JP2010510653A - Board-on-chip package and manufacturing method thereof - Google Patents

Abstract

A board on chip (BOC) type semiconductor package includes a substrate having an opening and a semiconductor die having a conductive region on an active surface. The die is placed on the substrate so that the active surface faces the upper surface of the substrate and completely covers the opening of the substrate. The conductive area of the active surface of the die is exposed at the opening of the substrate. The die is bonded to the substrate using an adhesive, and is electrically bonded to the substrate by wire bonding through the opening of the substrate. The wire bond is protected by a sealing material that fills the opening of the substrate. Solder balls are embedded in the lower surface of the substrate in the outer region of the encapsulant. The package is characterized in that no encapsulant is present on the inactive side of the die and no encapsulant is present on the side of the die.

Description

The present invention relates to a semiconductor package and a method for manufacturing the same.

BACKGROUND OF THE INVENTION A recent achievement in semiconductor packaging technology for DRAM (Dynamic Random Access Memory) memory devices is a board-on-chip or BOC package. These packages, also called window-type semiconductor packages, include a substrate having an opening that penetrates the substrate, and the semiconductor chip or die is bonded to the opening on the upper side of the substrate by an adhesive. The chip is mounted face down so that the active (or active) surface of the chip faces the substrate and is partially exposed to the opening. The plurality of bonding wires connect the active surface of the die to the lower surface of the substrate through the opening. Forming a first encapsulant on the lower surface of the substrate, filling the opening to seal the bonding wire, forming a second encapsulant on the upper surface of the substrate, Seal the sides. A plurality of solder balls are attached to the lower surface of the base material and disposed outside the first sealing material.

  In practice, the BOC package can be manufactured using at least two different methods. In one method, a printable adhesive paste is applied to the substrate and placed in a B-stage prior to die attachment to a non-tacky state. In general, multiple dies are mounted on a single substrate so that multiple packages can be made on a single board. After the molding and solder ball installation, the packages are separated from each other to produce a single package. FIG. 1 shows a top view of a package in a general embodiment of the method, and FIG. 2 shows a cross-sectional view thereof, with a pattern in which a die 11 can be placed on an opening 100 in a substrate 10 and bonded. The agent 12 is printed on the upper side surface 101 of the substrate 10. After attaching the die 11 onto the adhesive 12, a wire bond 13 is formed on the back side 102 of the substrate 10 from the wire bond pad 112 on the active side 111 of the die 11 through the opening 100.

  In the molding process, the sealing material 15 is applied to the wire bond 13, the inactive side 110 of the die 11, and the side 113 of the die 11. After molding, the solder balls 14 are attached to the back side 102 of the substrate 10 and the packages are separated from each other by a cutting operation. FIG. 3 shows a package cross section representing another general aspect of this method, where the inactive side 110 of the die 11 is not sealed, but the side 113 of the die 11 is sealed. Yes.

  This conventional method has several drawbacks. As shown in FIGS. 1 and 2, the adhesive 12 is not printed along the entire periphery of the opening 100, leaving a gap G between the active surface 111 of the die 11 and the upper surface 101 of the substrate 10. . The gap G in the adhesive 12 requires the use of the sealing material 15 on the non-active side and / or the side of the die, but during sealing the wire bond 13, the sealing material 15 It flows between the material 10 and the die 11 and flows out along the side 113 and the inactive side 110 of the die 11. Furthermore, the inactive side 110 and / or side 113 of the die 11 is encapsulated in the mold material, and its vast mold area can result in warping of the substrate due to the thermal stress inherent in the molding process. This requires placing the die in a structure that can relieve the stress of the substrate during the molding process.

  FIG. 4A shows a general structure that allows multiple packages to be manufactured from a single substrate 10. In this structure, the adhesive 12 can be printed on the peripheral region of the opening 100 of the substrate 10, and the die can be placed on the adhesive 12 so as to cover the opening 100 later. In this structure, stress is released by incorporating unmolded substrate regions between the blocks of the molded package, and the substrate 10 includes slits 104 in the regions between the molded package blocks. FIG. 4B is an enlarged view of this structure, showing that the stress relief area provided by the slit 104 needs to use a much larger substrate area than the memory package itself requires. This waste is highly undesirable because the substrate 10 is one of the expensive materials used in memory packages. Finally, the temperature and pressure inherent in the molding process can apply thermal stress on the semiconductor die and reduce yield.

  FIG. 5 is a top view of a BOC package manufactured using the second method, and FIG. 6 is a cross-sectional view thereof. In this method, a tape adhesive 17 having a hole at a location corresponding to the opening 100 of the base material is pasted on the tape attachment region 105 on the upper side surface 101 of the base material 10, and the hole of the adhesive tape is formed. Align with material openings. In this way, the adhesive tape 17 is interposed between the active surface 111 of the die 11 and the upper side surface 101 of the substrate without forming any gap between the die 11 and the substrate 10. After attaching the die 11 onto the tape adhesive 17, a wire bond 13 is formed from the wire bond pad 112 on the active side 111 of the die 11 to the back side 102 of the substrate 10 through the opening 100. Next, the sealing material 15 is applied on the wire bond 13 in one process, and the second sealing material 16 is applied on the side 113 of the die 11 in the molding process. After molding, the solder balls 14 are attached to the back side 102 of the substrate 10 and the packages are separated from each other in a cutting process.

  In another embodiment, encapsulant is applied to the non-active side of the die and the sides of the die. This method solves the problem of the gap between the active surface of the die and the upper surface of the substrate due to the area adjacent to the substrate opening, which is not covered by the adhesive, but has a significant drawback. Have. First, the use of tape adhesives is much more expensive than flowable adhesives such as printable pastes. Second, the die may not be perfectly aligned on the tape, leaving some gaps under the die. Finally, this method requires that the sides and / or back side of the die be sealed during the molding process. Thus, as with the method described above, it involves significant substrate waste and die thermal stress.

  The flowable paste for die attachment is used to eliminate gaps between the active surface of the die and the top side of the substrate, to reduce substrate waste, and to seal the back and / or sides of the die. Having a semiconductor package and a method of manufacturing the package that overcomes the disadvantages of both methods by allowing the thermal stress generated in the die to be eliminated during the molding process used to stop, Very useful.

SUMMARY OF THE INVENTION The present invention comprises: a) a substrate (or substrate) having an upper side, a lower side opposite the upper side, an opening through the upper side and the lower side, and a wire bond pad on the lower side; b ) A semiconductor die having an active side having one or more conductive regions and an inactive side opposite the active side, the active side being the upper side and the lower side of the substrate A semiconductor die placed on the substrate, placed over the opening penetrating the side and completely covering the opening; c) placed between the upper side of the substrate and the active side of the die An adhesive that joins them, except for the conductive area, the active side of the die being completely covered by the adhesive, d) the conductive area on the active side of the die through the opening in the substrate On the bottom side of the substrate. A plurality of conductive bonding wires connected to the bond pads, e) applied on the underside of the substrate, sealing the bonding wires and filling the openings in the substrate, and f) of the sealing material A semiconductor package comprising a plurality of solder balls embedded on the underside of the substrate in the outer region, wherein no encapsulant is present on the non-active side of the die and sealed to the side of the die The semiconductor package is characterized in that no stopper is present.

