US007012277B2
`
`(12) United States Patent
`Takenaka
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 7,012,277 B2
`Mar. 14, 2006
`
`(54) SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`6,645,783 B1 * 11/2003 Brunner et a1. ............. .. 438/26
`2004/0070338 A1
`4/2004 Noguchi et al.
`
`(75) Inventor: Yasuji Takenaka, Nara (JP)
`
`(73) Assignee: Sharp Kabushiki Kaisha, Osaka (JP)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 31 days.
`
`(21) Appl. No.: 10/745,764
`
`(22) Filed:
`
`Dec. 23, 2003
`
`(65)
`
`(30)
`
`Prior Publication Data
`
`US 2004/0135156 A1
`
`Jul. 15, 2004
`
`Foreign Application Priority Data
`
`Jan. 6, 2003
`
`(JP)
`
`........................... .. 2003-000216
`
`(51) Int. Cl.
`(2006.01)
`H01L 29/26
`(52) US. Cl. ......................................... .. 257/79; 257/80
`(58) Field of Classi?cation Search ................ .. 257/79,
`257/80, 81, 88, 93, 98
`See application ?le for complete search history.
`
`(56)
`
`References Cited
`
`US. PATENT DOCUMENTS
`
`FOREIGN PATENT DOCUMENTS
`
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`
`11-046018
`2000-058924
`2000-077725
`2000-124566
`2000-216443
`2002-222998
`2003-078219
`
`2/1999
`2/2000
`3/2000
`4/2000
`8/2000
`8/2002
`3/2003
`
`* cited by examiner
`
`Primary Examiner—David Nelms
`Assistant Examiner—Thinh T Nguyen
`(74) Attorney, Agent, or Firm—Morrison & Foerster LLP
`
`(57)
`
`ABSTRACT
`
`A semiconductor light emitting device includes an LED
`chip, a ?rst lead frame on Which the LED chip is mounted,
`a second lead frame electrically connected to the LED chip
`via a bonding Wire, and a resin portion surrounding the
`circumference of the LED chip, and fastening the ?rst and
`second lead frames. Ametal body is located under the region
`of the ?rst lead frame Where the LED chip is mounted.
`
`6,335,548 B1 *
`
`1/2002 Roberts et al. ............. .. 257/98
`
`9 Claims, 4 Drawing Sheets
`
`7/1/1111!
`
`2 Q / III/[Illa
`
`‘Am/1111111111
`‘ ‘
`
`Cree Ex. 1009
`
`Page 1
`
`

`

`US. Patent
`
`Mar. 14, 2006
`
`Sheet 1 0f4
`
`US 7,012,277 B2
`
`FIG.1
`
`W}!W\
`
`
`
`
`
`VIII/IIIIIIIIIIII\I.WIL_IIIII\IIIIIIIIII2
`fl3
`‘i\\\\\\‘.‘\\K‘:
`
`
`
`
`[III/III],
`‘IIIIIIIIA L L
`
`
`
`FIG.2
`
`\\\ \\\\\§
`E§7;
`
`V
`
`FIG.3
`
`
`
` :1
`KW71“:
`
`{II/IIIIIIIIIIIIII.IIII/IIIIIIIIIIIIII:
`
`
`
`
`Cree Ex. 1009
`
`Page 2
`
`Cree Ex. 1009
`
`Page 2
`
`

`

`US. Patent
`
`Mar. 14, 2006
`
`Sheet 2 0f4
`
`US 7,012,277 B2
`
`6
`
`
`
`
`’ ‘|;I({II_IIIIIIIIIII//’
`‘
`a
`a
`,2
`VIII/II
`
`-
`
`8
`
`Cree Ex. 1009
`
`Page 3
`
`
`at». I:
`
`
`,
`
`‘
`
`.
`
`
`V
`[II/IIIIIIIA '
`
`a
`‘—
`
`a \
`4
`n
`III/IIIIA
`
`
`
`
`Cree Ex. 1009
`
`Page 3
`
`

