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`US 20050151149Al
`
`(19) United States
`(12) Patent Application Publication
`Chia et al.
`
`(10) Pub. No.: US 2005/0151149 Al
`Jul. 14, 2005
`( 43) Pub. Date:
`
`(54) LIGHT EMISSION DEVICE
`
`(22) Filed:
`
`Jan. 8,2004
`
`(76)
`
`Inventors: Chee Wai Chia, Penang (MY); Hui
`Peng Koay, Penang (MY); Lye Yee
`Wong, Penang (MY)
`
`Correspondence Address:
`AGILENT TECHNOLOGIES, INC.
`Legal Department, DL429
`Intellectual Property Administration
`P.O. Box 7599
`Loveland, CO 80537-0599 (US)
`
`(21)
`
`Appl. No.:
`
`10/755,047
`
`Publication Classification
`
`Int. Cl.7 ..................................................... HOlL 33/00
`(51)
`(52) U.S. Cl. ................................................................ 257/99
`
`ABSTRACT
`(57)
`A light emission device. A lead frame comprises a first lead
`frame segment and a second lead frame segment. A light
`source is coupled to the first lead frame segment. A wire
`bond is coupled to the light source and coupled to the second
`lead frame segment. A translucent epoxy cast encases the
`light source, the wire bond and a portion of the lead frame.
`
`VIZIO Ex. 1020 Page 00001
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`

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`Patent Application Publication Jul. 14, 2005 Sheet 1 of 6
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`US 2005/0151149 Al
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`VIZIO Ex. 1020 Page 00002
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`Patent Application Publication Jul. 14, 2005 Sheet 2 of 6
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`VIZIO Ex. 1020 Page 00003
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`Patent Application Publication Jul. 14, 2005 Sheet 3 of 6
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`US 2005/0151149 Al
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`Figure 5A
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`VIZIO Ex. 1020 Page 00004
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`

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`Patent Application Publication Jul. 14, 2005 Sheet 4 of 6
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`VIZIO Ex. 1020 Page 00005
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`Patent Application Publication Jul. 14, 2005 Sheet 5 of 6
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`US 2005/0151149 Al
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`VIZIO Ex. 1020 Page 00006
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`

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`Patent Application Publication Jul. 14, 2005 Sheet 6 of 6
`
`US 2005/0151149 Al
`
`910
`Couple a light source to a first lead frame segment of a
`
`Couple a wire bond to the light source and a second lead
`frame segment of the lead frame
`
`Coupling a second wire bond to the first lead frame
`segment and the light source
`
`lead frame • 920
`• 925
`• 930
`
`Encase the light source, the wire bond, and a portion of the
`lead frame in a translucent epoxy cast
`
`940
`Form a shaped portion of the translucent epoxy cast
`incident to the light source
`
`Dye the translucent epoxy cast with a color tinting
`
`!
`
`• 950
`• 960
`
`Diffuse at least a portion of the translucent epoxy cast
`
`Figure 9
`
`VIZIO Ex. 1020 Page 00007
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`US 2005/0151149 Al
`
`Jul. 14, 2005
`
`1
`
`LIGHT EMISSION DEVICE
`
`FIELD OF INVENTION
`[0001] Various embodiments of the present invention
`relate to the field of light emission devices.
`
`BACKGROUND OF THE INVENTION
`[0002] Light emitting diodes (LEDs) are display devices
`that use a semiconductor diode that emits light when charged
`with electricity. LEDs provide light in a wide array of
`electronic devices. For example, LEDs are used as on/off
`indicators in electronic devices, are used to provide LCD or
`keypad backlighting in handheld devices, such as personal
`digital assistants (PDAs) and cellular telephones, and are
`used for digital display readouts, such as electronic signs.
`Typically, LEDs are manufactured into an electronic chip
`(e.g., LED chips) that provide for easy integration into
`electronic devices.
`[0003] Conventional LED chips employ surface mount
`technology (SMT) using a printed circuit board (PCB) as a
`base, with the LED die encapsulated into an epoxy resin.