  In another aspect, the present invention provides: a) a substrate having an upper side, a lower side opposite the upper side, an opening extending through the upper side and the lower side, and a wire bond pad on the lower side; b) providing at least one semiconductor die having an active side having one or more conductive regions and a non-active side opposite the active side; c) bonding after the die is attached to the substrate Apply flowable adhesive in an adhesive pattern on the upper side of the substrate so that the agent surrounds the opening and has at least the same size as the die footprint, including the opening, d) optional E) solidify the flowable adhesive to a non-tacky state, e) place the die on the substrate, the active side is placed over the opening through the upper and lower sides of the substrate, and the opening Completely covering the active surface of the die. The areas are exposed at the substrate openings, and the active surface of the die is completely covered by the adhesive, except for the conductive areas, f) optionally the adhesive is cured, and g) multiple conductive A conductive bonding wire is attached and the conductive area on the active side of the die is connected to the wire bond pad on the lower side of the substrate through the opening in the substrate, and h) sealed on the lower side of the substrate. Apply a stop to seal the bonding wire, fill the opening in the substrate, i) cure the seal, and j) on the underside of the substrate in the outer region of the seal, A method of manufacturing a semiconductor package comprising embedding a plurality of solder balls, characterized in that there is no sealing step for the inactive side of the die and no sealing step for the side of the die. A method for manufacturing a semiconductor package.

  In a third aspect, the present invention provides: a) a substrate having an upper side, a lower side opposite the upper side, an opening penetrating the upper side and the lower side, and a wire bond pad on the lower side; b Adhesive) after providing at least one semiconductor die having an active side having one or more conductive regions and a non-active side opposite the active side, and c) attaching the die to the substrate Applying a flowable adhesive in an adhesive pattern on the active side of the die so that it surrounds the opening and has at least the same size as the die footprint, including the opening, and d) optionally E) solidify the flowable adhesive to a non-tacky state, e) place the die on the substrate, the active side is placed over the opening through the upper and lower sides of the substrate, and the opening is completely And conductive areas on the active surface of the die Exposed at the substrate opening, the active surface of the die is completely covered by the adhesive, except for the conductive areas, f) optionally, the adhesive is cured, and g) a plurality of conductive bonds. Attach the wire and connect the conductive area on the active side of the die to the wire bond pad on the lower side of the substrate through the opening in the substrate, h) the encapsulant on the lower side of the substrate Applying a plurality of seals to the bonding wire, filling the openings in the substrate, i) curing the sealant, and j) a plurality of surfaces on the lower surface of the substrate in the outer region of the sealant A method of manufacturing a semiconductor package comprising embedding solder balls, characterized in that there is no sealing step for the non-active side of the die and there is no sealing step for the side of the die It is a manufacturing method of a package.

  In a fourth aspect, the present invention is a base material for manufacturing a board-on-chip semiconductor package, comprising a front side surface, a back side surface facing the front side surface, and an opening penetrating the front side surface and the back side surface. The base material is characterized in that there is no mold stress release region.

  The present invention can be more fully understood by reading the following detailed description with reference to the accompanying drawings.

FIG. 1 (prior art) is a top view of a conventional semiconductor package. FIG. 2 (prior art) is a cross-sectional view of a conventional semiconductor package. FIG. 3 (Prior Art) is a cross-sectional view of another embodiment of a conventional semiconductor package. FIG. 4A (prior art) is a top view of a conventional print pattern of a BOC type package on a substrate. FIG. 4B (prior art) is an enlarged view of a conventional print pattern of a BOC type package on a substrate. FIG. 5 (prior art) is a top view of another embodiment of a conventional semiconductor package. FIG. 6 (prior art) is a cross-sectional view of another embodiment of a conventional semiconductor package. FIG. 7 is a top view of the semiconductor package of the present invention. FIG. 8A is a cross-sectional view of one embodiment of a semiconductor package of the present invention. FIG. 8B is a cross-sectional view of another embodiment of the semiconductor package of the present invention. 9A to 9E are top views of the base material assembled based on the manufacturing method of the present invention. 10A and 10B illustrate the printed pattern on the wafer used in another aspect of the present invention. FIG. 11 is a top view of a substrate of a BOC package characterized by the absence of a mold stress release region. 12A and 12B are top views of a substrate having an adhesive print pattern that represents two additional aspects of the present invention. FIG. 13 is a top view of a substrate having an adhesive print pattern that represents another aspect of the present invention.

Definitions As used herein, the term “alkyl” refers to a branched or unbranched saturated hydrocarbon group having from 1 to 24 carbon atoms, for example, methyl (“Me”), ethyl (“Et”) , N-propyl, isopropyl, n-butyl, isobutyl, t-butyl, octyl, decyl and the like.

  As used herein, the term “effective amount” of a compound, product, or composition means a sufficient amount of the compound, product, or composition to provide the desired result. As pointed out below, the exact amount required will vary from package to package, depending on the particular compound, product or composition used, its method of use, and the like. Therefore, it is not always possible to specify an accurate amount. However, an effective amount can be determined by one of ordinary skill in the art using only routine experimentation.

  As used herein, the term “suitable” is used to mean something that is compatible with a compound, product, or composition for a given purpose. One of ordinary skill in the art can determine suitability for a given purpose only through routine experimentation.

  As used herein, “substituted” is generally used to have hydrogen or other atoms in which a carbon or appropriate heteroatom is removed and replaced with another moiety (or group, moiety). Means to. Furthermore, “substitution” is intended to mean a substitution that does not alter the basic and novel utility of the following compounds, products, or compositions used in the present invention.

  As used herein, “B-staging” (and variants or derivatives thereof) is used to indicate processing of a material by heating or irradiation, if the material is dissolved or dispersed in a solvent E.g., evaporating the solvent with or without partially curing the material, and if the material remains as it is without solvent, partially curing the material to have a sticky state Or make it more solidified. If the material is a flowable adhesive, B-staging provides very low flow without fully curing and after bonding one article to another using the adhesive Further curing may be performed. The decrease in fluidity may be effected by solvent evaporation, partial growth or curing of the resin or polymer, or both.

  As used herein, a “printable paste” is any liquid adhesive that can be printed on a surface such as a substrate, die, or wafer.

DETAILED DESCRIPTION OF THE INVENTION FIG. 7 represents a top view illustrating one embodiment of a semiconductor package according to the present invention, and FIG. 8A represents a cross-sectional view thereof. The base material 20 has an upper side surface 201 and a lower side surface 202 opposite to the upper side surface, and has at least one opening 200 formed so as to penetrate the upper side surface 201 and the lower side surface 202 of the base material 20. . Substrates contemplated for the present invention are rigid or semi-rigid (not flexible tapes) made primarily of common resin materials including, but not limited to, BT resins, epoxy resins, and FR-4 ). The substrate can be of any size, but is generally between 20 mm x 100 mm and 100 mm x 250 mm and a thickness between 0.1 and 0.6 mm.

  In one aspect, an adhesive application (or application) region 206 is defined on the upper surface 201 of the substrate 20 near the opening, and the region 206 is at least as wide as the die footprint, including the opening. That's it.

  In one aspect, the substrate is designed so that it does not have a stress relief region when molded. FIG. 11 illustrates a top view of one embodiment that can constitute a substrate, where the substrate 20 has a front side 201 and a back side opposite the front side, and the front side 201 and back side. It includes an opening 200 through which 202 can be formed to form a wire bond therethrough. This substrate structure is characterized by the absence of mold stress relief regions. The packages and manufacturing methods described in the present invention have many of the same advantages of saving substrate area, which is possible by not requiring the mold of the package to seal the back and / or sides of the die. Modifications and similar arrangements can occur to those skilled in the art.

