US007282740B2
`
`(12) United States Patent
`US 7,282,740 B2
`(10) Patent No.:
`(45) Date of Patent:
`Oct. 16, 2007
`Chikugawa et al.
`
`(54) SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`(75)
`
`Inventors: Hiroshi Chikugawa, Kashihara (JP);
`Yoshihiko Yamamoto, Yamatokoriyama
`(JP); Eiji Kametani, Yamatotakada (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 0 days.
`
`(21) Appl. No.: 11/013,617
`
`(22)
`
`Filed:
`
`Dec. 15, 2004
`
`(65)
`
`Prior Publication Data
`
`3/2002 Ishinaga ...................... 257/98
`6,355,946 B1*
`4/2002 Arndt
`............
`257/678
`6,376,902 B1*
`
`...... 257/684
`6,486,543 B1* 11/2002 Sano et al.
`
`6,603,148 B1*
`8/2003 Sano et al.
`........ 257/98
`
`................... 257/99
`2002/0190262 A1* 12/2002 Nitta et al.
`2003/0116769 A1
`6/2003 Song et al.
`2003/0168720 A1*
`9/2003 Kamada ..................... 257/666
`2004/0188719 A1*
`9/2004 Nawashiro et al.
`......... 257/200
`
`FOREIGN PATENT DOCUMENTS
`
`JP
`JP
`JP
`
`2002-176203
`2003-115615
`2003-197974
`
`6/2002
`4/2003
`7/2003
`
`* cited by examiner
`
`Primary Examiner7Zandra V. Smith
`Assistant ExamineriTsz Chiu
`
`US 2005/0133939 A1
`
`Jun. 23, 2005
`
`(74) Attorney, Agent, or FirmiMorrison & Foerster, LLP
`
`(30)
`
`Foreign Application Priority Data
`
`(57)
`
`ABSTRACT
`
`Dec. 17, 2003
`
`(JP)
`
`............................. 2003-419585
`
`(51)
`
`Int. Cl.
`(2006.01)
`H01L 27/15
`(52) US. Cl.
`............................ 257/79; 257/13; 257/98;
`257/99; 257/103; 257/433; 257/434; 257/704
`(58) Field of Classification Search .................. 257/98,
`257/790, 13, 99, 103, 433, 434, 704
`See application file for complete search history.
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`A light emitting element is die-bonded to a portion of a lead
`frame exposed at the bottom of an opening formed at a top
`face of a resin package. A reflector to direct light emitted
`from the light emitting element towards a predetermined
`direction is attached to the top face of the resin package.
`Lead terminals are arranged so as to protrude from two
`opposite side regions of the resin package. A predetermined
`lead terminal among the plurality of lead terminals, con-
`nected to a portion where the light emitting element is
`die-bonded, is bent upwards, and soldered to the reflector by
`solder paste.
`
`5,660,461 A *
`
`8/1997 Ignatius et al.
`
`............. 362/241
`
`2 Claims, 8 Drawing Sheets
`
`
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`Cree Ex. 1006
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`Page 1
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`Cree Ex. 1006
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`Page 1
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 1 0f 8
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`US 7,282,740 B2
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`FIG.1
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`FIG.2
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`Cree Ex. 1006
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`Page 2
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`Cree Ex. 1006
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 2 0f 8
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`US 7,282,740 B2
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`FIG.3
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`FIG.4
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`3a
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`2a:2b
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`2 1'0
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`3a
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`Cree Ex. 1006
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 3 0f 8
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`US 7,282,740 B2
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`FIG.5
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`Cree Ex. 1006
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`Page 4
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 4 0f 8
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`US 7,282,740 B2
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`FIG.6
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`FIG]
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`Cree Ex. 1006
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 5 0f 8
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`US 7,282,740 B2
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`5
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`5
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`5
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`p41
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`! 1
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`|
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`l
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`0/11
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`! |
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`|
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`l
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`PrH
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`FIG.8
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`FIG.9
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`FIG.1O
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 6 0f 8
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`US 7,282,740 B2
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`FIG.1 1
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`24b24b
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`24b24b
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`FIG.12
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 7 0f 8
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`US 7,282,740 B2
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`FIG.13
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`FIG.14
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 8 0f 8
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`US 7,282,740 B2
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`FIG.15
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`PRIOR ART
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`
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`Vlllllln4
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`104a
`104a
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`101
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`ma
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`US 7,282,740 B2
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`1
`SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`This nonprovisional application is based on Japanese
`Patent Application No. 2003-419585 filed with the Japan
`Patent Office on Dec. 17, 2003, the entire contents of which
`are hereby incorporated by reference.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`
`The present invention relates to semiconductor light emit-
`ting devices, and more particularly, to a semiconductor light
`emitting device including a light emitting element.
