Patents by Inventor Herbert L. Ho

Herbert L. Ho 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: 8198169
    Abstract: A deep trench is formed to a depth midway into a buried insulator layer of a semiconductor-on-insulator (SOI) substrate. A top semiconductor layer is laterally recessed by an isotropic etch that is selective to the buried insulator layer. The deep trench is then etched below a bottom surface of the buried insulator layer. Ion implantation is performed at an angle into the deep trench to dope the sidewalls of the deep trench beneath the buried insulator layer, while the laterally recessed sidewalls of the top semiconductor layer are not implanted with dopant ions. A node dielectric and trench fill materials are deposited into the deep trench. A buried strap has an upper buried strap sidewall that is offset from a lower buried strap sidewall and a deep trench sidewall.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: June 12, 2012
    Assignee: International Business Machines Corporation
    Inventors: MaryJane Brodsky, Kangguo Cheng, Herbert L. Ho, Paul C. Parries, Kevin R. Winstel
  • Patent number: 8193067
    Abstract: Disclosed is an integrated circuit having at least one deep trench isolation structure and a deep trench capacitor. A method of forming the integrated circuit incorporates a single etch process to simultaneously form first trench(s) and a second trenches for the deep trench isolation structure(s) and a deep trench capacitor, respectively. Following formation of a buried capacitor plate adjacent to the lower portion of the second trench, the trenches are lined with a conformal insulator layer and filled with a conductive material. Thus, for the deep trench capacitor, the conformal insulator layer functions as the capacitor dielectric and the conductive material as a capacitor plate in addition to the buried capacitor plate. A shallow trench isolation (STI) structure formed in the substrate extending across the top of the first trench(es) encapsulates the conductive material therein, thereby creating the deep trench isolation structure(s).
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: June 5, 2012
    Assignee: International Business Machines Corporation
    Inventors: Brent A. Anderson, Andres Bryant, Herbert L. Ho, Edward J. Nowak
  • Patent number: 8188528
    Abstract: A memory device is provided that in one embodiment includes a trench capacitor located in a semiconductor substrate including an outer electrode provided by the semiconductor substrate, an inner electrode provided by a conductive fill material, and a node dielectric layer located between the outer electrode and the inner electrode; and a semiconductor device positioned centrally over the trench capacitor. The semiconductor device includes a source region, a drain region, and a gate structure, in which the semiconductor device is formed on a semiconductor layer that is separated from the semiconductor substrate by a dielectric layer. A first contact is present extending from an upper surface of the semiconductor layer into electrical contact with the semiconductor substrate, and a second contact from the drain region of the semiconductor device in electrical contact to the conductive material within the at least one trench.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: May 29, 2012
    Assignee: International Buiness Machines Corporation
    Inventors: Chengwen Pei, Kangguo Cheng, Herbert L. Ho, Subramanian S. Iyer, Byeong Y. Kim, Geng Wang, Huilong Zhu
  • Publication number: 20120108050
    Abstract: Embedded DRAM MOSFETs including an array NFET having a gate stack comprising a high-K dielectric layer upon which is deposited a first metal oxide layer (CD1) then a conductive layer (TiN), and then a polysilicon layer (Poly). A logic PFET having substantially the same gate stack as the array NFET, and a logic NFET having a third gate stack comprising the high-K dielectric layer upon which is deposited the conductive layer (TiN) and then the polysilicon layer (Poly), without the first metal oxide layer (CD1) between the high-K dielectric layer and the conductive layer (TiN). The array NFET may therefore have a higher gate stack work function than the logic NFET, but substantially the same gate stack work function as the logic PFET.
