Title of Invention

"SOLID METAL BLOCK MOUNTING SUBSTRATES FOR SEMICONDUCTOR LIGHT EMITTING DEVICES, AND OXIDIZING METHODS FOR FABRICATING SAME"

Abstract A mounting substrate for a semiconductor light emitting device (150) includes a solid metal block (100) having a cavity (110) in a face thereof that is configured for mounting a semiconductor light emitting device (150) therein. An insulating coating (120) is provided in the cavity, and first (130a) and second (130b) spaced apart conductive traces are provided on the insulating coating (120) in the cavity (110) that are configured for connection to a semiconductor light emitting device (150). The mounting substrate may be fabricated by providing a solid aluminum block (100) including a cavity (110) in a face thereof that is configured for mounting a semiconductor light emitting device (150) therein. The solid aluminum block (100) is oxidized to form an aluminum oxide coating (120) thereon. The first (130a) and second (130b) spaced apart electrical traces are fabricated on the aluminum oxide coating (120) in the cavity (110). Fig. 1H
Full Text SOLID METAL BLOCK MOUNTING SUBSTRATES FOR
SEMICONDUCTOR LIGHT EMITTING DEVICES, AND OXIDIZING
METHODS FOR FABRICATING SAME
Field of the Invention
This invention relates to semiconductor light emitting devices and fabricating methods therefor, and more particularly to packaging and packaging methods for semiconductor light emitting devices.
Background of the Invention
Semiconductor light emitting devices, such as Light Emitting Diodes (LEDs) or laser diodes are widely used for many applications. As is well known to those having skill in the art, a semiconductor light emitting device includes one or more semiconductor layers that are configured to emit coherent and/or incoherent light upon energization thereof. It is also known that the semiconductor light emitting device generally is packaged to provide external electrical connections, heat sinking, lenses or waveguides, environmental protection and/or other functions.
For example, it is known to provide a two-piece package for a semiconductor light emitting device wherein the semiconductor light emitting device is mounted on a substrate that comprises alumina, aluminum nitride and/or other materials, which include electrical traces thereon, to provide external connections for the semiconductor light emitting device. A second substrate which may comprise silver plated copper, is mounted on the first substrate, for example using glue, surrounding the semiconductor light emitting device. A. lens may be placed on the second substrate over the semiconductor light emitting device. Light emitting diodes with two-piece packages as described above are described in Application Serial No. 10/446,532 to Loh, entitled Power Surface Mount Light Emitting Die Package, filed May 27,2003, assigned to the assignee of the present invention, the disclosure of which is hereby incorporated herein by reference in its entirety as if set forth fully herein.
Unfortunately, these substrates may be costly and, in some case, more costly than the semiconductor light emitting device themselves. Moreover, the fabrication

process may also be costly, time consuming and/or subject to failures due to the number of steps therein.
Summary of the Invention
Some embodiments of the present invention provide a mounting substrate for a semiconductor light emitting device that comprises a solid metal block including a cavity in a face thereof that is configured for mounting a semiconductor light emitting device therein. In other embodiments, an insulating coating is provided on a surface of the solid metal block. In still other embodiments, the insulating coating is in the cavity, and first and second spaced apart conductive traces are provided on the insulating coating in the cavity that are configured for connection to a semiconductor light emitting device.
In some embodiments, the first and second spaced apart conductive traces extend from the cavity to the first face around at least one side of the metal block and onto a second, opposite face of the metal block. In other embodiments, the solid metal block includes therein first and second through holes that extend from the first face to the second face of the metal block. A respective through hole includes a respective conductive via therein that extends from the first face to the second face. A respective one of the spaced apart conductive traces is electrically connected to a respective one of the conductive vias.
In some embodiments, the solid metal block is a solid aluminum block, and the insulating coating comprises aluminum oxide. The insulating coating may be formed by oxidizing the aluminum as will be described below. In these embodiments, the respective first and second through holes also include an insulating coating thereon that comprises aluminum oxide, so that the first and second conductive vias therein are insulated from the aluminum block.
Mounting substrates according "to embodiments of the present invention may be combined with a semiconductor light emitting device that is mounted in the cavity and is connected to the first and second spaced apart conductive traces. A lens may be provided that extends across the cavity. In some embodiments, an encapsulant is provided between the semiconductor light emitting device and the lens. In other embodiments, a lens retainer may be provided on the substrate that is configured to hold the lens across the cavity.