`2. Description of the Background Art
`In general semiconductor light emitting devices employed
`as the illumination device of a camera, the backlight of a
`liquid crystal display device, and the like, much current is
`conducted to achieve higher luminosity. However, a large
`current flow to the semiconductor light emitting device will
`cause increase of the temperature of the light emitting
`element per se, leading to poor light emitting efliciency to
`degrade the light emitting element in the worst case.
`Therefore, measures to release the heat generated at the
`light emitting element outside efliciently in order to lower
`the temperature of the light emitting element have been
`adopted. One such measure is to increase the area or the
`thickness of the lead frame to which the light emitting
`element is die-bonded. Another known measure is to replace
`the material around the light emitting element with a mate-
`rial of high heat conductance.
`In order to achieve high luminosity in the semiconductor
`light emitting device,
`the method of directing the light
`emitted from a light emitting element to a specified direction
`is employed. A resin lens or a reflector is attached to direct
`light towards the specified direction.
`Additionally, a semiconductor light emitting device hav-
`ing the aforementioned measures combined is proposed to
`emit light of higher luminosity towards a specified direction.
`By way of example, one such semiconductor light emitting
`device disclosed in Japanese Patent Laying-Open No. 2003-
`115615 will be described hereinafter. Referring to FIG. 15,
`a light emitting element 103 and a reflector 105 are provided
`on the surface of a substrate 101. Two leads 104a and 10419
`
`of light emitting element 103 is soldered 107 to the wiring
`of substrate 101. A predetermined resin 109 is provided at
`the region of leads 104a and 10419 and the region of reflector
`105.
`
`In this semiconductor light emitting device, leads 104a
`and 10419 are brought into direct contact with resin 109 to
`achieve heat dissipation by allowing the heat generated at
`light emitting element 103 to be conducted to reflector 105
`via resin 109.
`
`Additionally, Japanese Patent Laying-Open Nos. 2002-
`176203 and 2003-197974 disclose a semiconductor light
`emitting device that achieves heat dissipation by conducting
`the heat generated at a light emitting element to a reflector
`via resin having high heat conductivity. The semiconductor
`light emitting device disclosed in Japanese Patent Laying-
`Open No. 2002-176203 has the reflector formed integrally
`with the lead to allow direct conduction of heat generated at
`the light emitting element to the reflector without the inter-
`vention of resin and the like.
`
`The semiconductor light emitting devices set forth above
`had the following problems. If the heat generated at the light
`emitting element is to be conducted to a reflector via resin,
`the resin must be cured with the reflector fixed at a prede-
`
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`termined location with respect to the substrate and the light
`emitting element so as to achieve fixation between the
`reflector and the substrate. Therefore, a dedicated jig to
`position the reflector at predetermined site was required
`since heat conduction cannot be achieved efficiently if the
`position of the reflector is deviated. Furthermore,
`it was
`necessary to control the amount of resin during the fixation
`of the reflector so that the resin does not flow excessively to
`a region where resin is not required. In the case where the
`reflector and lead are formed integrally, the semiconductor
`light emitting device will have the reflector covered with
`mold resin since the reflector and lead are formed integrally
`from the beginning. Thus, there was the problem that heat
`cannot be released efliciently to the air from the reflector.
