US20050258044A1 - Magnetic focus rings for improved copper plating - Google Patents
Magnetic focus rings for improved copper plating Download PDFInfo
- Publication number
- US20050258044A1 US20050258044A1 US10/850,648 US85064804A US2005258044A1 US 20050258044 A1 US20050258044 A1 US 20050258044A1 US 85064804 A US85064804 A US 85064804A US 2005258044 A1 US2005258044 A1 US 2005258044A1
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- US
- United States
- Prior art keywords
- magnets
- recited
- magnet
- bath chamber
- cathode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/28—Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
- H01L21/283—Deposition of conductive or insulating materials for electrodes conducting electric current
- H01L21/288—Deposition of conductive or insulating materials for electrodes conducting electric current from a liquid, e.g. electrolytic deposition
- H01L21/2885—Deposition of conductive or insulating materials for electrodes conducting electric current from a liquid, e.g. electrolytic deposition using an external electrical current, i.e. electro-deposition
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D21/00—Processes for servicing or operating cells for electrolytic coating
- C25D21/12—Process control or regulation
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/007—Electroplating using magnetic fields, e.g. magnets
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/18—Electroplating using modulated, pulsed or reversing current
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/12—Semiconductors
- C25D7/123—Semiconductors first coated with a seed layer or a conductive layer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
- H01L21/768—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
- H01L21/76838—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the conductors
- H01L21/76877—Filling of holes, grooves or trenches, e.g. vias, with conductive material
Definitions
- the present invention generally relates to methods and systems for depositing metal on a substrate, such as depositing copper on a semiconductor wafer.
- the present invention more specifically relates to the use of a magnetic filed, such as with magnetic focus rings, to improve copper plating.
- a DC source 10 is used to apply a field from a copper anode 12 to a wafer (the cathode) 14 in a plating bath chamber 16 , and Cu2+ copper ions follow field lines 18 to the surface 20 of the wafer 14 .
- a DC source 10 is used to apply a field from a copper anode 12 to a wafer (the cathode) 14 in a plating bath chamber 16 , and Cu2+ copper ions follow field lines 18 to the surface 20 of the wafer 14 .
- An object of an embodiment of the present invention is to provide a method and system which can be used to deposit copper uniformly onto a wafer.
- Another object of an embodiment of the present invention is to provide a method and system which deposits copper onto a wafer such that there is no gap fill problem.
- an embodiment of the present invention provides a method and system wherein magnets are employed proximate, such as on the outside of, a plating bath chamber to control the field lines that are used during the plating process.
- magnets are employed proximate, such as on the outside of, a plating bath chamber to control the field lines that are used during the plating process.
- the magnetic field acting on the bath can be continuous, pulsed, stressed (i.e., the shape of the field can be changed), sinusoidal, etc.
- the magnetic field can be modulated as function of time to produce a desired copper uniformity on the wafer. It is anticipated that there is no limit to how the shape of the magnets or magnetic field can be configured and controlled to achieve the desired result for both fill of deep contacts and the uniformity needed to match the subsequent polish process.
- FIG. 1 illustrates a prior art system for depositing copper on the surface of a semiconductor wafer
- FIG. 2 illustrates a system for depositing copper on the surface of a semiconductor wafer, wherein the system is in accordance with an embodiment of the present invention
- FIG. 3 provides a top view, showing magnets positioned around the circumference of the bath chamber
- FIG. 4 provides a flow chart of a method which can be used in connection with the system shown in FIG. 2 , wherein the method is in accordance with an embodiment of the present invention.
- FIG. 2 illustrates a system 30 for depositing copper on the surface 20 of a semiconductor wafer 14 , wherein the system 30 is in accordance with an embodiment of the present invention.
- the system 30 provides that magnets 32 are positioned proximate a bath housing 16 . While the magnets 32 may possibly be placed within the bath housing 16 if properly insulated, as shown in FIG. 3 preferably the magnets 32 are positioned on the outside of the bath housing 16 , around its circumference or outer perimeter 34 . Regardless, the magnets 32 are used to provide a magnetic field to improve uniformity and gap fill.
- a DC source 10 is used to apply a field from a copper anode 12 to a wafer (the cathode) 14 in a plating bath chamber 16 , and Cu2+ copper ions follow field lines 40 to the surface 20 of the wafer 14 .
- the magnets 32 are used to effectively modify the field lines 40 so that they are more linear between the anode (i.e., the copper) 12 and the cathode (i.e., the wafer) 14 (i.e., compare the field lines 18 illustrated in FIG. 1 to the field lines 40 illustrated in FIG. 2 ).