Other embodiments of the present invention fabricate a mounting substrate for a semiconductor light emitting device by providing a solid aluminum block including a cavity in a face thereof that is configured for mounting a semiconductor light emitting device therein. The solid aluminum block is oxidized to form an aluminum oxide coating thereon. First and second spaced apart electrical traces are fabricated on the aluminum oxide coating in the cavity and are configured for connection of a semiconductor light emitting device thereto.
In some embodiments, the aluminum block also includes first and second through holes that extend therethrough. The first and second through holes are oxidized when oxidizing the second aluminum block, to form an aluminum oxide coating in the first and second through holes. First and second conductive vias are fabricated in the respective first and second through holes that are coated with aluminum oxide. In other embodiments, when fabricating the first and second spaced apart conductive traces, the traces are fabricated to extend from the cavity to the first face around at least one side of the metal block and onto a second face of the metal block that is opposite the first face.
In some embodiments, a semiconductor light emitting device is mounted in the cavity and connected to the first and second spaced apart conductive traces. In some embodiments, a lens is mounted across the cavity and, in some embodiments, an encapsulant is provided between the semiconductor light emitting device and the lens.
Brief Description of the Drawings
Figures 1A-1H are side cross-sectional views of mounting substrates for semiconductor light emitting devices according to various embodiments of the present invention.
Figure 2 is a flowchart of steps that may be performed to fabricate mounting substrates for semiconductor light emitting devices according to various embodiments of the present invention.
Figures 3 A and 3B are top and bottom perspective views of a mounting substrate for semiconductor light emitting devices according to embodiments of the present invention.
Figure 4 is an exploded perspective view of a packaged semiconductor light emitting device according to embodiments of the present invention.

Figure 5 is an assembled perspective view of a packaged semiconductor light emitting device according to embodiments of the present invention.
Detailed Description
The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout.
It will be understood that when an element such as a layer, region or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. It will be understood that if part of an element, such as a surface of a conductive line, is referred to as "outer," it is closer to the outside of the device than other parts of the element. Furthermore, relative terms such as "beneath" may be used herein to describe a relationship of one layer or region to another layer or region relative to a substrate or base layer as illustrated in the figures. It will be understood that these terms are intended to encompass different orientations of the device hi addition to the orientation depicted hi the figures. Finally, the term "directly" means that there are no intervening elements.
Figures 1A-1H are side cross-sectional views of mounting substrates for semiconductor light emitting devices according to various embodiments of the present invention. Referring to Figure 1 A, mounting substrates for semiconductor light emitting devices according to some embodiments of the invention include a solid metal block 100 including a cavity 110 in a first face lOOa thereof, that is configured for mounting a semiconductor light emitting device therein. In some embodiments, the solid metal block 100 comprises a solid aluminum block. The cavity 110 may be formed by machining, coming, etching and/or other conventional techniques. The size and shape of the cavity 110 may be configured to improve or optimize the amount and/or direction of light that is emitted by a semiconductor light emitting device that is mounted in the cavity 110. For example, oblique sidewalls llOa and or a semi-ellipsoidal cross-sectional profile may be provided. In some embodiments, the