`

`U.S. Patent
`
`Mar. 14, 2006
`
`Sheet 3 of4
`
`US 7,012,277 B2
`
`FIG.6A
`
`\ W \ \\\\\\\\\“\\\
`
`FIG.6B
`
`Cree Ex. 1009
`
`Page 4
`
`

`

`US. Patent
`
`Mar. 14, 2006
`
`Sheet 4 0f4
`
`US 7,012,277 B2
`
`
`
`“““““‘ ““ .““‘\\‘“‘“\‘\‘
`
`
`
`
`
`fi"
`'S
`
`
`
`
`
`
`10
`
`“““““‘“““ It“\“‘“‘\“‘\“‘_
`
`
`
`
`\38/////\
`
`
`
`
`10
`
`
`
`f\\\\\\‘
`
`
`[III/III].
`
`
`VIII/[Ill
`
`Cree Ex. 1009
`
`Page 5
`
`Cree Ex. 1009
`
`Page 5
`
`

`

`US 7,012,277 B2
`
`1
`SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`The present invention relates to a semiconductor light
`emitting device and a fabrication method thereof. Particu
`larly, the present invention relates to a semiconductor light
`emitting device employing a light emitting element such as
`a light emitting diode (LED), and a fabrication method
`thereof.
`2. Description of the Background Art
`An example of a conventional semiconductor light emit
`ting device is shoWn in FIG. 8.
`Referring to FIG. 8, a resin portion 3 is formed by
`insert-molding in a manner With a ?rst lead frame 1 and a
`second lead frame 2 secured. An LED chip 4 is mounted on
`?rst lead frame 1 With Ag paste 7. A bonding Wire 5 is
`attached to second lead frame 2. LED chip 4 is surrounded
`by epoxy resin 6 to be protected and sealed.
`A fabrication method of the semiconductor light emitting
`device of FIG. 8 Will be described hereinafter.
`First and second lead frames 1 and 2 are formed in a
`predetermined pattern con?guration, and embedded in resin
`portion 3 by insert-molding With the coat of bonding Ag
`applied. Then, LED chip 4 is mounted on ?rst lead frame 1
`With Ag paste 7. Bonding Wire 5 is attached to second lead
`frame 2. Thus, electrical and mechanical connection of the
`lead frame is established. Sealing is provided by epoxy resin
`6. Since the surface of the lead frame Will be covered With
`rust to impede soldering if the surface is left With the Ag
`coat, an outer coat such as a solder coat is applied on the lead
`frame region. Then, unnecessary regions of the lead frame
`are cut aWay. The lead frame is bent to take the shape of a
`rigid-angle bent C form, and a terminal for junction With the
`mounting board is formed.
`Heat is generated When light is emitted from the mounted
`LED chip. The generated amount of heat is proportional to
`the current ?oWing through the LED chip. The light emitting
`ef?ciency of the LED chip becomes loWer as the temperature
`of the LED chip becomes higher, leading to degradation of
`light. In other Words, brighter light cannot be effectively
`achieved even if a large current is conducted, and the
`lifetime of the LED chip Will become shorter.
`An LED chip exhibiting favorable light emitting ef?
`ciency even under high current and With favorable lifetime
`property can be provided by discharging the heat generated
`from the LED chip ef?ciently outside to reduce the tem
`perature of the LED chip.
`Such a conventional semiconductor light emitting device
`aimed to improve heat radiation ef?ciency is disclosed in,
`for example, Japanese Patent Laying-Open No. 11-46018
`(Conventional Example 1), Japanese Patent Laying-Open
`No. 2002-222998 (Conventional Example 2), Japanese
`Patent Laying-Open No. 2000-58924 (Conventional
`Example 3), Japanese Patent Laying-Open No. 2000-77725
`(Conventional Example 4), and Japanese Patent Laying
`Open No. 2000-216443 (Conventional Example 5).
`In Conventional Examples 1 and 2, heat radiation is
`improved by increasing the surface area of the lead frame.
`In Conventional Examples 3, 4 and 5, heat radiation is
`improved by using metal having thermal conductivity
`greater than that of resin for the substrate material.
`HoWever, increasing the surface area of the lead frame at
