Patents by Inventor Shengwu Chang
Shengwu Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20190259560Abstract: Provided herein are approaches for reducing particles in an ion implanter. An electrostatic filter may include a housing and a plurality of conductive beam optics within the housing. The conductive beam optics are arranged around an ion beam-line directed towards a wafer, and may include entrance aperture electrodes proximate an entrance aperture of the housing. The conductive beam optics may further include energetic electrodes downstream along the ion beam-line from the entrance aperture electrodes, and ground electrodes downstream from the energetic electrodes. The energetic electrodes are positioned farther away from the ion beam-line than the entrance electrodes and the ground electrodes, thus causing the energetic electrodes to be physically blocked from impact by an envelope of back-sputter material returning from the wafer. The electrostatic filter may further include an electrical system for independently delivering a voltage and a current to each of the conductive beam optics.Type: ApplicationFiled: February 21, 2018Publication date: August 22, 2019Applicant: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Frank Sinclair, Alexandre Likhanskii, Christopher Campbell, Robert C. Lindberg, Eric D. Hermanson
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Publication number: 20190198283Abstract: An apparatus may include an electrode assembly, the electrode assembly comprising a plurality of electrodes, arranged in a plurality of electrode pairs arranged to conduct an ion beam therethrough. A given electrode pair lies along a radius of an arc describing a nominal central ray trajectory, wherein a radius of a first electrode pair and an adjacent electrode pair define an angular spacing. The plurality of electrode pairs may define a plurality of angular spacings, wherein, in a first configuration, the plurality of angular spacings are not all equal. The apparatus may also include a power supply in communication with the EM, the power supply configured to independently supply voltage to the plurality of electrodes.Type: ApplicationFiled: April 9, 2018Publication date: June 27, 2019Applicant: Varian Semiconductor Equipment Associates, Inc.Inventors: Svetlana Radovanov, Ana Samolov, Shengwu Chang, Frank Sinclair, Peter L. Kellerman
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Patent number: 10074514Abstract: An apparatus may include an electrode system, the electrode system comprising a plurality of electrodes to guide an ion beam from an entrance aperture to an exit aperture, and a voltage supply to apply a plurality of voltages to the electrode system. The electrode system may comprise an exit electrode assembly, where the exit electrode assembly includes a first exit electrode and a second exit electrode, separated from the first exit electrode by an electrode gap. The first exit electrode and the second exit electrode may be movable with respect to one another so as to change a size of the electrode gap over a gap range.Type: GrantFiled: September 8, 2017Date of Patent: September 11, 2018Assignee: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.Inventors: Shengwu Chang, Frank Sinclair, Alexandre Likhanskii, Philip Layne
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Patent number: 9934928Abstract: Provided herein are approaches for improving ion beam extraction stability and ion beam current for an ion extraction system. In one approach, a source housing assembly may include a source housing surrounding an ion source including an arc chamber, the source housing having an extraction aperture plate mounted at a proximal end thereof. The source housing assembly further includes a vacuum liner disposed within an interior of the source housing to form a barrier around a set of vacuum pumping apertures. As configured, openings in the source housing assembly, other than an opening in the extraction aperture plate, are enclosed by the extraction aperture plate and the vacuum liner, thus ensuring appendix arcs or extraneous ions produced outside the arc chamber remain within the source housing. Just those ions produced within the arc chamber exit the source housing through the opening of the extraction aperture plate.Type: GrantFiled: May 15, 2015Date of Patent: April 3, 2018Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Jeff Burgess, William Leavitt, Michael St Peter, Matt Mosher, Joe Olson, Frank Sinclair