- the magnets 32 may be permanent magnets and/or controllable electro-magnets. If at least some of the magnets 32 are electro-magnets, a control system 42 is connected to the electro-magnets and is operable to modulate the magnets to provide a desired magnetic filed such that the filed lines 40 between the anode 12 and cathode 14 are tuned as desired to improve both uniformity of copper deposit and improve gap fill.
- the magnetic field acting on the bath can be continuous, pulsed, stressed (i.e. the shape of the field can be changed), sinusoidal, etc. There is no limit to how the shape of the magnets or magnetic field can be configured and controlled to achieve the desired result for both fill of deep contacts and the uniformity needed to match the polish process.
- the typical uniformity problems seen on plated wafers manifests itself as a bulls eye, center to edge pattern.
- the shape and intensity of the field lines produced by the power supply connected to the cathode and anode can be altered to produce a desired uniformity pattern on the wafer.
- the shapes of the magnetic field can also be controlled such that the intensity can be modulated at any area of the bath.
- the magnetic fields generated would force the field lines to be vertical in both the center of the wafer and at the edge of the bath allowing the migrating copper ions to arrive at the surface of the wafer “more vertical” therefore more successfully in filling the deep gaps in both the center of the wafer and the edge of the wafer.
- control system 42 is configured such that the magnetic filed is modulated over time. Improved vertical plating at the edge of the wafer is more important at the beginning of the plating process. As the contacts fill, the high aspect ratio decreases. As this happens, preferably the magnetic filed is modulated so that the field lines are changed to go from “the best fill” to the most desired uniformity to meet the needs of the polish process.
- the present invention provides that fixed or electrically controlled magnets are used in association with a plating bath chamber to control the field lines that are used during the plating process. By controlling the field lines during the plating process, improved gap fill and uniformity can be achieved. None of the currently available electroplating tools on the market utilize such a method of field line control for uniformity or gap fill improvement.
- FIG. 4 shows a flow chart of at least one embodiment of this invention.
- Box 100 explains the basic electroplating process and box 102 explains the improved copper deposition process by the utilization of a controlled magnetic field to improve deposition uniformity.
Abstract
Description
- The present invention generally relates to methods and systems for depositing metal on a substrate, such as depositing copper on a semiconductor wafer. The present invention more specifically relates to the use of a magnetic filed, such as with magnetic focus rings, to improve copper plating.
- In the semiconductor industry, copper wire interconnects are becoming the process of record for 0.13 micron processing node and smaller. The current technology used for this process is electro-chemical-deposition (ECD). Many companies manufacture tools for this process. The final copper uniformity of the deposition needs to match the uniformity of the CMP process as much as possible from center to edge before the wafer goes into the post polishing process (either chemical mechanical polishing (CMP) or electro-polishing). If the non-uniformity of the final film and polishing processes are not matched, there are problems with the devices. Another problem is gap fill. As dimensions get smaller, technology is relying more on the chemistry to assist gap fill. However, voids are still a major problem with regard to the new technologies which are being used.
- Typically, current tool designs are very similar to each other, except for differences in the design of the plating cell head which holds the wafer (and which operates as the cathode in the plating process), the cell body (which is the bath tank for the plating solution), and the anode (which is the source of the copper ions which become deposited on the wafer). In the industry, tool suppliers provide a plumbing, re-circulation, and filtration system for supplying the electrolyte solution to the surface of the wafer in the presence of an electric field. As shown in
FIG. 1 , aDC source 10 is used to apply a field from acopper anode 12 to a wafer (the cathode) 14 in aplating bath chamber 16, and Cu2+ copper ions followfield lines 18 to thesurface 20 of thewafer 14. In attempts to control the uniformity, each of the vendors that manufacture a tool for this process has designed a different cell head, a different bath structure, and different anode configurations. However, all of these designs still yield a level of non-uniformity that must be dealt with in future processing steps. Other attempts using different chemical formulations have also been devised to deal with the problems of non-uniformity of deposit and the presence of voids. - Generally, existing solutions have not solved the uniformity and gap fill problems associated with deposition of copper on a semiconductor wafer. In fact, some of the designs have introduced additional problems that are difficult to eliminate, such as edge particles caused by the contact ring, or bulk defects caused by the chemistry.
- An object of an embodiment of the present invention is to provide a method and system which can be used to deposit copper uniformly onto a wafer.
- Another object of an embodiment of the present invention is to provide a method and system which deposits copper onto a wafer such that there is no gap fill problem.
- Briefly, and in accordance with at least one of the foregoing objects, an embodiment of the present invention provides a method and system wherein magnets are employed proximate, such as on the outside of, a plating bath chamber to control the field lines that are used during the plating process. By being able to control the field lines during the plating process, improved gap fill and uniformity can be achieved.