`
`SUMMARY OF THE INVENTION
`
`In view of the foregoing, an object of the present inven-
`tion is to provide a semiconductor light emitting device that
`can achieve heat conduction reliably towards a reflector and
`that can release heat efliciently from the reflector to the air.
`A semiconductor light emitting device according to the
`present invention includes a lead frame, a semiconductor
`light emitting element, a sealing member, and a reflector.
`The lead frame includes a plurality of lead terminals. The
`semiconductor light emitting element is die-bonded to the
`lead frame. The sealing member seals the lead frame such
`that each of the plurality of lead terminals and the semicon-
`ductor light emitting element are exposed. The reflector is
`attached to the sealing member to emit the light output by
`the semiconductor light emitting element towards one direc-
`tion. A predetermined lead terminal among the plurality of
`lead terminals, connected to the region of the lead frame to
`which the semiconductor light emitting device is die-
`bonded, is arranged towards the side where the reflector is
`located to be connected to the reflector.
`
`In accordance with such a configuration, a predetermined
`lead terminal connected to the region where the semicon-
`ductor light emitting device is die-bonded is connected to
`the reflector. Accordingly, the heat generated at the semi-
`conductor light emitting element is reliably conducted to the
`reflector via the predetermined lead terminal. As a result, the
`heat conducted to the reflector can be released efliciently by
`the reflector.
`
`In order to couple the reflector with the predetermined
`lead terminal by, for example, attachment,
`the reflector
`preferably includes an attach region to attach the predeter-
`mined lead terminal. Particularly,
`it is desirable that the
`predetermined lead terminal is fixed to the reflector by a
`conductive material.
`
`The sealing member is formed having side regions facing
`each other. When the plurality of lead terminals are respec-
`tively arranged so as to protrude from the sealing member
`along one of the side regions facing each other, the prede-
`termined lead terminal is preferably arranged at one end of
`the plurality of lead terminals respectively disposed along
`one of the side regions.
`Accordingly, the predetermined lead terminal can be bent
`towards the region of the sealing member where the reflector
`is disposed without covering the semiconductor light emit-
`ting element exposed at the sealing member. The area of
`connection between the reflector and the predetermined lead
`terminal can be ensured to allow the reflector to be supported
`and fixed more stably.
`Furthermore, in the case where there is another predeter-
`mined lead terminal connected to the portion of the lead
`frame to which the semiconductor light emitting element is
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`US 7,282,740 B2
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`3
`is
`that another predetermined lead terminal
`die-bonded,
`preferably arranged at the other end of the plurality of lead
`terminals respectively disposed along one side region.
`Accordingly,
`the predetermined lead terminal and the
`another predetermined lead terminal connected to the reflec-
`tor are disposed such that
`the distance therebetween is
`greatest. As a result, the reflector can be supported and fixed
`more stably by the predetermined lead terminal and the
`another predetermined lead terminal.
`In the above-described case where the lead frame includes
`
`another predetermined lead terminal connected to the region
`of the lead frame to which the semiconductor light emitting
`element is die-bonded, the sealing member includes side
`regions facing each other, and the predetermined lead ter-
`minals are arranged so as to protrude from the sealing
`member along respective side regions facing each other, the
`predetermined lead terminal and the another predetermined
`lead terminal are preferably disposed at a position where the
`distance between the predetermined lead terminal and the
`another predetermined lead terminal is greatest.
`Accordingly, the reflector is supported and fixed more
`stably through the predetermined lead terminal and the
`another predetermined lead terminal by Virtue of the prede-
`termined lead terminal and another predetermined lead
`terminal connected to the reflector such that the distance
`
`between these lead terminals is greatest.
`There is further provided a groove at a region of the
`sealing member where the reflector is located to receive the
`predetermined lead terminal. The depth of the groove is
`preferably set such that the surface of the predetermined lead
`terminal and the surface of the sealing member where the
`reflector is located is substantially on the same plane as the
`predetermined lead terminal received in the groove.