`the LED side by taking a nonlinear con?guration for the lead
`frame or increasing the thickness as in Conventional
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`55
`
`60
`
`65
`
`2
`Examples 1 and 2 is relatively limited by the restricted siZe
`of the package. The surface area of the lead frame cannot be
`increased sufficiently by just altering the con?guration.
`Thus, the heat radiation ef?ciency could not be improved to
`a sufficient level.
`Since the lead frame is to be bent at a subsequent step, the
`lead frame cannot be made too thick. Furthermore, a thicker
`lead frame Will require greater force in punching out the lead
`frame from the sheet member, as compared to a thinner
`frame. Accordingly, the thickness of the mold must be
`increased to ensure the strength of the mold, leading to a
`Wider gap of the punching part, i.e., betWeen lead frames.
`Generally a gap equal to the thickness of the lead frame, or
`at least % the thickness of the lead frame, is required. If the
`gap betWeen lead frames is increased, suf?cient area for
`bonding cannot be provided, or the frame area Will become
`smaller.
`Another approach related to heat radiation ef?ciency is to
`increase the contacting area betWeen the lead frame terminal
`on the part of the LED element and the mounting board.
`Although this is advantageous from the standpoint of heat
`radiation, the heat during soldering Will be easily conducted
`to the LED device to adversely affect the reliability.
`In the case Where metal having higher thermal conduc
`tivity than resin is employed for the substrate as in Conven
`tional Examples 3, 4 and 5, there is a possibility of the heat
`during soldering adversely affecting the reliability of the
`LED device, likeWise the above-described case.
`
`SUMMARY OF THE INVENTION
`
`In vieW of the foregoing, an object of the present inven
`tion is to provide a semiconductor light emitting device
`exhibiting high heat radiation and favorable light emitting
`ef?ciency and lifetime property Without degrading the lead
`frame Workability and the reliability of the LED chip, and a
`fabrication method thereof.
`According to an aspect of the present invention, a semi
`conductor light emitting device includes an LED chip, a ?rst
`lead frame on Which the LED chip is mounted, a second lead
`frame electrically connected to the LED chip via a Wire, and
`a resin portion surrounding the LED chip and securing the
`?rst and second lead frames. A metal body is located under
`the region of the ?rst lead frame Where the LED chip is
`mounted.
`Accordingly, heat can be transmitted ef?ciently from the
`?rst lead frame to the metal body. Thus, a semiconductor
`light emitting device exhibiting superior heat radiation can
`be provided.
`The metal body may be located apart from the ?rst lead
`frame or brought into contact With the ?rst lead frame. In
`both cases, electrical insulation of the lead frame is estab
`lished.
`In the case Where the surface of the metal body is
`subjected to an electrical insulation process, the surface of
`the metal body subjected to the insulation process preferably
`forms contact With the ?rst lead frame. Accordingly, heat
`radiation of the semiconductor light emitting device can be
`further improved.
`The semiconductor light emitting device preferably
`includes a plurality of LED chips. Accordingly, the appli
`cability to a product such as a full color display can be
`increased.
`According to another aspect of the present invention, a
`semiconductor light emitting device includes an LED chip,
`a metal body on Which the LED chip is mounted, a ?rst lead
`frame electrically connected to the metal body, a second lead
`
`Cree Ex. 1009
`
`Page 6
`
`

