1. Field of the Invention
The present invention relates to semiconductor packaging, and more particularly to a semiconductor package with an electrically-conductive strap for power applications.
2. Description of the Related Art
Integrated circuit die are conventionally enclosed in plastic packages that provide protection from hostile environments and enable electrical interconnection between the integrated circuit die and printed circuit boards. The package elements may include, for example, a metal leadframe, a die, bonding material to attach the die to the leadframe, bond wires that electrically connect pads on the die to individual leads of the leadframe. A hardened plastic encapsulant material typically covers the die, the bond wires, at least a portion of the leadframe, and forms the exterior of the package.
The leadframe is typically the central supporting structure of such a package. A portion of the leadframe is internal to the package. That is, the plastic encapsulant material conventionally surrounds a central portion of the leadframe with lead portions of the leadframe extending externally outward from the sides of the package. The externally extending lead portions may be used to connect the package to external circuitry.
In conventional eight-lead, small outline integrated circuit (“SOIC-8”) high-power metal-oxide-semiconductor field effect transistor (“PMOSFET”) packages, the sources and drains of the individual transistor devices of the PMOSFET are typically connected in parallel by respective thin layers of metal on the opposed surface of the die, which, in turn, are electrically coupled to the leads of the package. This thin layer of metal, in turn, is externally connected to each of three leads of the package.
In conventional versions of this type of package, the conductive layer spanning the sources of the individual transistor devices are connected to the leads (or an intermediate structure) of a package substrate by a relatively large number (typically 14) of parallel bond wires. However, these wires have contributed to a number of problems associated with this type of device, including relatively high internal thermal and electrical resistances.
More recently, it has been learned that at least some of the foregoing problems can be alleviated by replacing the large number of bond wires with a single, elongated conductive strap that connects the thin layer of metal on top of the die to the source leads of the substrate. This approach, however, has also been somewhat problematic due to the inability of this design to effectively dissipate heat generated by the die. Accordingly, a need exists to provide a semiconductor package that provides for greater, or improved, heat dissipation capabilities.
A semiconductor package is provided that includes a die pad with a semiconductor die disposed thereon and a plurality of leads electrically coupled to the die via a conductive strap. Each of the leads has opposing first and second surfaces. An encapsulant material encapsulates the die, at least a portion of the die pad, at least a portion of the strap, and at least a portion of lead first surfaces. Second surfaces of the leads may be exposed in a plane of a horizontal exterior surface of the encapsulant, thereby permitting external electrical connectivity to the package and dissipation of heat through the lead second surfaces. A surface of the die pad and/or leads connected to the die pad also may be exposed at the horizontal exterior package surface. The exposed surfaces of the die pad and leads may be adjacent to or surrounded by recessed surfaces that are under-filled by the encapsulant material and are thus locked to the encapsulant material.
In one embodiment, a portion of the conductive strap is exposed through, and may be substantially flush with, a horizontal exterior surface of the encapsulant material opposite the die pad and leads. The exposed lead surfaces, the exposed portion of the conductive strap, and the exposed portion of the die pad provide multiple thermal paths for dissipation of heat generated by the die to the external environment.
A power MOSFET embodiment of the package conforms to a standard eight-lead small outline integrated circuit (SOIC-8) package style and has better heat dissipation capabilities than conventional SOIC-8 packages. In addition, because the leads and die pad are in the plane of the horizontal exterior surface, the package is very thin.
The present invention is best understood by reference to the following detailed description when read in conjunction with the accompanying drawings.
Common reference numerals are used throughout the drawings and detailed description to indicate like elements.
The present application has some relation to semiconductor packages and methods disclosed in U.S. patent application Ser. Nos. 09/536,236, 09/587,136, 09/816,852, and 09/733,148, all of which are expressly incorporated herein by reference in their respective entireties. The present invention may be applied to some or all of the semiconductor packages disclosed in these applications. Further, the assembly methods disclosed in these applications may be modified in accordance with the present invention.
