Patents by Inventor Dipankar Pramanik

Dipankar Pramanik 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: 20150064873
    Abstract: An internal electrical field in a resistive memory element can be formed to reduce the forming voltage. The internal electric field can be formed by incorporating one or more charged layers within the switching dielectric layer of the resistive memory element. The charged layers can include adjacent charge layers to form dipole layers. The charged layers can be formed at or near the interface of the switching dielectric layer with an electrode layer. Further, the charged layer can be oriented with lower valence substitution side towards lower work function electrode, and higher valence substitution side towards higher work function electrode.
    Type: Application
    Filed: October 29, 2014
    Publication date: March 5, 2015
    Inventors: Sergey Barabash, Charlene Chen, Dipankar Pramanik
  • Publication number: 20150056749
    Abstract: Embodiments of the invention generally relate to nonvolatile memory devices, such as a ReRAM cells, and methods for manufacturing such memory devices, which includes optimized, atomic layer deposition (ALD) processes for forming metal oxide film stacks. The metal oxide film stacks contain a metal oxide coupling layer disposed on a metal oxide host layer, each layer having different grain structures/sizes. The interface disposed between the metal oxide layers facilitates oxygen vacancy movement. In many examples, the interface is a misaligned grain interface containing numerous grain boundaries extending parallel to the electrode interfaces, in contrast to the grains in the bulk film extending perpendicular to the electrode interfaces. As a result, oxygen vacancies are trapped and released during switching without significant loss of vacancies.
    Type: Application
    Filed: October 3, 2014
    Publication date: February 26, 2015
    Inventors: Yun Wang, Tony P. Chiang, Vidyut Gopal, Imran Hashim, Dipankar Pramanik
  • Publication number: 20150045428
    Abstract: The present invention relates to ligand-targeted molecules and ligand drug conjugates (LDCs) comprising a ligand connected to a functional group, which is connected to a linker, which in turn is bonded to a drug. The LDCs of the present invention also comprise platinum coordination complex wherein the platinum is connected to the linker through monocarboxylato and O?Pt coordinate bonds. The present invention also relates to methods for preparing these ligand drug conjugates. The present invention further relates to methods for the treatment of tumours using the ligand drug conjugates of the present invention.
    Type: Application
    Filed: January 3, 2013
    Publication date: February 12, 2015
    Inventors: Shiladitya Sengupta, Sazid Hussain, Dipankar Pramanik, Monideepa Roy, Seikh Samad Hossain
  • Publication number: 20150017780
    Abstract: A nonvolatile resistive memory element includes one or more novel oxygen isolation structures that protect the resistive switching material of the memory element from oxygen migration. One such oxygen isolation structure comprises an oxygen barrier layer that isolates the resistive switching material from other portions of the resistive memory device during fabrication and/or operation of the memory device. Another such oxygen isolation structure comprises a sacrificial layer that reacts with unwanted oxygen migrating toward the resistive switching material during fabrication and/or operation of the memory device.
    Type: Application
    Filed: October 2, 2014
    Publication date: January 15, 2015
    Inventors: Yun Wang, Tony P. Chiang, Imran Hashim, Dipankar Pramanik
  • Patent number: 8921181
    Abstract: Methods for forming an electronic device having a fluorine-stabilized semiconductor substrate surface are disclosed. In an exemplary embodiment, a layer of a high-? dielectric material is formed together with a layer containing fluorine on a semiconductor substrate. Subsequent annealing causes the fluorine to migrate to the surface of the semiconductor (for example, silicon, germanium, or silicon-germanium). A thin interlayer of a semiconductor oxide may also be present at the semiconductor surface. The fluorine-containing layer can comprise F-containing WSix formed by ALD from WF6 and SiH4 precursor gases. A precise amount of F can be provided, sufficient to bind to substantially all of the dangling semiconductor atoms at the surface of the semiconductor substrate and sufficient to displace substantially all of the hydrogen atoms present at the surface of the semiconductor substrate.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: December 30, 2014
    Assignee: Intermolecular, Inc.
    Inventor: Dipankar Pramanik
  • Publication number: 20140374240
    Abstract: A nonvolatile memory element is disclosed comprising a first electrode, a near-stoichiometric metal oxide memory layer having bistable resistance, and a second electrode in contact with the near-stoichiometric metal oxide memory layer. At least one electrode is a resistive electrode comprising a sub-stoichiometric transition metal nitride or oxynitride, and has a resistivity between 0.1 and 10? cm. The resistive electrode provides the functionality of an embedded current-limiting resistor and also serves as a source and sink of oxygen vacancies for setting and resetting the resistance state of the metal oxide layer. Novel fabrication methods for the second electrode are also disclosed.
    Type: Application
    Filed: September 8, 2014
    Publication date: December 25, 2014
    Inventors: Hieu Pham, Vidyut Gopal, Imran Hashim, Tim Minvielle, Dipankar Pramanik, Yun Wang, Takeshi Yamaguchi, Hong Sheng Yang
  • Patent number: 8912518
    Abstract: Provided are semiconductor devices, such as resistive random access memory (ReRAM) cells, that include current limiting layers formed from doped metal oxides and/or nitrides. These current limiting layers may have resistivities of at least about 1 Ohm-cm. This resistivity level is maintained even when the layers are subjected to strong electrical fields and/or high temperature annealing. In some embodiments, the breakdown voltage of a current limiting layer may be at least about 8V. Some examples of such current limiting layers include titanium oxide doped with niobium, tin oxide doped with antimony, and zinc oxide doped with aluminum. Dopants and base materials may be deposited as separate sub-layers and then redistributed by annealing or may be co-deposited using reactive sputtering or co-sputtering. The high resistivity of the layers allows scaling down the size of the semiconductor devices including these layer while maintaining their performance.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: December 16, 2014
    Assignee: Intermolecular, Inc.