`By setting the top face of the predetermined lead terminal
`substantially flush with the top face of the sealing member,
`the reflector is brought into contact with the sealing member
`in addition to the predetermined lead terminal. As a result,
`the reflector can be supported and fixed further stably by the
`predetermined lead terminal and sealing member.
`Alternatively, the reflector can be formed by folding and
`bending a member that becomes the reflector. This member
`is formed integrally with the predetermined lead terminal in
`an unfolded manner, corresponding to an expansion plan.
`In this case, the step of coupling the predetermined lead
`terminal with the reflector is no longer required. Since the
`reflector is formed integrally with the leading end of the
`predetermined lead terminal, the reflector can be supported
`reliably by the predetermined lead terminal.
`Such a member to constitute a reflector specifically
`includes a reflector body and another reflector body, a
`projection provided at one of the reflector body and the
`another reflector body, and a notch provided at the other of
`the reflector body and the another reflector body. In the
`reflector, the projection preferably engages with the notch.
`In the case where the reflector is provided as a separate
`piece without being formed integrally with the leading end
`of the predetermined lead terminal, the degree of freedom of
`the configuration of the reflector is increased. For example,
`in the case where there is another sealing member that seals
`another lead frame to which another semiconductor light
`emitting element is die-bonded, the reflector can be disposed
`so as to bridge between the sealing member and the another
`sealing member.
`Furthermore, the reflector preferably includes at least one
`of a flat portion and a curved portion as the region to reflect
`light from the standpoint of improving the degree of free-
`dom of light reflection.
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`Specifically, a reflector can be used having a reflection
`plane whose configuration in cross section parallel to the
`optical axis is formed of a straight line, or a reflection plane
`whose configuration in cross section parallel to the optical
`axis is formed of a curve constituting a parabola, a portion
`of an ellipse, or an arc. Furthermore, a reflector can be used
`whose configuration in plane in a direction substantially
`orthogonal to the optical axis is a rectangle, a shape formed
`of two arcs and a straight line connecting these arcs, a shape
`corresponding to a portion of the curve of an ellipse or a
`parabola being partially coupled, or the like.
`In order to release heat efliciently from the reflector to the
`air, preferably the entire reflector is exposed to the air.
`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.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view of a semiconductor light
`emitting device according to a first embodiment of the
`present invention.
`FIG. 2 is a plan view of a modification of the semicon-
`ductor light emitting device of the first embodiment.
`FIG. 3 is a plan view of a semiconductor light emitting
`device according to a second embodiment of the present
`invention.
`
`FIG. 4 is a side view of the semiconductor light emitting
`device of FIG. 3.
`
`FIG. 5 is an exploded plan view of a semiconductor light
`emitting device according to a third embodiment of the
`present invention.
`FIG. 6 is a perspective view of the semiconductor light
`emitting device of FIG. 5 of the third embodiment.
`FIG. 7 is an exploded plan view of a semiconductor light
`emitting device according to a fourth embodiment of the
`present invention.
`FIGS. 8, 9 and 10 are sectional views of the semiconduc-
`tor light emitting device of respective embodiments, repre-
`senting examples of the configuration of the cross section of
`the reflector.
`FIGS. 11, 12, 13 and 14 are sectional views of the
`semiconductor light emitting device of respective embodi-
`ments, representing examples of the configuration of the
`plane of the reflector.
`FIG. 15 is a sectional view of a conventional semicon-
`
`ductor light emitting device.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`First Embodiment
`
`Referring to FIGS. 1 and 2, a semiconductor light emit-
`ting device according to a first embodiment of the present
`invention has an opening 10 formed at a top face of a resin
`package 3. A light emitting element 2 is die-bonded to a
`region of a lead frame 1 exposed at the bottom of opening
`10. At a top face of resin package 3, a reflector 5 is attached
`to direct the light emitted by the light emitting element 2
`towards a predetermined direction. Reflector 5 is attached
`such that its entirety is exposed to the air.