`The encapsulating process typically used is transfer mold(cid:173)
`ing, which utilizes high temperature and pressure to melt the
`mold compound and force it into the mold cavity. Due to the
`use of SMT and transfer molding epoxy encapsulation, there
`are a number of problems inherent to the used of conven(cid:173)
`tional LED chips.
`[0004] Typical LED chips are subject to thermal break(cid:173)
`down as a result of the poor thermal dissipation properties of
`a typical PCB. Due to the poor heat dissipation of a typical
`PCB, an LED used in a high power or high brightness
`application, may fail. Therefore, typical LED chips are
`restricted to low power or brightness, or have short life
`spans.
`[0005] Furthermore, an encapsulating process using trans(cid:173)
`fer molding creates an epoxy molding over an LED on top
`of a PCB. An LED chip subjected to the elements is prone
`to delamination caused by moisture absorption. Delamina(cid:173)
`tion causes the epoxy molding to separate from the PCB,
`exposing the LED die to moisture, and eventually leading to
`failure. Due to the wide number of electronic devices using
`LEDs that are exposed to the elements, delamination is a
`wide problem. Moreover, transfer molding requires expen(cid:173)
`sive tools, machines and materials, requiring a substantial
`investment that is not typically viable for small- and
`medium-scale production.
`
`SUMMARY OF THE INVENTION
`[0006] Various embodiments of the present invention, a
`light emission device and a method for generating a light
`emission device, are described herein. In one embodiment,
`the light emission device comprises a lead frame comprising
`a first lead frame segment and a second lead frame segment.
`A light source is coupled to the first lead frame segment. A
`wire bond is coupled to the light source and coupled to the
`second lead frame segment. A translucent epoxy cast
`encases the light source, the wire bond and a portion of the
`lead frame.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`[0007] The accompanying drawings, which are incorpo(cid:173)
`rated in and form a part of this specification, illustrate
`
`invention and, together with the
`embodiments of the
`description, serve to explain the principles of the invention:
`
`[0008] FIG. 1 illustrates a side view of a light emission
`device in accordance with an embodiment of the present
`invention.
`
`[0009] FIG. 2 illustrates a side view of a light emission
`device in accordance with another embodiment of the
`present invention.
`
`[0010] FIG. 3 illustrates an isometric view of a lead frame
`of a light emission device in accordance with an embodi(cid:173)
`ment of the present invention.
`
`[0011] FIG. 4 illustrates a cut-away cross-sectional view
`of a light emission device in accordance with an embodi(cid:173)
`ment of the present invention.
`
`[0012] FIG. SA illustrates a cut-away side view of a light
`emission device including a round shape epoxy dome in
`accordance with an embodiment of the present invention.
`
`[0013] FIG. 5B illustrates a top view of a light emission
`device including a round shape epoxy dome in accordance
`with an embodiment of the present invention.
`
`[0014] FIG. 6A illustrates a cut-away side view of a light
`emission device including an oval shape epoxy dome in
`accordance with an embodiment of the present invention.
`
`[0015] FIG. 6B illustrates a top view of a light emission
`device including an oval shape epoxy dome in accordance
`with an embodiment of the present invention.
`
`[0016] FIG. 7 illustrates a side view of a light emission
`device including a hemispherical reflector cup in accordance
`with an embodiment of the present invention.
`
`[0017] FIG. 8 illustrates side view of a light emission
`device including a flat top epoxy surface and including a first
`wire bond and a second wire bond in accordance with an
`embodiment of the present invention.
`
`[0018] FIG. 9 is a flow chart illustrating a process for
`generating a light emission device in accordance with an
`embodiment of the present invention.
`
`BEST MODE(S) FOR CARRYING OUT THE
`INVENTION
`
`[0019] Reference will now be made in detail to various
`embodiments of the invention, examples of which are illus(cid:173)
`trated in the accompanying drawings. While the invention
`will be described in conjunction with various embodiments,
`it will be understood that they are not intended to limit the
`invention to these embodiments. On the contrary, the inven(cid:173)
`tion is intended to cover alternatives, modifications and
`equivalents, which may be included within the spirit and the
`scope of the invention as defined by the appended claims.
