Patents by Inventor Srivatsa Kundalgurki

Srivatsa Kundalgurki 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).

  • Patent number: 7863149
    Abstract: In a method for fabricating a capacitor that includes an electrode structure (80), an auxiliary layer (40) is formed over a substrate (10). A recess (60), which determines the shape of the electrode structure (80), is etched into the auxiliary layer (40), and the electrode structure of the capacitor is formed in the recess. As an example, the auxiliary layer can be a semiconductor layer (40).
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: January 4, 2011
    Assignee: Qimonda AG
    Inventors: Srivatsa Kundalgurki, Peter Moll, Dirk Manger, Kristin Schupke, Till Schloesser
  • Patent number: 7579253
    Abstract: Bottom electrodes of stacked capacitor DRAM cells are formed by depositing a metal layer on the side walls of trenches within a hard mask layer, which serves as a mold for the bottom electrode elements. Prior to depositing the hard mask layer a sacrificial first metal layer is disposed, which results in an electrically conductive surface on the semiconductor wafer. The mask layer is wet-etched to release the bottom electrode as free standing elements on the semiconductor surface. Using the conductive path provided by the first and the second metal layers, the bottom electrodes are polarized in a cleaning liquid bath during a wafer drying process. The generated repulsive electric field overcomes the attractive forces between the neighboring bottom electrode elements induced due to capillary effects of the liquids used for etching and cleaning.
    Type: Grant
    Filed: April 9, 2007
    Date of Patent: August 25, 2009
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7319223
    Abstract: Method and apparatus for characterizing a recess located on a surface of a substrate are provided. One embodiment of the invention provides a method for characterizing a recess located on a surface of a substrate. In a first step, a measurement tip is positioned directly above the recess. Subsequently, an electrically conductive path is provided between the measurement tip and the bottom of the recess by ionizing a medium located in the recess. A voltage is applied between the measurement tip and the substrate to measure a current flowing between the measurement tip and the bottom of the recess. The recess is characterized on the basis of the magnitude of the measured current. Another embodiment of the invention provides an apparatus for performing the method for characterizing a recess.
    Type: Grant
    Filed: September 14, 2004
    Date of Patent: January 15, 2008
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7284558
    Abstract: The present invention relates to the use of a C1 to C5 alcohol during the cleaning step. With the use of said alcohol, the surface tension of the solution is reduced which allows the application of reduced megasonic power with increased cleaning efficiency.
    Type: Grant
    Filed: February 15, 2005
    Date of Patent: October 23, 2007
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7259061
    Abstract: Integrated circuits can include an integrated capacitor with a metal alloy layer. Methods for forming such integrated circuits can include providing a substrate, forming a first electrode including depositing a metal alloy layer having a first surface and an exposed second surface, etching the exposed second surface of the metal alloy layer thereby increasing the surface roughness of the second surface of the metal alloy layer, forming a capacitor dielectric on the first electrode and forming a second electrode on the capacitor dielectric. By providing a metal alloy layer and etching the second surface of the metal alloy layer, an increased capacitance of the integrated capacitor is achieved.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: August 21, 2007
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20070184659
    Abstract: Bottom electrodes of stacked capacitor DRAM cells are formed by depositing a metal layer on the side walls of trenches within a hard mask layer, which serves as a mold for the bottom electrode elements. Prior to depositing the hard mask layer a sacrificial first metal layer is disposed, which results in an electrically conductive surface on the semiconductor wafer. The mask layer is wet-etched to release the bottom electrode as free standing elements on the semiconductor surface. Using the conductive path provided by the first and the second metal layers, the bottom electrodes are polarized in a cleaning liquid bath during a wafer drying process. The generated repulsive electric field overcomes the attractive forces between the neighboring bottom electrode elements induced due to capillary effects of the liquids used for etching and cleaning.
