Patents by Inventor Rajendra D. Pendse

Rajendra D. Pendse 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).

  • Publication number: 20140225257
    Abstract: A semiconductor device has a semiconductor die with die bump pads and substrate with trace lines having integrated bump pads. A solder mask patch is formed interstitially between the die bump pads or integrated bump pads. The solder mask patch contains non-wettable material. Conductive bump material is deposited over the integrated bump pads or die bump pads. The semiconductor die is mounted over the substrate so that the conductive bump material is disposed between the die bump pads and integrated bump pads. The bump material is reflowed without a solder mask around the integrated bump pads to form an interconnect between the semiconductor die and substrate. The solder mask patch confines the conductive bump material within a footprint of the die bump pads or integrated bump pads during reflow. The interconnect can have a non-fusible base and fusible cap.
    Type: Application
    Filed: April 22, 2014
    Publication date: August 14, 2014
    Applicant: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8759972
    Abstract: A semiconductor device has a semiconductor die mounted to a substrate with a plurality of composite interconnects formed between interconnect sites on the substrate and bump pads on the die. The interconnect sites are part of traces formed on the substrate. The interconnect site has a width between 1.0 and 1.2 times a width of the trace. The composite interconnect is tapered. The composite interconnects have a fusible portion connected to the interconnect site and non-fusible portion connected to the bump pad. The non-fusible portion can be gold, copper, nickel, lead solder, or lead-tin alloy. The fusible portion can be tin, lead-free alloy, tin-silver alloy, tin-silver-copper alloy, tin-silver-indium alloy, eutectic solder, or other tin alloys with silver, copper, or lead. An underfill material is deposited between the semiconductor die and substrate. A finish such as Cu-OSP can be formed over the substrate.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: June 24, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8741766
    Abstract: A semiconductor device has a semiconductor die with die bump pads and substrate with trace lines having integrated bump pads. A solder mask patch is formed interstitially between the die bump pads or integrated bump pads. The solder mask patch contains non-wettable material. Conductive bump material is deposited over the integrated bump pads or die bump pads. The semiconductor die is mounted over the substrate so that the conductive bump material is disposed between the die bump pads and integrated bump pads. The bump material is reflowed without a solder mask around the integrated bump pads to form an interconnect between the semiconductor die and substrate. The solder mask patch confines the conductive bump material within a footprint of the die bump pads or integrated bump pads during reflow. The interconnect can have a non-fusible base and fusible cap.
    Type: Grant
    Filed: May 30, 2013
    Date of Patent: June 3, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Publication number: 20140145340
    Abstract: A flip chip interconnection structure is formed by mechanically interlocking joining surfaces of a first and second element. The first element, which may be a bump on an integrated circuit chip, includes a soft, deformable material with a low yield strength and high elongation to failure. The surface of the second element, which may for example be a substrate pad, is provided with asperities into which the first element deforms plastically under pressure to form the mechanical interlock.
    Type: Application
    Filed: January 31, 2014
    Publication date: May 29, 2014
    Inventor: Rajendra D. Pendse
  • Publication number: 20140131869
    Abstract: A semiconductor device has a semiconductor die with a die bump pad and substrate with a trace line and integrated bump pad. Conductive bump material is deposited on the substrate bump pad or die bump pad. The semiconductor die is mounted over the substrate so that the bump material is disposed between the die bump pad and substrate bump pad. The bump material is reflowed without a solder mask around the die bump pad or substrate bump pad to form an interconnect. The bump material is self-confined within a footprint of the die bump pad or substrate bump pad. The bump material can be immersed in a flux solution prior to reflow to increase wettability. Alternatively, the interconnect includes a non-fusible base and fusible cap. The volume of bump material is selected so that a surface tension maintains self-confinement of the bump material within the bump pads during reflow.