The die pad 104 has a first surface 124 (
The transverse surface 130 of the recessed portion 127 may be substantially parallel with the first and second surfaces 124 and 126 of the die pad 104 and may be substantially perpendicular to the lateral edge surface 128. The recessed portion 127 may be formed by techniques such as etching, coining, stamping, or the like. During molding, encapsulant material 194 is permitted to enter into and generally under-fill the recessed portion 127 to secure the die pad 104 within the package 100 while permitting the second surface 126 of the die pad 104 to be exposed through lower horizontal second surface 198 of the encapsulant material 194 for external electrical connection.
The leads 106 each have opposing first and second surfaces 134 and 136, which are generally parallel to each other. The second surface 136 of each lead 106 extends between and intersects a corresponding external lateral edge 138 and a corresponding internal lateral edge 140. The internal lateral edge 140 and a corresponding transverse surface 142 are generally orthogonal and define a recessed portion 143 adjacent the second surface 136 of each of the leads 106. In one embodiment, the leads 106 are drain leads, in that they are electrically coupled to the drain terminal of PMOSFET semiconductor die 102.
During molding, the encapsulant material 194 is permitted to enter into and generally under-fill the recessed portion 143 of each of the leads 106 to secure the leads 106 within the package 100 while permitting the second surfaces 136 of the leads 106 to be exposed through the lower horizontal second surface 198 of the encapsulant material 194 for external electrical connection.
The lead 114 (
The inner edge 136b of exposed second surface 136 of leads 106 and the inner edge 146b of exposed surface 146 of lead 114 is rounded, which can facilitate the encapsulation process, help avoid delamination, and reduce stress concentration points. Corners of exposed second surface 126 of die pad 104 may be rounded for the same reasons.
The leads 116, 118, 120 (
The outer edges 136a, 146a, 116a, 118a, and 120a of leads 106, 114, and 116, 118, and 120, respectively, are generally orthogonal and, in this embodiment, extend slightly beyond the tapered sidewalls 195 of encapsulant material 194. Typically, the outer edges 136a, 146a, 116a, 118a, and 120a are formed by severing the leads from a leadframe, such as with a punch or saw.
The die 102, which may comprise a PMOSFET device, is mounted on the first surface 124 of the die pad 104. The die 102 includes opposing first and second surfaces 162 and 163, which may be substantially parallel to each other. The second surface 163 of the die 102 is mounted on the first surface 124 of the die pad 104 with metal solder, an electrically conductive die attach adhesive, or other conventional conductive die attach means. In one embodiment, the leads 116, 118, 120 are source leads in that they are integrally coupled with die pad 104, which, in turn, is electrically coupled to the source terminal of a PMOSFET die 102.
The strap 122 is formed of an electrically conductive material, such as stamped copper or an alloy thereof, and includes a planar uppermost cover portion 170 disposed between and formed integrally with an inclined first connection portion 172 and an inclined second connection portion 174. The strap 122 also includes a flange portion 176 formed integrally with the second connection portion 174 of the strap 122. The flange portion 176 of the strap 122 is mounted on and is electrically and thermally coupled to the first surface 162 of the die 102 by a conductive layer 177, such as solder or an electrically conductive adhesive epoxy. The strap 122 also includes at least one horizontally extending peripheral foot 180 formed integrally with the first connection portion 172 of the strap 122. Foot 180 is mounted on, and is thermally and electrically coupled to first surface 134 of the leads 106. The strap 122 is adhered to the leads 106 and to the die 102 by solder or an epoxy-based adhesive that is both thermally and electrically conductive. Additional details regarding the manner in which the root 180 may be coupled to the leads 106 are described below with reference to
The flange portion 176 is substantially planar and has a lip 182 formed along side and end edges thereof. As shown, the lip 182 extends vertically away from the first surface 162 of the die 102 to create a space between the lip 182 and the first surface 162 of the die 102. Typically, a layer of conductive adhesive material, which is the epoxy 177 in this example, is disposed between the flange portion 176 and the first surface 162 of the die 102 to secure the flange portion 176 to the first surface 162 of the die 102. In this configuration, the epoxy 177 is substantially thicker between the lip 182 and first surface 162 of the die 102 than between the first surface 162 of the die 102 and other areas of the flange portion 176. The thicker epoxy between the lip 182 and first surface 162 of the die 102 aids in alleviating high stress regions around the edges of the flange portion 176.