    Type: Application
    Filed: April 9, 2007
    Publication date: August 9, 2007
    Applicant: INFINEON TECHNOLOGIES AG
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7208095
    Abstract: Bottom electrodes of stacked capacitor DRAM cells are formed by depositing a metal layer on the side walls of trenches within a hard mask layer, which serves as a mold for the bottom electrode elements. Prior to depositing the hard mask layer a sacrificial first metal layer is disposed, which leads to a electrical conductive surface on the semiconductor wafer. The mask layer is wet-etched to release the bottom electrode as free standing elements on the semiconductor surface. Using the conductive path provided by the first and the second metal layer, the bottom electrodes are polarized in a cleaning liquid bath during a wafer drying process. The generated repulsive electric field overcomes the attractive forces between the neighboring bottom electrode elements induced due to capillary effects of the liquids used for etching and cleaning.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: April 24, 2007
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20060180172
    Abstract: The present invention relates to the use of a C1 to C5 alcohol during the cleaning step. With the use of said alcohol, the surface tension of the solution is reduced which allows the application of reduced megasonic power with increased cleaning efficiency.
    Type: Application
    Filed: February 15, 2005
    Publication date: August 17, 2006
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7084029
    Abstract: To fabricate a hole trench storage capacitor having an inner electrode, which is formed in a hole trench, and an outer electrode, which is formed in an electrode section, surrounding the hole trench in a lower section, of the semiconductor substrate, the inner electrode is continued above the substrate surface of the semiconductor substrate. Then, an additional layer, which widens the semiconductor substrate, is grown onto the substrate surface by an epitaxy process. A transition surface for contact-connection of the inner electrode and at least a part of an insulation collar is formed above the original substrate surface, thereby increasing the size of a surface area of the hole trench storage capacitor, which can be used for charge storage, while using the same aspect ratio for an etch used to form the hole trench.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: August 1, 2006
    Assignee: Infineon Technologies, AG
    Inventors: Srivatsa Kundalgurki, Dietmar Temmler, Hans-Peter Moll, Joerg Wiedemann
  • Publication number: 20060124582
    Abstract: Bottom electrodes of stacked capacitor DRAM cells are formed by depositing a metal layer on the side walls of trenches within a hard mask layer, which serves as a mold for the bottom electrode elements. Prior to depositing the hard mask layer a sacrificial first metal layer is disposed, which leads to a electrical conductive surface on the semiconductor wafer. The mask layer is wet-etched to release the bottom electrode as free standing elements on the semiconductor surface. Using the conductive path provided by the first and the second metal layer, the bottom electrodes are polarized in a cleaning liquid bath during a wafer drying process. The generated repulsive electric field overcomes the attractive forces between the neighboring bottom electrode elements induced due to capillary effects of the liquids used for etching and cleaning.
    Type: Application
    Filed: December 15, 2004
    Publication date: June 15, 2006
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20060079049
    Abstract: In a method for fabricating a capacitor that includes an electrode structure (80), an auxiliary layer (40) is formed over a substrate (10). A recess (60), which determines the shape of the electrode structure (80), is etched into the auxiliary layer (40), and the electrode structure of the capacitor is formed in the recess. As an example, the auxiliary layer can be a semiconductor layer (40).
    Type: Application
    Filed: September 9, 2005
    Publication date: April 13, 2006
    Inventors: Srivatsa Kundalgurki, Peter Moll, Dirk Manger, Kristin Schupke, Till Schloesser
  • Patent number: 7018893
    Abstract: Bottom electrodes of stacked capacitor cells are formed by lining a patterned hard mask with a conductive layer. The hard mask is formed by a layered stack. Subsequent to the formation of trenches within the hard mask, the top-most masking layer of the layer stack is laterally recessed. The bottom electrode layer is then deposited to line the trenches. Following this, the bottom electrode layer is removed from the top of the hardmask. Subsequently, the hard mask is removed. As a result, released and free-standing elements of the conductive layer are formed as bottom electrodes that include a hydrophobic contact area in the top part of the bottom electrodes.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: March 28, 2006
    Assignee: Infineon Technologies, AG
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20060054812
    Abstract: Method and apparatus for characterizing a recess located on a surface of a substrate are provided. One embodiment of the invention provides a method for characterizing a recess located on a surface of a substrate. In a first step, a measurement tip is positioned directly above the recess. Subsequently, an electrically conductive path is provided between the measurement tip and the bottom of the recess by ionizing a medium located in the recess. A voltage is applied between the measurement tip and the substrate to measure a current flowing between the measurement tip and the bottom of the recess. The recess is characterized on the basis of the magnitude of the measured current. Another embodiment of the invention provides an apparatus for performing the method for characterizing a recess.