`Respective lead terminals 4a and 4b of lead frame 1 are
`disposed so as to project from each of the two opposite side
`regions of resin package 3. Among the plurality of lead
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`5
`terminals 4a and 4b, a predetermined lead terminal 4a
`connected to the region where light emitting element 2 is
`die-bonded is bent upward. The leading end of the bent lead
`terminal 4a is soldered by, for example, solder paste 6 to a
`fringe portion identified as an attach region 5a of reflector 5.
`The remaining lead terminals 4b are respectively bent down-
`wards for connection to the wiring (not shown) formed at the
`substrate. Lead terminal 4b is electrically connected to light
`emitting element 2 Via leads 2a and 2b.
`The two lead terminals 4a connected to reflector 5 are
`
`disposed diagonally opposite to each other at resin package
`3 such that the distance between these two lead terminals is
`
`greatest.
`light emitting
`In the above-described semiconductor
`device, lead terminal 4a connected to the region where light
`emitting element 2 is die-bonded is connected to reflector 5.
`Accordingly, the heat generated at light emitting element 2
`is reliably conducted to reflector 5 Via lead terminal 4a. The
`heat conducted to reflector 5 is released efliciently to the air
`by reflector 5 that is entirely exposed to the air.
`light
`By the eflicient dissipation of heat generated at
`emitting element 2 through reflector 5, a relatively large
`current can be conducted to light emitting element 2 to allow
`increase of the luminosity. Furthermore,
`temperature
`increase of the light emitting element
`is suppressed to
`improve the reliability of light emitting element 2. Addi-
`tionally, degradation of light emitting element 2 can be
`suppressed.
`The two lead terminals 4a connected to reflector 5 are
`
`disposed on the diagonal of resin package 3. Accordingly,
`reflector 5 is supported by lead terminals 4a disposed such
`that
`the distance therebetween is greatest. As a result,
`reflector 5 can be supported and fixed more stably by the
`lead terminals 411.
`
`The present embodiment was described based on an
`example where lead terminal 4a and reflector 5 are con-
`nected by solder paste 6. Alternatively, appropriate conduc-
`tive paste such as silver (Ag) paste can be used. The
`conductive paste has high heat conduction by the inclusion
`of metal particles.
`The foregoing semiconductor light emitting device is
`described based on an example where respective lead ter-
`minals 4a and 4b are disposed projecting from two opposite
`side regions of resin package 3. Alternatively, the semicon-
`ductor light emitting device may have the lead terminals
`respectively disposed so as to protrude from only one of the
`side regions of the resin package.
`In this case,
`the two lead terminals 4a connected to
`reflector 5 are preferably disposed at one end and the other
`end such that the distance between these two lead terminals
`
`is greatest. Accordingly, reflector 5 can be supported and
`fixed more stably by the two lead terminals 411.
`The number of lead terminals connected to the reflector is
`
`not limited to two; and three or more, or only one can be
`provided. Particularly in the case where only one lead
`terminal
`is connected to the reflector,
`the endmost
`lead
`terminal is preferably connected to the reflector. Accord-
`ingly, the lead terminal can be bent up towards the top face
`of the resin package while opening 10 (refer to FIG. 1)
`provided at the top face of resin package 3 is not covered.
`The reflector can be supported and fixed more stably while
`ensuring a connecting area between the reflector and lead
`terminal.
`
`6
`Second Embodiment
`
`A semiconductor light emitting device according to a
`second embodiment of the present invention is directed to
`fixing the reflector more stably to the resin package.
`Referring to FIGS. 3 and 4, a groove 3a is formed in
`advance at the top face of resin package 3 such that the top
`plane of lead terminal 4a is substantially flush with the top
`face of resin package 3 with lead terminal 4a connected to
`reflector 5 (refer to FIG. 1)
`in a bending status. The
`remaining configuration of the semiconductor light emitting
`device of the second embodiment is similar to the semicon-
`
`ductor light emitting device shown in FIG. 1. Therefore, the
`same elements have the same reference characters allotted,
`and description thereof will not be repeated.