`Furthermore, in the following detailed description of the
`present invention, numerous specific details are set forth in
`order to provide a thorough understanding of the present
`invention. However, it will be apparent to one skilled in the
`art that the present invention may be practiced without these
`specific details. In other instances, well-known methods,
`procedures, components, structures and devices have not
`been described in detail so as to avoid unnecessarily obscur(cid:173)
`ing aspects of the present invention.
`
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`US 2005/0151149 Al
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`Jul. 14, 2005
`
`2
`
`[0020] FIG. 1 illustrates a side view of an exemplary light
`emission device 100 in accordance with an embodiment of
`the present invention. Light emission device 100 comprises
`light source 105, wire bond 110, and a lead frame compris(cid:173)
`ing first lead frame segment 115 and second lead frame
`segment 120. Light source 105, wire bond 110 and at least
`a portion of the lead frame are encased in epoxy cast 125. It
`should be appreciated that a lead frame refers to a type of
`chip package that uses conductive leads that extend outside
`of a housing. In the present embodiment, a portion of first
`lead frame segment 115 and a portion of second lead frame
`segment 120 are not encased within epoxy cast 125, allow(cid:173)
`ing for the transmission of power signals to light source 105.
`
`[0021]
`In one embodiment, the lead frame is comprised of
`copper, however, it should be appreciated that any other
`conductive material, such as another metal, may be imple(cid:173)
`mented. In one embodiment, the lead frame is covered in a
`plating to improve various properties of the lead frame. For
`example, plating may be used to improve the bonding
`strength between light source 105 and first lead frame
`segment 115 and between wire bond 110 and second lead
`frame segment 120, may enhance the adhesiveness of epoxy
`cast 125 to the lead frame, may prevent oxidization of a
`metal lead frame, may enhance to solderability of pads of
`first lead frame segment 115 and second lead frame segment
`120, and can improve the surface reflectivity to enhance flux
`extraction. In one embodiment, the plating is nickel/palla(cid:173)
`dium/gold (NiPdAu). In another embodiment, the plating is
`silver (Ag). It should be appreciated that any other plating
`material may be implemented depending on the design
`requirements of light emission device 100.
`
`[0022] A lead frame provides improved thermal dissipa(cid:173)
`tion over the use of a PCB substrate, due to the lower
`thermal resistance. Light emission device 100 can be sub(cid:173)
`jected to higher operating current due to the better heat
`dissipation properties of the lead frame. Therefore, the
`luminous intensity of light emission device 100 can be
`increased. Furthermore, light emission device 100 may have
`a lower profile due to a lead frame being thinner than a PCB
`substrate.
`
`[0023] Light source 105 is coupled to first lead frame
`segment 115. In one embodiment, a power signal is received
`at light source 105 from first lead frame segment 115. In one
`embodiment, light source 105 is a light emitting diode
`(LED) die. While embodiments of the invention are
`described using an LED, it should be appreciated that other
`types of light sources may be implemented, such as an
`infrared emitting diode (IRED) or a laser diode. Wire bond
`110 is coupled to light source 105 and second lead frame
`segment 120. Light source 105 receives positive and nega(cid:173)
`tive power signals via first lead frame segment 115 and wire
`bond 110, and emits light in response to such signals. In one
`embodiment, wire bond 110 is a gold wire. However, it
`should be appreciated than any conductive material may be
`implemented at wire bond 110. In one embodiment, first lead
`frame segment 115 operates as a cathode for transmitting a
`negative power signal, and second lead frame 120 operates
`as an anode for transmitting a positive power signal, as
`indicated at anode mark 130.