`

`US 7,012,277 B2
`
`3
`frame electrical connected to the LED chip via a Wire, and
`a resin portion surrounding the metal body and the LED
`chip, and securing the ?rst and second lead frames.
`Accordingly, the heat generated at the LED chip is
`directly transmitted to the mounting board via the metal
`body. Thus, heat radiation is improved.
`Preferably, the top portion of the metal body is formed in
`an upside doWn conical-frustum con?guration, and the top
`portion is ?tted in the ?rst lead frame. Accordingly, the metal
`body is ?rmly secured to the lead frame. By the effect of
`re?ection of the upside doWn conical-frustum con?guration,
`the luminous intensity of the semiconductor light emitting
`device can be improved.
`In the semiconductor light emitting device set forth
`above, the metal body preferably includes at least one
`material selected from the group consisting of copper,
`aluminum, copper alloy and aluminum alloy. These metals
`are advantageous in that the heat radiation of the semicon
`ductor light emitting device can be improved by virtue of the
`high heat radiation.
`According to an aspect of a fabrication method of a
`semiconductor light emitting device of the present inven
`tion, the fabrication method includes the steps of forming,
`by insert-molding, a resin portion holding a metal body and
`?rst and second lead frames, and mounting an LED chip on
`the metal body or ?rst lead frame. Accordingly, the heat
`generated at the LED chip can be transmitted to the mount
`ing board via the metal body located under the region of the
`?rst lead frame Where the LED chip is mounted. A semi
`conductor light emitting device superior in heat radiation
`can be provided.
`According to a still further aspect of the present invention,
`a fabrication method of a semiconductor light emitting
`device of the present invention includes the steps of forming,
`by insert-molding, a resin portion holding the ?rst and
`second lead frames, and having a concave, attaching a metal
`body to the concave, and mounting an LED chip on the
`metal body or the ?rst lead frame.
`The fabrication method of a semiconductor light emitting
`device set forth above further includes the step of caulking
`the metal body and the ?rst lead frame. Preferably, the top
`portion of the metal body is Worked to an upside doWn
`conical-frustum con?guration simultaneous to the caulking
`step. By the caulking step, the metal body and the ?rst lead
`frame are secured more ?rmly. Also, the luminous intensity
`of the semiconductor light emitting device can be improved
`by the effect of the re?ection of the upside doWn conical
`frustum con?guration.
`According to the semiconductor light emitting device and
`fabrication method of the present invention, the heat gen
`erated at the LED chip can be discharged toWards the
`mounting board via the metal body located under the region
`of the ?rst lead frame Where the LED chip is mounted. It is
`not necessary to use a thick lead frame. Therefore, degra
`dation of the Workability of the lead frame can be prevented.
`Furthermore, the heat during soldering Will not be easily
`transmitted to the LED. Thus, a semiconductor light emit
`ting device superior in heat radiation can be provided
`Without degrading the Workability of the lead frame and
`reliability of the LED chip.
`The foregoing and other objects, features, aspects and
`advantages of the present invention Will become more
`apparent from the folloWing detailed description of the
`present invention When taken in conjunction With the
`accompanying drawings.
`
`4
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`10
`
`15
`
`FIGS. 1—5 are sectional vieWs of a surface mount type
`LED according to ?rst, second, third, fourth, and ?fth
`embodiments, respectively, of the present invention.
`FIGS. 6A and 6B represent a fabrication method of a
`substrate on Which an LED is mounted according to a siXth
`embodiment, Wherein FIG. 6A corresponds to the case
`Where the lead frame and metal body are set in an insert
`molding die and FIG. 6B shoWs a resin portion after
`insert-molding of the lead frame and metal body is com
`pleted.
`FIGS. 7A, 7B and 7C represent a fabrication method of a
`substrate on Which an LED is mounted according to a
`seventh embodiment of the present invention, Wherein FIG.
`7A corresponds to the case Where the lead frame is set in an
`insert-molding die, FIG. 7B shoWs a resin portion after
`insert-molding of the lead frame, and FIG. 7C corresponds
`to the case Where the metal body is inserted in the concave
`of the resin portion.
`FIG. 8 is a sectional vieW of an eXample of a conventional
`semiconductor light emitting device.
`
`25
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`Embodiments of a semiconductor light emitting device
`and fabrication method thereof Will be described hereinafter.
`First, embodiments of the inventive semiconductor light
`emitting device Will be described With reference to FIGS.
`1—5.
`In the ?rst to ?fth embodiments set forth beloW, the
`number of LED chips 4 mounted is preferably in plurality.
`Accordingly, applicability of the semiconductor light emit
`ting device to a product such as a full color display can be
`increased. In the case Where a plurality of LED chips are
`mounted in one product, heat radiation is critical due to the
`large heat generation. The present embodiment is particu
`larly advantageous to overcome this problem.
`First Embodiment
`FIG. 1 is a sectional vieW of a surface mount type LED
`according to a ?rst embodiment of the present invention.
`The semiconductor light emitting device of the ?rst
`embodiment includes an LED chip 4, a ?rst lead frame 1 on
`Which LED chip 4 is mounted, a second lead frame 2
`electrically connected to LED chip 4 via a bonding Wire 5
`such as a gold Wire, and a resin portion 3 surrounding the
`circumference of LED chip 4, and securing the lead frame.
`Ametal body 8 is located under the region of ?rst lead frame
`1 Where LED chip 4 is mounted.
`First and second lead frames 1 and 2 are embedded in
`resin portion 3 by insert-molding. LED chip 4 is mounted on
`?rst lead frame 1 With Ag paste 7 therebetWeen. Bonding
`Wire 5 is attached to second lead frame 2. Accordingly,
`second lead frame 2 is mechanically and electrically con
`nected to LED chip 4. Resin portion 3 is formed so as to
`surround the circumference of LED chip 4, bonding Wire 5,
`and Ag paste 7. The inner side surrounded by resin portion
`3 is sealed With epoXy resin 6 to protect the LED element
`portion.
`Metal body 8 is held by resin portion 3 functioning as a
`substrate. The loWer portion of metal body 8 is eXposed at
`resin portion 3 so as to be in close proximity to or formed
`in contact With the mounting board. Metal block 8 takes a
`block form, and is sandWiched betWeen ?rst and second lead
`frames 1 and 3 via resin portion 3.
`
`35
`
`40
`
`45
`
`55
`
`65
`
`Cree Ex. 1009
`
`Page 7
`
`

