Patents by Inventor Atul Ajmera

Atul Ajmera 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: 7741165
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: June 22, 2010
    Assignee: International Business Machines Corporation
    Inventors: Kevin Kok Chan, Robert J. Miller, Erin C. Jones, Atul Ajmera
  • Publication number: 20080248635
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Application
    Filed: May 12, 2008
    Publication date: October 9, 2008
    Applicant: International Business Machines Corporation
    Inventors: Kevin Kok Chan, Rober J. Miller, Erin C. Jones, Atul Ajmera
  • Patent number: 7387924
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Grant
    Filed: September 18, 2006
    Date of Patent: June 17, 2008
    Assignee: International Business Machines Corporation
    Inventors: Kevin Kok Chan, Robert J. Miller, Erin C. Jones, Atul Ajmera
  • Publication number: 20070254420
    Abstract: Methods for source/drain implantation and strain transfer to a channel of a semiconductor device and a related semiconductor device are disclosed. In one embodiment, the method includes using a first size spacer for deep source/drain implantation adjacent a gate region of a semiconductor device; and using a second, smaller size spacer for silicide formation adjacent the gate region and transferring strain from a stress liner to a channel underlying the gate region. One embodiment of a semiconductor device may include a gate region atop a substrate; a spacer including a spacer core and an outer spacer member about the spacer core; a deep source/drain region within the substrate and distanced from the spacer; and a silicide region within the substrate and overlapping and extending beyond the deep source/drain region, the silicide region aligned to the spacer.
    Type: Application
    Filed: April 28, 2006
    Publication date: November 1, 2007
    Applicants: International Business Machines Corporation, Chartered Semiconductor Manufacturing LTD.
    Inventors: Atul Ajmera, Christopher Baiocco, Xiangdong Chen, Thomas Dyer, Sunfei Fang, Wenzhi Gao
  • Publication number: 20070202654
    Abstract: Process for enhancing strain in a channel with a stress liner, spacer, process for forming integrated circuit and integrated circuit. A first spacer composed of an first oxide and first nitride layer is applied to a gate electrode on a substrate, and a second spacer composed of a second oxide and second nitride layer is applied. Deep implanting of source and drain in the substrate occurs, and removal of the second nitride, second oxide, and first nitride layers.
    Type: Application
    Filed: February 28, 2006
    Publication date: August 30, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Atul Ajmera, Christopher Baiocco, Xiangdong Chen, Wenzhi Gao, Young Way Teh
  • Publication number: 20070122988
    Abstract: A method of forming a semiconductor device that embeds an L-shaped spacer is provided. The method includes defining an L-shaped spacer on each side of a gate region of a substrate and embedding the L-shaped spacers in an oxide layer so that the oxide layer extends over a portion of the substrate a predetermined distance from a lateral edge of the L-shaped spacer. And removing oxide layers to expose the L-shape spacers.
    Type: Application
    Filed: November 29, 2005
    Publication date: May 31, 2007
    Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION, CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Zhijiong Luo, Young Teh, Atul Ajmera
  • Publication number: 20070010076
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Application
    Filed: September 18, 2006
    Publication date: January 11, 2007
    Applicant: International Business Machines Corporation
    Inventors: Kevin Chan, Rober Miller, Erin Jones, Atul Ajmera
  • Patent number: 7135391
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: November 14, 2006
    Assignee: International Business Machines Corporation
    Inventors: Kevin Kok Chan, Rober J. Miller, Erin C. Jones, Atul Ajmera
  • Publication number: 20060057797
    Abstract: A method for forming a CMOS device in a manner so as to avoid dielectric layer undercut during a pre-silicide cleaning step is described. During formation of CMOS device comprising a gate stack on a semiconductor substrate surface, the patterned gate stack including gate dielectric below a conductor with vertical sidewalls, a dielectric layer is formed thereover and over the substrate surfaces. Respective nitride spacer elements overlying the dielectric layer are formed at each vertical sidewall. The dielectric layer on the substrate surface is removed using an etch process such that a portion of the dielectric layer underlying each spacer remains. Then, a nitride layer is deposited over the entire sample (the gate stack, the spacer elements at each gate sidewall, and substrate surfaces) and subsequently removed by an etch process such that only a portion of said nitride film (the “plug”) remains.
    Type: Application
    Filed: November 4, 2005
    Publication date: March 16, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Atul Ajmera, Andres Bryant, Percy Gilbert, Michael Gribelyuk, Edward Maciejewski, Renee Mo, Shreesh Narasimha
  • Publication number: 20050260832
    Abstract: A structure and method of fabrication for MOSFET devices with a polycrystalline SiGe junction is disclosed. Ge is selectively grown on Si while Si is selectively grown on Ge. Alternating depositions of Ge and Si layers yield the SiGe junction. The deposited layers are doped, and subsequently the dopants outdiffused into the device body. A thin porous oxide layer between the polycrystalline Ge and Si layers enhances the isotropy of the SiGe junctions.
