Patents by Inventor Christophe Pierrat

Christophe Pierrat 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: 20100251202
    Abstract: The manufacturing of integrated circuits relies on the use of lithography simulation to predict the image of the mask created on the wafer. Such predictions can be used for example to assess the quality of the images, verify the manufacturability of such images, perform using OPC necessary correction of the mask data to achieve images close to the targets, optimize the printing parameters such as the illumination source, or globally optimize the source and the mask to achieve better printability. This disclosure provides a technique based on the association of at least one kernel function per source region or source point. Each kernel function can be directly convoluted with a mask image to create a prediction of the wafer image. As the kernel functions are associated with the source, the source can be easily changed to create new models. The optical system can be fully described by computing the possible kernels for all possible source points and all possible numerical apertures.
    Type: Application
    Filed: March 24, 2010
    Publication date: September 30, 2010
    Inventor: Christophe Pierrat
  • Publication number: 20100218156
    Abstract: According to various embodiments of the invention, systems and methods for system and methods for compressed post-OPC data created during the design and manufacturing of integrated circuits. In one embodiment of the invention, the method begins by generating a post-OPC layout from a circuit layout during the design phase of a circuit. This post-OPC layout is generated by way of an OPC process. Next, a set of differences between the post-OPC layout and the circuit layout are calculated and a dataset containing these differences are generated In some embodiments the dataset is generated during the OPC process.
    Type: Application
    Filed: February 23, 2009
    Publication date: August 26, 2010
    Inventor: Christophe PIERRAT
  • Patent number: 7739649
    Abstract: A method for defining a full phase layout for defining a layer of material in an integrated circuit is described. The method can be used to define, arrange, and refine phase shifters to substantially define the layer using phase shifting. Through the process, computer readable definitions of an alternating aperture, dark field phase shift mask and of a complimentary mask are generated. Masks can be made from the definitions and then used to fabricate a layer of material in an integrated circuit. The separations between phase shifters, or cuts, are designed for easy mask manufacturability while also maximizing the amount of each feature defined by the phase shifting mask. Cost functions are used to describe the relative quality of phase assignments and to select higher quality phase assignments and reduce phase conflicts.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: June 15, 2010
    Assignee: Synopsys, Inc.
    Inventors: Michel L. Cote, Christophe Pierrat
  • Publication number: 20100050149
    Abstract: A method for defining a full phase layout for defining a layer of material in an integrated circuit is described. The method can be used to define, arrange, and refine phase shifters to substantially define the layer using phase shifting. Through the process, computer readable definitions of an alternating aperture, dark field phase shift mask and of a complimentary mask are generated. Masks can be made from the definitions and then used to fabricate a layer of material in an integrated circuit. The separations between phase shifters, or cuts, are designed for easy mask manufacturability while also maximizing the amount of each feature defined by the phase shifting mask. Cost functions are used to describe the relative quality of phase assignments and to select higher quality phase assignments and reduce phase conflicts.
    Type: Application
    Filed: October 30, 2009
    Publication date: February 25, 2010
    Applicant: Synopsys, Inc.
    Inventors: Michel L. Cote, Christophe Pierrat
  • Publication number: 20100040965
    Abstract: Mask and integrated circuit fabrication approaches are described to facilitate use of so called “full phase” masks. This facilitates use of masks where substantially all of a layout is defined using phase shifting. In one embodiment, the phase shifting mask and the trim mask are exposed using substantially the same exposure conditions. These approaches facilitate better exposure profiles for the resulting ICs and can thus improve chip yield and increase throughput by reducing the need to alter settings and/or switch reticles between exposures.
    Type: Application
    Filed: October 16, 2009
    Publication date: February 18, 2010
    Applicant: Synopsys, Inc.