- The magnetic field acting on the bath can be continuous, pulsed, stressed (i.e., the shape of the field can be changed), sinusoidal, etc. The magnetic field can be modulated as function of time to produce a desired copper uniformity on the wafer. It is anticipated that there is no limit to how the shape of the magnets or magnetic field can be configured and controlled to achieve the desired result for both fill of deep contacts and the uniformity needed to match the subsequent polish process.
- The organization and manner of the structure and operation of the invention, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawing, wherein:
-
FIG. 1 illustrates a prior art system for depositing copper on the surface of a semiconductor wafer; -
FIG. 2 illustrates a system for depositing copper on the surface of a semiconductor wafer, wherein the system is in accordance with an embodiment of the present invention; -
FIG. 3 provides a top view, showing magnets positioned around the circumference of the bath chamber; -
FIG. 4 provides a flow chart of a method which can be used in connection with the system shown inFIG. 2 , wherein the method is in accordance with an embodiment of the present invention. - While the invention may be susceptible to embodiment in different forms, there are shown in the drawings, and herein will be described in detail, specific embodiments of the invention. The present disclosure is to be considered an example of the principles of the invention, and is not intended to limit the invention to that which is illustrated and described herein.
-
FIG. 2 illustrates asystem 30 for depositing copper on thesurface 20 of asemiconductor wafer 14, wherein thesystem 30 is in accordance with an embodiment of the present invention. Thesystem 30 provides thatmagnets 32 are positioned proximate abath housing 16. While themagnets 32 may possibly be placed within thebath housing 16 if properly insulated, as shown inFIG. 3 preferably themagnets 32 are positioned on the outside of thebath housing 16, around its circumference orouter perimeter 34. Regardless, themagnets 32 are used to provide a magnetic field to improve uniformity and gap fill. Specifically, aDC source 10 is used to apply a field from acopper anode 12 to a wafer (the cathode) 14 in aplating bath chamber 16, and Cu2+ copper ions followfield lines 40 to thesurface 20 of thewafer 14. Themagnets 32 are used to effectively modify thefield lines 40 so that they are more linear between the anode (i.e., the copper) 12 and the cathode (i.e., the wafer) 14 (i.e., compare thefield lines 18 illustrated inFIG. 1 to thefield lines 40 illustrated inFIG. 2 ). - The
magnets 32 may be permanent magnets and/or controllable electro-magnets. If at least some of themagnets 32 are electro-magnets, acontrol system 42 is connected to the electro-magnets and is operable to modulate the magnets to provide a desired magnetic filed such that the filedlines 40 between theanode 12 andcathode 14 are tuned as desired to improve both uniformity of copper deposit and improve gap fill. The magnetic field acting on the bath can be continuous, pulsed, stressed (i.e. the shape of the field can be changed), sinusoidal, etc. There is no limit to how the shape of the magnets or magnetic field can be configured and controlled to achieve the desired result for both fill of deep contacts and the uniformity needed to match the polish process. - The typical uniformity problems seen on plated wafers manifests itself as a bulls eye, center to edge pattern. By modulating the intensity of the magnetic field, the shape and intensity of the field lines produced by the power supply connected to the cathode and anode can be altered to produce a desired uniformity pattern on the wafer. The shapes of the magnetic field can also be controlled such that the intensity can be modulated at any area of the bath. The magnetic fields generated would force the field lines to be vertical in both the center of the wafer and at the edge of the bath allowing the migrating copper ions to arrive at the surface of the wafer “more vertical” therefore more successfully in filling the deep gaps in both the center of the wafer and the edge of the wafer.
- Preferably, the
control system 42 is configured such that the magnetic filed is modulated over time. Improved vertical plating at the edge of the wafer is more important at the beginning of the plating process. As the contacts fill, the high aspect ratio decreases. As this happens, preferably the magnetic filed is modulated so that the field lines are changed to go from “the best fill” to the most desired uniformity to meet the needs of the polish process. - The present invention provides that fixed or electrically controlled magnets are used in association with a plating bath chamber to control the field lines that are used during the plating process. By controlling the field lines during the plating process, improved gap fill and uniformity can be achieved. None of the currently available electroplating tools on the market utilize such a method of field line control for uniformity or gap fill improvement.
-
FIG. 4 shows a flow chart of at least one embodiment of this invention. Box 100 explains the basic electroplating process andbox 102 explains the improved copper deposition process by the utilization of a controlled magnetic field to improve deposition uniformity. - While embodiments of the present invention are shown and described, it is envisioned that those skilled in the art may devise various modifications of the present invention without departing from the spirit and scope of the appended claims.