    Type: Application
    Filed: January 5, 2012
    Publication date: May 3, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Xiangdong Chen, Herbert L. Ho, Geng Wang
  • Patent number: 8168507
    Abstract: A method for forming a memory device in a semiconductor on insulator substrate is provided, in which a protective oxide that is present on the sidewalls of the trench protects the first semiconductor layer, i.e., SOI layer, of the semiconductor on insulator substrate during bottle etching of the trench. In one embodiment, the protective oxide reduces back channel effects of the transistors to the memory devices in the trench that are formed in the semiconductor on insulator substrate. In another embodiment, a thermal oxidation process increases the thickness of the buried dielectric layer of a bonded semiconductor on insulator substrate by oxidizing the bonded interface between the buried dielectric layer and at least one semiconductor layers of the semiconductor on insulator substrate. The increased thickness of the buried dielectric layer may reduce back channel effects in devices formed on the substrate having trench memory structures.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: May 1, 2012
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Naoyoshi Kusaba, Karen A. Nummy, Carl J. Radens, Ravi M. Todi, Geng Wang
  • Publication number: 20120083092
    Abstract: A method for forming a memory device in a semiconductor on insulator substrate is provided, in which a protective oxide that is present on the sidewalls of the trench protects the first semiconductor layer, i.e., SOI layer, of the semiconductor on insulator substrate during bottle etching of the trench. In one embodiment, the protective oxide reduces back channel effects of the transistors to the memory devices in the trench that are formed in the semiconductor on insulator substrate. In another embodiment, a thermal oxidation process increases the thickness of the buried dielectric layer of a bonded semiconductor on insulator substrate by oxidizing the bonded interface between the buried dielectric layer and at least one semiconductor layers of the semiconductor on insulator substrate. The increased thickness of the buried dielectric layer may reduce back channel effects in devices formed on the substrate having trench memory structures.
    Type: Application
    Filed: December 12, 2011
    Publication date: April 5, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Herbert L. Ho, Naoyoshi Kusaba, Karen A. Nummy, Carl J. Radens, Ravi M. Todi, Geng Wang
  • Patent number: 8129797
    Abstract: Embedded DRAM MOSFETs including an array NFET having a gate stack comprising a high-K dielectric layer upon which is deposited a first metal oxide layer (CD1) then a conductive layer (TiN), and then a polysilicon layer (Poly). A logic PFET having substantially the same gate stack as the array NFET, and a logic NFET having a third gate stack comprising the high-K dielectric layer upon which is deposited the conductive layer (TiN) and then the polysilicon layer (Poly), without the first metal oxide layer (CD1) between the high-K dielectric layer and the conductive layer (TiN). The array NFET may therefore have a higher gate stack work function than the logic NFET, but substantially the same gate stack work function as the logic PFET.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: March 6, 2012
    Assignee: International Business Machines Corporation
    Inventors: Xiangdong Chen, Herbert L. Ho, Geng Wang
  • Patent number: 8120095
    Abstract: The present invention provides two-transistor silicon-oxide-nitride-oxide-semiconductor (2-Tr SONOS) non-volatile memory cells with randomly accessible storage locations as well as a design structure including the semiconductor memory devices embodied in a machine readable medium. In one embodiment, a 2-Tr SONOS cell is provided in which the select transistor is located with a trench structure having trench depth from 1 to 2 ?m and the memory transistor is located on a surface of a semiconductor substrate adjoining the trench structure. In another embodiment, a 2-Tr SONOS memory cell is provided in which both the select transistor and the memory transistor are located within a trench structure having the depth mentioned above.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: February 21, 2012
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Jack A. Mandelman, Tak H. Ning, Yoichi Otani
  • Patent number: 8110464
    Abstract: An SOI layer has an initial trench extending therethrough, prior to deep trench etch. An oxidation step, such as thermal oxidation is performed to form a band of oxide on an inner periphery of the SOI layer to protect it during a subsequent RIE step for forming a deep trench. The initial trench may stop on BOX underlying the SOI. The band of oxide may also protect the SOI during buried plate implant or gas phase doping.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: February 7, 2012
    Assignee: International Business Machines Corporation
    Inventors: Thomas W. Dyer, Herbert L. Ho, Ravi M. Todi
  • Patent number: 8053823
    Abstract: A structure is provided herein which includes an array of trench capacitors having at least portions disposed below a buried oxide layer of an SOI substrate. Each trench capacitor shares a common unitary buried capacitor plate which includes at least a portion of a first unitary semiconductor region disposed below the buried oxide layer. An upper boundary of the buried capacitor plate defines a plane parallel to a major surface of the substrate which extends laterally throughout the array of trench capacitors. In a particular embodiment, which starts from either an SOI or a bulk substrate, trenches of the array and a contact hole are formed simultaneously, such that the contact hole extends to substantially the same depth as the trenches. The contact hole preferably has substantially greater width than the trenches such that the conductive contact via can be formed simultaneously by processing used to form trench capacitors extending along walls of the trenches.
