _{2.5 rpm} is the viscosity measured at 25 ° C. and 2.5 rpm using a viscometer, and η _{0.5 rpm} is the viscosity measured at 25 ° C. and 0.5 rpm using a viscometer. Preferably there is. In the present embodiment, the TI value can be appropriately adjusted by adjusting the filler filling amount and filler particle size distribution. By setting the TI value of the liquid resin composition for encapsulating a semiconductor according to the present invention within the above range, it has a predetermined viscosity at the time of application, so that contamination due to scattering of the resin can be suppressed and extended. In this case, since the viscosity becomes small, uneven coating can be reduced. Thereby, the productivity of the wafer level package 130 can be improved.

  Although it does not specifically limit as thickness (thickness of a layer thickness direction) of the sealing material layer 110 which concerns on this Embodiment, For example, Preferably they are 100 micrometers or more and 1000 micrometers or less, More preferably, they are 50 micrometers or more and 500 micrometers or less. The distance from the upper surface of the semiconductor chip 108 to the surface of the sealing material layer 110 is not particularly limited, but is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 50 μm or less. Thereby, the internal stress difference with the thin silicon substrate 101 resulting from the sealing material layer 110 is reduced, and a semiconductor device having excellent reliability can be obtained.

The cured product of the liquid resin composition according to the present invention (sealing material layer 110) has an elastic modulus at 25 ° C. of E ₁ , a linear expansion coefficient below the glass transition temperature of α ₁ , and (E ) When the elastic modulus at 25 ° C. of the cured resin composition obtained by substituting the low stress material component with the (C) inorganic filler component is E ₂ , and the linear expansion coefficient below the glass transition temperature is α ₂ , It is preferable that (E ₁ α ₁ −E ₂ α ₂ ) / E ₂ α ₂ <−0.05. That is, in the sealing material layer 110 of the liquid resin composition according to the present invention, it is preferable that the linear expansion coefficient × the room temperature elastic modulus be smaller than a predetermined value. Thereby, since dimensional stability is excellent, generation | occurrence | production of the defect in a semiconductor package can be suppressed.

The cured product of the liquid resin composition according to the present invention the glass transition temperature of the (sealing material layer 110) Tg _1, was replaced the liquid resin composition (E) a low stress material component (C) an inorganic filler component when the glass transition temperature of the cured product of the liquid resin composition was Tg _2, it is preferably _{-0.05 <(Tg 1 -Tg 2)} / Tg 2. Thereby, since heat resistance improves, it can suppress that a defect generate | occur | produces in a semiconductor package.

[Process for forming wiring layer 129]
FIG. 5A to FIG. 6D are process cross-sectional views illustrating the procedure of the wiring layer 129 forming process according to the present embodiment. As the process of forming the wiring layer 129, a process of forming an insulating resin layer (first insulating layer 112) on one surface of the pseudo wafer 111, and a process of forming a wiring on the insulating resin layer (first insulating layer 112) Forming a circuit (conductor 122).
Hereinafter, the process of forming the wiring layer 129 will be described in detail.

  First, as shown in FIG. 5A, the first insulating layer 112 is formed on the main surface of the pseudo wafer 111 on which the through plug 105 is provided. In other words, the first insulating layer 112 is formed on the entire surface of the thin silicon substrate 101 and the sealing material layer 110 provided with the through plugs 105 exposed.

  The material constituting the first insulating layer 112 is not particularly limited, but an organic resin composition is preferable. For example, a polyamide resin such as a polyimide resin or a polybenzoxazole resin, a polybenzocyclobutene resin, a polynorbornene resin, or the like. The photosensitive resin composition which has as a main component can be mentioned. Of these, polyamides such as polyimide resin and polybenzoxazole resin that are excellent in sensitivity and resolution during exposure and development, mechanical properties such as glass transition temperature and elastic modulus, and adhesion to the thin-layer silicon substrate 101. A positive photosensitive resin composition containing a resin as a main component is preferred.