The cover portion 170 of the strap 122 is substantially planar and includes first and second surfaces 186 and 188, respectively, and has a through hole 190 formed therein. The through hole 190 extends between the first and second surfaces 186 and 188 of the cover portion 170 and is defined by a sidewall 192. As shown in
The through hole 190 is useful during the process of molding the encapsulant material 194 about the package components. The through hole 190 permits passage of molten encapsulant material 194 from adjacent the first surface 186 of the cover portion 170 through the through hole 190 and into a region adjacent the second surface 188 of the cover portion 170. Permitting the molten encapsulant material 194 to pass through the hole 190 also helps prevent the strap 122 from being disconnected during the molding process. A portion of the encapsulant material 194 fills the through hole 190.
The first surface 186 of the cover portion 170 is generally defined by a peripheral edge 189 and may be generally rectangular. As illustrated in
The encapsulant material 194 is at least partially molded about the aforementioned structures for insulation and protection and includes opposing horizontal exterior first and second surfaces 196 and 198. The first surface 196 of the encapsulant material 194 includes, and is generally defined by, a peripheral corner 197. The encapsulant material 194 also includes sidewalls 195, which taper from a corner 199 to the peripheral corner 197.
The first surface 186 of the cover portion 170 around the through hole 190 is not covered by the encapsulant material 194, but is exposed in and substantially coplanar and flush with the first surface 196 of the encapsulant material 194. The first surface 186 of the cover portion 170 radiates heat effectively to the exterior, since the first surface 186 is not covered with the encapsulant material 194. Such heat is typically generated at the die 102 and conducted through a thermal path including the flange portion 176 and the connection portion 174 of the strap 122 to the first surface 186 of the cover portion 170, where the heat may be dissipated from the first surface 186, such as by radiation.
Optionally, heat sink structures (not shown), including vertical protrusions, such as heat fins, heat pins, and the like may be attached to, or formed on, the first surface 186 of the cover portion 170 to provide additional heat dissipation capability to the package 100. The heat sink structures may be secured on the sow first surface 186 by a thermally conductive adhesive or thermal grease, for example.
As mentioned, the second surface 126 of the die pad 104 and the second surfaces 160 of the leads 116, 118, and 120 are exposed through the second surface 198 of the encapsulant material 194. In one embodiment, the exposed surfaces 126 and 160 are substantially coplanar and flush with the second surface 198 of the encapsulant material 194. The exposed second surface 126 of the die pad 104 and the second surfaces 160 of the leads 116, 118, and 120 (
Additionally, the second surfaces 136 of the leads 106 are exposed through the second surface 198 of the encapsulant material 194. In one embodiment, the exposed second surfaces 136 are substantially coplanar and flush with the second surface 198 of the encapsulant material 194. The exposed second surfaces 136 radiate heat effectively to the exterior. Such heat is typically generated at the die 102 and conducted through a thermal path including the flange portion 176, connection portion 174, cover portion 170, connection portion 172, foot 180, and through the leads 106 to be radiated to the exterior via the exposed second surfaces 136. Further, heat from the die 102 may also be dissipated through the second surface 146 of the lead 114, which may be electrically and thermally coupled to the die 102.
Accordingly, this embodiment provides for multiple thermal paths for dissipation of heat generated at the die 102. Heat may be dissipated through the following exposed surfaces: the first surface 186 of the cover portion 170 of the strap 122, the second surface 126 of the die pad 104, the second surfaces 136 of the leads 106, the second surface 146 of the lead 114, and the second surfaces 160 of the leads 116-120, among other possibilities.
In an alternative embodiment, PMOSFET die 102 is inverted, so that the drain terminal of the die 102 may be electrically coupled to first surface 124 of die pad 104, and the source terminal of the die 102 is electrically coupled by the strap 122 to the leads 106. A bond wire (not shown) may be used to electrically couple the lead 146 to the gate terminal of the die 102.