`

`US 7,012,277 B2
`
`5
`In the ?rst embodiment, metal body 8 is preferably
`located apart from ?rst and second lead frames 1 and 2.
`The reason Why a gap is provided betWeen ?rst and
`second lead frames 1 and 2 and metal body 8 is to prevent
`the patterns of ?rst and second lead frames 1 and 2 formed
`in separation from short-circuiting due to contact therebe
`tWeen. In the ?rst embodiment, the heat generated from LED
`chip 4 is sequentially transmitted through the ?rst lead frame
`1, the gap betWeen ?rst lead frame 1 and metal body 8, and
`then to metal body 8 to be discharged toWards the mounting
`board. In order to efficiently transmit the heat generated at
`LED chip 4 to metal body 8, the aforementioned gap is
`preferably as small as possible. Also preferably, the volume
`of metal body 8 in the package is as large as possible in the
`package.
`Preferably, metal body 8 includes at least one material
`selected from the group consisting of copper, aluminum,
`copper alloy and aluminum alloy. This is preferable from the
`standpoint of improving heat radiation due to the high heat
`radiation of these metal. The material of metal body 8 is not
`limited to those cited above, and other metal as Well as a
`material other than metal such as ceramic may be used as
`long as it has a high heat radiation. It is to be noted that
`ceramic, though inferior in thermal conductivity than metal
`material, is insulative. Therefore, in the case Where ceramic
`is employed, the ceramic body corresponding to metal body
`8 can be brought into contact With ?rst and second lead
`frames 1 and 2 Without having to apply an insulation process
`on the surface.
`Resin portion 3 located around LED chip 4 is formed of
`White resin having high re?ectance for the purpose of
`re?ecting ef?ciently the light emitted from LED chip 4.
`Furthermore, to promote output to the front side ef?ciently,
`the inner circumferential face is formed to take an upside
`doWn conical-frustum con?guration. In the semiconductor
`light emitting device of the ?rst embodiment, resin superior
`in heat resistance is employed for resin portion 3 since the
`semiconductor light emitting device is to be delivered to
`subsequent processing as a surface mount component. Spe
`ci?cally, liquid crystal polymer, polyamide type resin, and
`the like satisfying the above-described requirement is used.
`In the case Where a large area of light emission is required,
`the inner circumferential face of resin portion 3 may take a
`con?guration other than the upside doWn conical-frustum
`con?guration, such as an upside doWn frustum con?guration
`of a pyramid.
`Epoxy resin 6 serves to protect the LED element portion.
`Epoxy resin 6 is transparent or lacteous, and is introduced
`mainly by potting. Alternatively, transfer-molding, injec
`tion-molding, and the like may be employed. In this case, the
`light emitting portion can take an arbitrary con?guration
`(lens shape, or the like).
`In the ?rst embodiment, metal body 8 is located in the
`neighborhood of the center, When vieWed in plane, of resin
`portion 3, and Will not directly encounter the heat generated
`during the soldering step toWards the mounting board. Thus,
`the heat generated during soldering Will not degrade the
`reliability of the LED chip.
`In vieW of the foregoing, the semiconductor light emitting
`device of the ?rst embodiment is advantageous over con
`ventional semiconductor light emitting devices in that heat
`radiation can be improved more easily.
`Second Embodiment
`FIG. 2 is a sectional vieW of a surface mount type LED
`according to a second embodiment of the present invention.
`The semiconductor light emitting device of the second
`embodiment is a modi?cation of the semiconductor light
`emitting device of the ?rst embodiment. Metal body 8 is
`brought into contact With ?rst lead frame 1.
`
`15
`
`25
`
`35
`
`40
`
