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US20030016511A1 - Semiconductor device having a chip, reinforcing plate, and sealing material sharing a common rear surface - Google Patents

Semiconductor device having a chip, reinforcing plate, and sealing material sharing a common rear surface Download PDF

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Publication number
US20030016511A1
US20030016511A1 US10/252,710 US25271002A US2003016511A1 US 20030016511 A1 US20030016511 A1 US 20030016511A1 US 25271002 A US25271002 A US 25271002A US 2003016511 A1 US2003016511 A1 US 2003016511A1
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Prior art keywords
substrate
semiconductor
semiconductor device
semiconductor elements
chips
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US10/252,710
Inventor
Yoshihiro Tomita
Shinji Baba
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Renesas Technology Corp
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Mitsubishi Electric Corp
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Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to US10/252,710 priority Critical patent/US20030016511A1/en
Publication of US20030016511A1 publication Critical patent/US20030016511A1/en
Assigned to RENESAS TECHNOLOGY CORP. reassignment RENESAS TECHNOLOGY CORP. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MITSUBISHI DENKI KABUSHIKI KAISHA
Assigned to RENESAS TECHNOLOGY CORP. reassignment RENESAS TECHNOLOGY CORP. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MITSUBISHI DENKI KABUSHIKI KAISHA
Priority to US11/024,459 priority patent/US7094630B2/en
Abandoned legal-status Critical Current

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/31Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L24/32Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • HELECTRICITY
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    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/48Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
    • H01L23/488Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
    • H01L23/498Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
    • H01L23/49822Multilayer substrates
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    • H01L24/93Batch processes
    • H01L24/95Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L24/97Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
    • HELECTRICITY
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    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10Bump connectors; Manufacturing methods related thereto
    • H01L2224/15Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H01L2224/161Disposition
    • H01L2224/16151Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/16221Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/16225Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
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    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/27Manufacturing methods
    • H01L2224/27011Involving a permanent auxiliary member, i.e. a member which is left at least partly in the finished device, e.g. coating, dummy feature
    • H01L2224/27013Involving a permanent auxiliary member, i.e. a member which is left at least partly in the finished device, e.g. coating, dummy feature for holding or confining the layer connector, e.g. solder flow barrier
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321Disposition
    • H01L2224/32151Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/73Means for bonding being of different types provided for in two or more of groups H01L2224/10, H01L2224/18, H01L2224/26, H01L2224/34, H01L2224/42, H01L2224/50, H01L2224/63, H01L2224/71
    • H01L2224/732Location after the connecting process
    • H01L2224/73201Location after the connecting process on the same surface
    • H01L2224/73203Bump and layer connectors
    • H01L2224/73204Bump and layer connectors the bump connector being embedded into the layer connector
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/83009Pre-treatment of the layer connector or the bonding area
    • H01L2224/83051Forming additional members, e.g. dam structures
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    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/831Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector the layer connector being supplied to the parts to be connected in the bonding apparatus
    • H01L2224/83102Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector the layer connector being supplied to the parts to be connected in the bonding apparatus using surface energy, e.g. capillary forces
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/91Methods for connecting semiconductor or solid state bodies including different methods provided for in two or more of groups H01L2224/80 - H01L2224/90
    • H01L2224/92Specific sequence of method steps
    • H01L2224/921Connecting a surface with connectors of different types
    • H01L2224/9212Sequential connecting processes
    • H01L2224/92122Sequential connecting processes the first connecting process involving a bump connector
    • H01L2224/92125Sequential connecting processes the first connecting process involving a bump connector the second connecting process involving a layer connector
    • HELECTRICITY
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    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93Batch processes
    • H01L2224/95Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/97Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
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    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001Technical content checked by a classifier
    • H01L2924/00014Technical content checked by a classifier the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
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    • H01L2924/01004Beryllium [Be]
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    • H01L2924/01Chemical elements
    • H01L2924/01033Arsenic [As]
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    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
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    • H01L2924/01082Lead [Pb]
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    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151Die mounting substrate
    • H01L2924/1515Shape
    • H01L2924/15153Shape the die mounting substrate comprising a recess for hosting the device
    • HELECTRICITY
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    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151Die mounting substrate
    • H01L2924/1517Multilayer substrate
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    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/181Encapsulation
    • H01L2924/1815Shape
    • H01L2924/1816Exposing the passive side of the semiconductor or solid-state body
    • H01L2924/18161Exposing the passive side of the semiconductor or solid-state body of a flip chip