`
`[0024] Epoxy cast 125 is formed over light source 105,
`wire bond 110, a portion of first lead frame segment 115 and
`an portion of second lead frame segment 120 using an epoxy
`
`casting process. The use of a conductive lead frame substrate
`provides for the use of a conventional casting process in
`forming epoxy cast 125. In one embodiment, epoxy cast 125
`is comprised of substantially half epoxy resin and substan(cid:173)
`tially half epoxy hardener. However, it should be appreciated
`that any combination of epoxy resin and epoxy hardener
`may be used. Epoxy cast 125 is translucent, allowing for the
`passage of light. In one embodiment, epoxy cast 125 com(cid:173)
`prises a color tinting for filtering the wavelength of light
`passing through epoxy cast 125. In one embodiment, epoxy
`cast 125 is operable to diffuse light passing through epoxy
`cast 125. Using a casting process to generate epoxy cast 125
`provides a substantial cost savings over transfer molding
`process due to the high volume per run with high density
`lead frame design as well as lower initial tooling costs.
`Furthermore, epoxy cast 125 provides improved moisture
`absorption resistivity compared to molding compound
`which is more sensitive to moisture.
`
`[0025] FIG. 2 illustrates a side view of light emission
`device 200 in accordance with another embodiment of the
`present invention. Light emission device 200 comprises
`light source 205, wire bond 210, and a lead frame compris(cid:173)
`ing first lead frame segment 215 and second lead frame
`segment 220. Light source 205, wire bond 210 and at least
`a portion of the lead frame are encased in epoxy cast 225.
`Light emission device 200 is similar to light emission device
`100 of FIG. 1, while providing additional features.
`
`[0026] Light emission device 200 comprises recess 235
`for receiving light source 205 such that light source 205
`resides at least partially within recess 235. Placing light
`source 205 within recess 235 assists in providing a low
`profile for light emission device 200, thereby allowing wider
`applicability. Light source 205 is coupled to first lead frame
`segment 215 and wire bond 210, and wire bond 210 is also
`coupled to second lead frame segment 220. Light source 205
`receives positive and negative power signals via first lead
`frame segment 215 and wire bond 210, and emits light in
`response to such signals. In one embodiment, first lead
`frame segment 215 operates as a cathode for transmitting a
`negative power signal, and second lead frame 220 operates
`as an anode for transmitting a positive power signal, as
`indicated at anode mark 230.
`
`[0027] With reference to FIG. 3, an isometric view of the
`lead frame of light emission device 200 is illustrated, in
`accordance with an embodiment of the present invention.
`Recess 235 is configured for receiving a light source (e.g.,
`light source 205 of FIG. 2).
`
`[0028] With reference to FIG. 2, the lead frame of light
`emission device 200 also comprises at least one anchoring
`recess for allowing epoxy cast 225 to be anchored to first
`lead frame segment 215 and second lead frame segment 220.
`In one embodiment, first lead frame segment 215 comprises
`anchoring recess 250, such that during epoxy casting,
`anchoring recess 250 is filled such that epoxy cast 225 is
`anchored to first lead frame segment 215.
`
`[0029] FIG. 4 illustrates a cut-away cross-sectional view
`of light emission device 200 of FIG. 2, in accordance with
`an embodiment of the present invention. The cut-away
`cross-sectional view of FIG. 4 shows the cross-sectional
`area of light emission device 200 at dotted line 280 of FIGS.
`2 and 3. As shown in FIG. 4, the illustrated portion of first
`
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`
`Jul. 14, 2005
`
`3
`
`lead frame segment 215 is completely surrounded by epoxy
`cast 225. In particular, anchoring recess 250 is completely
`filled with epoxy cast 225.
`[0030] With reference to FIG. 2, first lead frame segment
`215 also comprises anchoring recesses 245 and 255, and
`second lead frame segment 220 comprises anchoring
`recesses 240 and 260. Anchoring recesses 240, 245, 255 and
`260 provide additional anchoring functionality to the lead
`frame, thereby providing increased anchorage between the
`lead frame and epoxy cast 225. With reference to FIG. 3,
`first lead frame segment 215 also comprises anchoring
`extensions 265 and 270, providing additional anchoring
`functionality by locking epoxy casting 225 to first lead
`frame segment 215. It should be appreciated that first lead
`frame segment 215 and second lead frame segment 220 may
`comprise any number of anchoring recesses and anchoring
`extensions, and that those illustrated in FIGS. 2, 3 and 4 are
`exemplary. Improving the anchorage between the lead frame
`and epoxy cast 225 prevents delamination due to operation
`of light emission device 200 under a wide range of envi(cid:173)
`ronmental conditions.