Depending on the type of die 102, the lead 146 may be omitted, for instance, where the die 102 is a diode.
Package 700 provides multiple thermal paths for dissipation of heat generated at the die 102. Heat may be dissipated through the following exposed surfaces: the first surface 186 (
At least a portion, or all, of the foot 180 of the strap 122 is disposed within the recess 1102, depending on the relative depth of the recess 1102 and thickness of the foot 108. The transverse surface 1104 of the foot 180 may be positioned adjacent or against the recess floor 1104 as shown in
The recess 1102 of FIG. 11 and the apertures 1202 and 1204 of
This disclosure provides exemplary embodiments of the present invention. The scope of the present invention is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for by the specification or implied by the specification, such as variations in structure, dimension, type of material and manufacturing process may be implemented by one of skill in the art in view of this disclosure.
This application is a continuation of application Ser. No. 10/008,048 filed on Nov. 7, 2001, now U.S. Pat. No. 6,630,726.
Number | Name | Date | Kind |
---|---|---|---|
2596993 | Gookin | May 1952 | A |
3435815 | Forcier | Apr 1969 | A |
3734660 | Davies et al. | May 1973 | A |
3838984 | Crane et al. | Oct 1974 | A |
4054238 | Lloyd et al. | Oct 1977 | A |
4189342 | Kock | Feb 1980 | A |
4258381 | Inaba | Mar 1981 | A |
4289922 | Devlin | Sep 1981 | A |
4301464 | Otsuki et al. | Nov 1981 | A |
4332537 | Slepcevic | Jun 1982 | A |
4417266 | Grabbe | Nov 1983 | A |
4451224 | Harding | May 1984 | A |
4530152 | Roche et al. | Jul 1985 | A |
4646710 | Schmid et al. | Mar 1987 | A |
4707724 | Suzuki et al. | Nov 1987 | A |
4727633 | Herrick | Mar 1988 | A |
4737839 | Burt | Apr 1988 | A |
4756080 | Thorp, Jr. et al. | Jul 1988 | A |
4812896 | Rothgery et al. | Mar 1989 | A |
4862245 | Pashby et al. | Aug 1989 | A |
4862246 | Masuda et al. | Aug 1989 | A |
4907067 | Derryberry | Mar 1990 | A |
4920074 | Shimizu et al. | Apr 1990 | A |
4935803 | Kalfus et al. | Jun 1990 | A |
4942454 | Mori et al. | Jul 1990 | A |
4987475 | Schlesinger et al. | Jan 1991 | A |
5018003 | Yasunaga et al. | May 1991 | A |
5029386 | Chao et al. | Jul 1991 | A |
5041902 | McShane | Aug 1991 | A |
5059379 | Tsutsumi et al. | Oct 1991 | A |
5065223 | Matsuki et al. | Nov 1991 | A |
5070039 | Johnson et al. | Dec 1991 | A |
5087961 | Long et al. | Feb 1992 | A |
5091341 | Asada et al. | Feb 1992 | A |
5096852 | Hobson | Mar 1992 | A |
5118298 | Murphy | Jun 1992 | A |
5151039 | Murphy | Sep 1992 | A |
5157475 | Yamaguchi | Oct 1992 | A |
5157480 | McShane et al. | Oct 1992 | A |
5168368 | Gow, 3rd et al. | Dec 1992 | A |