Definitions

  • the present invention relates to a semiconductor device which has a thin semiconductor element mounted thereon.
  • a thin semiconductor element having a thickness not greater than 0.1 mm for instance
  • a wafer is preliminarily ground to a thin one, the wafer is separated into independent chips by dicing, and the independent chips are mounted on substrates or lead frames in a usual method.
  • the usual method has created a problem in that a chip is likely to be fractured in handling, or that when a chip is mounted on a substrate, a stress is generated by bonding electrode portions to damage a coupling portion or the semiconductor element.
  • semiconductor device having a thin semiconductor element mounted thereon, the semiconductor element being obtained by mounting a plurality of semiconductor elements on a substrate, polishing rear surfaces of the semiconductor elements after sealing coupling portions, and separating the substrate with the semiconductor elements thereon into independent semiconductor devices.
  • a reinforcing plate is fixed on the substrate, and the substrate with the semiconductor elements thereon are separated into the independent semiconductor devices after assembly.
  • a reinforcing plate is fixed on the substrate, the reinforcing plate comprising a metallic plate and a wiring plate in layered fashion, and conduction is made between the wiring plate and wiring on the substrate.
  • a semiconductor device having thin semiconductors element mounted thereon, the semiconductor elements being obtained by mounting a plurality of semiconductor elements, sealing the semiconductor elements, providing a laminate on rear surfaces of the semiconductor elements to form a wiring layer with the semiconductor elements included therein after polishing the rear surfaces of the semiconductor elements, and wiring, followed by repeating the same step.
  • the plural semiconductor elements are mounted on a substrate, and the rear surfaces of the semiconductor elements are polished after sealing.
  • the semiconductor elements can be made thin without damaging the semiconductor elements.
  • the reinforcing plate is fixed on the substrate. Even if the substrate has low rigidity, the substrate can ensure required flatness, allowing polishing of the rear surfaces to be carried out with good precision.
  • the reinforcing plate is fixed on the substrate, and conduction is made between the wiring plate and the wiring on the substrate.
  • the semiconductor device can improve a wiring allowance for the substrate, can have a thin semiconductor element mounted thereon, and the semiconductor element can be made smaller.
  • semiconductor elements are mounted, the semiconductor elements are sealed, a wiring layer is provided by laminating after polishing rear surfaces of the semiconductor elements, and followed by the repeating the same step.
  • This arrangement can provide a semiconductor device with a plurality of chips mounted thereon in high density.
  • FIG. 1 is a cross-sectional side view showing the semiconductor device according to a first embodiment of the present invention
  • FIG. 2 is a fabrication flowchart for preparing the semiconductor device according to the first embodiment
  • FIG. 3 is a cross-sectional side view showing the semiconductor device according to a second embodiment of the present invention.
  • FIG. 4 is a fabrication flowchart for preparing the semiconductor device according to the second embodiment
  • FIG. 5 is a cross-sectional side view showing the semiconductor device according to a third embodiment of the present invention.
  • FIG. 6 is a cross-sectional view showing the semiconductor device according to a fourth embodiment of the present invention.
  • FIG. 7 is a fabrication flowchart for preparing the semiconductor device according to the fourth embodiment.
  • FIG. 1 a cross-sectional side view of the semiconductor device according to a first embodiment of the present invention.
  • reference numeral 1 designates a thin chip as a semiconductor element, which has been polished thin
  • reference numeral 2 designates a substrate
  • reference numeral 3 designates a bump, which couples the thin chip 1 and the substrate 2
  • reference numeral 4 designates a sealing resin
  • reference numeral 5 designates an external terminal provided on the substrate 2 .
  • FIG. 2 is shown an example of the fabrication flowchart for preparing the semiconductor device shown in FIG. 1.
  • a plurality of chips 1 are mounted on the substrate 2 (Step S 1 ), coupling portions between the substrate 2 and the chips 1 are sealed (Step S 2 ), and then the chips 1 have rear surfaces thereof collectively ground (Step S 3 ), and the substrate with the chips thereon is separated into independent semiconductor devices (Step S 4 ).
  • the rear surfaces of the chips 1 can be ground thin without damaging the chips 1 or the bumps 3 as the coupling portions.
  • the collective grinding of the rear surfaces can increase productivity.
  • FIG. 3 a cross-sectional side view of the semiconductor device according to a second embodiment of the present invention.
  • reference numeral 6 designates a reinforcing plate, which is fixed on the substrate 2 .
  • the other elements are the same as those of the first embodiment.
  • FIG. 4 is shown an example of the fabrication flowchart for preparing the semiconductor device according to the second embodiment.
  • a plurality of chips 1 are mounted on the substrate 2 , (Step S 11 ), reinforcing plates are fixed on the substrate (Step S 12 ), the coupling portions between the chips 1 and the substrate 2 are sealed (Step S 13 ), the chips 1 have rear surfaces thereof polished (Step S 14 ), and then the substrate 2 with the chips thereon are separated into independent semiconductor devices (Step S 15 ).
  • the semiconductor device and the fabrication method according to the second embodiment can ensure the flatness of the substrate and polish the rear surfaces of the chips with good precision even if the substrate has low rigidity.
  • FIG. 5 a cross-sectional side view of the semiconductor device according to a third embodiment of the present invention.
  • reference numeral 6 designates a reinforcing plate, which comprises a metallic plate 8 and wiring plates 7 in three-layered fashion.
  • Reference numeral 10 designates a wire for electrical conduction between the reinforcing plate 6 and the substrate 2 .
  • the reinforcing plate 6 has such a three-layered structure of the wiring plate 7 /the metallic plate 8 /the wiring plate 7 in the third embodiment, the layered structure or the order of the plates in the layered structure is not limited to the shown fashion.
  • the semiconductor device according to the third embodiment can improve the wiring allowance for the substrate and can have thin semiconductor elements mounted thereon in a smaller size.
  • FIG. 6 a cross-sectional side view of the semiconductor device according to a fourth embodiment of the present invention.
  • reference numeral 20 designates a wiring layer, which is layered on the substrate 2 , and which include chips 1 in plural sublayers.
  • Reference numerals 15 , 16 and 17 designate the respective wiring sublayers.
  • FIG. 7 is shown an example of the fabrication flowchart for preparing the semiconductor device according to the fourth embodiment.
  • the wiring layer 20 shown in FIG. 6 is prepared by coupling chips 1 (Steps S 21 and S 26 ), sealing (Step S 22 ), polishing the rear surfaces of the chips (Step S 23 ), providing a laminate on the rear surfaces (Step S 24 ), and wiring (Step S 25 ), repeating these steps, and finally separating the substrate with the wiring layer thereon into independent semiconductor devices as shown in the flowchart of FIG. 7.
  • the semiconductor device and the fabrication method according to the fourth embodiment can provide a semiconductor device with plural thin chips mounted thereon in high density.