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: November 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Herbert L. Ho, Carl J. Radens
  • Patent number: 8008713
    Abstract: A semiconductor memory device in which a vertical trench semiconductor-oxide-nitride-oxide-semiconductor (SONOS) memory cell is created in a semiconductor-on-insulator (SOI) substrate is provided that allows for the integration of dense non-volatile random access memory (NVRAM) cells in SOI-based complementary metal oxide semiconductor (CMOS) technology. The trench is processed using conventional trench processing and it is processed near the beginning of the inventive method that allows for the fabrication of the memory cell to be fully separated from SOI logic processing.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: August 30, 2011
    Assignee: International Business Machines Corporation
    Inventors: David M. Dobuzinsky, Herbert L. Ho, Jack A. Mandelman, Yoichi Otani
  • Publication number: 20110180862
    Abstract: Embodiments of the invention provide an integrated circuit for an embedded dynamic random access memory (eDRAM), a semiconductor-on-insulator (SOI) wafer in which such an integrated circuit may be formed, and a method of forming an eDRAM in such an SOI wafer.
    Type: Application
    Filed: January 25, 2010
    Publication date: July 28, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Brent A. Anderson, John E. Barth, JR., Herbert L. Ho, Edward J. Nowak, Wayne Trickle
  • Publication number: 20110133310
    Abstract: Disclosed is an integrated circuit having at least one deep trench isolation structure and a deep trench capacitor. A method of forming the integrated circuit incorporates a single etch process to simultaneously form first trench(s) and a second trenches for the deep trench isolation structure(s) and a deep trench capacitor, respectively. Following formation of a buried capacitor plate adjacent to the lower portion of the second trench, the trenches are lined with a conformal insulator layer and filled with a conductive material. Thus, for the deep trench capacitor, the conformal insulator layer functions as the capacitor dielectric and the conductive material as a capacitor plate in addition to the buried capacitor plate. A shallow trench isolation (STI) structure formed in the substrate extending across the top of the first trench(es) encapsulates the conductive material therein, thereby creating the deep trench isolation structure(s).
    Type: Application
    Filed: December 3, 2009
    Publication date: June 9, 2011
    Applicant: International Business Machines Corporation
    Inventors: Brent A. Anderson, Andres Bryant, Herbert L. Ho, Edward J. Nowak
  • Patent number: 7951666
    Abstract: Disclosed herein are embodiments of a deep trench capacitor structure and a method of forming the structure that incorporates a buried capacitor plate contact that is simultaneously formed using an adjacent deep trench. This configuration eliminates the need for additional photolithographic processing, thereby, optimizing process windows. This configuration further eliminates the need to form the deep trench capacitor through an N-doped diffusion region connector and, thereby, allows for greater design flexibility when connecting the deep trench capacitor to another integrated circuit structure (e.g., a memory cell or decoupling capacitor array). Also, disclosed herein are embodiments of another integrated circuit structure and method, and more specifically, a memory cell (e.g., a static random access memory (SRAM) cell)) and method of forming the memory cell that incorporates one or more of these deep trench capacitors in order to minimize or eliminate soft errors.
    Type: Grant
    Filed: October 16, 2007
    Date of Patent: May 31, 2011
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Steven M. Shank
  • Publication number: 20110092043
    Abstract: A deep trench is formed to a depth midway into a buried insulator layer of a semiconductor-on-insulator (SOI) substrate. A top semiconductor layer is laterally recessed by an isotropic etch that is selective to the buried insulator layer. The deep trench is then etched below a bottom surface of the buried insulator layer. Ion implantation is performed at an angle into the deep trench to dope the sidewalls of the deep trench beneath the buried insulator layer, while the laterally recessed sidewalls of the top semiconductor layer are not implanted with dopant ions. A node dielectric and trench fill materials are deposited into the deep trench. A buried strap has an upper buried strap sidewall that is offset from a lower buried strap sidewall and a deep trench sidewall.