    Inventors: Christophe Pierrat, Michel Luc Cote
  • Patent number: 7659042
    Abstract: A full phase shifting mask (FPSM) can be advantageously used in a damascene process for hard-to-etch metal layers. Because the FPSM can be used with a positive photoresist, features on an original layout can be replaced with shifters on a FPSM layout. Adjacent shifters should be of opposite phase, e.g. 0 and 180 degrees. In one embodiment, a dark field trim mask can be used with the FPSM. The trim mask can include cuts that correspond to cuts on the FPSM. Cuts on the FPSM can be made to resolve phase conflicts between proximate shifters. In one case, exposing two proximate shifters on the FPSM and a corresponding cut on the trim mask can form a feature in the metal layer. The FPSM and/or the trim mask can include proximity corrections to further improve printing resolution.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: February 9, 2010
    Assignee: Synopsys, Inc.
    Inventor: Christophe Pierrat
  • Patent number: 7629109
    Abstract: Mask and integrated circuit fabrication approaches are described to facilitate use of so called “full phase” masks. This facilitates use of masks where substantially all of a layout is defined using phase shifting. In one embodiment, the phase shifting mask and the trim mask are exposed using substantially the same exposure conditions. These approaches facilitate better exposure profiles for the resulting ICs and can thus improve chip yield and increase throughput by reducing the need to alter settings and/or switch reticles between exposures.
    Type: Grant
    Filed: April 7, 2008
    Date of Patent: December 8, 2009
    Assignee: Synopsys, Inc.
    Inventors: Christophe Pierrat, Michel Luc Cote
  • Patent number: 7614033
    Abstract: The manufacturing of integrated circuits relies on the use of optical proximity correction (OPC) to correct the printing of the features on the wafer. The data is subsequently fractured to accommodate the format of existing mask writer. The complexity of the correction after OPC can create some issues for vector-scan e-beam mask writing tools as very small slivers are created when the data is converted to the mask write tool format. Moreover the number of shapes created after fracturing is quite large and are not related to some important characteristics of the layout like for example critical areas. A new technique is proposed where the order of the OPC and fracturing steps is reversed. The fracturing step is done first in order to guarantee that no slivers are created and that the number of shapes is minimized. The shapes created can also follow the edges of critical zones so that critical and non-critical edges can be differentiated during the subsequent OPC step.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: November 3, 2009
    Assignee: Takumi Technology Corp.
    Inventors: Christophe Pierrat, Alfred Kwok-Kit Wong
  • Publication number: 20090249266
    Abstract: Techniques for forming a mask fabrication layout for a physical integrated circuit design layout include correcting the fabrication layout for proximity effects using a proximity effects model. A proximity effects model is executed to produce an initial output. The initial output is based on a first position for a segment in a fabrication layout. The first position is displaced from a corresponding original edge in the original fabrication layout by a distance equal to an initial bias. The model is also executed to produce a second output based on a second position for the segment. The second position is displaced from the corresponding original edge by a distance equal to a second bias. An optimal bias for the segment is determined based on the initial output and the second output. The segment is displaced in the fabrication layout from the corresponding edge based on the optimal bias.
    Type: Application
    Filed: June 10, 2009
    Publication date: October 1, 2009
    Applicant: Synopsys, Inc.
    Inventors: Christophe Pierrat, Youping Zhang
  • Patent number: 7585595
    Abstract: A method extends the use of phase shift techniques to complex layouts, and includes identifying a pattern, and automatically mapping the phase shifting regions for implementation of such features. The pattern includes small features having a dimension smaller than a first particular feature size, and at least one relatively large feature, the at least one relatively large feature and another feature in the pattern having respective sides separated by a narrow space. Phase shift regions are laid out including a first set of phase shift regions to define said small features, and a second set of phase shift regions to assist definition of said side of said relatively large feature. An opaque feature is used to define the relatively large feature, and a phase shift region in the second set is a sub-resolution window inside the perimeter of the opaque feature.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: September 8, 2009
    Assignee: Synopsys, Inc.
    Inventor: Christophe Pierrat
  • Patent number: 7562319
    Abstract: Techniques for forming a mask fabrication layout for a physical integrated circuit design layout include correcting the fabrication layout for proximity effects using a proximity effects model. A proximity effects model is executed to produce an initial output. The initial output is based on a first position for a segment in a fabrication layout. The first position is displaced from a corresponding original edge in the original fabrication layout by a distance equal to an initial bias. The model is also executed to produce a second output based on a second position for the segment. The second position is displaced from the corresponding original edge by a distance equal to a second bias. An optimal bias for the segment is determined based on the initial output and the second output. The segment is displaced in the fabrication layout from the corresponding edge based on the optimal bias.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: July 14, 2009
    Assignee: Synopsys, Inc.