metal block 100 may be a rectangular solid metal block of aluminum about 6min x about 9mm, and about 2mm thick, and the cavity 110 may be about 1.2mm deep with a circular floor that is about 2.5mm in diameter, with sidewalls llOa that are of any simple or complex shape to obtain desired radiation patterns. However, the block 100 may have other polygonal and/or ellipsoidal shapes.
Figure IB illustrates mounting substrates according to other embodiments of the present invention. As shown in Figure IB, an insulating coating is provided on the surface of the solid metal block 100. The insulating coating 120 may be provided on the entire exposed surface of the solid metal block as shown in Figure IB, or on only a portion of the exposed surface of the solid metal block. In some embodiments, as will be described below, the insulating coating 120 comprises a thin layer of aluminum oxide (A^Os) that may be formed, for example, by anodic oxidation of the solid aluminum block 100. In other embodiments, the coating 120 is sufficiently thick to provide an insulator, but is sufficiently thin to minimize the thermal conductive path therethrough.
Referring now to Figure 1C, first and second spaced apart conductive traces 130a, 130b are provided on the insulating coating 120 in the cavity 110. The first and second spaced apart conductive traces 130a, 130b are configured for connection to a semiconductor light emitting device. As shown in Figure 1C, in some embodiments, the first and second spaced apart conductive traces 130a and 130 b can extend from the cavity 110 onto the first face lOOa of the solid metal block 100. When the insulating coating 120 is provided on only a portion of the solid metal block 100, it" may be provided between the first and second spaced apart traces 130a and 130b and the solid metal block 100, to thereby insulate the first and second metal traces 130a and 130b from the solid metal block 100.
Figure ID illustrates other embodiments of the present invention wherein the first and second spaced apart conductive traces 130a', 130b' extend from the cavity 110 to the first face lOOa around at least one side lOOc of the metal block and onto a second face lOOb of the metal block that is opposite the first face lOOa. Thus, backside contacts may be provided.
In some embodiments of the invention, the first and second spaced apart conductive traces 130a, 130b and/or I30a1,130b' comprise metal and, in some embodiments, a reflective metal such as silver. In other embodiments, as shown in Figure IE, separate reflective layers 132a, 132b may be provided on the spaced apart

conductive traces 130a', 130b' in the cavity 110. In. these embodiments, the conductive traces 130a', 130b' may comprise copper, and the reflective traces 132a, 132b may comprise silver.
In still other embodiments of the present invention, as illustrated in Figure IF, backside contacts may be provided by providing first and second through holes 140a and 140b, which may be formed in the solid metal block 100 by machining, etching and/or other conventional techniques. Moreover, as shown in Figure IF, the insulating coating 120 extends into the through holes 140a and 140b. First and second conductive vias 142a, 142b are provided in the first and second through holes 140a, 140b, and are insulated from the solid metal block 100 by the insulating coating 120 hi through holes 140a, 140b.
In Figure IF, the through holes 140a and 149b, and the conductive vias 142a and 142b extend from the cavity 110 to the second face lOOb. The through holes 140a, 140b may be orthogonal and/or oblique to the first and second faces lOOa, lOOb. First and second spaced apart conductive traces 130a', 130b' may be provided in the cavity 110, and electrically connected to the respective first and second conductive vias 142a, 142b. On the second face lOOb, third and fourth spaced apart conductive traces 130c, 130d also may be provided that are electrically connected to the respective first and second conductive vias 142a., 142b. A solder mask layer 144 may be provided in some embodiments to isolate the third and fourth conductive traces 130c, 130d on the second face lOOb, to facilitate circuit board assembly. Solder mask layers 144 are well known to those having skill ha the art and need notbe described further herein.
In embodiments of Figure IF, the first and second through holes 140a, 140b and the first and second conductive vias 142a, 142b extended from the cavity 110 to the second face lOOb. In embodiments of Figure IGr, the first and second through holes 140af, 140b' and the first and second conductive vias 142a', 142bf extend from the first face lOOa outside the cavity 110 to the second face lOOb. The through holes 140a', 140b' may be orthogonal and/or oblique to the first and second faces lOOa, lOOb. First and second spaced apart conductive traces 130a", 130b" extend from the cavity 110 to the respective first and second conductive vias 142a', 142b' on the first face lOOa. Third and fourth traces 130c', 130d' are provided on the second face lOOb that electrically connect to the respective first and second conductive via 142a', 142b'.