  The semiconductor die 21 or chip is placed on the substrate 20, the active side 211 of the die 21 is placed on the flowable adhesive 22, and the adhesive 22 is attached to the active surface 211 of the die 21 and the upper side surface 201 of the substrate. Intervene between them. The active surface 211 is larger than the opening 200, completely covers the opening 200, and the conductive region on the active surface 211 of the die 21 can be exposed to the opening 200 of the substrate 20. The active surface 211 of the die 21 is completely covered by the flowable adhesive 22 except for the conductive region, and no gap is formed between the die and the substrate.

  The semiconductor chip or die 21 may be of any size and thickness, for example, a silicon IC component such as a DRAM having a thickness in the range of 0.05 to 0.4 mm. In other embodiments, the die 21 may be a silicon digital signal processor or may be made of gallium arsenide, indium phosphide, or any other semiconductor material. Manufacturing a semiconductor die 21 having an active surface 211 (also known as a front side or front side) that forms electrical elements and circuits, and a non-active surface 210 (also known as a back side or rear side) opposite the active surface 211 . The active surface 211 has a plurality of wire bond pads 212 formed in at least one conductive region, which wire the chip active surface 211 to the wire bond pads 203 on the lower side 202 of the substrate 20. Used to bond and form electrical connections between them.

  In one aspect, the semiconductor die has bonding pads at multiple locations, for example, both the center and the edge of the die. In this aspect, the substrate includes a plurality of openings corresponding to each of these bonding pad locations.

  The adhesive 22 joins the upper surface 201 of the substrate 20 to the active side 211 of the die 21. The die 21 is placed on the substrate 20 so that the conductive region on the die 21 including the wire bond pad 212 is over the opening 200 of the substrate 20 and completely covers the opening 200. In this way, the die 21 is attached to the base material 20 so that there is no adhesive coating gap between the die 21 and the base material 20, but the wire bond 23 is placed on the bond pad 212 contained in the conductive region. The conductive region is exposed so that can be formed.

  In one embodiment, the adhesive 22 is applied to the upper side surface 201 of the substrate 20. In another aspect, the adhesive 22 is applied to the active side 211 of the die 21 prior to dicing from the wafer. In another aspect, the adhesive 22 is applied to the active side 211 of the die 21 after dicing from the wafer.

  Any using flowable adhesives including, but not limited to, stencil printing, screen printing, inkjet printing, or other similar printing, spreading, dispensing, or spraying methods The adhesive 22 may be applied to either the die 21 or the substrate 20 using a method. After the die 21 is attached to the substrate 20, the adhesive 22 is applied in a pattern such that the adhesive 22 completely covers the active surface 211 of the die 21 except for the conductive areas. The conductive region can be aligned with the opening 200 of the substrate 20 in the absence of the adhesive 22 and can be wire bonded to a bond pad 212 included in the conductive region. The amount of adhesive required to cover the die and the particular printed pattern will depend on the adhesive flowability, bonding pressure, and other similar parameters and can be determined by one skilled in the art without undue experimentation. it can. The thickness of the adhesive is typically 10 to 250 microns when wet.

  FIG. 12A illustrates a printed pattern on the substrate 20 in one embodiment of the present invention, where the adhesive 22 is applied to the upper side 201 of the substrate 20 and the adhesive 22 is the opening 200 of the substrate 20. And has at least the same area as the die footprint, but does not necessarily completely cover the upper surface 201 of the substrate 20. This embodiment can be used to minimize the use of adhesive. This type of printed pattern results in a package as shown in the cross-sectional view of FIG. 8A, where the adhesive 22 extends to the outer edge of the die 21 or just slightly beyond the edge.

  FIG. 12B illustrates a printed pattern on the substrate 20 in one embodiment of the present invention, where the adhesive 22 is applied to the entire upper surface 201 of the substrate 20 excluding the openings 200. This aspect can be used to simplify the printing process because fewer individual printing elements are required than in the pattern shown in FIG. 12A. The printed pattern illustrated in FIG. 12B results in the package shown in the cross-sectional view of FIG. 8B where the adhesive 22 extends well beyond the outer edge of the die 21.

  FIG. 10 illustrates a printed pattern in another aspect of the present invention, excluding the conductive area V without adhesive, leaving the conductive areas of the die exposed to align over the openings in the substrate. Therefore, the adhesive 22 is applied to the active surface 211 of the wafer 26 in a pattern that covers (all dies after dicing the wafer).

  The adhesive used to attach the die must be flowable when applied to a substrate or wafer, and the adhesive can be stencil printed, screen printed, inkjet printed, or other similar printing, spreading, It can be applied via dispensing or spraying methods. Adhesives are not preformed films or tapes that are applied, preformed, laminated, or punched to a substrate. After application to either the wafer or die, the adhesive can be solidified, B-staged, or cured, and no longer has the proper fluidity for the application methods listed above.

  In one aspect, the adhesive is a printable paste.

  The selection of an appropriate adhesive is based on downstream manufacturing factors such as die type and dimensions, substrate type, package shape, and reflow temperature and required reliability. Adhesives typically include several types of polymers or curable resins, including thermoplastic resins, thermosetting resins, elastomers, thermosetting rubbers, or combinations thereof. The adhesive may or may not contain a solvent. The polymer or curable resin is generally the major component, except for fillers that may be present. Other ingredients commonly used in adhesive compositions may be added at the discretion of one of ordinary skill in the art and include, but are not limited to, curing agents, fluxing agents, wetting agents, Flow control agents, adhesion promoters, and defoamers are included. A curing agent is any material or combination of materials that initiates, propagates, and accelerates the curing of the adhesive and includes accelerators, catalysts, initiators, and hardeners. The adhesive composition may also include a filler, in which case the filler is present in an amount of no more than 95% of the total composition.

  The resin and polymer used for the adhesive may be solid, liquid, or a combination of the two. Suitable resins include epoxy, acrylate or methacrylate, maleimide, vinyl ether, polyester, poly (butadiene), polyimide, benzocyclobutene, siliconized olefin, silicone resin, styrene resin, cyanate ester resin, or polyolefin, or siloxane. It is.

構造を有するものであって、 In one embodiment, solid aromatic bismaleimide (BMI) resin powder is included in the adhesive. Suitable solid BMI resin is

Having a structure,

X is an aromatic group, and typical aromatic groups include

ｎは１〜３であり、

n is 1 to 3,

および

and

が含まれる。

Is included.

  Bismaleimide resins with these X cross-linking groups are commercially available and are available, for example, from Sartomer (USA) or HOS-Technic GmbH (Austria).

を有するものが含まれ、ｎは１〜３で、Ｘ^１は脂肪族または芳香族基である。代表的なＸ^１構成要素は、ポリ（ブタジエン）、ポリ（カーボネート）、ポリ（ウレタン）、ポリ（エーテル）、ポリ（エステル）、単純炭化水素、およびカルボニル、カルボキシル、アミド、カルバメート、尿素、またはエーテルのような官能基を含有する単純炭化水素を含む。これらの種類の樹脂は市販されており、例えば、Ｎａｔｉｏｎａｌ Ｓｔａｒｃｈ ａｎｄ Ｃｈｅｍｉｃａｌ Ｃｏｍｐａｎｙおよび大日本インキ化学工業株式会社から入手することができる。 In another aspect, the maleimide resin used in the adhesive composition has a general structure.