    Type: Application
    Filed: May 21, 2004
    Publication date: November 24, 2005
    Inventors: Kevin Chan, Rober Miller, Erin Jones, Atul Ajmera
  • Publication number: 20050064635
    Abstract: A method for forming a CMOS device in a manner so as to avoid dielectric layer undercut during a pre-silicide cleaning step is described. During formation of CMOS device comprising a gate stack on a semiconductor substrate surface, the patterned gate stack including gate dielectric below a conductor with vertical sidewalls, a dielectric layer is formed thereover and over the substrate surfaces. Respective nitride spacer elements overlying the dielectric layer are formed at each vertical sidewall. The dielectric layer on the substrate surface is removed using an etch process such that a portion of the dielectric layer underlying each spacer remains. Then, a nitride layer is deposited over the entire sample (the gate stack, the spacer elements at each gate sidewall, and substrate surfaces) and subsequently removed by an etch process such that only a portion of said nitride film (the “plug”) remains.
    Type: Application
    Filed: September 22, 2003
    Publication date: March 24, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Atul Ajmera, Andres Bryant, Percy Gilbert, Michael Gribelyuk, Edward Maciejewski, Renee Mo, Shreesh Narasimha
  • Patent number: 6521947
    Abstract: A method for forming a substrate contact in a substrate that includes a silicon on insulator region. A shallow isolation trench is formed in the silicon on insulator substrate. The shallow isolation trench is filled. Photoresist is deposited on the substrate. A contact trench is formed in the substrate through the filled shallow isolation trench, silicon on insulator, and silicon substrate underlying the silicon on insulator region. The contact trench is filled, wherein the material filling the contact trench forms a contact to the silicon substrate.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: February 18, 2003
    Assignee: International Business Machines Corporation
    Inventors: Atul Ajmera, Effendi Leobandung, Werner Rausch, Dominic J. Schepis, Ghavam G. Shahidi
  • Publication number: 20010041395
    Abstract: A process for forming a planar silicon-on-insulator (SOI) substrate comprising a patterned SOI region and a bulk region, wherein the substrate is free of transitional defects. The process comprises removing the transitional defects by creating a self-aligned trench adjacent the SOI region between the SOI region and the bulk region.
    Type: Application
    Filed: June 5, 2001
    Publication date: November 15, 2001
    Inventors: Atul Ajmera, Devendra K. Sadana, Dominic J. Schepis
  • Patent number: 6255145
    Abstract: A process for forming a planar silicon-on-insulator (SOI) substrate comprising a patterned SOI region and a bulk region, wherein the substrate is free of transitional defects. The process comprises removing the transitional defects by creating a self-aligned trench adjacent the SOI region between the SOI region and the bulk region.
    Type: Grant
    Filed: January 8, 1999
    Date of Patent: July 3, 2001
    Assignee: International Business Machines Corporation
    Inventors: Atul Ajmera, Devendra K. Sadana, Dominic J. Schepis
  • Patent number: 5747866
    Abstract: Silicon integrated circuits use a crystalline layer of silicon nitride (Si.sub.3 N.sub.4) in shallow trench isolation (STI) structures as an O.sub.2 -barrier film. The crystalline Si.sub.3 N.sub.4 lowers the density of electron traps as compared with as-deposited, amorphous Si.sub.3 N.sub.4. Further, a larger range of low-pressure chemical-vapor deposited (LPCVD) Si.sub.3 N.sub.4 films can be deposited, providing a larger processing window for thickness controllability. An LPCVD-Si.sub.3 N.sub.4 film is deposited at temperatures of 720.degree. C. to 780.degree. C. The deposited film is in an amorphous state. Subsequently, a high-temperatures rapid-thermal anneal in pure nitrogen or ammonia is conducted at 1050.degree. C. to 1100.degree. for 60 seconds.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: May 5, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventors: Herbert Ho, Erwin Hammerl, David M. Dobuzinsky, Herbert Palm, Stephen Fugardi, Atul Ajmera, James F. Moseman, Samuel C. Ramac
  • Patent number: 5643823
    Abstract: Silicon integrated circuits use a crystalline layer of silicon nitride (Si.sub.3 N.sub.4) in shallow trench isolation (STI) structures as an O.sub.2 -barrier film. The crystalline Si.sub.3 N.sub.4 lowers the density of electron traps as compared with as-deposited, amorphous Si.sub.3 N.sub.4. Further, a larger range of low-pressure chemical-vapor deposited (LPCVD) Si.sub.3 N.sub.4 films can be deposited, providing a larger processing window for thickness controllability. An LPCVD-Si.sub.3 N.sub.4 film is deposited at temperatures of 720.degree. C. to 780.degree. C. The deposited film is in an amorphous state. Subsequently, a high-temperatures rapid-thermal anneal in pure nitrogen or ammonia is conducted at 1050.degree. C. to 1100.degree. C. for 60 seconds.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: July 1, 1997
    Assignees: Siemens Aktiengesellschaft, International Business Machines Corporation
    Inventors: Herbert Ho, Erwin Hammerl, David M. Dobuzinsky, J. Herbert Palm, Stephen Fugardi, Atul Ajmera, James F. Moseman, Samuel C. Ramac