  A method for forming the first insulating layer 112 on the main surface of the pseudo wafer 111 is not particularly limited, but a spin coating method using a spinner, a spray coating method using a spray coater, a dipping method, a printing method, and a roll coating. The law etc. can be used. Thereby, the 1st insulating layer 112 can be formed by apply | coating the photosensitive resin composition and then prebaking and volatilizing the solvent contained in this photosensitive resin composition. At this time, the viscosity of the photosensitive resin composition can be adjusted by appropriately diluting with a solvent or the like according to the forming method.

  The coating amount of the photosensitive resin composition is not particularly limited, but it is preferable to coat the first insulating layer 112 so that the final film thickness is 0.1 to 30 μm. When the final film thickness is less than the lower limit value, it may be difficult to sufficiently exhibit the function of the sealing material layer 110 as an insulating film. Further, when the final film thickness exceeds the upper limit value, it is not only difficult to obtain a fine processing pattern, but processing may take time and throughput may be reduced. The pre-baking temperature is not particularly limited, but is preferably 50 to 150 ° C, and preferably 60 to 130 ° C.

  Next, as shown in FIG. 5B, the first insulating layer 112 corresponding to the position of the through plug 105 is exposed and developed. Thus, a recess (opening 114) is formed in the first insulating layer 112. In the opening 114, the surface of the through plug 105 is exposed on the bottom surface.

  Here, a mechanism for forming the opening 114 will be described. The coating film (first insulating layer 112) of the photosensitive resin composition formed on the main surface of the pseudo wafer 111 is irradiated (exposed) with actinic radiation from above the mask with an exposure device such as a stepper. Thus, an exposed portion (hereinafter referred to as an exposed portion) and an unexposed portion (hereinafter referred to as an unexposed portion) are formed in the first insulating layer 112. The diazoquinone compound in the unexposed area is insoluble in the developer, and the polyamide resin such as polyimide resin and polybenzoxazole resin interacts with the diazoquinone compound, so that the unexposed area is resistant to the developer. To have. On the other hand, in the exposed area, the diazoquinone compound undergoes a chemical change by the action of actinic radiation and becomes soluble in the developer. For this reason, dissolution of the resin in the exposed portion is promoted. By utilizing the difference in solubility between the exposed portion and the unexposed portion to dissolve and remove the exposed portion, only the unexposed portion remains. In this manner, the opening 114 is formed in the first insulating layer 112.

  The exposure method is not particularly limited, but an exposure pattern having an opening at a position corresponding to the through plug 105 is used as a mask, and actinic rays such as X-rays, electron beams, ultraviolet rays, and visible rays are applied to the first insulating layer 112. It is preferable to carry out by irradiation. The wavelength of actinic radiation is preferably 200 to 500 nm. As the actinic radiation, i-line or g-line is preferable.

  Moreover, the opening 114 is formed by dissolving and removing the exposed portion with a developer. The developer is not particularly limited, and examples thereof include a solvent and an alkaline aqueous solution, and an alkaline aqueous solution having a low environmental load is preferable. Although it does not specifically limit as aqueous alkali solution, 1st amines, such as inorganic alkalis, such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, Secondary amines such as diethylamine and di-n-propylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, etc. An aqueous solution of an alkali containing a quaternary ammonium salt or the like, and an aqueous solution containing an appropriate amount of a water-soluble organic solvent or surfactant containing an alcohol such as methanol or ethanol can be preferably used. . Further, as a developing method, for example, a method such as spraying, paddle, dipping, or ultrasonic waves is suitable.

  Next, as illustrated in FIG. 5C, a conductive layer 118 is formed on the surface of the first insulating layer 112. At this time, the conductive layer 118 is preferably formed at least on the wall surface in the opening 114 and on the through plug 105.

  A method for forming the conductive layer 118 is not particularly limited, but a method of sputtering a metal or the like is preferable. Although it does not specifically limit as a metal, Cr, Ti, Cu, etc. are preferable. Further, Cu is preferable from the viewpoint of low resistance, and Ti is preferable from the viewpoint of preventing Cu diffusion of the through plug 105 or the conductor 122 described later.