    Inventors: Christophe Pierrat, Youping Zhang
  • Patent number: 7534531
    Abstract: A full phase shifting mask (FPSM) can be advantageously used in a damascene process for hard-to-etch metal layers. Because the FPSM can be used with a positive photoresist, features on an original layout can be replaced with shifters on a FPSM layout. Adjacent shifters should be of opposite phase, e.g. 0 and 180 degrees. In one embodiment, a dark field trim mask can be used with the FPSM. The trim mask can include cuts that correspond to cuts on the FPSM. Cuts on the FPSM can be made to resolve phase conflicts between proximate shifters. In one case, exposing two proximate shifters on the FPSM and a corresponding cut on the trim mask can form a feature in the metal layer. The FPSM and/or the trim mask can include proximity corrections to further improve printing resolution.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: May 19, 2009
    Assignee: Synopsys, Inc.
    Inventor: Christophe Pierrat
  • Publication number: 20090125867
    Abstract: Definition of a phase shifting layout from an original layout can be time consuming. If the original layout is divided into useful groups, i.e. clusters that can be independently processed, then the phase shifting process can be performed more rapidly. If the shapes on the layout are enlarged, then the overlapping shapes can be grouped together to identify shapes that should be processed together. For large layouts, growing and grouping the shapes can be time consuming. Therefore, an approach that uses bins can speed up the clustering process, thereby allowing the phase shifting to be performed in parallel on multiple computers. Additional efficiencies result if identical clusters are identified and processing time saved so that repeated clusters of shapes only undergo the computationally expensive phase shifter placement and assignment process a single time.
    Type: Application
    Filed: January 12, 2009
    Publication date: May 14, 2009
    Applicant: Synopsys, Inc.
    Inventors: Michel L. Cote, Christophe Pierrat
  • Patent number: 7500217
    Abstract: Definition of a phase shifting layout from an original layout can be time consuming. If the original layout is divided into useful groups, i.e. clusters that can be independently processed, then the phase shifting process can be performed more rapidly. If the shapes on the layout are enlarged, then the overlapping shapes can be grouped together to identify shapes that should be processed together. For large layouts, growing and grouping the shapes can be time consuming. Therefore, an approach that uses bins can speed up the clustering process, thereby allowing the phase shifting to be performed in parallel on multiple computers. Additional efficiencies result if identical clusters are identified and processing time saved so that repeated clusters of shapes only undergo the computationally expensive phase shifter placement and assignment process a single time.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: March 3, 2009
    Assignee: Synopsys, Inc.
    Inventors: Michel Luc Côté, Christophe Pierrat
  • Patent number: 7458056
    Abstract: Proximity effect correction has become a necessary step in the fabrication of integrated circuit in order to improve the pattern fidelity of current lithography processes. Current methodology is limited by data volume increase and correction inaccuracy due to extrapolation of the correction. The invention describes a methodology based on the interpolation of the correction between selected evaluation points of the target layout. By connecting the correction points this technique also provides a mean of reducing data volume and simplifying the mask writing, inspection and repair processes. The same methodology can be applied to layouts with non-printing assist features, where the correction of the assist features is based on the quality of the image of the main feature. For vector-scan mask write tool the segments interpolating the corrections can be fractured in segments with suitable angles.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: November 25, 2008
    Assignee: Takumi Technology Corp.
    Inventor: Christophe Pierrat
  • Publication number: 20080286664
    Abstract: A full phase shifting mask (FPSM) can be advantageously used in a damascene process for hard-to-etch metal layers. Because the FPSM can be used with a positive photoresist, features on an original layout can be replaced with shifters on a FPSM layout. Adjacent shifters should be of opposite phase, e.g. 0 and 180 degrees. In one embodiment, a dark field trim mask can be used with the FPSM. The trim mask can include cuts that correspond to cuts on the FPSM. Cuts on the FPSM can be made to resolve phase conflicts between proximate shifters. In one case, exposing two proximate shifters on the FPSM and a corresponding cut on the trim mask can form a feature in the metal layer. The FPSM and/or the trim mask can include proximity corrections to further improve printing resolution.