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Dicing (AREA)

Abstract

A plurality of chips are mounted on a substrate, coupling portions between the chips and the substrate are sealed, the chips have rear surfaces thereof collectively polished, and the substrate with the chips thereon are separated into independent semiconductor devices.

Description

    FIELD OF THE INVENTION
  • The present invention relates to a semiconductor device which has a thin semiconductor element mounted thereon. [0001]
  • DISCUSSION OF BACKGROUND
  • When, in particular, a thin semiconductor element (having a thickness not greater than 0.1 mm for instance) is mounted on a conventional semiconductor device, a wafer is preliminarily ground to a thin one, the wafer is separated into independent chips by dicing, and the independent chips are mounted on substrates or lead frames in a usual method. [0002]
  • The usual method has created a problem in that a chip is likely to be fractured in handling, or that when a chip is mounted on a substrate, a stress is generated by bonding electrode portions to damage a coupling portion or the semiconductor element. [0003]
  • SUMMARY OF THE INVENTION
  • It is an object of the present invention to solve the problem, and provides a semiconductor device having a thin semiconductor element mounted thereon, the semiconductor element being obtained by mounting a plurality of chips on a substrate before thinning the thickness of the chips, and polishing rear surfaces of the chips with coupling portions protected by sealing after, e.g. testing or repairing or with a stress to the chips lessened. [0004]
  • According to a first aspect of the present invention, there is provided semiconductor device having a thin semiconductor element mounted thereon, the semiconductor element being obtained by mounting a plurality of semiconductor elements on a substrate, polishing rear surfaces of the semiconductor elements after sealing coupling portions, and separating the substrate with the semiconductor elements thereon into independent semiconductor devices. [0005]
  • According to a second aspect of the present invention, a reinforcing plate is fixed on the substrate, and the substrate with the semiconductor elements thereon are separated into the independent semiconductor devices after assembly. [0006]
  • According to a third aspect of the present invention, a reinforcing plate is fixed on the substrate, the reinforcing plate comprising a metallic plate and a wiring plate in layered fashion, and conduction is made between the wiring plate and wiring on the substrate. [0007]
  • According to a fourth aspect of the present invention, there is provided a semiconductor device having thin semiconductors element mounted thereon, the semiconductor elements being obtained by mounting a plurality of semiconductor elements, sealing the semiconductor elements, providing a laminate on rear surfaces of the semiconductor elements to form a wiring layer with the semiconductor elements included therein after polishing the rear surfaces of the semiconductor elements, and wiring, followed by repeating the same step. [0008]
  • The present invention is constructed as stated earlier, offering the following advantages. [0009]
  • In accordance with the first aspect, the plural semiconductor elements are mounted on a substrate, and the rear surfaces of the semiconductor elements are polished after sealing. As a result, the semiconductor elements can be made thin without damaging the semiconductor elements. [0010]
  • In accordance with the second aspect, the reinforcing plate is fixed on the substrate. Even if the substrate has low rigidity, the substrate can ensure required flatness, allowing polishing of the rear surfaces to be carried out with good precision. [0011]
  • In accordance with the third aspect, the reinforcing plate is fixed on the substrate, and conduction is made between the wiring plate and the wiring on the substrate. Thus, the semiconductor device can improve a wiring allowance for the substrate, can have a thin semiconductor element mounted thereon, and the semiconductor element can be made smaller. [0012]
  • In accordance with the fourth aspect, semiconductor elements are mounted, the semiconductor elements are sealed, a wiring layer is provided by laminating after polishing rear surfaces of the semiconductor elements, and followed by the repeating the same step. This arrangement can provide a semiconductor device with a plurality of chips mounted thereon in high density.[0013]
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: [0014]
  • FIG. 1 is a cross-sectional side view showing the semiconductor device according to a first embodiment of the present invention; [0015]
  • FIG. 2 is a fabrication flowchart for preparing the semiconductor device according to the first embodiment; [0016]
  • FIG. 3 is a cross-sectional side view showing the semiconductor device according to a second embodiment of the present invention; [0017]
  • FIG. 4 is a fabrication flowchart for preparing the semiconductor device according to the second embodiment; [0018]