  Next, as illustrated in FIG. 5D, a resist pattern 120 is formed on the conductive layer 118. In the resist pattern 120, an opening 116 (concave portion) is formed at a position corresponding to the through plug 105. That is, the opening 116 is formed in the resist pattern 120 so that the conductor 122 embedded in the opening 116 in a later step becomes a via and a wiring connected to the through plug 105.

  Although it does not specifically limit as a resist which comprises the resist pattern 120, A liquid or film-like photosensitive resist is mentioned. As a method for forming the resist pattern 120 in the case of using a liquid photosensitive resist, for example, a liquid photosensitive resist is formed by a method such as screen printing so as to cover the entire surface of the conductive layer 118, and then an opening is provided. It exposes through a mask (not shown), Then, it develops with a developing solution. On the other hand, as a method of forming the resist pattern 120 using a film-like photosensitive resist, for example, a film-like photosensitive resist is formed by a technique such as lamination so as to cover the entire surface of the conductive layer 118, and thereafter In the same manner as in the case of a liquid resist.

  Next, as shown in FIG. 5E, a conductor 122 is embedded in the opening 116 of the resist pattern 120. The conductor 122 is preferably formed by a plating method. This conductor 122 is electrically connected to the through plug 105. The metal constituting the conductor 122 is not particularly limited, but Cu is preferable because it has a small electrical resistance and can cope with a high-speed signal. The conductor 122 serves as a via and a wiring that are electrically connected to the through plug 105.

  Next, as shown in FIG. 6A, the resist pattern 120 is removed. Thereafter, the conductive layer 118 directly under the resist pattern 120 (region where the conductor 122 is not formed) is removed. As a result, the conductive layer 118 is left just below the conductor 122.

  A method for removing the conductive layer 118 is not particularly limited, but a method such as reactive ion etching (RIE), in which a residue of the conductive layer 118 hardly remains, is preferable. When removing by a method such as reactive ion etching, the conductor 122 is also slightly reduced in thickness. However, since the conductor 122 is sufficiently thicker than the conductive layer 118, the conductor 122 is It will never be removed.

  Next, as illustrated in FIG. 6B, a second insulating layer 124 is formed so as to cover the first insulating layer 112 and the conductor 122. The material constituting the second insulating layer 124 can be selected from the same materials as those constituting the first insulating layer 112. The materials of the second insulating layer 124 and the first insulating layer 112 may be the same or different. The method for forming the second insulating layer 110 is the same as the method for forming the first insulating layer 112.

  Next, as illustrated in FIG. 6C, an opening 126 is formed in the second insulating layer 124. The opening 126 is formed at a position corresponding to the conductor 122. A method for forming the opening 126 in the second insulating layer 110 is not particularly limited, but is similar to the method for forming the first insulating layer 112.

  Next, as shown in FIG. 6D, bumps 128 are formed in the openings 126 of the second insulating layer 124. The opening 126 is electrically connected to the through plug 105 via the conductor 122 and the conductive layer 118.

  The material constituting the bump 128 is not particularly limited, but tin (Sn), lead (Pb), silver (Ag), bismuth (Bi), indium (In), zinc (Zn), nickel (Ni), antimony (Sb), iron (Fe), aluminum (Al), gold (Au), germanium (Ge), an alloy of at least two metals selected from the group consisting of copper (Cu), or a simple tin Is preferred. Of these, Sn-Pb alloy, Sn-Bi alloy which is lead-free solder, Sn-Ag-Cu alloy, Sn-In alloy, Sn-Ag alloy are considered in consideration of melting temperature and mechanical properties. More preferred is an alloy containing Sn. The shape of the bump 128 is not particularly limited, but a spherical shape is preferable.

  A method for forming the bump 128 is not particularly limited, but, for example, a paste mainly composed of an alloy containing Sn and a flux is applied to the opening 126 of the second insulating layer 124 by a technique such as screen printing, and then, A method of forming by performing solder reflow, a solder ball made of an alloy containing, for example, Sn is placed in the opening 126 of the second insulating layer 124, then flux is applied to the solder ball, Examples of the method include forming by performing solder reflow. In order to perform solder reflow, for example, a solder reflow apparatus is used.

