Patents by Inventor Thamarai S. Devarajan

Thamarai S. Devarajan 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: 20180090385
    Abstract: A method for uniform fin reveal depth for semiconductor devices includes dry etching a dielectric material to reveal semiconductor fins by a quasi-atomic layer etching (quasi-ALE) process to achieve depth uniformity across different fin pitches. A lateral bias induced by the quasi-ALE process is compensated for by isotropically etching the dielectric material.
    Type: Application
    Filed: September 28, 2017
    Publication date: March 29, 2018
    Inventors: Zhenxing Bi, Donald F. Canaperi, Thamarai S. Devarajan, Sivananda K. Kanakasabapathy, Fee Li Lie, Peng Xu
  • Publication number: 20170263503
    Abstract: A semiconductor device that includes a first plurality of fin structures in a first device region and a second plurality of fin structures in a second device region. The first plurality of fin structures includes adjacent fin structures separated by a lesser pitch than the adjacent fin structures in the second plurality of fin structures. At least one layer of dielectric material between adjacent fin structures, wherein a portion of the first plurality of fin structures extending above the at least one layer of dielectric material in the first device region is substantially equal to the portion of the second plurality of fin structures extending above the at least one layer of dielectric material in the second device region. Source and drain regions are present on opposing sides of a gate structure that is present on the fin structures.
    Type: Application
    Filed: April 14, 2017
    Publication date: September 14, 2017
    Inventors: Zhenxing Bi, Kangguo Cheng, Thamarai S. Devarajan, Balasubramanian Pranatharthiharan
  • Patent number: 9754798
    Abstract: A method for uniform fin reveal depth for semiconductor devices includes dry etching a dielectric material to reveal semiconductor fins by a quasi-atomic layer etching (quasi-ALE) process to achieve depth uniformity across different fin pitches. A lateral bias induced by the quasi-ALE process is compensated for by isotropically etching the dielectric material.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: September 5, 2017
    Assignee: International Business Machines Corporation
    Inventors: Zhenxing Bi, Donald F. Canaperi, Thamarai S. Devarajan, Sivananda K. Kanakasabapathy, Fee Li Lie, Peng Xu
  • Patent number: 9691765
    Abstract: A semiconductor device that includes a first plurality of fin structures in a first device region and a second plurality of fin structures in a second device region. The first plurality of fin structures includes adjacent fin structures separated by a lesser pitch than the adjacent fin structures in the second plurality of fin structures. At least one layer of dielectric material between adjacent fin structures, wherein a portion of the first plurality of fin structures extending above the at least one layer of dielectric material in the first device region is substantially equal to the portion of the second plurality of fin structures extending above the at least one layer of dielectric material in the second device region. Source and drain regions are present on opposing sides of a gate structure that is present on the fin structures.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: June 27, 2017
    Assignee: International Business Machines Corporation
    Inventors: Zhenxing Bi, Kangguo Cheng, Thamarai S. Devarajan, Balasubramanian Pranatharthiharan
  • Patent number: 9679780
    Abstract: A method is presented for forming a semiconductor device. The method includes depositing a sacrificial layer on a fin structure formed on a substrate and then filled with polysilicon, etching a portion of the polysilicon material via a first etching process, and pre-cleaning the surface native oxide layer. The method further includes etching the remaining polysilicon material via a second etching process, and removing polysilicon etch residue formed adjacent the fin structure by a cleaning process. The pre-cleaning is performed by applying NH3 (ammonia) and NF3 (nitrogen trifluoride) or by applying BHF (buffered hydrofluoric acid). The first etching process is RIE (reactive ion etching) and the second etching process involves applying NF3 and H2 (hydrogen gas).
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: June 13, 2017
    Assignee: International Business Machines Corporation
    Inventors: Zhenxing Bi, Donald F. Canaperi, Thamarai S. Devarajan, Nicolas J. Loubet