N is 1 to 3, and X ¹ is an aliphatic or aromatic group. Exemplary X ¹ components are poly (butadiene), poly (carbonate), poly (urethane), poly (ether), poly (ester), simple hydrocarbon, and carbonyl, carboxyl, amide, carbamate, urea, or Includes simple hydrocarbons containing functional groups such as ethers. These types of resins are commercially available and can be obtained from, for example, National Starch and Chemical Company and Dainippon Ink and Chemicals, Inc.

In a further aspect, the maleimide resin is

(C ₃₆ represents a straight or branched chain of 36 carbon atoms (with or without a cyclic moiety)),

および

and

から成る群から選択される。

Selected from the group consisting of

を有するものが含まれ、 Suitable acrylate resins include general structure

Including

n is 1 to 6, R ¹ is —H or —CH ₃ , and X ² is an aromatic or aliphatic group. Exemplary X ² components include poly (butadiene), poly (carbonate), poly (urethane), poly (ether), poly (ester), simple hydrocarbon, and carbonyl, carboxyl, amide, carbamate, urea, Or simple hydrocarbons containing functional groups such as ethers are included. Commercially available materials include butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, n-lauryl (meth) acrylate, alkyl (available from Kyoeisha Chemical Co., Ltd.) (Meth) acrylate, tridecyl (meth) acrylate, n-stearyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, 1,4 -Butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, perfluorooctylethyl (meth) acrylate, 1,10- Candiol di (meth) acrylate, nonylphenol polypropoxylate (meth) acrylate, and polypentoxylate tetrahydrofurfuryl acrylate; polybutadiene urethane dimethacrylate (CN302, NTX6513) and polybutadiene dimethacrylate (CN301) available from Sartomer Company, Inc. , NTX6039, PRO6270); polycarbonate urethane diacrylate (ArtResin UN9200A) available from Negami Kogyo Co., Ltd .; acrylated aliphatic urethane oligomers (Ebecryl 230, 264, 265, 270, 284, 4830) available from Radcure Specialties, Inc. , 4833, 4834, 4835, 4866 , 4881, 4883, 8402, 8800-20R, 8803, 8804); polyester acrylate oligomers (Ebecryl 657, 770, 810, 830, 1657, 1810, 1830) available from Radcure Specialties, Inc, and Sartomer Company, Inc. Available epoxy acrylate resins (CN104, 111, 112, 115, 116, 117, 118, 119, 120, 124, 136) are included. In one embodiment, the acrylate resin is selected from the group consisting of isobornyl acrylate, isobornyl methacrylate, lauryl acrylate, lauryl methacrylate, poly (butadiene) with acrylate functionality and poly (butadiene) with methacrylate functionality. The

を有するものが含まれ、ｎは１〜６であり、Ｘ^３は芳香族または脂肪族基である。代表的なＸ^３構成要素には、ポリ（ブタジエン）、ポリ（カーボネート）、ポリ（ウレタン）、ポリ（エーテル）、ポリ（エステル）、単純炭化水素、およびカルボニル、カルボキシル、アミド、カルバメート、尿素、またはエーテルのような官能基を含有する単純炭化水素が含まれる。市販の樹脂には、Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｓｐｅｃｉａｌｉｔｙ Ｐｒｏｄｕｃｔｓ（ＩＳＰ）から入手可能なシクロヘキサンジメタノールジビニルエーテル、ドデシルビニルエーテル、シクロヘキシルビニルエーテル、２−エチルヘキシルビニルエーテル、ジプロピレングリコールジビニルエーテル、ヘキサンジオールジビニルエーテル、オクタデシルビニルエーテル、およびブタジールジビニルエーテル；Ｓｉｇｍａ−Ａｌｄｒｉｃｈ、Ｉｎｃから入手可能なＶｅｃｔｏｍｅｒ４０１０、４０２０、４０３０，４０４０，４０５１、４２１０、４２２０、４２３０、４２６０、５０１５が含まれる。 Suitable vinyl ether resins include general structure

N is 1-6, and X ³ is an aromatic or aliphatic group. Representative ^{X 3} entities include poly (butadiene), poly (carbonates), poly (urethanes), poly (ether), poly (esters), simple hydrocarbons, and carbonyl, carboxyl, amide, carbamate, urea, Or simple hydrocarbons containing functional groups such as ethers are included. Commercially available resins include cyclohexanedimethanol divinyl ether, dodecyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, dipropylene glycol divinyl ether, hexanediol divinyl ether, octadecyl vinyl ether, and butadiol available from International Specialty Products (ISP). Divinyl ethers; Vector 4010, 4020, 4030, 4040, 4051, 4210, 4220, 4230, 4260, 5015 available from Sigma-Aldrich, Inc.

  Suitable poly (butadiene) resins include poly (butadiene), epoxidized poly (butadiene), maleated poly (butadiene), acrylated poly (butadiene), butadiene-styrene copolymers, and butadiene-acrylonitrile copolymers. Is included. Commercially available materials include homopolymer butadiene available from Sartomer Company, Inc (Ricon 130, 131, 134, 142, 150, 152, 153, 154, 156, 157, P30D); butadiene available from Sartomer Company, Inc. And random copolymers of styrene (Ricon 100, 181, 184); maleated polybutadiene available from Sartomer Company, Inc (Ricon 130MA8, 130MA13, 130MA20, 131MA5, 131MA10, 131MA17, 131MA20, 156MA17); obtained from Sartomer Company, Inc. Possible acrylated poly (butadiene) (CN302, NTX6513, CN301, N TX6039, PRO6270, Riacryl 3100, Riacryl 3500); epoxidized poly (butadiene) available from Sartomer Company, Inc. (Polybd 600, 605); and Epolead PB 3600 available from Daicel Chemical Industries, Ltd .; and available from Hanse Chemical Acrylonitrile and butadiene copolymers (Hycar CTBN series, ATBN series, VTBN series and ETBN series) are included.

  Suitable epoxy resins include bisphenol, naphthalene, and aliphatic type epoxies. Commercially available materials include bisphenol type epoxy resins (Epiclon 830LVP, 830CRP, 835LV, 850CRP available from Dainippon Ink and Chemicals, Inc .; naphthalene type epoxy (Epiclon HP4032) available from Dainippon Ink and Chemicals, Inc .; Aliphatic epoxy resins available from Ciba Specialty Chemicals (Araldite CY179, 184, 192, 175, 179), available from Union Carbide Corporation (Epoxy 1234, 249, 206), and available from Daicel Chemical Industries, Ltd. (EHPE-3150) Other suitable epoxy resins include alicyclic epoxy resins, bisphenol A epoxy resins, bisphenols F type epoxy resin, novolak type epoxy resins, biphenyl type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene - phenol epoxy resins, reactive epoxy diluents, and mixtures thereof.

を有するシリコーンおよびジビニル材料の選択的ヒドロシル化反応によって得られ、 Suitable silicone olefin resin has general structure

Obtained by a selective hydrosilation reaction of silicone and divinyl materials having

n ₁ is 2 or greater, n ₂ is 1 or greater, and n ₁ > n ₂ . These materials are commercially available and can be obtained, for example, from the National Starch and Chemical Company.

を有する反応性シリコーン樹脂が含まれ、 Suitable silicone resins include general structure

A reactive silicone resin having

n is 0 or any integer, X ⁴ and X ⁵ are hydrogen, methyl, amine, epoxy, carboxyl, hydroxy, acrylate, methacrylate, mercapto, phenol, or vinyl functional groups, and R ² and R ³ are — It may be H, —CH ₃ , vinyl, phenyl, or any hydrocarbon structure having more than two carbon atoms. Commercially available materials include Shin-Etsu Silicon International Trading (Shanghai) Co. KF8012, KF8002, KF8003, KF-1001, X-22-3710, KF6001, X-22-164C, KF2001, X-22-170DX, X-22-173DX, X-22-174DX, available from Ltd. X-22-176DX, KF-857, KF862, KF8001, X-22-3367, and X-22-3939A are included.