As described above, the rewiring process is performed on the main surface of the pseudo wafer 111 to form the wiring layer 129. Thereby, the wafer level package 130 is obtained.
[Individualization and mounting process]

  Next, the wafer level package 130 is divided. By dividing the wafer level package 130, a plurality of electronic devices 140 of this embodiment are obtained (FIG. 2).

  The wafer level package 130 may be divided into individual semiconductor chips 108 or may be divided into a plurality of semiconductor chips 108. By dividing the semiconductor chip into a plurality of semiconductor chips 108, the semiconductor chip 108 having a plurality of functions can be arranged in one electronic device 140. For this reason, high functionality of the electronic device 140 can be realized.

  A method for dividing the wafer level package 130 is not particularly limited, but the wafer level package 130 can be divided by a technique such as a laser or a dicing saw. Among these, a method using a dicing saw that can be easily divided is preferable.

  Since the electronic device 140 obtained in this manner can route the wiring outside the outer edge of the semiconductor chip 108 and increase the number of input / output wirings, the electronic device 140 can be highly functionalized. it can.

  Next, as shown in FIG. 2, the divided electronic device 140 is mounted on a substrate (interposer 132). For mounting, the bump 128 of the electronic device 140 and the wiring circuit 134 formed on the interposer 132 are connected. In order to connect them, first, when a solder layer is provided on at least the surface of the bump 128, a flux is applied to the bump 128. Next, the electronic device 140 is mounted on the interposer 132 by adjusting the bump 128 and the wiring circuit 134 to the corresponding positions. Next, the bump 128 and the wiring circuit 134 are connected by performing solder connection using a solder reflow apparatus. At this time, the electronic device 140 and the interposer 132 are electrically connected by the metal bonding of the bump 128 and the wiring circuit 134. Thereby, the stacked package 100 shown in FIG. 2 is obtained.

The circuit board which is the interposer 132 is preferably configured mainly with an insulating base material. Examples of the material constituting the substrate include a fiber substrate and a resin film. Examples of the fiber base material include glass fiber base materials such as glass fiber cloth and glass non-woven cloth, or inorganic fiber base materials such as fiber cloth and non-fiber cloth containing inorganic compounds other than glass, aromatic polyamide resin, polyamide resin, aromatic An organic fiber base material composed of organic fibers such as a group polyester resin, a polyester resin, a polyimide resin, and a fluororesin can be used. Moreover, as a resin film base material, for example, polyimide resin film such as polyimide resin film, polyetherimide resin film, polyamideimide resin film, polyamide resin film such as polyamide resin film, polyester resin film such as polyester resin film A film is mentioned. Among these, a polyimide resin film is mainly preferable. Thereby, especially an elasticity modulus and heat resistance can be improved and favorable fine laser workability can be obtained. The base material may contain an inorganic filler (nano filler) having a fine particle diameter.
Moreover, the thickness of a base material is not specifically limited, For example, it can be set to 5-125 micrometers. In particular, by setting the thickness to 12.5 to 100 μm, the flexibility in the direction perpendicular to the surface of the substrate and the stretchability in the in-plane direction can be favorably obtained.

Next, the effect of this Embodiment is demonstrated.
Further, by appropriately setting the intervals L1 and L2 in the in-plane direction of the sealing material layer 110, the mounting area of the thin silicon substrate 101 can be freely increased. Thereby, in the sealing material layer 110, the mounting area of the thin silicon substrate 101 can be freely designed with respect to the unit area of the semiconductor chip 108. Therefore, according to the present embodiment, a semiconductor device excellent in the degree of freedom of the package can be obtained. Moreover, as one of the effects, the area for forming the wiring layer 129 can be increased by increasing the distance between L1 and L2. Thereby, the terminal area per thin silicon substrate 101, that is, the terminal area per semiconductor chip 108 can be set to a desired area.