`[0031]
`In various embodiments of the present invention, a
`portion of the epoxy cast may be formed into a shape, such
`as a dome, for directing light. FIG. SA illustrates a cut-away
`side view of a light emission device 500 including a round
`shape epoxy dome in accordance with an embodiment of the
`present invention. Light emission device 500 comprises
`light source 505, wire bond 510, and a lead frame compris(cid:173)
`ing first lead frame segment 515 and second lead frame
`segment 520. Light source 505, wire bond 510 and at least
`a portion of the lead frame are encased in epoxy cast 525.
`Epoxy cast 525 comprises epoxy shaped portion 530. In the
`illustrated embodiment, shaped portion 530 is a round shape
`dome. It should be appreciated that epoxy shaped portion
`530 may be any shape (e.g., rectangular, triangular, cylin(cid:173)
`drical), and is not limited to the illustrated embodiment.
`[0032] FIG. 5B illustrates a top view of light emission
`device 500 including a round shape epoxy dome in accor(cid:173)
`dance with an embodiment of the present invention. As
`shown in FIG. 5B, epoxy shaped portion 530 is seen to
`provide for symmetric viewing angles of emitted light in all
`directions.
`[0033] FIG. 6A illustrates a cut-away side view of a light
`emission device 600 including an oval shape epoxy dome in
`accordance with an embodiment of the present invention.
`Light emission device 600 comprises light source 605, wire
`bond 610, and a lead frame comprising first lead frame
`segment 615 and second lead frame segment 620. Light
`source 605, wire bond 610 and at least a portion of the lead
`frame are encased in epoxy cast 625. Epoxy cast 625
`comprises epoxy shaped portion 630. In the illustrated
`embodiment, shaped portion 630 is an oval shape dome. As
`described at FIG. SA, it should be appreciated that epoxy
`shaped portion 630 may be any shape, and is not limited to
`the illustrated embodiment.
`[0034] FIG. 6B illustrates a top view of light emission
`device 600 including an oval shape epoxy dome in accor(cid:173)
`dance with an embodiment of the present invention. As
`shown in FIG. 6B, epoxy shaped portion 630 is seen to
`provide for asymmetric viewing angles of emitted light in all
`directions. Using an oval shape dome, the viewing angle on
`the horizontal axis is greater than the viewing angle on the
`vertical axis.
`
`[0035] FIG. 7 illustrates a side view of light emission
`device 700 including a reflector cup 735 in accordance with
`an embodiment of the present invention. Light emission
`device 700 comprises light source 705, wire bond 710, and
`a lead frame comprising first lead frame segment 715 and
`second lead frame segment 720. Light source 705, wire bond
`710 and at least a portion of the lead frame are encased in
`epoxy cast 725. Light emission device 700 is similar to light
`emission device 100 of FIG. 1, while providing additional
`features.
`[0036] Light emission device 700 comprises reflector cup
`735 for receiving light source 705 and for reflecting light
`emitted from light source 705. In one embodiment, light
`source 705 resides at least partially within reflector cup 735.
`Placing light source 705 within reflector cup 735 allows for
`enhancing and directing the light emitted by light source
`705. Furthermore, placing light source 705 within reflector
`cup 735 assists in providing a low profile for light emission
`device 700, thereby allowing wider applicability.
`[0037] Epoxy cast 725 comprises epoxy shaped portion
`730. In the illustrated embodiment, shaped portion 730 is a
`round shape dome. It should be appreciated that epoxy
`shaped portion 730 may be any shape and is not limited to
`the illustrated embodiment. The use of reflector cup 735 in
`conjunction with epoxy shaped portion 730 allows for
`directing the light emitted in a desired radiation pattern and
`viewing angle.