`45
`
`55
`
`65
`
`6
`For example, ?rst lead frame 1 on Which LED chip 4 is
`mounted is set loWer than second lead frame 2, Whereby
`contact With metal body 8 is established. In the example
`shoWn in FIG. 2, ?rst lead frame 1 is bent to form contact
`With metal body 8.
`Accordingly, the heat generated from LED chip 4 is
`sequentially transmitted through ?rst lead frame 1, metal
`body 8, and the mounting board. The gap betWeen ?rst lead
`frame 1 and metal body 8 seen in the ?rst embodiment is
`absent, so that the heat generated at LED chip 4 can be
`transmitted to the mounting board more effectively.
`Although ?rst lead frame 1 is bent doWn to form contact
`With metal body 8 in the present embodiment, a similar
`object can be effected by altering the shape of metal body 8
`instead of modifying ?rst lead frame 1. For example, a
`protrusion at the top plane of metal body 8 may be formed.
`In vieW of the foregoing, the semiconductor light emitting
`device of the present embodiment can be improved in heat
`radiation as compared to the semiconductor light emitting
`device of the ?rst embodiment.
`Third Embodiment
`FIG. 3 is a sectional vieW of a surface mount type LED
`according to a third embodiment.
`The semiconductor light emitting device of the third
`embodiment is another modi?cation of the semiconductor
`light emitting device of the ?rst embodiment. An electrical
`insulative processed portion 9 by, for example, applying an
`insulating ?lm, an insulating coat, or by anodiZation, is
`provided at the surface of metal body 8. The surface of metal
`body 8 subjected to an insulating process forms contact With
`?rst and second lead frames 1 and 2.
`In the semiconductor light emitting device of the second
`embodiment, the heat generated from LED chip 4, either in
`the case of a single LED chip or a plurality of LED chips,
`can be transmitted to the mounting board, absent of the
`portion corresponding to the gap betWeen ?rst lead frame 1
`and metal body 8 as in the ?rst embodiment, as long as the
`LED chips are located on the same lead frame.
`In the case Where a plurality of LED chips 4 are located
`on different lead frames, only one of the lead frames can be
`brought into contact With metal body 8 in order to prevent
`the patterns of respective lead frames formed in separation
`from short-circuiting. This means that a pattern portion
`restricted in heat radiation improvement Will be present.
`The third embodiment directed to the same object as the
`second embodiment is characteriZed in that short-circuiting
`Will not occur even if the pattern of all lead frames is brought
`into contact With metal body 8 by virtue of the provision of
`an electrical insulative processed portion 9 at metal body 8.
`All the pattern portions can exhibit heat radiation ef?ciency.
`The present third embodiment is advantageous in that heat
`radiation can be improved readily even When a plurality of
`LED chips 4 are located on different lead frames. The heat
`generated from LED chip 4 can be transmitted to the
`mounting board via the second lead frame 2, in addition to
`the transmitting route of ?rst lead frame 1, metal body 8, and
`the mounting board.
`Fourth Embodiment
`FIG. 4 is a sectional vieW of a surface mount type LED
`according to a fourth embodiment of the present invention.
`The semiconductor light emitting device of the fourth
`embodiment includes an LED chip 4, a metal body 8 on
`Which LED chip 4 is mounted, a ?rst lead frame 1 electri
`cally connected to metal body 8, a second lead frame 2
`electrically connected to LED chip 4 via bonding Wire 5, and
`a resin portion 3 surrounding the circumference of metal
`body 8 and LED chip 4, and fastening the ?rst and second
`lead frames.
`The fourth embodiment is characteriZed in that LED chip
`4 is directly mounted on metal body 8. The heat generated
`
`Cree Ex. 1009
`
`Page 8
`
`