Figure 1H illustrates embodiments of the invention that were described in connection with Figure ID, and which further include a semiconductor light emitting device 150 that is mounted in the cavity and that is connected to the first and second spaced apart electrical traces 130a', 130b'. Moreover, Figure 1H illustrates that in other embodiments, a lens 170 extends across the cavity. In still other embodiments, an encapsulant 160 is provided between the semiconductor light emitting device 150 and the lens 170. The encapsulant 160 may comprise clear epoxy and can enhance optical coupling from the semiconductor light emitting device 150 to the lens 170. In still other embodiments, a lens retainer 180 is provided on the solid metal block 100, to hold the lens 170 across the cavity 110.
Embodiments of light emitting devices 150, encapsulants 160 and lenses 170 that may be used in various embodiments of the present invention are described in
U.S. Patent Application Serial No. , entitled Transmissive Optical
Elements Including Transparent Plastic Shell Having a Plwsphor Dispersed Therein, and Methods of Fabricating Same, to Negley et al. (Attorney Docket No. 5308-310), filed concurrently and assigned to the assignee of the present application, the
f
disclosure of which is hereby incorporated by reference in its entirety as if set forth fully herein.
It will be understood by those having skill in the art that, although the embodiments of Figures 1F-1H have been illustrated as separate embodiments, various elements of Figures 1A-1H may be used together to provide various combinations and/or subcombinations of elements. Thus, for example, the reflective layer 132a, 132b may be used in any of the embodiments shown, and the semiconductor light emitting device 150, lens 170, encapsulant 160 and/or the lens retainer 180 may be used in any of the embodiments shown. Accordingly, the present invention should not be limited to the separate embodiments that are shown in Figures 1A-1H.
Figure 2 is a flowchart of steps that may be performed to fabricate semiconductor light emitting devices according to various embodiments of the present invention. Referring to Figure 2, as shown at Block 210, a solid aluminum block, such as aluminum block 100 of Figures 1A-1H, is provided including a cavity, such as cavity 110, in a face thereof, that is configured for mounting a semiconductor light emitting device therein. As was described above, the cavity may be provided by machining, coining, etching and/or other conventional techniques. Moreover, in other

embodiments, the solid aluminum block may also contain the first and second spaced apart through holes such as through holes 140a, 140b and/or 140a', 140b' that extend therethrough, and which may be fabricated by machining, etching and/or other conventional techniques.
Referring again to Figure 2, at Block 220, the solid aluminum block is oxidized to form an aluminum oxide coating thereon. In some embodiments, the entire exposed surface of the solid aluminum block is oxidized. Moreover, when through holes are provided, the inner surfaces of the through holes also may be oxidized. In other embodiments, only portions of the aluminum block are oxidized, for example, by providing a masking layer on those portions which are desired not to be oxidized. Oxidization of aluminum is well known to those having skill in the art
i
and may be performed, for example, using an anodic oxidation processes and/or other oxidation processes, to provide a thin layer of A^C^ on the aluminum.
Still referring to Figure 2, at Block 230, first and second spaced apart conductive traces, such as traces 130a, 130b and/or 130a', 130b', are fabricated in the cavity on the first face, on the sides and/or on the second face, depending on the configuration, as was described above. Moreover, in some embodiments, conductive vias, such as vias 142a, 142b and/or 142a', 142b' may be fabricated hi through holes. The conductive vias may be fabricated prior to, concurrent with and/or after the conductive traces. The fabrication of conductive traces on an aluminum core that is oxidized with aluminum oxide is well known to provide circuit board-like structures with an aluminum core, and accordingly need not be described in detail herein.
Finally, at Block 240, other operations are performed to mount the semiconductor device, lens, encapsulant and/or retainer on the substrate.
Figures 3 A and 3B are top and bottom perspective views, respectively, of mounting substrates according to embodiments of the present invention, which may correspond to the cross-sectional view of Figure ID. Figures 3A and 3B illustrate the solid metal block 100, the first and second spaced apart conductive traces 130 a', 130b' that wrap around the solid metal block, and the semiconductor light emitting device 150 mounted in the cavity 110. The insulating coating 120 may be transparent and is not shown. A second insulating layer and/or solder mask may be provided on the first and/or second spaced apart conductive traces in these and/or any other embodiments.