5172213 | Zimmerman | Dec 1992 | A |
5172214 | Casto | Dec 1992 | A |
5175060 | Enomoto et al. | Dec 1992 | A |
5200362 | Lin et al. | Apr 1993 | A |
5200809 | Kwon | Apr 1993 | A |
5214845 | King et al. | Jun 1993 | A |
5216278 | Lin et al. | Jun 1993 | A |
5218231 | Kudo | Jun 1993 | A |
5221642 | Burns | Jun 1993 | A |
5250841 | Sloan et al. | Oct 1993 | A |
5252853 | Michii | Oct 1993 | A |
5258094 | Furui et al. | Nov 1993 | A |
5266834 | Nishi et al. | Nov 1993 | A |
5273938 | Lin et al. | Dec 1993 | A |
5277972 | Sakumoto et al. | Jan 1994 | A |
5278446 | Nagaraj et al. | Jan 1994 | A |
5279029 | Burns | Jan 1994 | A |
5294897 | Notani et al. | Mar 1994 | A |
5327008 | Djennas et al. | Jul 1994 | A |
5332864 | Liang et al. | Jul 1994 | A |
5335771 | Murphy | Aug 1994 | A |
5336931 | Juskey et al. | Aug 1994 | A |
5343076 | Katayama et al. | Aug 1994 | A |
5358905 | Chiu | Oct 1994 | A |
5365106 | Watanabe | Nov 1994 | A |
5381042 | Lerner et al. | Jan 1995 | A |
5391439 | Tomita et al. | Feb 1995 | A |
5406124 | Morita et al. | Apr 1995 | A |
5410180 | Fujii et al. | Apr 1995 | A |
5414299 | Wang et al. | May 1995 | A |
5424576 | Djennas et al. | Jun 1995 | A |
5428248 | Cha | Jun 1995 | A |
5435057 | Bindra et al. | Jul 1995 | A |
5444301 | Song et al. | Aug 1995 | A |
5452511 | Chang | Sep 1995 | A |
5454905 | Fogelson | Oct 1995 | A |
5474958 | Djennas et al. | Dec 1995 | A |
5484274 | Neu | Jan 1996 | A |
5493151 | Asada et al. | Feb 1996 | A |
5508556 | Lin | Apr 1996 | A |
5517056 | Bigler et al. | May 1996 | A |
5521429 | Aono et al. | May 1996 | A |
5528076 | Pavio | Jun 1996 | A |
5534467 | Rostoker | Jul 1996 | A |
5539251 | Iverson et al. | Jul 1996 | A |
5543657 | Diffenderfer et al. | Aug 1996 | A |
5544412 | Romero et al. | Aug 1996 | A |
5545923 | Barber | Aug 1996 | A |
5581122 | Chao et al. | Dec 1996 | A |
5592019 | Ueda et al. | Jan 1997 | A |
5592025 | Clark et al. | Jan 1997 | A |
5594274 | Suetaki | Jan 1997 | A |
5604376 | Hamburgen et al. | Feb 1997 | A |
5608267 | Mahulikar et al. | Mar 1997 | A |
5625222 | Yoneda et al. | Apr 1997 | A |
5633528 | Abbott et al. | May 1997 | A |
5639990 | Nishihara et al. | Jun 1997 | A |
5640047 | Nakashima | Jun 1997 | A |
5641997 | Ohta et al. | Jun 1997 | A |
5643433 | Fukase et al. | Jul 1997 | A |
5644169 | Chun | Jul 1997 | A |
5646831 | Manteghi | Jul 1997 | A |
5650663 | Parthasarathi | Jul 1997 | A |
5661088 | Tessier et al. | Aug 1997 | A |
5665996 | Williams et al. | Sep 1997 | A |
5673479 | Hawthorne | Oct 1997 | A |
5683806 | Sakumoto et al. | Nov 1997 | A |
5689135 | Ball | Nov 1997 | A |
5696666 | Miles et al. | Dec 1997 | A |
5701034 | Marrs | Dec 1997 | A |
5703407 | Hori | Dec 1997 | A |