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Patent number: 9679745Abstract: Provided herein are approaches for controlling an ion beam within an accelerator/decelerator. In an exemplary approach, an ion implantation system includes an ion source for generating an ion beam, and a terminal suppression electrode coupled to a terminal, wherein the terminal suppression electrode is configured to conduct the ion beam through an aperture of the terminal suppression electrode and to apply a first potential to the ion beam from a first voltage supply. The system further includes a lens coupled to the terminal and disposed adjacent the terminal suppression electrode, wherein the lens is configured to conduct the ion beam through an aperture of the lens and to apply a second potential to the ion beam from a second voltage supply. In an exemplary approach, the lens is electrically insulated from the terminal suppression electrode and independently driven, thus allowing for an increased beam current operation range.Type: GrantFiled: October 14, 2015Date of Patent: June 13, 2017Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Kristen Rounds, William Leavitt, Daniel Brosnan
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Publication number: 20170110286Abstract: Provided herein are approaches for controlling an ion beam within an accelerator/decelerator. In an exemplary approach, an ion implantation system includes an ion source for generating an ion beam, and a terminal suppression electrode coupled to a terminal, wherein the terminal suppression electrode is configured to conduct the ion beam through an aperture of the terminal suppression electrode and to apply a first potential to the ion beam from a first voltage supply. The system further includes a lens coupled to the terminal and disposed adjacent the terminal suppression electrode, wherein the lens is configured to conduct the ion beam through an aperture of the lens and to apply a second potential to the ion beam from a second voltage supply. In an exemplary approach, the lens is electrically insulated from the terminal suppression electrode and independently driven, thus allowing for an increased beam current operation range.Type: ApplicationFiled: October 14, 2015Publication date: April 20, 2017Inventors: Shengwu Chang, Kristen Rounds, William Leavitt, Daniel Brosnan
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Patent number: 9520204Abstract: A cold stripper for a high-energy ion implanter system is provided. The cold stripper including a stripper tube having a hollow cavity, a first aperture in the stripper tube to admit an ion beam of positively charged ions into the hollow cavity and a second aperture in the stripper tube to discharge the ion beam from the hollow cavity, a gas pump coupled to the hollow cavity to introduce a gas into the hollow cavity, one or more cooling passages in the stripper tube, and a coolant pump coupled to the one or more cooling passages to circulate a coolant through the one or more cooling passages.Type: GrantFiled: December 26, 2013Date of Patent: December 13, 2016Assignee: Varian Semiconductor Equipment Associates, Inc.Inventor: Shengwu Chang
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Publication number: 20160336138Abstract: Provided herein are approaches for improving ion beam extraction stability and ion beam current for an ion extraction system. In one approach, a source housing assembly may include a source housing surrounding an ion source including an arc chamber, the source housing having an extraction aperture plate mounted at a proximal end thereof. The source housing assembly further includes a vacuum liner disposed within an interior of the source housing to form a barrier around a set of vacuum pumping apertures. As configured, openings in the source housing assembly, other than an opening in the extraction aperture plate, are enclosed by the extraction aperture plate and the vacuum liner, thus ensuring appendix arcs or extraneous ions produced outside the arc chamber remain within the source housing. Just those ions produced within the arc chamber exit the source housing through the opening of the extraction aperture plate.Type: ApplicationFiled: May 15, 2015Publication date: November 17, 2016Inventors: Shengwu Chang, Jeff Burgess, William Leavitt, Michael St Peter, Matt Mosher, Joe Olson, Frank Sinclair
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Patent number: 9437341Abstract: An apparatus to generate negative hydrogen ions includes an ion source operative to generate positive hydrogen ions, a first component to adjust positive molecular hydrogen ion species in the ion source, a second component to adjust extraction voltage for extraction of the positive molecular hydrogen ions from the ion source, and a charge exchange cell comprising charge exchange species to convert the extracted positive molecular hydrogen ions to negative hydrogen ions. The adjusted extraction voltage is effective to generate an ion energy to maximize negative ion current yield in the charge exchange cell based upon a product of extraction efficiency of the positive molecular hydrogen ions and a peak in charge exchange efficiency for converting a species of the positive molecular hydrogen ions to negative hydrogen ions through charge exchange between the extracted hydrogen ions and charge exchange species.Type: GrantFiled: March 13, 2013Date of Patent: September 6, 2016Assignee: Varian Semiconductor Equipment Associates, Inc.Inventor: Shengwu Chang