    Type: Application
    Filed: January 22, 2014
    Publication date: May 15, 2014
    Applicant: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Publication number: 20140113446
    Abstract: A semiconductor device has a semiconductor die having a plurality of die bump pad and substrate having a plurality of conductive trace with an interconnect site. A solder mask patch is formed interstitially between the die bump pads or interconnect sites. A conductive bump material is deposited on the interconnect sites or die bump pads. The semiconductor die is mounted to the substrate so that the conductive bump material is disposed between the die bump pads and interconnect sites. The conductive bump material is reflowed without a solder mask around the die bump pad or interconnect site to form an interconnect structure between the semiconductor die and substrate. The solder mask patch confines the conductive bump material within the die bump pad or interconnect site. The interconnect structure can include a fusible portion and non-fusible portion. An encapsulant is deposited between the semiconductor die and substrate.
    Type: Application
    Filed: December 31, 2013
    Publication date: April 24, 2014
    Applicant: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8697490
    Abstract: A flip chip interconnection structure is formed by mechanically interlocking joining surfaces of a first and second element. The first element, which may be a bump on an integrated circuit chip, includes a soft, deformable material with a low yield strength and high elongation to failure. The surface of the second element, which may for example be a substrate pad, is provided with asperities into which the first element deforms plastically under pressure to form the mechanical interlock.
    Type: Grant
    Filed: July 1, 2011
    Date of Patent: April 15, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8674500
    Abstract: A semiconductor device has a semiconductor die with a die bump pad and substrate with a trace line and integrated bump pad. Conductive bump material is deposited on the substrate bump pad or die bump pad. The semiconductor die is mounted over the substrate so that the bump material is disposed between the die bump pad and substrate bump pad. The bump material is reflowed without a solder mask around the die bump pad or substrate bump pad to form an interconnect. The bump material is self-confined within a footprint of the die bump pad or substrate bump pad. The bump material can be immersed in a flux solution prior to reflow to increase wettability. Alternatively, the interconnect includes a non-fusible base and fusible cap. The volume of bump material is selected so that a surface tension maintains self-confinement of the bump material within the bump pads during reflow.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: March 18, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8659172
    Abstract: A semiconductor device has a semiconductor die having a plurality of die bump pad and substrate having a plurality of conductive trace with an interconnect site. A solder mask patch is formed interstitially between the die bump pads or interconnect sites. A conductive bump material is deposited on the interconnect sites or die bump pads. The semiconductor die is mounted to the substrate so that the conductive bump material is disposed between the die bump pads and interconnect sites. The conductive bump material is reflowed without a solder mask around the die bump pad or interconnect site to form an interconnect structure between the semiconductor die and substrate. The solder mask patch confines the conductive bump material within the die bump pad or interconnect site. The interconnect structure can include a fusible portion and non-fusible portion. An encapsulant is deposited between the semiconductor die and substrate.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: February 25, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Publication number: 20140008792
    Abstract: A semiconductor device has a semiconductor die with a plurality of composite bumps formed over a surface of the semiconductor die. The composite bumps have a fusible portion and non-fusible portion, such as a conductive pillar and bump formed over the conductive pillar. The composite bumps can also be tapered. Conductive traces are formed over a substrate with interconnect sites having edges parallel to the conductive trace from a plan view for increasing escape routing density. The interconnect site can have a width less than 1.2 times a width of the conductive trace. The composite bumps are wider than the interconnect sites. The fusible portion of the composite bumps is bonded to the interconnect sites so that the fusible portion covers a top surface and side surface of the interconnect sites. An encapsulant is deposited around the composite bumps between the semiconductor die and substrate.
    Type: Application
    Filed: September 9, 2013
    Publication date: January 9, 2014
    Applicant: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Publication number: 20130328189
    Abstract: A semiconductor device has a semiconductor die with a plurality of bumps formed over the die. A substrate has a plurality of conductive traces formed on the substrate. Each trace has an interconnect site for mating to the bumps. The interconnect sites have parallel edges along a length of the conductive traces under the bumps from a plan view for increasing escape routing density. The bumps have a noncollapsible portion for attaching to a contact pad on the die and fusible portion for attaching to the interconnect site. The fusible portion melts at a temperature which avoids damage to the substrate during reflow. The noncollapsible portion includes lead solder, and fusible portion includes eutectic solder. The interconnect sites have a width which is less than 1.2 times a width of the conductive trace. Alternatively, the interconnect sites have a width which is less than one-half a diameter of the bump.