5710064 | Song et al. | Jan 1998 | A |
5723899 | Shin | Mar 1998 | A |
5736432 | Mackessy | Apr 1998 | A |
5745984 | Cole, Jr. et al. | May 1998 | A |
5753532 | Sim | May 1998 | A |
5753977 | Kusaka et al. | May 1998 | A |
5766972 | Takahashi et al. | Jun 1998 | A |
5770888 | Song et al. | Jun 1998 | A |
5776798 | Quan et al. | Jul 1998 | A |
5783861 | Son | Jul 1998 | A |
5801440 | Chu et al. | Sep 1998 | A |
5814877 | Diffenderfer et al. | Sep 1998 | A |
5814881 | Alagaratnam et al. | Sep 1998 | A |
5814883 | Sawai et al. | Sep 1998 | A |
5814884 | Davis et al. | Sep 1998 | A |
5817540 | Wark | Oct 1998 | A |
5818105 | Kouda | Oct 1998 | A |
5821457 | Mosley et al. | Oct 1998 | A |
5821615 | Lee | Oct 1998 | A |
5834830 | Cho | Nov 1998 | A |
5835988 | Ishii | Nov 1998 | A |
5844306 | Fujita et al. | Dec 1998 | A |
5856911 | Riley | Jan 1999 | A |
5859471 | Kuraishi et al. | Jan 1999 | A |
5866939 | Shin et al. | Feb 1999 | A |
5871782 | Choi | Feb 1999 | A |
5874784 | Aoki et al. | Feb 1999 | A |
5877043 | Alcoe et al. | Mar 1999 | A |
5886397 | Ewer | Mar 1999 | A |
5886398 | Low et al. | Mar 1999 | A |
5894108 | Mostafazadeh et al. | Apr 1999 | A |
5897339 | Song et al. | Apr 1999 | A |
5900676 | Kweon et al. | May 1999 | A |
5903049 | Mori | May 1999 | A |
5903050 | Thurairajaratnam et al. | May 1999 | A |
5909053 | Fukase et al. | Jun 1999 | A |
5915998 | Stidham et al. | Jun 1999 | A |
5917242 | Ball | Jun 1999 | A |
5939779 | Kim | Aug 1999 | A |
5942794 | Okumura et al. | Aug 1999 | A |
5951305 | Haba | Sep 1999 | A |
5959356 | Oh | Sep 1999 | A |
5969426 | Baba et al. | Oct 1999 | A |
5973388 | Chew et al. | Oct 1999 | A |
5976912 | Fukutomi et al. | Nov 1999 | A |
5977613 | Takata et al. | Nov 1999 | A |
5977615 | Yamaguchi et al. | Nov 1999 | A |
5977630 | Woodworth et al. | Nov 1999 | A |
5981314 | Glenn et al. | Nov 1999 | A |
5986333 | Nakamura | Nov 1999 | A |
5986885 | Wyland | Nov 1999 | A |
6001671 | Fjelstad | Dec 1999 | A |
6013947 | Lim | Jan 2000 | A |
6018189 | Mizuno | Jan 2000 | A |
6020625 | Qin et al. | Feb 2000 | A |
6025640 | Yagi et al. | Feb 2000 | A |
6031279 | Lenz | Feb 2000 | A |
RE36613 | Ball | Mar 2000 | E |
6034423 | Mostafazadeh | Mar 2000 | A |
6040626 | Cheah et al. | Mar 2000 | A |
6043430 | Chun | Mar 2000 | A |
6060768 | Hayashida et al. | May 2000 | A |
6060769 | Wark | May 2000 | A |
6072228 | Hinkle et al. | Jun 2000 | A |
6075284 | Choi et al. | Jun 2000 | A |
6081029 | Yamaguchi | Jun 2000 | A |
6084310 | Mizuno et al. | Jul 2000 | A |
6087722 | Lee et al. | Jul 2000 | A |
6100594 | Fukui et al. | Aug 2000 | A |
6113473 | Costantini et al. | Sep 2000 | A |
6118174 | Kim | Sep 2000 | A |
6118184 | Ishio et al. | Sep 2000 | A |