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Publication number: 20160233048Abstract: An apparatus to control an ion beam for treating a substrate. The apparatus may include a fixed electrode configured to conduct the ion beam through a fixed electrode aperture and to apply a fixed electrode potential to the ion beam, a ground electrode assembly disposed downstream of the fixed electrode. The ground electrode assembly may include a base and a ground electrode disposed adjacent the fixed electrode and configured to conduct the ion beam through a ground electrode aperture, the ground electrode being reversibly movable along a first axis with respect to the fixed electrode between a first position and a second position, wherein a beam current of the ion beam at the substrate varies when the ground electrode moves between the first position and second position.Type: ApplicationFiled: February 6, 2015Publication date: August 11, 2016Inventors: Shengwu Chang, Kristen S. Rounds, William Leavitt, Michael St. Peter
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Patent number: 9396903Abstract: An apparatus to control an ion beam for treating a substrate. The apparatus may include a fixed electrode configured to conduct the ion beam through a fixed electrode aperture and to apply a fixed electrode potential to the ion beam, a ground electrode assembly disposed downstream of the fixed electrode. The ground electrode assembly may include a base and a ground electrode disposed adjacent the fixed electrode and configured to conduct the ion beam through a ground electrode aperture, the ground electrode being reversibly movable along a first axis with respect to the fixed electrode between a first position and a second position, wherein a beam current of the ion beam at the substrate varies when the ground electrode moves between the first position and second position.Type: GrantFiled: February 6, 2015Date of Patent: July 19, 2016Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Kristen S. Rounds, William Leavitt, Michael St. Peter
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Patent number: 9281165Abstract: A tandem accelerator and ion implanter with improved performance is disclosed. The tandem accelerator includes a plurality of input electrodes, a plurality of output electrodes and a high voltage terminal disposed therebetween. The high voltage terminal includes a stripper tube. Neutral molecules are injected into the stripper tube, which remove electrons from the incoming negative ion beam. The resulting positive ions are accelerated toward the plurality of output electrodes. To reduce the amount of undesired positive ions that exit the stripper tube, bias electrodes is disposed at the entrance and exit of the stripper tube. The bias electrodes are biased a second voltage, greater than the first voltage applied to the terminal. The bias electrodes repel slow moving positive ions, preventing them from exiting the stripper tube and contaminating the workpiece.Type: GrantFiled: August 26, 2014Date of Patent: March 8, 2016Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Christopher Lupoli, William Davis Lee, Frank Sinclair, James Pixley
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Publication number: 20160064186Abstract: A tandem accelerator and ion implanter with improved performance is disclosed. The tandem accelerator includes a plurality of input electrodes, a plurality of output electrodes and a high voltage terminal disposed therebetween. The high voltage terminal includes a stripper tube. Neutral molecules are injected into the stripper tube, which remove electrons from the incoming negative ion beam. The resulting positive ions are accelerated toward the plurality of output electrodes. To reduce the amount of undesired positive ions that exit the stripper tube, bias electrodes is disposed at the entrance and exit of the stripper tube. The bias electrodes are biased a second voltage, greater than the first voltage applied to the terminal. The bias electrodes repel slow moving positive ions, preventing them from exiting the stripper tube and contaminating the workpiece.Type: ApplicationFiled: August 26, 2014Publication date: March 3, 2016Inventors: Shengwu Chang, Christopher Lupoli, William Davis Lee, Frank Sinclair, James Pixley
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Patent number: 9263231Abstract: An ion implant apparatus and moveable ion beam current sensor are described. Various examples provide moving the ion beam current sensor during an ion implant process such that a distance between the ion beam current sensor and a substrate is maintained during scanning of the ion beam toward the substrate. The ion beam current sensor is disposed on a moveable support configured to move the ion beam current sensor in a first direction corresponding to the scanning of the ion beam while the substrate is moved in a second direction.Type: GrantFiled: October 10, 2013Date of Patent: February 16, 2016Assignee: Varian Semiconductor Equipment Associates, Inc.Inventor: Shengwu Chang