Figure 4 illustrates an exploded perspective view of other embodiments of the present invention, which may correspond to Figure 1H. As shown in Figure 4, the solid metal block 100 includes a cavity 110 therein, and a plurality of spaced apart electrical traces thereon. In Figure 4, the first electrical trace 130a is shown. However, rather than a single second electrical trace, a plurality of second electrical traces 330a', 330b' and 330c' may be provided to connect to a plurality of semiconductor light emitting devices 150' that may be mounted in the cavity 110 to provide, for example, red, green and blue semiconductor light emitting devices for a white light source. The encapsulant 160 and lens retainer 180 are shown. Other configurations of lens retainers 180 can provide a ridge and/or other conventional mounting means for mounting a lens 170 on the solid metal block 100. It also will be understood that an epoxy or other glue may be used in a lens retainer 180. The lens retainer 180 may also provide additional top heat sinking capabilities in some embodiments of the present invention. Figure 5 illustrates the assembled package of Figure 4.
Accordingly, some embodiments of the present invention use a solid block of aluminum as a mounting substrate for a semiconductor light emitting device. Aluminum has sufficient thermal conductivity to be used as an effective heat sink. Additionally, the cost of the material and the cost to fabricate can be low. Moreover, the ability to grow high quality insulating oxides allows the desired electrical traces to be formed without a severe impact on the thermal resistance, since the thickness of the anodic oxidation can be precisely controlled. This insulating layer also can be selectively patterned, which can allow the addition of another plated metal to the substrate, such as plating silver on the cavity sidewalls only, for increased optical performance.
The ability to form an optical cavity in the substrate, rather than a separate reflector cup, can reduce the assembly costs, since the total number of elements for the package can be reduced. Additionally, the fact that the reflector (cavity) position is fixed with respect to the substrate can also reduce the assembly complexity. Embodiments of the invention may be particularly useful for high power semiconductor light emitting devices such as high power LEDs and/or laser diodes.
In the drawings and specification, there have been disclosed embodiments of the invention and, although specific terms are employed, they are used in a generic

and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth hi the following claims.



We claim:
1. A mounting substrate for a semiconductor light emitting device comprising:
a solid metal block (100) that is configured for mounting a semiconductor light emitting device (150) thereon;
a conformal insulating coating (120) on a surface of the solid metal block (100); and
first (130a) and second (130b) spaced apart conductive traces on the conformal insulating coating (120) that are configured for connection to a semiconductor light emitting device (150), the first (130a) and second (130b) spaced apart conductive traces on the conformal insulating coating being further configured to reflect light that is emitted by a semiconductor light emitting device (150),
wherein the face of the solid metal block (100) is a first face (100a) and wherein the solid metal block includes therein first (140a) and second (140b) through holes that extend from the first face (100a) to a second face (100b) of the solid metal block (100) that is opposite the first face (100a), the respective first (140a) and second (140b) through holes including respective first (142a) and second (142b) conductive vias therein that are insulated from the solid metal block (100) and that extend from the first face (100a) to the second face (100b) and wherein a respective one of the spaced apart conductive traces is electrically connected to a respective one of the conductive vias on the first face (100a).
2. A mounting substrate as claimed in Claim 1, wherein the first (130a) and second (130b) spaced apart conductive traces extend from the first face (100a), around at least one side of the solid metal block (100) and onto the second face (130b) of the solid metal block (100).
3. A mounting substrate as claimed in Claim 1, wherein the solid metal block (100) is a solid aluminum block and wherein the insulating coating (120) comprises aluminum oxide.
4. A mounting substrate as claimed in Claim 3, wherein the respective first (140a) and second (140b) through holes include an insulating coating (120) thereon that comprises aluminum oxide.
5. A mounting substrate as claimed in Claim 1, further comprising third (130c) and fourth (130d) spaced apart conductive traces on the second face (100b) of the solid metal block (100), a respective one of which is connected to a respective one of the conductive vias.
6. A mounting substrate as claimed in Claim 1, in combination with a semiconductor light emitting device (150), a face of which is connected to at least one of the first (130a) and second (130b) spaced apart conductive traces.
7. A mounting substrate as claimed in Claim 6, in further combination with a lens (170) on the semiconductor light emitting element (150).
8. A mounting substrate as claimed in Claim 7, in further combination with an encapsulant (160) between the semiconductor light emitting device (150) and the lens (170).
9. A mounting substrate as claimed in Claim 7, in further combination with a lens retainer (180) on the solid metal block (100) that is configured to hold the lens (170).
10. A method of fabricating a mounting substrate for a semiconductor light emitting device comprising:
providing a solid aluminum block (100) that is configured for mounting a semiconductor light emitting device (150) thereon and first (140a) and second (140b) through holes therein that extend from the first face (100a) to a second face (100b) of the solid aluminum block (100) that is opposite the first face (100a);
oxidizing the solid aluminum block (100) to form an aluminum oxide coating (120) thereon and in the first (140a) and second (140b) through holes;
fabricating first (130a) and second (130b) spaced apart conductive traces on the aluminum oxide coating (120) that are configured for connection of a semiconductor light emitting device (150) thereto, the first (130a) and second (130b) spaced apart conductive traces on the conformal insulating coating (120) being further configured to reflect light that is emitted by a semiconductor light emitting device (150), and
fabricating respective first (142a) and second (142b) conductive vias in the respective first (140a) and second (140b) through holes that are coated with aluminum oxide and that extend from the first face (100a) to the second face (100b).
11. A method as claimed in Claim 10, wherein the fabricating first (130a) and second (130b) spaced apart conductive traces comprises fabricating first (130a) and second (130b) spaced apart conductive traces that extend from the first face (100a), around at least one side of the solid aluminum block (100) and onto a second face (100b) of the solid aluminum block (100) that is opposite the first face (100a).
12. A method as claimed in Claim 10, further comprising fabricating a reflective coating (132a, 132b) on the first (130a) and second (130b) spaced apart conductive traces on the aluminum oxide coating (120).
13. A method as claimed in Claim 10, further comprising fabricating third (130c) and fourth (130d) spaced apart conductive traces on the second face (100b) of the solid aluminum block (100), such that a respective one of the third (130c) and fourth (130d) spaced apart conductive traces on the second face (100b) is connected to a respective one of the first (142a) and second (142b) conductive vias.
14. A method as claimed in Claim 10, further comprising mounting a semiconductor light emitting device (150) on the solid aluminum block(100), such that a face of the semiconductor light emitting device (150) is connected to at least one of the first (130a) and second (130b) spaced apart conductive traces.
15. A method as claimed in Claim 14, further comprising mounting a lens (170) on the semiconductor light emitting device (150).
16. A method as claimed in Claim 15, wherein the mounting a lens (170) comprises mounting a lens (170) on the semiconductor light emitting device (150) with an encapsulant (160) between the semiconductor light emitting device (150) and the lens (170).