`[0038] As described above, embodiments of the present
`invention are configured to implement different types of
`light sources. For example, embodiments of the present
`invention may implement a double wire bonded light source
`(e.g., a double wire bonded LED). A double wire bonded
`light source is operable to receive positive and negative
`power signals through two wire bonds, respectively, rather
`than through one wire bond and through coupling the light
`source to a lead frame.
`
`[0039] FIG. 8 illustrates a side view of light emission
`device 800 including first wire bond 810 and second wire
`bond 830 in accordance with an embodiment of the present
`invention. Light emission device 800 comprises light source
`805, first wire bond 810, second wire bond 830 and a lead
`frame comprising first lead frame segment 815 and second
`lead frame segment 820. Light source 805, wire bond 810
`and at least a portion of the lead frame are encased in epoxy
`cast 825. In one embodiment, epoxy cast 825 has a flat top
`surface. It should be appreciated that a lead frame refers to
`a type of chip package that uses conductive leads that extend
`outside of a housing. First wire bond is coupled to light
`source 805 and second lead frame segment 820 and second
`wire bond 830 is coupled to light source 805 and first lead
`frame segment 815.
`
`[0040] FIG. 9 is a flow chart illustrating a process 900 for
`generating a light emission device in accordance with an
`embodiment of the present invention. For purposes of clar(cid:173)
`ity, the following discussion will refer to FIG. 2 to more
`clearly describe the present invention. However, it should be
`appreciated that other embodiments of the present invention
`may be generated according to process 900. Although spe(cid:173)
`cific steps are disclosed in process 900, such steps are
`exemplary. That is, the embodiments of the present inven(cid:173)
`tion are well suited to performing various other steps or
`variations of the steps recited in FIG. 9.
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`Jul. 14, 2005
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`4
`
`[0041] At step 910 of process 900, light source 205 is
`coupled to first lead frame segment 215 of a lead frame,
`wherein the lead frame also includes second lead frame
`segment 220. In one embodiment, light source 205 is an
`LED die. In one embodiment, first lead frame segment 215
`comprises a first recess 235 such that light source 205
`resides at least partially within first recess 235. In one
`embodiment, first recess 235 is a reflector cup ( e.g., reflector
`cup 735 of FIG. 7).
`
`[0042] At step 920, a wire bond is coupled to light source
`205 and second lead frame segment 220. In one embodi(cid:173)
`ment, as shown at step 925, a second wire bond (e.g., second
`wire bond 830 of FIG. 8) is coupled to first lead frame 215
`and light source 205. It should be appreciated that step 925
`is used when light source 205 is a double wire bonded light
`source. Accordingly, step 925 is optional.
`
`[0043] At step 930, light source 205, wire bond 210, and
`a portion of lead frame are encased in translucent epoxy cast
`225. In one embodiment, as shown at step 940, a shaped
`portion (e.g., shaped portion 530 of FIG. 5) of translucent
`epoxy cast 225 is formed. In one embodiment, the shaped
`portion is formed incident light source 205. In one embodi(cid:173)
`ment, as shown at step 950, translucent epoxy cast 225 is
`dyed with a color tinting. In one embodiment, translucent
`epoxy cast 225 is configured to act as a diffuser.
`
`[0044] Embodiments of the invention provide a light
`emission device that provides higher operating conditions
`with better heat dissipation. Furthermore, the light emission
`device has improved reliability and package robustness due
`to the use of a lead frame and an epoxy casting process, as
`well as providing better anchorage between the lead frame
`and the epoxy cast. Moreover, the lead frame can be etched
`or stamped into a desirable shape, and can provide a thinner
`package profile. The described embodiments also provide a
`light emission device that provides higher light output due to
`the improved heat dissipation, as well as a higher reflective
`surface, a reflector cup, and a shaped epoxy dome.
`
`[0045] Various embodiments of the present invention, a
`light emission device, are thus described. While the present
`invention has been described in particular embodiments, it
`should be appreciated that the present invention should not
`be construed as limited by such embodiments, but rather
`construed according to the below claims.