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Patent number: 9165744Abstract: An ion beam scanning assembly includes a set of scanning electrodes defining a gap to accept an ion beam and scan the ion beam in a first plane, and a multipole electrostatic lens system comprising a plurality of electrodes arranged along a portion of a path of travel of the ion beam bounded by the pair of scanning electrodes, the multipole electrostatic lens system configured to shape the ion beam in a direction perpendicular to the first plane.Type: GrantFiled: October 24, 2012Date of Patent: October 20, 2015Assignee: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.Inventor: Shengwu Chang
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Publication number: 20150228445Abstract: A scan system for processing a substrate with an ion beam may include a scanner to receive the ion beam having a shape of a ribbon beam, the ribbon beam having a beam width along a first axis and beam height along a second axis that is perpendicular to the first axis, the beam width being at least three times greater than the beam height; and a scan power supply to send signals to the scanner to generate a deflecting field that deflects the ribbon beam along the second axis.Type: ApplicationFiled: February 13, 2014Publication date: August 13, 2015Applicant: Varian Semiconductor Equipment Associates, Inc.Inventor: Shengwu Chang
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Publication number: 20150187450Abstract: A cold stripper for a high-energy ion implanter system is provided. The cold stripper including a stripper tube having a hollow cavity, a first aperture in the stripper tube to admit an ion beam of positively charged ions into the hollow cavity and a second aperture in the stripper tube to discharge the ion beam from the hollow cavity, a gas pump coupled to the hollow cavity to introduce a gas into the hollow cavity, one or more cooling passages in the stripper tube, and a coolant pump coupled to the one or more cooling passages to circulate a coolant through the one or more cooling passages.Type: ApplicationFiled: December 26, 2013Publication date: July 2, 2015Applicant: Varian Semiconductor Equipment Associates, Inc.Inventor: Shengwu Chang
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Patent number: 9012337Abstract: A system and method for maintain a desired degree of platen flatness is disclosed. A laser system is used to measure the flatness of a platen. The temperature of the platen is then varied to achieve the desired level of flatness. In some embodiments, this laser system is only used during a set up period and the resulting desired temperature is then used during normal operation. In other embodiments, a laser system is used to measure the flatness of the platen, even while the workpiece is being processed.Type: GrantFiled: October 11, 2011Date of Patent: April 21, 2015Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Shengwu Chang, Joseph C. Olson, Frank Sinclair, Matthew P. McClellan, Antonella Cucchetti
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Publication number: 20150104885Abstract: An ion implant apparatus and moveable ion beam current sensor are described. Various examples provide moving the ion beam current sensor during an ion implant process such that a distance between the ion beam current sensor and a substrate is maintained during scanning of the ion beam toward the substrate. The ion beam current sensor is disposed on a moveable support configured to move the ion beam current sensor in a first direction corresponding to the scanning of the ion beam while the substrate is moved in a second direction.Type: ApplicationFiled: October 10, 2013Publication date: April 16, 2015Applicant: Varian Semiconductor Equipment Associates, Inc.Inventor: SHENGWU CHANG
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Patent number: 9006692Abstract: A system to control an ion beam in an ion implanter includes a detector to perform a plurality of beam current measurements of the ion beam along a first direction perpendicular to a direction of propagation of the ion beam. The system also includes an analysis component to determine a beam current profile based upon the plurality of beam current measurements, the beam current profile comprising a variation of beam current along the first direction; and an adjustment component to adjust a height of the ion beam along the first direction when the beam current profile indicates the beam height is below a threshold.Type: GrantFiled: September 25, 2013Date of Patent: April 14, 2015Assignee: Varian Semiconductor Equipment Associates, Inc.Inventors: Stanislav S. Todorov, George M. Gammel, Richard Allen Sprenkle, Norman E. Hussey, Frank Sinclair, Shengwu Chang, Joseph C. Olson, David Roger Timberlake, Kurt T. Decker-Lucke