RE36907 | Templeton, Jr. et al. | Oct 2000 | E |
6130115 | Okumura et al. | Oct 2000 | A |
6130473 | Mostafazadeh et al. | Oct 2000 | A |
6133623 | Otsuki et al. | Oct 2000 | A |
6140154 | Hinkle et al. | Oct 2000 | A |
6143981 | Glenn | Nov 2000 | A |
6169329 | Farnworth et al. | Jan 2001 | B1 |
6177718 | Kozono | Jan 2001 | B1 |
6181002 | Juso et al. | Jan 2001 | B1 |
6184465 | Corisis | Feb 2001 | B1 |
6194777 | Abbott et al. | Feb 2001 | B1 |
6197615 | Song et al. | Mar 2001 | B1 |
6198171 | Huang et al. | Mar 2001 | B1 |
6201186 | Daniels et al. | Mar 2001 | B1 |
6201292 | Yagi et al. | Mar 2001 | B1 |
6204554 | Ewer et al. | Mar 2001 | B1 |
6208020 | Minamio | Mar 2001 | B1 |
6208021 | Ohuchi et al. | Mar 2001 | B1 |
6208023 | Nakayama et al. | Mar 2001 | B1 |
6211462 | Carter, Jr. et al. | Apr 2001 | B1 |
6218731 | Huang et al. | Apr 2001 | B1 |
6222258 | Asano et al. | Apr 2001 | B1 |
6225146 | Yamaguchi et al. | May 2001 | B1 |
6229200 | Mclellan et al. | May 2001 | B1 |
6229205 | Jeong et al. | May 2001 | B1 |
6239384 | Smith et al. | May 2001 | B1 |
6242281 | Mclellan et al. | Jun 2001 | B1 |
6256200 | Lam et al. | Jul 2001 | B1 |
6258629 | Niones et al. | Jul 2001 | B1 |
6281566 | Magni | Aug 2001 | B1 |
6281568 | Glenn et al. | Aug 2001 | B1 |
6282095 | Houghton et al. | Aug 2001 | B1 |
6285075 | Combs et al. | Sep 2001 | B1 |
6291271 | Lee et al. | Sep 2001 | B1 |
6291273 | Miyaki et al. | Sep 2001 | B1 |
6294100 | Fan et al. | Sep 2001 | B1 |
6294830 | Fjelstad | Sep 2001 | B1 |
6295977 | Ripper et al. | Oct 2001 | B1 |
6297548 | Moden et al. | Oct 2001 | B1 |
6303984 | Corisis | Oct 2001 | B1 |
6303997 | Lee | Oct 2001 | B1 |
6307272 | Takahashi et al. | Oct 2001 | B1 |
6309909 | Ohgiyama | Oct 2001 | B1 |
6316838 | Ozawa et al. | Nov 2001 | B1 |
6323550 | Martin et al. | Nov 2001 | B1 |
6326243 | Suzuya et al. | Dec 2001 | B1 |
6326244 | Brooks et al. | Dec 2001 | B1 |
6326678 | Karnezos et al. | Dec 2001 | B1 |
6335564 | Pour | Jan 2002 | B1 |
6339255 | Shin | Jan 2002 | B1 |
6348726 | Bayan et al. | Feb 2002 | B1 |
6355502 | Kang et al. | Mar 2002 | B1 |
6369454 | Chung | Apr 2002 | B1 |
6373127 | Baudouin et al. | Apr 2002 | B1 |
6380048 | Boon et al. | Apr 2002 | B1 |
6384472 | Huang | May 2002 | B1 |
6388336 | Venkateshwaran et al. | May 2002 | B1 |
6395578 | Shin et al. | May 2002 | B1 |
6400004 | Fan et al. | Jun 2002 | B1 |
6414385 | Huang et al. | Jul 2002 | B1 |
6420779 | Sharma et al. | Jul 2002 | B1 |
6429508 | Gang | Aug 2002 | B1 |
6437429 | Su et al. | Aug 2002 | B1 |
6444499 | Swiss et al. | Sep 2002 | B1 |
6448633 | Yee et al. | Sep 2002 | B1 |
6452279 | Shimoda | Sep 2002 | B2 |
6464121 | Reijnders | Oct 2002 | B2 |
6476469 | Hung et al. | Nov 2002 | B2 |