`

`US 7,012,277 B2
`
`7
`from LED chip 4 is directly transmitted to metal body 8 to
`be transferred to the mounting board via metal body 8.
`Therefore, heat can be radiated more ef?ciently than in the
`?rst to third embodiments.
`Fifth Embodiment
`FIG. 5 is a sectional vieW of a surface mount type LED
`according to a ?fth embodiment of the present invention.
`In the ?fth embodiment, the top portion of metal body 8
`is formed to have an upside doWn conical-frustum con?gu
`ration. The top portion of metal body 8 is ?tted in ?rst lead
`frame 1. Metal body 8 and ?rst lead frame 1 are integrated
`as one piece by caulking. The top portion of metal body 8 is
`formed in an upside doWn conical-frustum con?guration
`simultaneous to the caulking step. Accordingly, metal body
`8 and ?rst lead frame 1 are ?rmly secured. Furthermore, the
`luminous intensity of the semiconductor light emitting
`device can be increased by the re?ection effect of the upside
`doWn conical-frustum con?guration. The con?guration of
`the top portion of metal body 8 is not limited to the
`aforementioned upside doWn conical-frustum con?guration.
`For eXample, an upside doWn frustum con?guration of a
`pyramid can be employed.
`Sixth and seventh embodiments related to securing metal
`body 8 to resin portion 3 Will be described With reference to
`FIGS. 6A and 6B and FIGS. 7A, 7B and 7C.
`Sixth Embodiment
`FIGS. 6A and 6B represent a fabrication method of a
`substrate on Which an LED is mounted according to the siXth
`embodiment.
`The fabrication method of the present siXth embodiment
`includes the step of forming, by insert molding, a resin
`portion 3 holding a metal body 8 and a lead frame 10, and
`the step of mounting an LED chip 4 on metal body 8 or lead
`frame 10. FIGS. 6A and 6B correspond to the case Where
`LED chip 4 is mounted on lead frame 10.
`As shoWn in FIG. 6A, lead frame 10 and metal body 8 are
`set substantially at the same time in an insert-molding die 11
`for insert-molding. Accordingly, resin portion 3 is formed so
`as to integrate lead frame 10 With metal body 8, as shoWn in
`FIG. 6B. Then, LED chip 4 is mounted on one lead frame
`With Ag paste. LED chip 4 is connected to the other lead
`frame via a bonding Wire.
`Seventh Embodiment
`FIGS. 7A, 7B and 7C represent a fabrication method of a
`substrate on Which an LED is mounted according to a
`seventh embodiment of the present invention.
`The fabrication method of the seventh embodiment
`includes the steps of forming resin portion 3 having a
`concave 13 by insert-molding so as to hold the frame 10,
`attaching metal body 8 to concave 13, and mounting LED
`chip 4 on metal body 8 or lead frame 10.
`As shoWn in FIG. 7A, lead frame 10 is set in an insert
`molding die 11 having a metal body insertion region for
`mation die 12 for insert-molding. Accordingly, resin portion
`3 holding lead frame 10 and having concave 13 can be
`formed as shoWn in FIG. 7B. Referring to FIG. 7C, metal
`body 8 is inserted into concave 13 in resin portion 3
`subjected to the molding step set forth above, and ?rmly
`?Xed using an adhesive or the like. Through a subsequent
`step similar to that of the siXth embodiment, LED chip 4 is
`mounted on one lead frame. LED chip 4 is connected to the
`other lead frame via bonding Wire.
