Patents by Inventor Shankar Kumar Selvaraja

Shankar Kumar Selvaraja 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: 9791621
    Abstract: A method for fabricating an integrated semiconductor photonics device is disclosed. The method may include providing a first substrate having on its top surface a monocrystalline semiconductor layer suitable for supporting an optical mode and forming a homogenous and conformal first dielectric layer on a planar surface of the monocrystalline semiconductor layer. The method may further include providing a dielectric waveguide core on the first dielectric layer, the dielectric waveguide core optically coupled to a first region of the monocrystalline semiconductor layer through the first dielectric layer. The method may further include depositing a second dielectric layer on the dielectric waveguide core, thereby covering the dielectric waveguide core, and annealing the substrate to drive hydrogen out of the dielectric waveguide core.
    Type: Grant
    Filed: December 16, 2015
    Date of Patent: October 17, 2017
    Assignee: IMEC VZW
    Inventors: Philippe Absil, Shankar Kumar Selvaraja
  • Patent number: 9632248
    Abstract: The present invention relates to an integrated photonic device comprising a photonic substrate, and an integrated waveguide provided in or on this substrate. The waveguide is adapted for conducting radiation of a predetermined wavelength. The device further comprises a sub-wavelength grating optically connected to the waveguide, which provides a first periodic variation of the refractive index in at least one first spatial direction. The device also comprises a diffracting grating arranged over the sub-wavelength grating for coupling radiation of the predetermined wavelength in and/or out of the integrated waveguide via the sub-wavelength grating. The diffracting grating provides a second periodic variation of the refractive index in at least one second spatial direction. The first periodic variation has a first pitch that is less than half of the predetermined wavelength, while the second periodic variation has a second pitch that is at least half of the predetermined wavelength.
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: April 25, 2017
    Assignees: IMEC VZW, Universiteit Gent
    Inventor: Shankar Kumar Selvaraja
  • Publication number: 20160170139
    Abstract: A method for fabricating an integrated semiconductor photonics device is disclosed. The method may include providing a first substrate having on its top surface a monocrystalline semiconductor layer suitable for supporting an optical mode and forming a homogenous and conformal first dielectric layer on a planar surface of the monocrystalline semiconductor layer. The method may further include providing a dielectric waveguide core on the first dielectric layer, the dielectric waveguide core optically coupled to a first region of the monocrystalline semiconductor layer through the first dielectric layer. The method may further include depositing a second dielectric layer on the dielectric waveguide core, thereby covering the dielectric waveguide core, and annealing the substrate to drive hydrogen out of the dielectric waveguide core.
    Type: Application
    Filed: December 16, 2015
    Publication date: June 16, 2016
    Applicant: IMEC VZW
    Inventors: Philippe Absil, Shankar Kumar Selvaraja
  • Publication number: 20150285996
    Abstract: The present invention relates to an integrated photonic device comprising a photonic substrate, and an integrated waveguide provided in or on this substrate. The waveguide is adapted for conducting radiation of a predetermined wavelength. The device further comprises a sub-wavelength grating optically connected to the waveguide, which provides a first periodic variation of the refractive index in at least one first spatial direction. The device also comprises a diffracting grating arranged over the sub-wavelength grating for coupling radiation of the predetermined wavelength in and/or out of the integrated waveguide via the sub-wavelength grating. The diffracting grating provides a second periodic variation of the refractive index in at least one second spatial direction. The first periodic variation has a first pitch that is less than half of the predetermined wavelength, while the second periodic variation has a second pitch that is at least half of the predetermined wavelength.
    Type: Application
    Filed: December 22, 2014
    Publication date: October 8, 2015
    Applicants: Universiteit Gent, IMEC VZW
    Inventor: Shankar Kumar Selvaraja
  • Patent number: 9039907
    Abstract: A method is described for improving the uniformity over a predetermined substrate area of a spectral response of photonic devices fabricated in a thin device layer. The method includes (i) establishing an initial device layer thickness map for the predetermined area, (ii) establishing a linewidth map for the predetermined area, and (iii) establishing an etch depth map for the predetermined area. The method further includes, based on the initial device layer thickness map, the linewidth map and the etch depth map, calculating an optimal device layer thickness map and a corresponding thickness correction map for the predetermined substrate area taking into account photonic device design data. Still further, the method includes performing a location specific corrective etch process in accordance with the thickness correction map.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: May 26, 2015
    Assignees: IMEC, Universiteit Gent
    Inventors: Philippe Absil, Shankar Kumar Selvaraja
  • Publication number: 20130023067
    Abstract: A method is described for improving the uniformity over a predetermined substrate area of a spectral response of photonic devices fabricated in a thin device layer. The method includes (i) establishing an initial device layer thickness map for the predetermined area, (ii) establishing a linewidth map for the predetermined area, and (iii) establishing an etch depth map for the predetermined area. The method further includes, based on the initial device layer thickness map, the linewidth map and the etch depth map, calculating an optimal device layer thickness map and a corresponding thickness correction map for the predetermined substrate area taking into account photonic device design data. Still further, the method includes performing a location specific corrective etch process in accordance with the thickness correction map.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 24, 2013
    Applicant: IMEC
    Inventors: Philippe Absil, Shankar Kumar Selvaraja