    Type: Application
    Filed: September 14, 2004
    Publication date: March 16, 2006
    Inventor: Srivatsa Kundalgurki
  • Patent number: 7005385
    Abstract: The present invention relates to a method for removing a resist selective to a carbon hard mask including providing an etching plasma comprising of at least hydrogen at a predetermined temperature level and a predetermined pressure level in a reaction chamber, and etching the resist selectively to the mask with said plasma for a predetermined period of time.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: February 28, 2006
    Assignee: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20060032516
    Abstract: A process for removing residue from one or more surfaces of chamber components exposed to the interior of a semiconductor process chamber. A plasma chamber is supplied with a gas mixture including nitrogen (N2) and hydrogen (H2), the nitrogen and hydrogen being included in volume % from 2 to 10 of hydrogen and from 98 to 90 of nitrogen, thereby forming a plasma in the plasma chamber so as to decompose a portion of the nitrogen (N2) and hydrogen (H2) to atomic N and/or H. The interior of the semiconductor process chamber is thus exposed to at least a portion of the atomic N and/or H.
    Type: Application
    Filed: July 30, 2004
    Publication date: February 16, 2006
    Applicants: Infineon Technologies AG, Novellus Systems, Inc.
    Inventors: Srivatsa Kundalgurki, Haruhiro Goto, David Chen
  • Publication number: 20060014343
    Abstract: Integrated circuits can include an integrated capacitor with a metal alloy layer. Methods for forming such integrated circuits can include providing a substrate, forming a first electrode including depositing a metal alloy layer having a first surface and an exposed second surface, etching the exposed second surface of the metal alloy layer thereby increasing the surface roughness of the second surface of the metal alloy layer, forming a capacitor dielectric on the first electrode and forming a second electrode on the capacitor dielectric. By providing a metal alloy layer and etching the second surface of the metal alloy layer, an increased capacitance of the integrated capacitor is achieved.
    Type: Application
    Filed: July 15, 2004
    Publication date: January 19, 2006
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20050130421
    Abstract: The present invention relates to a method for removing a resist selective to a carbon hard mask including providing an etching plasma comprising of at least hydrogen at a predetermined temperature level and a predetermined pressure level in a reaction chamber, and etching the resist selectively to the mask with said plasma for a predetermined period of time.
    Type: Application
    Filed: December 15, 2003
    Publication date: June 16, 2005
    Applicant: Infineon Technologies AG
    Inventor: Srivatsa Kundalgurki
  • Publication number: 20050093049
    Abstract: To fabricate a hole trench storage capacitor having an inner electrode, which is formed in a hole trench, and an outer electrode, which is formed in an electrode section, surrounding the hole trench in a lower section, of the semiconductor substrate, the inner electrode is continued above the substrate surface of the semiconductor substrate. Then, an additional layer, which widens the semiconductor substrate, is grown onto the substrate surface by an epitaxy process. A transition surface for contact-connection of the inner electrode and at least a part of an insulation collar is formed above the original substrate surface, thereby increasing the size of a surface area of the hole trench storage capacitor, which can be used for charge storage, while using the same aspect ratio for an etch used to form the hole trench.
    Type: Application
    Filed: September 24, 2004
    Publication date: May 5, 2005
    Inventors: Srivatsa Kundalgurki, Dietmar Temmler, Hans-Peter Moll, Joerg Wiedemann