  • FIG. 5 is a cross-sectional side view showing the semiconductor device according to a third embodiment of the present invention; [0019]
  • FIG. 6 is a cross-sectional view showing the semiconductor device according to a fourth embodiment of the present invention, and [0020]
  • FIG. 7 is a fabrication flowchart for preparing the semiconductor device according to the fourth embodiment.[0021]
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Now, preferred embodiments of the present invention will be described in detail, referring to FIGS. 1 through 7. [0022]
  • EMBODIMENT 1
  • In FIG. 1 is shown a cross-sectional side view of the semiconductor device according to a first embodiment of the present invention. In FIG. 1, [0023] reference numeral 1 designates a thin chip as a semiconductor element, which has been polished thin, reference numeral 2 designates a substrate, reference numeral 3 designates a bump, which couples the thin chip 1 and the substrate 2, reference numeral 4 designates a sealing resin, and reference numeral 5 designates an external terminal provided on the substrate 2.
  • In FIG. 2 is shown an example of the fabrication flowchart for preparing the semiconductor device shown in FIG. 1. As shown in FIG. 2, a plurality of [0024] chips 1 are mounted on the substrate 2 (Step S1), coupling portions between the substrate 2 and the chips 1 are sealed (Step S2), and then the chips 1 have rear surfaces thereof collectively ground (Step S3), and the substrate with the chips thereon is separated into independent semiconductor devices (Step S4).
  • As explained, in accordance with the semiconductor device and the fabrication method of the first embodiment, the rear surfaces of the [0025] chips 1 can be ground thin without damaging the chips 1 or the bumps 3 as the coupling portions. The collective grinding of the rear surfaces can increase productivity.
  • EMBODIMENT 2
  • In FIG. 3 is shown a cross-sectional side view of the semiconductor device according to a second embodiment of the present invention. In FIG. 3, [0026] reference numeral 6 designates a reinforcing plate, which is fixed on the substrate 2. The other elements are the same as those of the first embodiment.
  • In FIG. 4 is shown an example of the fabrication flowchart for preparing the semiconductor device according to the second embodiment. As shown in FIG. 4, a plurality of [0027] chips 1 are mounted on the substrate 2, (Step S11), reinforcing plates are fixed on the substrate (Step S12), the coupling portions between the chips 1 and the substrate 2 are sealed (Step S13), the chips 1 have rear surfaces thereof polished (Step S14), and then the substrate 2 with the chips thereon are separated into independent semiconductor devices (Step S15).
  • As explained, the semiconductor device and the fabrication method according to the second embodiment can ensure the flatness of the substrate and polish the rear surfaces of the chips with good precision even if the substrate has low rigidity. [0028]
  • EMBODIMENT 3
  • In FIG. 5 is shown a cross-sectional side view of the semiconductor device according to a third embodiment of the present invention. In FIG. 5, [0029] reference numeral 6 designates a reinforcing plate, which comprises a metallic plate 8 and wiring plates 7 in three-layered fashion. Reference numeral 10 designates a wire for electrical conduction between the reinforcing plate 6 and the substrate 2. Although the reinforcing plate 6 has such a three-layered structure of the wiring plate 7/the metallic plate 8/the wiring plate 7 in the third embodiment, the layered structure or the order of the plates in the layered structure is not limited to the shown fashion.
  • As explained, the semiconductor device according to the third embodiment can improve the wiring allowance for the substrate and can have thin semiconductor elements mounted thereon in a smaller size. [0030]
  • EMBODIMENT 4
  • In FIG. 6 is shown a cross-sectional side view of the semiconductor device according to a fourth embodiment of the present invention. In FIG. 6, [0031] reference numeral 20 designates a wiring layer, which is layered on the substrate 2, and which include chips 1 in plural sublayers. Reference numerals 15, 16 and 17 designate the respective wiring sublayers.
  • In FIG. 7 is shown an example of the fabrication flowchart for preparing the semiconductor device according to the fourth embodiment. The [0032] wiring layer 20 shown in FIG. 6 is prepared by coupling chips 1 (Steps S21 and S26), sealing (Step S22), polishing the rear surfaces of the chips (Step S23), providing a laminate on the rear surfaces (Step S24), and wiring (Step S25), repeating these steps, and finally separating the substrate with the wiring layer thereon into independent semiconductor devices as shown in the flowchart of FIG. 7.
  • As explained, the semiconductor device and the fabrication method according to the fourth embodiment can provide a semiconductor device with plural thin chips mounted thereon in high density. [0033]