Documents:

1021-delnp-2006-Abstract-(07-04-2010).pdf

1021-delnp-2006-abstract.pdf

1021-delnp-2006-assignments.pdf

1021-delnp-2006-Claims-(07-04-2010).pdf

1021-delnp-2006-claims.pdf

1021-delnp-2006-Correspondence-Others-(07-04-2010).pdf

1021-delnp-2006-Correspondence-Others-(22-02-2010).pdf

1021-delnp-2006-correspondence-others-1.pdf

1021-delnp-2006-correspondence-others.pdf

1021-delnp-2006-description (complete).pdf

1021-delnp-2006-Drawings-(07-04-2010).pdf

1021-delnp-2006-drawings.pdf

1021-delnp-2006-form-1.pdf

1021-delnp-2006-form-18.pdf

1021-delnp-2006-form-2.pdf

1021-delnp-2006-Form-3-(22-02-2010).pdf

1021-delnp-2006-form-3.pdf

1021-delnp-2006-form-5.pdf

1021-delnp-2006-GPA-(07-04-2010).pdf

1021-delnp-2006-gpa.pdf

1021-delnp-2006-pct-101.pdf

1021-delnp-2006-pct-210.pdf

1021-delnp-2006-pct-220.pdf

1021-delnp-2006-pct-237.pdf

1021-delnp-2006-pct-401.pdf

1021-delnp-2006-pct-409.pdf

1021-delnp-2006-pct-416.pdf

1021-delnp-2006-pct-notification.pdf

1021-delnp-2006-Petition 137-(07-04-2010).pdf


Patent Number 248638
Indian Patent Application Number 1021/DELNP/2006
PG Journal Number 31/2011
Publication Date 05-Aug-2011
Grant Date 29-Jul-2011
Date of Filing 27-Feb-2006
Name of Patentee CREE INC.
Applicant Address 4600 SILICON DRIVE,DURHAM,NC 27703,U.S.A.
Inventors:
# Inventor's Name Inventor's Address
1 GERALD NEGLEY 306 N.ESTES DRIVE,ESTES PARK APARTMENT I-14,CARRBORO,NORTH CAROLINA 27510,U.S.A.
2 BAN LOH 8 TRESCOTT DRIVE, DURHAM, NORTH CAROLINA 27703,U.S.A.
PCT International Classification Number H01L 33/00
PCT International Application Number PCT/US2004/017326
PCT International Filing date 2004-06-01
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10/659,108 2003-09-09 U.S.A.