6476474 | Hung | Nov 2002 | B1 |
6482680 | Khor et al. | Nov 2002 | B1 |
6498099 | McLellan et al. | Dec 2002 | B1 |
6498392 | Azuma | Dec 2002 | B2 |
6507096 | Gang | Jan 2003 | B2 |
6507120 | Lo et al. | Jan 2003 | B2 |
6534849 | Gang | Mar 2003 | B1 |
6559525 | Huang | May 2003 | B2 |
6566164 | Glenn et al. | May 2003 | B1 |
6566168 | Gang | May 2003 | B2 |
6630726 | Crowley et al. | Oct 2003 | B1 |
20010008305 | McClellan et al. | Jul 2001 | A1 |
20010014538 | Kwan et al. | Aug 2001 | A1 |
20020011654 | Kimura | Jan 2002 | A1 |
20020024122 | Jung et al. | Feb 2002 | A1 |
20020027297 | Ikenaga et al. | Mar 2002 | A1 |
20020140061 | Lee | Oct 2002 | A1 |
20020140068 | Lee et al. | Oct 2002 | A1 |
20020163015 | Lee et al. | Nov 2002 | A1 |
20030030131 | Lee et al. | Feb 2003 | A1 |
20030073265 | Hu et al. | Apr 2003 | A1 |
Number | Date | Country |
---|---|---|
19734794 | Aug 1997 | DE |
5421117 | Jun 1979 | EP |
5950939 | Mar 1984 | EP |
0393997 | Oct 1990 | EP |
0459493 | Dec 1991 | EP |
0720225 | Mar 1996 | EP |
07200234 | Mar 1996 | EP |
0794572 | Oct 1997 | EP |
0844665 | May 1998 | EP |
0936671 | Aug 1999 | EP |
098968 | Mar 2000 | EP |
1032037 | Aug 2000 | EP |
55163868 | Dec 1980 | JP |
5745959 | Mar 1982 | JP |
58160095 | Aug 1983 | JP |
59208756 | Nov 1984 | JP |
59227143 | Dec 1984 | JP |
60010756 | Jan 1985 | JP |
60116239 | Aug 1985 | JP |
60195957 | Oct 1985 | JP |
60231349 | Nov 1985 | JP |
6139555 | Feb 1986 | JP |
629639 | Jan 1987 | JP |
63067762 | Mar 1988 | JP |
63205935 | Aug 1988 | JP |
63233555 | Sep 1988 | JP |
63249345 | Oct 1988 | JP |
63316470 | Dec 1988 | JP |
64054749 | Mar 1989 | JP |
1106456 | Apr 1989 | JP |
1175250 | Jul 1989 | JP |
1251747 | Oct 1989 | JP |
3177060 | Aug 1991 | JP |
4098864 | Mar 1992 | JP |
5129473 | May 1993 | JP |
5166992 | Jul 1993 | JP |
5283460 | Oct 1993 | JP |
692076 | Apr 1994 | JP |
6140563 | May 1994 | JP |
6260532 | Sep 1994 | JP |
7297344 | Nov 1995 | JP |
7312404 | Nov 1995 | JP |
864634 | Mar 1996 | JP |
8083877 | Mar 1996 | JP |
8125066 | May 1996 | JP |
8222682 | Aug 1996 | JP |
8306853 | Nov 1996 | JP |
98205 | Jan 1997 | JP |
98206 | Jan 1997 | JP |
98207 | Jan 1997 | JP |
992775 | Apr 1997 | JP |
9293822 | Nov 1997 | JP |
10022447 | Jan 1998 | JP |
10163401 | Jun 1998 | JP |
10199934 | Jul 1998 | JP |
10256240 | Sep 1998 | JP |
00150765 | May 2000 | JP |
556398 | Oct 2000 | JP |
2001060648 | Mar 2001 | JP |
200204397 | Aug 2002 | JP |
941979 | Jan 1994 | KR |
9772358 | Nov 1997 | KR |
100220154 | Jun 1999 | KR |
0049944 | Jun 2002 | KR |
9956136 | Nov 1999 | WO |
9967821 | Dec 1999 | WO |
Number | Date | Country | |
---|---|---|---|
Parent | 10008048 | Nov 2001 | US |
Child | 10618192 | US |