Claims (4)

What is claimed is:
1. A semiconductor device having a thin semiconductor element mounted thereon, the semiconductor element being obtained by mounting a plurality of semiconductor elements on a substrate, polishing rear surfaces of the semiconductor elements after sealing coupling portions, and separating the substrate with the semiconductor elements thereon into independent semiconductor devices.
2. The semiconductor device according to claim 1, wherein a reinforcing plate is fixed on the substrate, and the substrate with the semiconductor elements thereon are separated into the independent semiconductor devices after assembly.
3. The semiconductor device according to claim 1, wherein a reinforcing plate is fixed on the substrate, the reinforcing plate comprising a metallic plate and a wiring plate in layered fashion, and conduction is made between the wiring plate and wiring on the substrate.
4. A semiconductor device having thin semiconductors element mounted thereon, the semiconductor elements being obtained by mounting a plurality of semiconductor elements, sealing the semiconductor elements, providing a laminate on rear surfaces of the semiconductor elements to form a wiring layer with the semiconductor elements included therein after polishing the rear surfaces of the semiconductor elements, and wiring, followed by repeating the same step.
US10/252,710 1999-10-27 2002-09-24 Semiconductor device having a chip, reinforcing plate, and sealing material sharing a common rear surface Abandoned US20030016511A1 (en)

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US11/024,459 US7094630B2 (en) 1999-10-27 2004-12-30 Method of fabricating semiconductor device having a chip, reinforcing plate, and sealing material sharing a common rear surface

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