    Type: Application
    Filed: July 31, 2008
    Publication date: November 20, 2008
    Applicant: Synopsys, Inc.
    Inventor: Christophe Pierrat
  • Patent number: 7435513
    Abstract: A method for defining a full phase layout for defining a layer of material in an integrated circuit is described. The method can be used to define, arrange, and refine phase shifters to substantially define the layer using phase shifting. Through the process, computer readable definitions of an alternating aperture, dark field phase shift mask and of a complimentary mask are generated. Masks can be made from the definitions and then used to fabricate a layer of material in an integrated circuit. The separations between phase shifters, or cuts, are designed for easy mask manufacturability while also maximizing the amount of each feature defined by the phase shifting mask. Cost functions are used to describe the relative quality of phase assignments and to select higher quality phase assignments and reduce phase conflicts.
    Type: Grant
    Filed: September 10, 2004
    Date of Patent: October 14, 2008
    Assignee: Synopsys, Inc.
    Inventors: Michel L. Cote, Christophe Pierrat
  • Patent number: 7422841
    Abstract: Mask and integrated circuit fabrication approaches are described to facilitate use of masks where substantially all of a layout is defined using phase shifting. Exposure settings including relative dosing between the phase shift mask and the trim masks are described. Additionally, single reticle approaches for accommodating both masks are considered. In one embodiment, the phase shifting mask and the trim mask are exposed using the same exposure conditions that have an effect on the characteristics of the radiation used for the exposure, except for relative dosing. The same exposure conditions are changeable optical parameters that consist of numerical aperture (N.A.), wavelength (?) of radiation, partial coherency (?), illumination configuration, and defocus. These approaches facilitate better exposure profiles for the resulting ICs and can thus improve chip yield and increase throughput by reducing the need to alter settings and/or switch reticles between exposures.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: September 9, 2008
    Assignee: Synopsys, Inc.
    Inventors: Christophe Pierrat, Michel Luc Cote
  • Publication number: 20080187869
    Abstract: Mask and integrated circuit fabrication approaches are described to facilitate use of so called “full phase” masks. This facilitates use of masks where substantially all of a layout is defined using phase shifting. More specifically, exposure settings including relative dosing between the phase shift mask and the trim masks are described. Additionally, single reticle approaches for accommodating both masks are considered. In one embodiment, the phase shifting mask and the trim mask are exposed using the same exposure conditions, except for relative dosing. In another embodiment, the relative dosing between the phase and trim patterns is 1.0:r, 2.0<r<4.0. These approaches facilitate better exposure profiles for the resulting ICs and can thus improve chip yield and increase throughput by reducing the need to alter settings and/or switch reticles between exposures.
    Type: Application
    Filed: April 7, 2008
    Publication date: August 7, 2008
    Applicant: Synopsys, Inc.
    Inventors: Christophe Pierrat, Michel Luc Cote
  • Publication number: 20080076042
    Abstract: A method for defining a full phase layout for defining a layer of material in an integrated circuit is described. The method can be used to define, arrange, and refine phase shifters to substantially define the layer using phase shifting. Through the process, computer readable definitions of an alternating aperture, dark field phase shift mask and of a complimentary mask are generated. Masks can be made from the definitions and then used to fabricate a layer of material in an integrated circuit. The separations between phase shifters, or cuts, are designed for easy mask manufacturability while also maximizing the amount of each feature defined by the phase shifting mask. Cost functions are used to describe the relative quality of phase assignments and to select higher quality phase assignments and reduce phase conflicts.
    Type: Application
    Filed: October 29, 2007
    Publication date: March 27, 2008
    Applicant: Synopsys, Inc.
    Inventors: Michel Cote, Christophe Pierrat