  Further, the thermally decomposable resin layer 20 is thermally decomposed under reduced pressure. For this reason, gasification of the thermally decomposable resin layer 20 is promoted as a result of being discharged. Thereby, the amount of the thermally decomposable resin layer 20 remaining on the silicon substrate 102 can be reduced. Thereby, a semiconductor device having excellent reliability can be obtained. In addition, since the amount of residue of the thermally decomposable resin layer 20 is small, the cleaning process of the silicon substrate 102 can be simplified or omitted. Thereby, the manufacturing method of the semiconductor device of this embodiment can be simplified. Moreover, the amount of residues of the thermally decomposable resin layer 20 can be reduced more reliably by heating in an atmosphere of 5 Pa or less to thermally decompose the thermally decomposable resin layer 20. Moreover, since the residue of the thermally decomposable resin layer 20 can be reduced also in the base material 10, the base material 10 can be reused.

  In the present embodiment, a low-elasticity resin composition is used as a resin composition for semiconductor sealing that seals the silicon substrate 102 and the semiconductor chip 108 mounted thereon. Thereby, the internal stress difference of the sealing material layer 110 comprised with the hardened | cured material of the resin composition for semiconductor sealing and the silicon substrate 102 becomes small. For this reason, in the silicon substrate 102, since generation | occurrence | production of curvature is suppressed, it is excellent in dimensional stability. Since the wiring layer 129 can be formed on such a silicon substrate 102, a highly reliable wafer level package 130 can be obtained. An effect similar to that of the wafer level package 130 can be obtained also in the electronic device 140 obtained by dividing the wafer level package 130 into pieces and the stacked package 100 formed by mounting the electronic device 140 on the interposer 132. . The form of the semiconductor device of this embodiment is not particularly limited, and any of wafer level package 130, electronic device 140, and stacked package 100 may be used.

  In addition, after the structure in which the semiconductor chip 108 is mounted on the silicon substrate 102 is collectively disposed on the thermally decomposable resin layer 20, a sealing process can be performed. For this reason, the manufacturing method of the semiconductor device of this Embodiment is excellent in productivity. Further, since the wiring layer 129 is formed on the pseudo wafer 111, a desired wiring pattern can be formed. For this reason, the wafer level package 130 excellent in productivity is formed.

Next, a modification of the semiconductor device of this embodiment will be described.
FIG. 10A shows a cross-sectional view of an example of the wafer level package of this modification.
In an example of the wafer level package 301 of this modification, the semiconductor chip 304 has a through plug 303, and the semiconductor chip 312 is electrically connected to the semiconductor chip 304 through the through plug 303. Is formed. Thus, the present modification is basically the same as the present embodiment except that semiconductor chips are stacked.
Hereinafter, this modification will be described in detail with respect to differences from the above-described embodiment.

  In the wafer level package 301 of this modification, a semiconductor chip 304 and a semiconductor chip 312 are stacked on a thin silicon substrate 101. The semiconductor chip 312 is electrically connected to the through plug 105, the conductive layer 118, the conductor 122, and the bump 128 via the through plug 303 of the semiconductor chip 304. As described above, the semiconductor chip 312 can be electrically connected to the external circuit via the bump 128.

  In the semiconductor chip 304, for example, the through plug 303 is electrically connected to the transistor circuit, and is insulated from the elements and wirings in the circuit without being electrically connected to the transistor circuit. You may have. The through plug 303 may be provided at least at a position facing the electrode of the semiconductor chip 312 that needs to be connected. Further, the height of the semiconductor chip 304 having the through plug 303 is not particularly limited, and can be appropriately selected according to various designs.

  As the semiconductor chip 304 and the semiconductor chip 312, various semiconductor elements such as a DRAM and a logic can be used. Further, DRAMs may be stacked, or different types of semiconductor elements of DRAM and logic may be stacked. In this modification, the stacked structure of two-layer semiconductor elements is used, but the number of stacked layers is not particularly limited, and a stacked structure of three or more layers will be described later with respect to the stacking direction. A plurality of semiconductor chips 312 may be provided in the in-plane direction of one semiconductor chip 304.

  The semiconductor chip 304 and the semiconductor chip 312 are sealed with the sealing material layer 110 and the sealing material layer 310, respectively.