を有する樹脂が含まれ、 Suitable styrene resins include general structure

A resin having

n is 1 or greater, R ⁴ is —H or —CH ₃ , and X ⁶ is an aliphatic group. Representative ^{X 3} entities include poly (butadiene), poly (carbonates), poly (urethanes), poly (ether), poly (esters), simple hydrocarbons, and carbonyl, carboxyl, amide, carbamate, urea, Or simple hydrocarbons containing functional groups such as ethers are included. These resins are commercially available and can be obtained from, for example, National Starch and Chemical Company or Sigma-Aldrich.

を有するものが含まれ、ｎは１またはそれより大きく、Ｘ^７は炭化水素基である。代表的なＸ^７構成要素には、ビスフェノール、フェノールまたはクレゾールノボラック、ジシクロペンタジエン、ポリブタジエン、ポリカーボネート、ポリウレタン、ポリエーテル、またはポリエステルが含まれる。市販の材料には、Ｈｕｎｔｓｍａｎ ＬＬＣから入手可能なＡｒｏＣｙ Ｌ−１０、ＡｒｏＣｙ ＸＵ３６６、ＡｒｏＣｙ ＸＵ３７１、ＡｒｏＣｙ ＸＵ３７８、ＸＵ１７８７．０２Ｌ、およびＸＵ７１８７．０７Ｌ；Ｌｏｎｚａ Ｇｒｏｕｐ Ｌｉｍｉｔｅｄから入手可能なＰｒｉｍａｓｅｔ ＰＴ３０、Ｐｒｉｍａｓｅｔ ＰＴ３０ Ｓ７５、Ｐｒｉｍａｓｅｔ ＰＴ６０、Ｐｒｉｍａｓｅｔ ＰＴ６０Ｓ、Ｐｒｉｍａｓｅｔ ＢＡＤＣＹ、Ｐｒｉｍａｓｅｔ ＤＡ２３０Ｓ、Ｐｒｉｍａｓｅｔ ＭｅｔｈｙｌＣｙ、およびＰｒｉｍａｓｅｔ ＬＥＣＹ；Ｏａｋｗｏｏｄ Ｐｒｏｄｕｃｔｓ，Ｉｎｃから入手可能な２−アリルフェノールシアネートエステル、４−メトキシフェノールシアネートエステル、２，２−ビス（４−シアナトフェノール）−１，１，１，３，３，３，−ヘキサフルオロプロパン、ビスフェノールＡシアネートエステル、ジアリルビスフェノールＡシアネートエステル、４−フェニルフェノールシアネートエステル、１，１，１−トリス（４−シアナトフェニル）エタン、４−クミルフェノールシアネートエステル、１，１−ビス（４−シアナトフェニル）エタン、２，２，３，４，４，５，５，６，６，７，７−ドデカフルオロオクタンジオールジシアネートエステル、および４，４’−ビスフェノールシアネートエステルが含まれる。 Suitable cyanate ester resins include general structure

Wherein n is 1 or greater and X ⁷ is a hydrocarbon group. Representative X ⁷ components include bisphenol, phenol or cresol novolac, dicyclopentadiene, polybutadiene, polycarbonate, polyurethane, polyether or polyester. Commercial materials include AroCy L-10, AroCy XU366, AroCy XU371, AroCy XU378, XU1787.02L, and XU7187.07L available from Huntsman LLC; PT60, Primaset PT60S, Primaset BADCY, Primaset DA230S, Primaset MethylCy, and Primaset LECY; 2-Allylphenol cyanate ester, 4-methoxyphenol cyanate ester, 4-methoxyphenol cyanate ester, available from Oakwood Products, Inc. Phenol) -1,1, , 3,3,3-hexafluoropropane, bisphenol A cyanate ester, diallyl bisphenol A cyanate ester, 4-phenylphenol cyanate ester, 1,1,1-tris (4-cyanatophenyl) ethane, 4-cumyl Phenol cyanate ester, 1,1-bis (4-cyanatophenyl) ethane, 2,2,3,4,4,5,5,6,6,7,7-dodecafluorooctanediol dicyanate ester, and 4 , 4'-bisphenol cyanate ester.

  Suitable polymers for the adhesive composition include polyamide, phenoxy, polybenzoxazine, acrylate, cyanate ester, bismaleimide, polyethersulfone, polyimide, benzoxazine, vinyl ether, siliconized olefin, polyolefin, polybenzoxazole, polyester, Polystyrene, polycarbonate, polypropylene, poly (vinyl chloride), polyisobutylene, polyacrylonitrile, poly (methyl methacrylate), poly (vinyl acetate), poly (2-vinylpridine) (poly (2-vinylpridine)), cis-1,4 -Polyisoprene, 3,4-polychloroprene, vinyl copolymers, poly (ethylene oxide), poly (ethylene glycol), polyformaldehyde, Riacetaldehyde, poly (b-propiolacetone), poly (10-decanoate), poly (ethylene terephthalate), polycaprolactam, poly (11-undecanoamide), poly (m-phenylene-terephthalamide), poly (tetramethylene- m-benzenesulfonamide), polyester polyacrylate, poly (phenylene oxide), poly (phenylene sulfide), polysulfone, polyimide, polyetheretherketone, polyetherimide, fluorinated polyimide, polyimidesiloxane, isoindoloquinazolinedione, poly Thioetherimido polyphenylquinoxaline, polyquinoxalone, imidoaryl ether phenylquinoxaline copolymer, polyquinoxaline, polybenzimidazole, polybenzo Kisazoru, polynorbornene, poly (arylene ether), polysilane, parylene, benzocyclobutene, hydroxy (benzoxazole) copolymer, poly (ancillary Ren siloxane), and polybenzimidazole are further included.

  Other suitable materials included in the adhesive composition include monovinyl aromatic hydrocarbons and conjugated dienes such as styrene-butadiene, styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), styrene. Rubber polymers such as block copolymers of ethylene-butylene-styrene (SEBS) and styrene-ethylene-propylene-styrene (SEPS) are included.

  Other suitable materials contained in the adhesive composition include ethylene-vinyl acetate polymers, other ethylene esters and copolymers such as ethylene methacrylate, ethylene n-butyl acrylate and ethylene acrylic acid; polyethylene and polypropylene. Polyvinyl acetate and their random copolymers; polyacrylates; polyamides; polyesters; and polyvinyl alcohol and their copolymers.

  Suitable thermoplastic rubbers contained in the adhesive composition include carboxy-terminated butadiene-nitrile (CTBN) / epoxy adducts, acrylate rubbers, vinyl-terminated butadiene rubbers, and nitrile butadiene rubbers (NBR). In one embodiment, the CTBN epoxy adduct consists of about 20-80 wt% CTBN and about 20-80 wt% diglycidyl ether bisphenol A: bisphenol A epoxy (DGEBA). Various CTBN materials are available from Noveon Inc. Various bisphenol A epoxy materials are available from Dainippon Ink Chemical Co., Ltd. and Shell Chemicals. NBR rubber is commercially available from Zeon Corporation.