`In the semiconductor light emitting device of the second
`embodiment, lead terminal 4a connected to reflector 5 is
`received in groove 3a provided at the top face of resin
`package 3 by being bent towards the top face of resin
`package 3. Accordingly, the top face of lead terminal 4a is
`substantially flush with the top face of resin package 3, so
`that reflector 5 is brought into contact with the top face of
`resin package 3 in addition to lead terminal 4a. As a result,
`reflector 5 is supported and fixed further stably by both the
`top faces of lead terminal 4a and resin package 3, as
`compared to the foregoing semiconductor light emitting
`device.
`
`In the semiconductor light emitting device of the second
`embodiment,
`lead terminal 4a in a bent status will not
`protrude above the top face of resin package 3. Therefore,
`the semiconductor light emitting device prior to attachment
`of a reflector can be handled easier.
`
`Third Embodiment
`
`A semiconductor light emitting device according to a third
`embodiment of the present invention has a reflector formed
`integrally with the lead frame. Referring to FIG. 5, a portion
`to become reflector 5 is formed integrally with the leading
`end of lead terminal 411. This portion to become the reflector
`is formed in a state (shape) in which the reflector is spread
`out in an unfolded manner corresponding to an expansion
`plan,
`including four reflector bodies 55 in the present
`embodiment.
`
`A projection 55a is provided at one of adjacent reflector
`bodies 55. A notch 55b to be engaged with projection 55a is
`provided at the other of the adjacent reflector bodies 55.
`By bending each reflector body 55 and holding projection
`55a of reflector body 55 under engagement with notch 55b
`of an adjacent reflector body 55, reflector 5 is assembled. A
`semiconductor light emitting device having reflector 5 at the
`top face of resin package 3 is obtained, as shown in FIG. 6.
`The remaining elements are similar to those of the semi-
`conductor light emitting device of FIG. 1. Therefore, cor-
`responding elements have the same reference characters
`allotted, and description thereof will not be repeated.
`In the semiconductor light emitting device of the third
`embodiment, the portion to become reflector 5 is formed
`integrally with the leading end of lead terminal 4a, taking a
`configuration in which reflector 5 is spread out
`in an
`unfolded manner corresponding to an expansion plan.
`Therefore,
`the step of connecting lead terminal 4a with
`reflector 5 is not longer necessary. Assembly of the portions
`constituting the reflector leads to a state where reflector plate
`5 is attached integrally to the leading end of lead terminal 411.
`As a result, reflector 5 is reliably supported and fixed to lead
`terminal 411.
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`Cree Ex. 1006
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`Cree Ex. 1006
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`US 7,282,740 B2
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`7
`Since reflector plate 5 and lead terminal 4a are connected
`integrally, higher heat conduction is achieved, as compared
`to the case where the reflector plate is attached to the lead
`terminal. Thus, heat dissipation can be effected more efli-
`ciently.
`The semiconductor light emitting device set forth above
`was described based on an example having a flat reflection
`plane for the reflector. Alternatively, a reflector having a
`curved reflection plane can be employed depending upon the
`shape in which the reflector is spread out in an unfolded
`manner and the assembly by, for example a bending process.
`
`Fourth Embodiment
`
`A semiconductor light emitting device including a plu-
`rality of resin packages in which a light emitting element is
`incorporated will be described here as a semiconductor light
`emitting device of the fourth embodiment. Referring to FIG.
`7, reflector 5 is disposed so as to bridge across two resin
`packages 3. A lead terminal 4a connected to the portion
`where a light emitting element (not shown) is die-bonded is
`connected to reflector 5, likewise the semiconductor light
`emitting device described above.
`By providing reflector 5 separately from the lead frame in
`the semiconductor light emitting device set forth above, the
`degree of freedom for attaching reflector 5 becomes higher.
`One reflector 5 can be attached with respect to two resin
`packages 3. Since lead terminal 4a coupled to the region
`where light emitting element 2 is die-bonded is connected,
`the heat generated at light emitting element 2 can be released
`efliciently by reflector 5. As a result, the heat conducted to
`reflector 5 can be released efliciently through reflector 5.