    Type: Application
    Filed: August 13, 2013
    Publication date: December 12, 2013
    Applicant: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Publication number: 20130292829
    Abstract: A semiconductor package having an embedded die and solid vertical interconnections, such as stud bump interconnections, for increased integration in the direction of the z-axis (i.e., in a direction normal to the circuit side of the die). The semiconductor package can include a die mounted in a face-up configuration (similar to a wire bond package) or in a face-down or flip chip configuration.
    Type: Application
    Filed: July 3, 2013
    Publication date: November 7, 2013
    Inventor: Rajendra D. Pendse
  • Patent number: 8574959
    Abstract: A semiconductor device has a semiconductor die with a plurality of composite bumps formed over a surface of the semiconductor die. The composite bumps have a fusible portion and non-fusible portion, such as a conductive pillar and bump formed over the conductive pillar. The composite bumps can also be tapered. Conductive traces are formed over a substrate with interconnect sites having edges parallel to the conductive trace from a plan view for increasing escape routing density. The interconnect site can have a width less than 1.2 times a width of the conductive trace. The composite bumps are wider than the interconnect sites. The fusible portion of the composite bumps is bonded to the interconnect sites so that the fusible portion covers a top surface and side surface of the interconnect sites. An encapsulant is deposited around the composite bumps between the semiconductor die and substrate.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: November 5, 2013
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: 8575018
    Abstract: A semiconductor wafer has a first conductive layer formed over its active surface. A first insulating layer is formed over the substrate and first conductive layer. A second conductive layer is formed over the first conductive layer and first insulating layer. A UBM layer is formed around a bump formation area over the second conductive layer. The UBM layer can be two stacked metal layers or three stacked metal layers. The second conductive layer is exposed in the bump formation area. A second insulating layer is formed over the UBM layer and second conductive layer. A portion of the second insulating layer is removed over the bump formation area and a portion of the UBM layer. A bump is formed over the second conductive layer in the bump formation area. The bump contacts the UBM layer to seal a contact interface between the bump and second conductive layer.
    Type: Grant
    Filed: December 1, 2009
    Date of Patent: November 5, 2013
    Assignee: STATS ChipPAC, Ltd.
    Inventors: Yaojian Lin, Jianmin Fang, Kang Chen, Pandi Chelvam Marimuthu, Rajendra D. Pendse
  • Publication number: 20130277826
    Abstract: A semiconductor device has a semiconductor die with a plurality of composite bumps formed over a surface of the semiconductor die. The composite bumps have a fusible portion and non-fusible portion, such as a conductive pillar and bump formed over the conductive pillar. The composite bumps can also be tapered. Conductive traces are formed over a substrate with interconnect sites having edges parallel to the conductive trace from a plan view for increasing escape routing density. The interconnect site can have a width less than 1.2 times a width of the conductive trace. The composite bumps are wider than the interconnect sites. The fusible portion of the composite bumps is bonded to the interconnect sites so that the fusible portion covers a top surface and side surface of the interconnect sites. An encapsulant is deposited around the composite bumps between the semiconductor die and substrate.
    Type: Application
    Filed: December 3, 2010
    Publication date: October 24, 2013
    Applicant: STATS CHIPPAC, LTD.