Next, a method for manufacturing the semiconductor device according to this modification will be described.
FIG. 8 is a process cross-sectional view illustrating the manufacturing procedure of the semiconductor device according to the modification of the present embodiment.
The manufacturing method of the semiconductor device according to this modification includes the following steps. First, in the step of fixing the base material 10 and the structure including the silicon substrate 102 and the semiconductor chip 108, a first embedded conductive portion (plug 302) is provided on one surface of the first semiconductor element (semiconductor chip 304). The plug 302 of the semiconductor chip 304 and the embedded conductive portion 106 of the silicon substrate 102 are electrically connected. Next, after the step of forming the sealing material layer 110, the other surface of the semiconductor chip 304 is ground together with the upper surface of the sealing material layer 110 so that the plug 302 is exposed on the other surface of the semiconductor chip 304, and the first penetration A plug (through plug 303) is used. Next, a second semiconductor element (semiconductor chip 312) that is electrically connected to the through plug 303 is provided on the other surface of the semiconductor chip 304. Next, a sealing material layer 310 for sealing the semiconductor chip 312 provided on the other surface of the semiconductor chip 304 is formed using the above-described semiconductor sealing resin composition.
Hereinafter, each process is explained in full detail.

  First, as shown in FIG. 8A, steps similar to those in FIGS. 3A to 4A are performed. However, instead of the semiconductor chip 108, a semiconductor chip 304 having a plurality of plugs 302 embedded in one surface is used. As a result, a structure in which the silicon substrate 102 and the semiconductor chip 304 are electrically connected by the through plug 105, the connection part 220, and the plug 302 is obtained. Further, the upper surface and the side wall of the structure are covered with the sealing material layer 110, and the space between the structures is embedded.

  Subsequently, as shown in FIG. 8B, the upper surface of the sealing material layer 110 and the upper surface of the semiconductor chip 304 are ground. This grinding method is the same as that described above. As a result, the plug 302 is exposed on the other surface of the semiconductor chip 304 to form the through plug 303.

  Subsequently, as illustrated in FIG. 8C, the semiconductor chip 312 is mounted on the semiconductor chip 304. As a mounting method, a method similar to the method of mounting the semiconductor chip 304 on the silicon substrate 102 can be used. Thereby, the semiconductor chip 304 and the semiconductor chip 312 are electrically connected via the through plug 303.

  Subsequently, as illustrated in FIG. 8D, a sealing material layer 310 that seals the semiconductor chip 312 is formed in the same manner as the formation of the sealing material layer 110. The sealing material layer 310 uses the same semiconductor sealing resin composition as the sealing material layer 110. Further, the upper surface and the side wall of the semiconductor chip 312 are covered with the sealing material layer 310, and the space between the semiconductor chips 312 is embedded. Thereafter, the base material 10 is separated from the silicon substrate 102 in the same manner as described above.

  After the above steps, the same steps as in FIGS. 4B to 6D are performed. That is, the base material 10 is separated from the silicon substrate 102 to obtain a pseudo wafer. A wiring layer 129 is formed on the pseudo wafer. In this way, a wafer level package 301 as shown in FIG. 10A is obtained. The wafer level package 301 may be separated into individual electronic devices, and this electronic device may be further mounted on a mounting substrate such as an interposer to obtain a stacked package.

This modification can obtain the same effect as the present embodiment.
In addition, since a plurality of semiconductor chips can be stacked in the stacking direction and in the in-plane direction, the number of chips can be increased while suppressing an increase in area. By such three-dimensional stacking, a semiconductor device having an excellent function per unit area can be obtained. The semiconductor chip 312 is laminated with the semiconductor chip 304. Further, the connection distance of the stacked semiconductor chips 312 is shortened, and a high-density and high-speed semiconductor device can be obtained.
Further, when the silicon substrate 102 is previously disposed on the thermally decomposable resin layer 20 in the mounting process, the quality and type of the semiconductor chip can be selected, and the semiconductor chip can be individually mounted and then bonded together. . Since semiconductor chips of different types and the like can be packaged in this way, a semiconductor device manufacturing method with excellent workability can be obtained.