`The above embodiment was described based on an
`
`example in which one reflector 5 is provided for two resin
`packages 3. The number of resin packages 3 is not limited
`to two. A semiconductor light-emitting device having one
`reflector arranged for three or more resin packages can be
`provided.
`The semiconductor light emitting devices of respective
`embodiments set forth above were described based on an
`
`example in which reflector 5 has a reflection plane whose
`configuration in cross section along an optical axis 11 is
`formed of a straight line, as shown in FIG. 8. Additionally,
`a reflector 5 having a reflection plane whose configuration in
`cross section is formed of a curve constituting a parabola or
`a portion of an ellipse can be disposed at the resin package,
`as shown in FIG. 9. Alternatively, a reflector 5 having a
`reflection plane whose configuration in cross section is
`formed of a curve constituting an arc can be disposed at the
`resin package, as shown in FIG. 10.
`The semiconductor light emitting devices of respective
`embodiments set forth above were described based on an
`
`example in which reflector 5 whose configuration in plane in
`a direction substantially orthogonal to the optical axis is a
`rectangle. Additionally, in the case where two light emitting
`elements 2 are arranged, a reflector 5 whose configuration in
`plane in a direction substantially orthogonal to the optical
`axis is an ellipse with a major axis set along the direction
`where the two light emitting elements are arranged can be
`disposed at resin package 3, as shown in FIG. 11.
`Furthermore, a reflector 5 whose configuration in plane
`takes a shape formed of two arcs and a straight line con-
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`necting these arcs can be disposed at resin package 3, as
`shown in FIG. 12. Alternatively, a reflector 5 whose con-
`figuration in plane takes a shape corresponding to a portion
`of the curve of an ellipse, a parabola or the like being
`coupled, can be disposed at resin package 3, as shown in
`FIG. 13.
`
`In a reflector whose configuration in plane in a direction
`substantially orthogonal to the optical axis is a rectangle, the
`four sheet-like reflection planes are preferably disposed in
`an inclined manner such that each spreads upwards, as
`shown in FIG. 14. Accordingly, light emitted from the light
`emitting element can be output efliciently in one direction.
`By providing the reflector as a separate piece with respect
`to the lead frame, the shape of the reflector can be selected
`in accordance with the semiconductor light emitting device.
`The degree of freedom of the emission property of light
`output from the light emitting element becomes higher.
`Furthermore, with regards to a common semiconductor light
`emitting device prior to attachment of a reflector, various
`reflectors can be applied.
`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.
`
`What is claimed is:
`
`1. A semiconductor light emitting device comprising:
`a lead frame including a plurality of lead terminals,
`a semiconductor light emitting element die-bonded to said
`lead frame,
`a sealing member sealing said lead frame such that each
`of said plurality of lead terminals and said semicon-
`ductor light emitting element are exposed, and
`a reflector attached to said sealing member to direct light
`emitted by said semiconductor light emitting element
`towards one direction,
`wherein a predetermined lead terminal among said plu-
`rality of lead terminals is arranged towards a side where
`said reflector is located and connected to said reflector,
`said predetermined lead terminal being connected to a
`portion of said lead frame to which said semiconductor
`light emitting element is die-bonded,
`wherein said reflector is formed by bending a member to
`become said reflector, formed integrally with said pre-
`determined lead terminal in a state in which the reflec-
`
`tor is spread out in an unfolded manner corresponding
`to an expansion plan.
`2. The semiconductor light emitting device according to
`claim 1, wherein said member to become a reflector com-
`prises
`a reflector body and another reflector body,
`a projection provided at one of said reflector body and
`said another reflector body, and
`a notch provided at the other of said reflector body and
`said another reflector body,
`said projection being engaged with said notch at said
`reflector.
`
`Cree Ex. 1006
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`Page 13
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`Cree Ex. 1006
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`Page 13
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