Claims (18)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/850,648 US20050258044A1 (en) | 2004-05-21 | 2004-05-21 | Magnetic focus rings for improved copper plating |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/850,648 US20050258044A1 (en) | 2004-05-21 | 2004-05-21 | Magnetic focus rings for improved copper plating |
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US20050258044A1 true US20050258044A1 (en) | 2005-11-24 |
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ID=35374140
Family Applications (1)
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US10/850,648 Abandoned US20050258044A1 (en) | 2004-05-21 | 2004-05-21 | Magnetic focus rings for improved copper plating |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062816A1 (en) * | 2005-09-16 | 2007-03-22 | Samsung Electro-Mechanics Co., Ltd. | Method of electroplating printed circuit board using magnetic field having periodic directionality |
US20110042223A1 (en) * | 2009-08-24 | 2011-02-24 | Ezekiel Kruglick | Magnetic Electro-Plating |
CN103160903A (en) * | 2011-12-16 | 2013-06-19 | 深圳富泰宏精密工业有限公司 | Anodization coloring apparatus and treating method of coloring by using same |
CN113493920A (en) * | 2020-03-19 | 2021-10-12 | 芯恩(青岛)集成电路有限公司 | Device and method for improving uniformity of electroplating film |
Citations (6)
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---|---|---|---|---|
US3223897A (en) * | 1963-09-23 | 1965-12-14 | Varian Associates | Apparatus for adjusting the configuration of a magnetic field |
US3386895A (en) * | 1964-11-27 | 1968-06-04 | Ibm | Method and apparatus for electroplating rollable objects |
US20020005358A1 (en) * | 2000-07-13 | 2002-01-17 | Toichi Chikuma | Electrolysis method and apparatus |
US6451195B1 (en) * | 1999-07-07 | 2002-09-17 | Nec Corporation | System and method for electrolytic plating using a magnetic field |
US6919010B1 (en) * | 2001-06-28 | 2005-07-19 | Novellus Systems, Inc. | Uniform electroplating of thin metal seeded wafers using rotationally asymmetric variable anode correction |
US7189647B2 (en) * | 2001-04-05 | 2007-03-13 | Novellus Systems, Inc. | Sequential station tool for wet processing of semiconductor wafers |
-
2004
- 2004-05-21 US US10/850,648 patent/US20050258044A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3223897A (en) * | 1963-09-23 | 1965-12-14 | Varian Associates | Apparatus for adjusting the configuration of a magnetic field |
US3386895A (en) * | 1964-11-27 | 1968-06-04 | Ibm | Method and apparatus for electroplating rollable objects |
US6451195B1 (en) * | 1999-07-07 | 2002-09-17 | Nec Corporation | System and method for electrolytic plating using a magnetic field |
US20020005358A1 (en) * | 2000-07-13 | 2002-01-17 | Toichi Chikuma | Electrolysis method and apparatus |
US7189647B2 (en) * | 2001-04-05 | 2007-03-13 | Novellus Systems, Inc. | Sequential station tool for wet processing of semiconductor wafers |
US6919010B1 (en) * | 2001-06-28 | 2005-07-19 | Novellus Systems, Inc. | Uniform electroplating of thin metal seeded wafers using rotationally asymmetric variable anode correction |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062816A1 (en) * | 2005-09-16 | 2007-03-22 | Samsung Electro-Mechanics Co., Ltd. | Method of electroplating printed circuit board using magnetic field having periodic directionality |
US20110042223A1 (en) * | 2009-08-24 | 2011-02-24 | Ezekiel Kruglick | Magnetic Electro-Plating |
CN102482791A (en) * | 2009-08-24 | 2012-05-30 | 英派尔科技开发有限公司 | Magnetic electro-plating |
US9797057B2 (en) * | 2009-08-24 | 2017-10-24 | Empire Technology Development Llc | Magnetic electro-plating |
CN103160903A (en) * | 2011-12-16 | 2013-06-19 | 深圳富泰宏精密工业有限公司 | Anodization coloring apparatus and treating method of coloring by using same |
CN103160903B (en) * | 2011-12-16 | 2017-02-22 | 富智康精密电子(廊坊)有限公司 | Anodization coloring apparatus and treating method of coloring by using same |
CN113493920A (en) * | 2020-03-19 | 2021-10-12 | 芯恩(青岛)集成电路有限公司 | Device and method for improving uniformity of electroplating film |
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Owner name: LSI LOGIC CORORATION, CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BERMAN, MICHAEL J.;REDER, STEVEN E.;REEL/FRAME:015366/0409 Effective date: 20040520 |
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Owner name: LSI CORPORATION, CALIFORNIA Free format text: MERGER;ASSIGNOR:LSI SUBSIDIARY CORP.;REEL/FRAME:020548/0977 Effective date: 20070404 Owner name: LSI CORPORATION,CALIFORNIA Free format text: MERGER;ASSIGNOR:LSI SUBSIDIARY CORP.;REEL/FRAME:020548/0977 Effective date: 20070404 |
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