    Type: Application
    Filed: December 21, 2010
    Publication date: April 21, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: MaryJane Brodsky, Kangguo Cheng, Herbert L. Ho, Paul C. Parries, Kevin R. Winstel
  • Patent number: 7911024
    Abstract: The present invention provides a “collector-less” silicon-on-insulator (SOI) bipolar junction transistor (BJT) that has no impurity-doped collector. Instead, the inventive vertical SOI BJT uses a back gate-induced, minority carrier inversion layer as the intrinsic collector when it operates. In accordance with the present invention, the SOI substrate is biased such that an inversion layer is formed at the bottom of the base region serving as the collector. The advantage of such a device is its CMOS-like process. Therefore, the integration scheme can be simplified and the manufacturing cost can be significantly reduced. The present invention also provides a method of fabricating BJTs on selected areas of a very thin BOX using a conventional SOI starting wafer with a thick BOX. The reduced BOX thickness underneath the bipolar devices allows for a significantly reduced substrate bias compatible with the CMOS to be applied while maintaining the advantages of a thick BOX underneath the CMOS.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: March 22, 2011
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Mahender Kumar, Qiqing Ouyang, Paul A. Papworth, Christopher D. Sheraw, Michael D. Steigerwalt
  • Publication number: 20110042731
    Abstract: A method for forming a memory device in a semiconductor on insulator substrate is provided, in which a protective oxide that is present on the sidewalls of the trench protects the first semiconductor layer, i.e., SOI layer, of the semiconductor on insulator substrate during bottle etching of the trench. In one embodiment, the protective oxide reduces back channel effects of the transistors to the memory devices in the trench that are formed in the semiconductor on insulator substrate. In another embodiment, a thermal oxidation process increases the thickness of the buried dielectric layer of a bonded semiconductor on insulator substrate by oxidizing the bonded interface between the buried dielectric layer and at least one semiconductor layers of the semiconductor on insulator substrate. The increased thickness of the buried dielectric layer may reduce back channel effects in devices formed on the substrate having trench memory structures.
    Type: Application
    Filed: August 21, 2009
    Publication date: February 24, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Herbert L. Ho, Naoyoshi Kusaba, Karen A. Nummy, Carl J. Radens, Ravi M. Todi, Geng Wang
  • Patent number: 7893485
    Abstract: A semiconductor memory device and a design structure including the semiconductor memory device embodied in a machine readable medium is provided. In particular the present invention includes a semiconductor memory device in which a vertical trench semiconductor-oxide-nitride-oxide-semiconductor (SONOS) memory cell is created in a semiconductor-on-insulator (SOI) substrate is provided that allows for the integration of dense non-volatile random access memory (NVRAM) cells in SOI-based complementary metal oxide semiconductor (CMOS) technology. The trench is processed using conventional trench processing and it is processed near the beginning of the inventive method that allows for the fabrication of the memory cell to be fully separated from SOI logic processing.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: February 22, 2011
    Assignee: International Business Machines Corporation
    Inventors: David M. Dobuzinsky, Herbert L. Ho, Jack A. Mandelman, Yoichi Otani
  • Patent number: 7888723
    Abstract: A deep trench is formed to a depth midway into a buried insulator layer of a semiconductor-on-insulator (SOI) substrate. A top semiconductor layer is laterally recessed by an isotropic etch that is selective to the buried insulator layer. The deep trench is then etched below a bottom surface of the buried insulator layer. Ion implantation is performed at an angle into the deep trench to dope the sidewalls of the deep trench beneath the buried insulator layer, while the laterally recessed sidewalls of the top semiconductor layer are not implanted with dopant ions. A node dielectric and trench fill materials are deposited into the deep trench. A buried strap has an upper buried strap sidewall that is offset from a lower buried strap sidewall and a deep trench sidewall.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: February 15, 2011
    Assignee: International Business Machines Corporation
    Inventors: MaryJane Brodsky, Kangguo Cheng, Herbert L. Ho, Paul C. Parries, Kevin R. Winstel
  • Publication number: 20100283093
    Abstract: A memory device is provided that in one embodiment includes a trench capacitor located in a semiconductor substrate including an outer electrode provided by the semiconductor substrate, an inner electrode provided by a conductive fill material, and a node dielectric layer located between the outer electrode and the inner electrode; and a semiconductor device positioned centrally over the trench capacitor. The semiconductor device includes a source region, a drain region, and a gate structure, in which the semiconductor device is formed on a semiconductor layer that is separated from the semiconductor substrate by a dielectric layer. A first contact is present extending from an upper surface of the semiconductor layer into electrical contact with the semiconductor substrate, and a second contact from the drain region of the semiconductor device in electrical contact to the conductive material within the at least one trench.
    Type: Application
    Filed: May 7, 2009
    Publication date: November 11, 2010
    Applicant: International Business Machines Corporation
    Inventors: Chengwen Pei, Kangguo Cheng, Herbert L. Ho, Subramanian S. Iyer, Byeong Y. Kim, Geng Wang, Huilong Zhu