  Suitable siloxanes contained in the adhesive formulation include at least one siloxane moiety that provides backbone and permeability and at least one reactive moiety that can react to react to form a new covalent bond. An elastic polymer comprising a pendant hanging from the skeleton is included. Examples of suitable siloxanes include 3- (tris (trimethylsilyloxy) silyl) -propyl methacrylate, n-butyl acrylate, glycidyl methacrylate, acrylonitrile, and cyanoethyl acrylate; 3- (tris (trimethylsilyloxy) silyl) -propyl methacrylate; Included are elastic polymers made from n-butyl acrylate, glycidyl methacrylate, and acrylonitrile; and 3- (tris (trimethylsilyloxy) silyl) -propyl methacrylate, n-butyl acrylate, glycidyl methacrylate, and cyanoethyl acrylate.

  If the adhesive composition requires a curing agent, the choice is based on the polymer chemistry used and the processing conditions used. As a curing agent, the composition may use aromatic amines, allyl cyclic amines, aliphatic amines, tertiary phosphines, triazines, metal salts, aromatic hydroxyl compounds, or combinations thereof. Examples of such catalysts include imidazole (eg, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methyl Imidazole, 1-propyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenyl Imidazole, 1-guanaminoethyl-2-methylimidazole and adducts of imidazole and trimellitic acid); tertiary amines (eg, N, N-dimethylbenzylamine, N, N-dimethylaniline, N, N-dimethyltoluidine, N , N-dimethyl -P-anisidine, p-halogeno-N, N-dimethylaniline, 2-N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, triethylenediamine, N, N , N ′, N′-tetramethylbutanediamine, N-methylpiperidine); phenols (eg, phenol, cresol, xylenol, resorcin, and phloroglucin); organometallic salts (eg, lead naphthenate, lead stearate, naphthene) Zinc oxide, zinc octylate, tin oleate, dibutyltin maleate, manganese naphthenate, cobalt naphthenate and iron acetylacetone); and inorganic metal salts (eg stannic chloride, zinc chloride and aluminum chloride); peroxides (For example, benzoic peroxide Acid, lauroyl peroxide, octanoyl peroxide, acetyl peroxide, parachlorobenzoyl peroxide and di-t-butyl diperphthalate); acid anhydrides (eg carboxylic acid anhydrides, maleic acid anhydrides, phthalic acid anhydrides) , Lauric anhydride, pyromellitic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, hexahydropyromellitic anhydride and hexahydrotrimellitic anhydride); azo compounds (eg, azoisobutyrate) Nitrile, 2,2′-azobispropane, m, m′-azoxystyrene, hydrazone), and mixtures thereof.

  In another embodiment, the curing accelerator is triphenylphosphine, alkyl-substituted imidazole, imidazolium salt, onium salt, quaternary phosphonium compound, onium borate, metal chelate, 1,8-diazabicyclo [5.4.0]. It may be selected from the group consisting of unde-7-cene or mixtures thereof.

  In another aspect, the curing agent may be either a free radical initiator or a cationic initiator based on whether a radical or ionic curable resin is selected. If a free radical initiator is used, it is present in an effective amount. Effective amounts are generally 0.1 to 10 weight percent of the organic compound (excluding any filler present). Free radical initiators include peroxides such as butyl peroctoate and dicumyl peroxide, and azo compounds such as 2,2′-azobis (2-methyl-propanenitrile) and 2,2′-azobis (2- Methyl-butanenitrile).

  If a cationic initiator is used, it is present in an effective amount. Effective amounts are generally 0.1 to 10 weight percent of the organic compound (excluding any filler present). Suitable cationic curing agents include dicyandiamide, phenol novolac, adipic dihydrazide, diallyl melamine, diaminomalconitile, BF3-amine complexes, amine salts and modified imidazole compounds.

  Metal compounds can also be used as cyanate ester based accelerators, including but not limited to metal naphthenates, metal acetylacetonates (chelates), metal octoates, metal acetates, metal halides, metal imidazoles. Complexes and metal amine compounds are included.

  Other cure accelerators that may be included in the adhesive formulation include triphenylphosphine, alkyl-substituted imidazoles, imidazolium salts, and onium borates.

  In some cases, it may be desirable to use more than one type of cure for the adhesive composition. For example, both cationic and free radical initiators may be desirable, in which case free radical curable and ionic curable resins may be used in the composition. These compositions contain an effective amount of initiator for each type of resin. Such compositions can be initiated with a cationic initiator using, for example, UV irradiation, and can be completed with a free radical initiator when heat is applied in subsequent processing steps. .

  One or more fillers can be included in the adhesive composition and are usually added to improve rheological properties and reduce stress. Since the adhesive comes into contact with the active side of the die, the filler is electrically non-conductive. Examples of suitable non-conductive fillers include alumina, aluminum hydroxide, silica, vermiculite, mica, wollastonite, calcium carbonate, titanium oxide, sand, glass, barium sulfate, zirconium, carbon black, organic fillers, and for example Included are halogenated ethylene polymers such as tetrafluoroethylene, trifluoroethylene, vinylidene fluoride, vinyl fluoride, vinylidene chloride, and vinyl chloride. The filler particles can be of any suitable dimensions, ranging from nanosize to several mm. The selection of dimensions for any particular package structure is within the knowledge of those skilled in the art. The filler may be present in an amount from 0 to 95% by weight of the total composition.

  In one embodiment, the adhesive formulation includes a spacer, which is a particle added for the purpose of controlling the bondline to a predetermined thickness. The selection of an appropriate spacer is based on the package structure and adhesive formulation and can be selected by one skilled in the art without undue experimentation. Suitable spacers include, but are not limited to, silica, Teflon, polymer or elastomeric material. They can range in size from 25 to 150 microns and are used in effective amounts.

  In another aspect, a coupling agent can be added to the adhesive composition. Generally, the coupling agent is a silane, for example, an epoxy type silane coupling agent, an amine type silane coupling agent, or a mercapto type silane coupling agent. When a coupling agent is used, it is used in an effective amount. Typical effective amounts are up to 5% by weight.

  In a further aspect, a surfactant can be added to the adhesive composition. Suitable surfactants include silicone, polyethylene glycol, polyoxyethylene / polyoxypropylene block copolymer, ethylenediamine-based polyoxyethylene / polyoxypropylene block copolymer, polyol-based polyoxyalkylene, fatty alcohol-based polyoxy Alkylene and fatty alcohol polyoxyalkylene alkyl ethers are included. When used, an effective amount of surfactant is used, with typical effective amounts being up to 5% by weight.

  In another embodiment, the adhesive composition can contain a wetting agent. The choice of wetting agent is based on the requirements for use and the resin chemistry used. When used, wetting agents are used in effective amounts, with typical effective amounts being up to 5% by weight. Examples of suitable wetting agents include Fluorad FC-4430 Fluorosurfactant available from 3M, Clariant Fluowet OTN, BYK W-990 available from 3M, Surfynol 104 Surfactant, Crompton L80 Included are propylene glycol, Gama-Butylactone, castor oil, glycerin or other fatty acids, and silanes having a preferred molecular weight Mw greater than 240.

  In a further aspect, the adhesive composition can include a flow control agent. The choice of flow control agent is based on the requirements for use and the resin chemistry used. When used, the flow control agent is present in an effective amount, which is an amount up to 5% by weight. Examples of suitable flow control agents include Cab-O-Sil TS720 available from Cabot, Aerosil R202 or R972 available from Degussa, fumed silica, fumed alumina, or fumed metal oxide.