Next, another modification of the semiconductor device of the present embodiment will be described.
FIG. 10B shows a cross-sectional view of another example of the wafer level package of this modification.
An example of the wafer level package 300 of another modification is basically the same as the modification described above except that three or more layers of semiconductor chips are stacked.
Hereinafter, with respect to other modified examples, points different from the above modified examples will be described in detail.
In the wafer level package 300, a plurality of multifunctional semiconductor chips are three-dimensionally stacked. When the side on which the bump 128 is formed is the lower layer side, the uppermost sealing material layer 310 is provided with the semiconductor chip 312 and the resistance element 316. A semiconductor chip 304 having a through plug 303 is provided from the lowermost sealing material layer 110 to the middle sealing material layer 310. In another modification, in the lowermost layer and the middle-layer sealing material layer 310, all semiconductor chips may have through vias, but only some semiconductor chips may have through plugs 303. Good. Also, in the sealing material layer 310 other than the uppermost layer, various semiconductor elements other than the semiconductor chip, such as a resistance element, may be provided. In another modification example, a four-layer structure is used, but the number of layers is not particularly limited, and a ten-layer or more structure may be used.

  Further, the semiconductor chip 304 may have a plurality of through plugs 303. Thereby, a plurality of semiconductor elements (for example, the semiconductor chip 304 having the through plug 303, the semiconductor chip 312 and the resistance element 316) can be mounted in the in-plane direction of the semiconductor chip 304. Examples of the mounting method include a bonding method using the wiring layer 314 formed by a method such as a solder bonding method using the adhesive layer 210 having flux activity as described above. A wiring layer 314 can be formed across a plurality of semiconductor chips 304. For this reason, the freedom degree of arrangement | positioning of the semiconductor chip formed on the wiring layer 314 further improves.

  The layer thickness of each sealing material layer 310 is not particularly limited, but is preferably 100 μm or more and 1000 μm or less, and more preferably 50 μm or more and 500 μm or less. In the uppermost layer, the distance from the upper surface of the semiconductor chip 312 to the surface layer of the sealing material layer 310 is not particularly limited, but is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less.

Next, a method for manufacturing a semiconductor device according to another modification will be described.
9 (a) and 9 (b) are the same as the steps shown in FIGS. 8 (a) and 8 (b).
Subsequently, as shown in FIG. 9C, the semiconductor chip 306 is mounted on the semiconductor chip 304. The semiconductor chip 306 has a plug 308. For this reason, the through plug 303 of the semiconductor chip 304 and the plug 308 of the semiconductor chip 306 are electrically connected. As a mounting method, a method similar to the method of mounting the semiconductor chip 304 on the silicon substrate 102 can be used.

  Subsequently, as illustrated in FIG. 9D, a sealing material layer 310 that seals the semiconductor chip 306 is formed in the same manner as the formation of the sealing material layer 110. The sealing material layer 310 uses the same semiconductor sealing resin composition as the sealing material layer 110.

  Thereafter, a series of steps composed of FIGS. 9B to 9D are repeated a plurality of times to stack semiconductor chips. Thereafter, the same steps as in FIGS. 4B to 6D are performed in the same manner as in the above modification. That is, the base material 10 is separated from the silicon substrate 102 to obtain a pseudo wafer. A wiring layer 129 is formed on the pseudo wafer. In this way, a wafer level package 300 as shown in FIG. 10B is obtained.

  In other modified examples, the same effects as those of the present embodiment and the modified example can be obtained. In addition, since it can be three-dimensionally mounted at a high density, a smaller, high-speed, high-functional or multifunctional semiconductor device can be obtained.

  Needless to say, the above-described embodiment and a plurality of modifications can be combined within a range in which the contents do not conflict with each other. Further, in the above-described embodiments and modifications, the structure of each part has been specifically described, but the structure and the like can be changed in various ways within a range that satisfies the present invention.