`
`What is claimed is:
`1. A light emission device comprising:
`
`a lead frame comprising a first lead frame segment and a
`second lead frame segment;
`
`a light source coupled to said first lead frame segment;
`
`a wire bond coupled to said light source and coupled to
`said second lead frame segment; and
`
`an epoxy cast encasing said light source, said wire bond,
`and a portion of said lead frame.
`2. The light emission device as recited in claim 1 wherein
`said first lead frame segment comprises a first recess such
`that said light source resides at least partially within said first
`recess.
`
`3. The light emission device as recited in claim 1 wherein
`said first lead frame segment comprises a second recess such
`that said epoxy cast is anchored to said first lead frame
`segment.
`4. The light emission device as recited in claim 2 wherein
`said first recess is a reflector cup.
`5. The light emission device as recited in claim 1 wherein
`said epoxy cast comprises a shaped epoxy portion.
`6. The light emission device as recited in claim 1 wherein
`said lead frame comprises plating.
`7. The light emission device as recited in claim 1 wherein
`said epoxy cast comprises a color tinting.
`8. The light emission device as recited in claim 1 wherein
`said epoxy cast is operable to diffuse light from said light
`source.
`9. The light emission device as recited in claim 1 further
`comprising a second wire bond coupled to said first lead
`frame segment and said light source.
`10. The light emission device as recited in claim 5
`wherein said shaped epoxy portion is a dome shape.
`11. The light emission device as recited in claim 1 wherein
`said light source is a light emitting diode die.
`12. A method for generating a light emission device, said
`method comprising:
`
`coupling a light source to a first lead frame segment of a
`lead frame, said lead frame further comprising a second
`lead frame segment;
`
`coupling a wire bond to said light source and said second
`lead frame segment; and
`
`encasing said light source, said wire bond, and a portion
`of said lead frame in an epoxy cast.
`13. The method as recited in claim 12 wherein said first
`lead frame segment comprises a first recess such that said
`light source resides at least partially within said first recess.
`14. The method as recited in claim 13 wherein said first
`recess is a reflector cup.
`15. The method as recited in claim 12 wherein said
`encasing comprises forming a shaped portion of said epoxy
`cast.
`16. The method as recited in claim 12 further comprising
`dying said epoxy cast with a color tinting.
`17. The method as recited in claim 12 further comprising
`diffusing at least a portion of said translucent epoxy cast.
`18. The method as recited in claim 12 further comprising
`coupling a second wire bond to said first lead frame segment
`and said light source.
`19. The method as recited in claim 12 wherein said light
`source is a light emitting diode die.
`20. A light emission device comprising:
`
`a lead frame comprising a first lead frame segment and a
`second lead frame segment;
`
`a light emitting diode coupled to said first lead frame
`segment, said first lead frame segment comprising a
`first recess such that said light source resides at least
`partially within said first recess;
`
`a wire bond coupled to said light source and coupled to
`said second lead frame segment; and
`
`an epoxy cast encasing said light emitting diode, said wire
`bond, and a portion of said lead frame, said epoxy cast
`comprising a shaped epoxy portion.
`
`VIZIO Ex. 1020 Page 00011
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`US 2005/0151149 Al
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`Jul. 14, 2005
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`5
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`21. The light em1ss10n device as recited in claim 20
`wherein said first lead frame segment comprises a second
`recess such that said epoxy cast is anchored to said first lead
`frame segment.
`22. The light emission device as recited m claim 20
`wherein said first recess is a reflector cup.
`23. The light emission device as recited in claim 20
`wherein said shaped epoxy portion is incident to said light
`source.
`24. The light emission device as recited in claim 20
`wherein said lead frame comprises plating.
`
`25. The light em1ss10n device as recited in claim 20
`wherein said epoxy cast comprises a color tinting.
`26. The light emission device as recited in claim 20
`wherein said epoxy cast is operable to diffuse light from said
`light source.
`27. The light emission device as recited in claim 20
`further comprising a second wire bond coupled to said first
`lead frame segment and said light source.
`28. The light emission device as recited in claim 20
`wherein said shaped epoxy portion is a dome shape.
`* * * * *
`
`VIZIO Ex. 1020 Page 00012
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