  In another aspect, an adhesion promoter can be included in the adhesive composition. The choice of adhesion promoter is based on the requirements for use and the resin chemistry used. When used, the adhesion promoter is used in an effective amount, which is an amount up to 5% by weight. Examples of suitable adhesion promoters include silane coupling agents such as Z6040 epoxy silane or Z6020 amine silane available from Dow Corning; A186 Silane, A187 Silane, A174 Silane, or A1289 available from OSI Silquest; Organosilane SI264 available; Joho Chemical CBT-1 carbobenzotriazole available from Johoku Chemical Co., Ltd .; functional benzotriazole; thiazole; titanate; and zirconate.

  In a further aspect, a defoamer (antifoam) can be added to the adhesive composition. The choice of defoamer is based on the requirements for use and the resin chemistry used. When used, the defoamer is used in an effective amount, which is an amount up to 5% by weight. Examples of suitable defoamers include Antifoam 1400, DuPont Modoflow, and BYK A-510 available from Dow Corning.

  In some embodiments, these compositions are formulated with a tacky resin to improve adhesion and impart tack. Examples of adhesive resins include natural resins and modified natural resins: polyterpene resins; phenol-modified terpene resins; coumarone indene resins; aliphatic and aromatic petroleum hydrocarbon resins; phthalate esters; hydrogenated hydrocarbons, hydrogen Rosin and hydrogenated rosin esters.

  In certain embodiments, the adhesive composition can include other ingredients, such as diluents such as liquid polybutene or polypropylene; petroleum waxes such as paraffin and microcrystalline wax, polyethylene greases, hydrogenated animals. , Fish and vegetable oils, mineral oils and synthetic waxes, naphthenic or paraffinic mineral oils.

  Other additives such as stabilizers, antioxidants, impact modifiers, and colorants known to those skilled in the art can also be added to the adhesive composition.

  A general solvent having an appropriate boiling point in the range of 25 ° C. to 230 ° C. can be used for the adhesive composition. Examples of solvents that can be used include ketones, esters, alcohols, ethers, and other common solvents that are stable and dissolve the resin in the composition. Suitable solvents include γ-butyrolactone, propylene glycol methyl ethyl acetate (PGMEA), and 4-methyl-2-pentanone.

  After applying the adhesive to the substrate or die, it can be dried and / or B-staged at any processing step. In one aspect of the invention, the adhesive is allowed to solidify and become non-tacky so that the substrate, wafer, or die can be stored and / or moved to separate locations prior to attaching the semiconductor die. In general, the adhesive is sufficiently solidified so that the adhesive coated substrate, die, or wafer can be stacked on top of each other without the use of inserts. The adhesive can be solidified by various methods based on the adhesive formulation used.

  In one aspect, the adhesive is a thermoplastic material that is applied at a temperature above the melting point so that it is flowable. In this case, the adhesive solidifies by being cooled at a temperature lower than the melting point and / or the softening point of the adhesive.

  In another aspect, the adhesive includes at least a liquid thermosetting resin and a solvent. In this aspect, the adhesive and the substrate are sufficiently heated to evaporate the solvent and partially cure the one or more thermosetting resins, causing the adhesive to solidify and become non-tacky. Or very low fluidity.

  In another aspect, the adhesive includes a solid thermosetting resin dissolved in a solvent. After application to the substrate, the adhesive and substrate are heated sufficiently to allow the solvent to evaporate, allowing the adhesive to solidify by leaving a non-tacky thermosetting resin coating on the substrate. To a non-tacky or very low fluidity state.

  In another aspect, the adhesive includes at least one liquid thermosetting resin. After application to the substrate, the adhesive is solidified by sufficiently heating the adhesive and the substrate so that the thermosetting resin is partially non-tacky or very low fluidity. To a non-tacky or very low fluidity state.

  One skilled in the art will appreciate that the adhesive may include a combination of resins that can be dried, B-staged, and cured in combination with the mechanism. For example, the formulation may be B-staged through the use of ultraviolet radiation and may be cured by the use of heat in the downstream manufacturing process after die attach. The formulation may include a combination of resins having two separate cure temperatures, by curing the first resin by heating the substrate at the first (cold side) temperature and solidifying the entire adhesive formulation It can be made into a non-tacky state, and an adhesive agent can be solidified. In this case, the second resin having the second (high temperature side) curing temperature is cured in a processing step that follows the attachment of the die.

  The adhesive may or may not require curing. If the adhesive requires curing, curing may be performed as a separate processing step or in conjunction with another processing operation such as solder reflow or wire bonding.

  When using a B-staging process, the B-staging temperature is generally in the range of 80 ° C. to 200 ° C., and depending on the particular adhesive formulation selected, B staging is 1 minute to 2 hours. Within a range of hours. The time and temperature of the B-staged profile will vary depending on the adhesive composition, and various compositions can be devised to provide a B-staged profile suitable for a particular industrial manufacturing process.

  In another aspect, the adhesive is not solidified prior to die attach. In this case, the die is placed on the substrate while the adhesive is still flowable. This allows a fillet to form around the die when the die is pressed against the adhesive. The fluidity of the adhesive and the pressure used to place the die can be adjusted to provide the desired amount of fillet for each particular package structure. In this embodiment, care must be taken to prevent the adhesive from flowing into the openings in the substrate. This is because this prevents wire bonding.

  FIG. 13 illustrates an exemplary printed pattern of another aspect of the present invention, wherein the adhesion is such that there is a small non-flow region F that is not coated with adhesive 22 around the substrate opening 200. The agent 22 is applied to the front side surface 201 of the substrate 20. When the die is attached, the fluidity of the adhesive allows the fillet to form around the outside of the die. The fluidity of the adhesive causes the adhesive 22 to flow into a non-flow region F around the opening 200, which completely covers the active surface of the die except for the conductive (wire bond pad) region. That is, it does not flow into the opening 200 of the substrate 20.

  When the curing step is used for die attachment bonding, it may be performed before wire bonding, during wire bonding, or after wire bonding and sealing. Curing of the die attach bond may be a separate processing step or may occur simultaneously with the curing process of the encapsulant.

  Curing temperatures are generally in the range of 80 ° C. to 250 ° C. for die attach bonding, and depending on the specific resin chemistry and curing agent selected, curing can be in the range of seconds to 120 minutes. carry out. The time and temperature of the curing profile of each adhesive composition is different, and various compositions can be designed to provide a curing profile suitable for a particular industrial manufacturing process.

  If the adhesive is curable, it may be cured by exposure to heat, ultraviolet (UV) irradiation, or a combination thereof. The curing conditions for each adhesive composition vary, and various compositions can be designed to provide a curing profile suitable for a particular industrial manufacturing process.

  In one aspect, the adhesive has a pot life of at least 2 months after being in the B stage. This long pot life may be achieved by any means commonly used to extend the pot life of a dried or partially advanced adhesive, including but not limited to A means is the use of one or more of (i) at least one latent curing agent, (ii) a high concentration of thermoplastic resin, and (iii) a high molecular weight resin in the adhesive formulation. . After the adhesive is stored at room temperature, the pot life is tested by examining the fluidity of the adhesive under standard die attach conditions. If the adhesive can wet the die surface with standard die attach conditions, it is still within the pot life. However, if the adhesive has insufficient fluidity to wet the die, it is not useful for attaching the die and is considered outside its pot life.