    Inventor: Rajendra D. Pendse
  • Publication number: 20130277827
    Abstract: A semiconductor device has a semiconductor die mounted to a substrate with a plurality of composite interconnects formed between interconnect sites on the substrate and bump pads on the die. The interconnect sites are part of traces formed on the substrate. The interconnect site has a width between 1.0 and 1.2 times a width of the trace. The composite interconnect is tapered. The composite interconnects have a fusible portion connected to the interconnect site and non-fusible portion connected to the bump pad. The non-fusible portion can be gold, copper, nickel, lead solder, or lead-tin alloy. The fusible portion can be tin, lead-free alloy, tin-silver alloy, tin-silver-copper alloy, tin-silver-indium alloy, eutectic solder, or other tin alloys with silver, copper, or lead. An underfill material is deposited between the semiconductor die and substrate. A finish such as Cu—OSP can be formed over the substrate.
    Type: Application
    Filed: November 29, 2011
    Publication date: October 24, 2013
    Applicant: STATS CHIPPAC, LTD.
    Inventor: Rajendra D. Pendse
  • Patent number: RE44562
    Abstract: A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. A solder mask has an opening over the interconnect site, and the solder mask makes contact with the interconnect structure, or is in close proximity to the interconnect structure, at the margin of the opening. The flip chip interconnect is provided with an underfill. During the underfill process, the contact (or near proximity) of the solder mask with the interconnect structure interferes with flow of the underfill material toward the substrate adjacent the site, resulting in formation of a void left unfilled by the underfill, adjacent the contact of the interconnect structure with the site on the substrate metallization. The void can help provide relief from strain induced by changes in temperature of the system.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: October 29, 2013
    Assignee: STATS ChipPAC, Ltd.
    Inventors: Rajendra D. Pendse, KyungOe Kim, TaeWoo Kang
  • Patent number: RE44579
    Abstract: A semiconductor device has a semiconductor die with an die bump pad and substrate with a trace line and integrated bump pad. Conductive bump material is deposited on the substrate bump pad or die bump pad. The semiconductor die over the substrate so that the bump material is disposed between the die bump pad and substrate bump pad. The bump material is reflowed without a solder mask around the die bump pad or substrate bump pad to form an interconnect. The bump material is self-confined within a footprint of the die bump pad or substrate bump pad. The bump material can be immersed in a flux solution prior to reflow to increase wettability. Alternatively, the interconnect includes a non-fusible base and fusible cap. The volume of bump material is selected so that a surface tension maintains self-confinement of the bump material within the bump pads during reflow.
    Type: Grant
    Filed: February 1, 2013
    Date of Patent: November 5, 2013
    Assignee: STATS ChipPAC, Ltd.
    Inventor: Rajendra D. Pendse
  • Patent number: RE44608
    Abstract: A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. Also, a bond-on-lead or bond-on-narrow pad or bond on a small area of a contact pad interconnection includes such tapering flip chip interconnects. Also, methods for making the interconnect structure include providing a die having interconnect pads, providing a substrate having interconnect sites on a patterned conductive layer, providing a bump on a die pad, providing a fusible electrically conductive material either at the interconnect site or on the bump, mating the bump to the interconnect site, and heating to melt the fusible material.
    Type: Grant
    Filed: February 1, 2013
    Date of Patent: November 26, 2013
    Assignee: STATS ChipPAC, Ltd.
    Inventors: Rajendra D. Pendse, KyungOe Kim, TaeWoo Kang
  • Patent number: RE44761
    Abstract: A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. A solder mask has an opening over the interconnect site, and the solder mask makes contact with the interconnect structure, or is in close proximity to the interconnect structure, at the margin of the opening. The flip chip interconnect is provided with an underfill. During the underfill process, the contact (or near proximity) of the solder mask with the interconnect structure interferes with flow of the underfill material toward the substrate adjacent the site, resulting in formation of a void left unfilled by the underfill, adjacent the contact of the interconnect structure with the site on the substrate metallization. The void can help provide relief from strain induced by changes in temperature of the system.
    Type: Grant
    Filed: February 1, 2013
    Date of Patent: February 11, 2014
    Assignee: STATS ChipPAC, Ltd.
    Inventors: Rajendra D. Pendse, KyungOe Kim, TaeWoo Kang