10 substrate 20 thermally decomposable resin layer 30 silicon wafer 100 laminated package 101 thin layer silicon substrate 102 silicon substrate 104 non-through hole 105 through plug 106 embedded conductive portion 108 semiconductor chip 110 encapsulant layer 111 pseudo wafer 112 first Insulating layer 114 Opening 116 Opening 118 Conductive layer 120 Resist pattern 122 Conductor 124 Second insulating layer 126 Opening 128 Bump 129 Wiring layer 130 Wafer level package 132 Interposer 134 Wiring circuit 140 Electronic device 204 Electrode pad 206 Solder bump 208 Electrode pad 210 Adhesive layer 220 Connection part 300 Wafer level package 301 Wafer level package 302 Plug 303 Through plug 304 Semiconductor chip 306 Semiconductor chip 308 Plug 310 Sealing material layer 31 The semiconductor chip 314 a wiring layer 316 resistance element

Claims (11)

Forming a thermally decomposable resin layer on the substrate;
A substrate having a plurality of embedded conductive portions provided on a main surface thereof on the thermally decomposable resin layer; and a first semiconductor element electrically connected to the embedded conductive portion on the substrate. Arranging a plurality of structures and fixing the base material and the structures via the thermally decomposable resin layer;
Forming a sealing material layer that seals the plurality of structures on the thermally decomposable resin layer using a semiconductor sealing resin composition;
Decomposing the thermally decomposable resin layer by heat treatment, and separating the base material from the sealing material layer, thereby exposing the back surface of the substrate of the structure;
Grinding the back surface of the substrate to expose a buried conductive portion on the back surface to form a through plug.   2. The semiconductor device according to claim 1, wherein, in the step of forming the sealing material layer, a temperature at which the semiconductor sealing resin composition is heated is lower than a temperature at which the thermally decomposable resin layer is thermally decomposed. Manufacturing method.   The method for manufacturing a semiconductor device according to claim 1, wherein the heat treatment is performed in a temperature range of 200 ° C. or more and 400 ° C. or less.   4. The method for manufacturing a semiconductor device according to claim 1, wherein a 5% weight reduction temperature of the thermally decomposable resin layer is 400 ° C. or less. 5.   The heat-decomposable resin layer contains at least one selected from the group consisting of a polycarbonate resin, a polyester resin, a polyamide resin, a polyimide resin, a polyether resin, and a polyurethane resin. The method for manufacturing a semiconductor device according to any one of the above.   The method for manufacturing a semiconductor device according to claim 1, wherein the thermally decomposable resin layer includes a photoacid generator.   The method for manufacturing a semiconductor device according to claim 5, wherein the polycarbonate-based resin includes at least one structural unit selected from the group consisting of propylene carbonate, cyclohexylene carbonate, butylene carbonate, and norbornene carbonate. In the step of fixing the base material and the structure, a plurality of first embedded conductive portions are provided on one surface of the first semiconductor element, and the first semiconductor element includes the first conductive element. The embedded conductive portion and the embedded conductive portion of the silicon wafer are electrically connected,
After the step of forming the encapsulant layer, the other surface of the first semiconductor element is ground together with the upper surface of the encapsulant layer, and the other surface of the first semiconductor element is filled with the first embedding layer. Exposing the embedded conductive portion to form a first through plug;
Providing a second semiconductor element electrically connected to the first through electrode on the other surface of the first semiconductor element;
Forming a sealing material layer for sealing the second semiconductor element provided on the other surface of the first semiconductor element, using the resin composition for semiconductor sealing. The method for manufacturing a semiconductor device according to claim 1. In the step of fixing the base material and the structure,
Providing the first semiconductor element on the substrate so as to be electrically connected to the embedded conductive portion;
The semiconductor device according to claim 1, further comprising a step of arranging a plurality of the structures including the substrate and the first semiconductor element on the thermally decomposable resin layer. Manufacturing method. A step of forming an insulating resin layer on one surface of the sealing material layer in which a plurality of the structures are embedded and the through plug is exposed;
The method for manufacturing a semiconductor device according to claim 1, further comprising: forming a wiring circuit on the insulating resin layer.   A semiconductor device obtained by the method for manufacturing a semiconductor device according to claim 1.

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