  A plurality of wire bonds 23 are formed through the openings 200 of the substrate 20 in a wire bonding process. Bonding wire 23 is bonded to exposed wire bond pad 212 on the conductive area of die 21 and bonded to wire bond pad 203 on lower side 202 of substrate 20 through corresponding opening 200 in substrate 20. . In this way, the active surface 211 of the die 21 can be electrically connected to the lower surface 202 of the substrate. The bonding wire 23 is made of any metal that conducts electrical signals such as gold.

  A sealing material 25 is formed on the wire bond 23 on the lower side surface 202 of the substrate 20 so as to surround or seal the bonding wire 23 and fill the opening 200 of the substrate 20. The encapsulant 25 may be applied by dispensing, potting, printing, molding, or other similar methods. The encapsulant 25 may be any material that protects the bonding wire 23 during subsequent manufacturing process steps, and the package includes, but is not limited to, epoxy and silicone. The encapsulant 25 is cured under conditions that match the selected encapsulant composition. The time and temperature of the curing profile of each encapsulant composition is different and various compositions can be designed to provide a curing profile suitable for a particular industrial manufacturing process.

  Solder balls 24 are embedded in the lower surface 202 of the substrate 20 in the outer region of the sealing material 25. The solder balls 24 may be made of any conductive metal that is commonly used to make electrical connections between the package and, for example, a circuit board.

  This package is particularly characterized by the absence of sealing material on the back and / or sides of the die. Therefore, no package molding is required.

  FIGS. 9A-9E are presented to further illustrate the present invention and show top views of the substrate in various stages prepared according to the method of one aspect of the present invention. FIG. 9A shows the front side surface 201 of the bare substrate 20. FIG. 9B shows the front side 201 of the substrate 20 after applying the adhesive 22. FIG. 9C shows the front side 201 of the substrate 20 with the adhesive 22 on the substrate after attaching the die 21. FIG. 9D shows the back side 202 of the substrate 20 after forming the wire bond 23 through the opening 200. FIG. 9E shows the back side 202 of the substrate 20 after the encapsulant 25 has been applied over the wire bond 23.

  Many modifications and variations of this invention can be made without departing from its concept and scope, as will be apparent to those skilled in the art. The specific embodiments described herein are provided by way of illustration only, and the invention is limited only by the terms of the appended claims, along with the full scope of equivalents to the claims that are entitled. The

Claims (16)

a) a substrate having an upper side, a lower side opposite to the upper side, an opening through the upper side and the lower side, and a wire bond pad on the lower side;
b) a semiconductor die having an active side having one or more conductive regions and a non-active side opposite the active side, the active side of the opening penetrating the upper and lower sides of the substrate A semiconductor die placed on a substrate, placed on top and completely covering the opening,
c) an adhesive disposed between and bonding the upper side of the substrate and the active side of the die, wherein the active side of the die is completely covered by the adhesive except for the conductive area;
d) a plurality of conductive bonding wires connecting the conductive area on the active side of the die to the wire bond pads on the lower side of the substrate through openings in the substrate;
e) a sealant applied on the lower surface of the substrate to seal the bonding wire and fill the opening in the substrate; and f) embedded on the lower surface with the substrate in the outer region of the sealant. A semiconductor package comprising a plurality of solder balls,
A semiconductor package characterized in that no encapsulant is present on the inactive side of the die and no encapsulant is present on the side of the die.   The package of claim 1, wherein the substrate is selected from the group consisting of BT and FR-4.   The package of claim 1, wherein the adhesive is selected from the group consisting of epoxy, bismaleimide, acrylate, siloxane, or combinations thereof. a) providing a substrate having an upper side, a lower side opposite the upper side, an opening through the upper side and the lower side, and a wire bond pad on the lower side;
b) providing at least one semiconductor die having an active side having one or more conductive regions and a non-active side opposite the active side;
c) After attaching the die to the substrate, the adhesive pattern on the upper side of the substrate so that the adhesive surrounds the opening and has at least the same size as the die footprint including the opening. Apply flowable adhesive with
d) optionally solidifying the flowable adhesive to a non-tacky state;
e) Place the die on the substrate, the active side is placed over the opening through the upper and lower sides of the substrate, completely covering the opening, and the conductive area on the active surface of the die is Exposed in the material openings, the active surface of the die is completely covered by the adhesive, except for the conductive areas,
f) optionally curing the adhesive;
g) attaching a plurality of conductive bonding wires and connecting the conductive area on the active side of the die through the opening in the substrate to a wire bond pad on the lower side of the substrate;
h) Applying a sealing material on the lower surface of the substrate, sealing the bonding wire, filling the opening of the substrate,
a method of manufacturing a semiconductor package comprising: i) curing the encapsulant; and j) embedding a plurality of solder balls on the lower surface of the substrate in an outer region of the encapsulant,
A method of manufacturing a semiconductor package, characterized in that there is no sealing step for the non-active side of the die and no sealing step for the side of the die.   The manufacturing method according to claim 4, wherein the adhesive is a printable paste.   The manufacturing method according to claim 4, wherein the base material does not have a mold stress releasing region.   The adhesive pattern includes a small void area around the conductive area including the wire bond pad, which is not coated with adhesive prior to die installation, and the adhesive flows into the die and substrate during die installation. The manufacturing method according to claim 4, wherein no gap is formed therebetween.   The manufacturing method according to claim 4, wherein the adhesive is B-staged before the die is placed on the substrate. a) providing a substrate having an upper side, a lower side opposite the upper side, an opening through the upper side and the lower side, and a wire bond pad on the lower side;
b) providing at least one semiconductor die having an active side having one or more conductive regions and a non-active side opposite the active side;
c) an adhesive pattern on the active side of the die so that the adhesive surrounds the opening and has at least the same size as the footprint of the die, including the opening, after attaching the die to the substrate. Apply the flowable adhesive,
d) optionally solidifying the flowable adhesive to a non-tacky state;
e) Place the die on the substrate, the active side is placed over the opening through the top and bottom sides of the substrate, completely covering the opening and conducting on the active surface of the die The area is exposed at the opening of the substrate so that the active surface of the die is completely covered by the adhesive, except for the conductive area,
f) optionally curing the adhesive;
g) attaching a plurality of conductive bonding wires and connecting the conductive area on the active side of the die through the opening in the substrate to a wire bond pad on the lower side of the substrate;
h) Applying a sealing material on the lower surface of the substrate, sealing the bonding wire, filling the opening of the substrate,
a method of manufacturing a semiconductor package comprising: i) curing the encapsulant; and j) embedding a plurality of solder balls on the lower surface of the substrate in an outer region of the encapsulant,
A method of manufacturing a semiconductor package, characterized in that there is no sealing step for the non-active side of the die and no sealing step for the side of the die.   The manufacturing method according to claim 9, wherein the adhesive is a printable paste.   The manufacturing method according to claim 9, wherein the base material has no mold stress release region.   The adhesive pattern includes a small void area around the conductive area including the wire bond pad, which is not coated with adhesive prior to die installation, and the adhesive flows into the die and substrate during die installation. The manufacturing method according to claim 9, wherein no gap is formed therebetween.   The manufacturing method according to claim 9, wherein the adhesive is B-staged before placing the die on the substrate.   The manufacturing method according to claim 9, wherein an adhesive is applied to the die before dicing the wafer.   The manufacturing method according to claim 9, wherein an adhesive is applied to the die after dicing the wafer.   A substrate for manufacturing a board-on-chip semiconductor package, comprising a front side, a back side opposite to the front side, and an opening penetrating the front side and the back side, wherein there is no mold stress release region A base material characterized by that.

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