`Although the present invention has been described and
`illustrated in detail, it is clearly understood that the same is
`by Way of illustration and eXample only and is not to be
`taken by Way of limitation, the spirit and scope of the present
`invention being limited only by the terms of the appended
`claims.
`
`10
`
`15
`
`25
`
`35
`
`40
`
`45
`
`55
`
`65
`
`8
`
`What is claimed is:
`1. A semiconductor light emitting device comprising:
`an LED chip,
`a ?rst lead frame on Which said LED chip is mounted,
`a second lead frame electrically connected to said LED
`chip via a Wire, and
`a resin portion surrounding a circumference of said LED
`chip, and fastening said ?rst and second lead frames,
`Wherein a metal body is located under a region of said ?rst
`lead frame Where said LED chip is mounted, and
`Wherein the second lead frame has a portion Where the
`Wire is connected and the metal body is provided to
`eXtend to a region beloW said portion of the second lead
`frame.
`2. The semiconductor light emitting device according to
`claim 1, Wherein said metal body is spaced apart from said
`?rst and second lead frames.
`3. The semiconductor light emitting device according to
`claim 1, Wherein said metal body forms thermal and elec
`trical contact With said ?rst lead frame.
`4. The semiconductor light emitting device according to
`claim 1, Wherein
`said metal body has a surface subjected to an electrical
`insulating process, and
`said surface of said metal body subjected to said electrical
`insulating process forms physical contact With said ?rst
`lead frame.
`5. The semiconductor light emitting device according to
`claim 1, comprising a plurality of LED chips.
`6. The semiconductor light emitting device according to
`claim 1, Wherein said metal body includes at least one type
`of material selected from the group consisting of copper,
`aluminum, copper alloy, and aluminum alloy.
`7. A semiconductor light emitting device comprising:
`an LED chip,
`a metal body on Which said LED chip is mounted,
`a ?rst lead frame electrically connected to said metal
`body,
`a second lead frame electrically connected to said LED
`chip via a Wire, and
`a resin portion surrounding a circumference of said metal
`body and said LED chip, and fastening said ?rst and
`second lead frames, and
`Wherein the second lead frame has a portion Where the
`Wire is connected and the metal body is provided to
`eXtend to a region beloW said portion of the second lead
`frame.
`8. A semiconductor light emitting device comprising:
`an LED chip,
`a metal body on Which said LED chip is mounted,
`a ?rst lead frame electrically connected to said metal
`body,
`a second lead frame electrically connected to said LED
`chip via a Wire, and
`a resin portion surrounding a circumference of said metal
`body and said LED chip, and fastening said ?rst and
`second lead frames.
`Wherein
`said metal body has a top portion Worked in an upside
`doWn conical-frustum con?guration, and
`said top portion is ?tted in said ?rst lead frame.
`9. The semiconductor light emitting device according to
`claim 7, Wherein said metal body includes at least one type
`of material selected from the group consisting of copper,
`aluminum, copper alloy, and aluminum alloy.
`
`*
`
`*
`
`*
`
`*
`
`*
`
`Cree Ex. 1009
`
`Page 9
`
`