    Inventors: David Chi, Vidyut Gopal, Minh Huu Le, Minh Anh Nguyen, Dipankar Pramanik, Milind Weling
  • Patent number: 8906736
    Abstract: A nonvolatile memory element is disclosed comprising a first electrode, a near-stoichiometric metal oxide memory layer having bistable resistance, and a second electrode in contact with the near-stoichiometric metal oxide memory layer. At least one electrode is a resistive electrode comprising a sub-stoichiometric transition metal nitride or oxynitride, and has a resistivity between 0.1 and 10 ?cm. The resistive electrode provides the functionality of an embedded current-limiting resistor and also serves as a source and sink of oxygen vacancies for setting and resetting the resistance state of the metal oxide layer. Novel fabrication methods for the second electrode are also disclosed.
    Type: Grant
    Filed: September 8, 2014
    Date of Patent: December 9, 2014
    Assignees: Intermolecular, Inc., Kabushiki Kaisha Toshiba, SanDisk 3D LLC
    Inventors: Hieu Pham, Vidyut Gopal, Imran Hashim, Tim Minvielle, Dipankar Pramanik, Yun Wang, Takeshi Yamaguchi, Hong Sheng Yang
  • Patent number: 8907313
    Abstract: An internal electrical field in a resistive memory element can be formed to reduce the forming voltage. The internal electric field can be formed by incorporating one or more charged layers within the switching dielectric layer of the resistive memory element. The charged layers can include adjacent charge layers to form dipole layers. The charged layers can be formed at or near the interface of the switching dielectric layer with an electrode layer. Further, the charged layer can be oriented with lower valence substitution side towards lower work function electrode, and higher valence substitution side towards higher work function electrode.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: December 9, 2014
    Assignee: Intermolecular, Inc.
    Inventors: Sergey Barabash, Charlene Chen, Dipankar Pramanik
  • Patent number: 8907314
    Abstract: Molybdenum oxide can be used to form switching elements in a resistive memory device. The atomic ratio of oxygen to molybdenum can be between 2 and 3. The molybdenum oxide exists in various Magneli phases, such as Mo13O33, Mo4O11, Mo17O47, Mo8O23, or Mo9O26. An electric field can be established across the switching layers, for example, by applying a set or reset voltage. The electric field can cause movement of the oxygen charges, e.g., O2? ions, changing the composition profile of the switching layers, forming bistable states, including a high resistance state with MoO3 and a low resistance state with MoOx (x<3).
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: December 9, 2014
    Assignee: Intermolecular, Inc.
    Inventors: Sergey Barabash, Tony P. Chiang, Dipankar Pramanik
  • Publication number: 20140353566
    Abstract: A switching element for resistive-switching memory (ReRAM) provides a controllable, consistent filament break-point at an abrupt structural discontinuity between a layer of high-k high-ionicity variable-resistance (VR) material and a layer of low-k low-ionicity VR material. The high-ionicity layer may be crystalline and the low-ionicity layer may be amorphous. The consistent break-point and characteristics of the low-ionicity layer facilitate lower-power operation. The defects (e.g., oxygen or nitrogen vacancies) that constitute the filament originate either in the high-ionicity VR layer or in a source electrode. The electrode nearest to the low-ionicity layer may be intrinsically inert or may be rendered effectively inert. Some electrodes are rendered effectively inert by the creation of the low-ionicity layer over the electrode.
    Type: Application
    Filed: May 28, 2013
    Publication date: December 4, 2014
    Applicants: Intermolecular Inc., SanDisk 3D LLC, Kabushiki Kaisha Toshiba
    Inventors: Yun Wang, Tony P. Chiang, Dipankar Pramanik
  • Patent number: 8895390
    Abstract: Embodiments of the invention generally relate to memory devices and methods for manufacturing such memory devices. In one embodiment, a method for forming a memory device with a textured electrode is provided and includes forming a silicon oxide layer on a lower electrode disposed on a substrate, forming metallic particles on the silicon oxide layer, wherein the metallic particles are separately disposed from each other on the silicon oxide layer. The method further includes etching between the metallic particles while removing a portion of the silicon oxide layer and forming troughs within the lower electrode, removing the metallic particles and remaining silicon oxide layer by a wet etch process while revealing peaks separated by the troughs disposed on the lower electrode, forming a metal oxide film stack within the troughs and over the peaks of the lower electrode, and forming an upper electrode over the metal oxide film stack.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: November 25, 2014
    Assignee: Intermolecular, Inc.
    Inventor: Dipankar Pramanik
  • Patent number: 8883655
    Abstract: Embodiments of the invention generally relate to nonvolatile memory devices, such as a ReRAM cells, and methods for manufacturing such memory devices, which includes optimized, atomic layer deposition (ALD) processes for forming metal oxide film stacks. The metal oxide film stacks contain a metal oxide coupling layer disposed on a metal oxide host layer, each layer having different grain structures/sizes. The interface disposed between the metal oxide layers facilitates oxygen vacancy movement. In many examples, the interface is a misaligned grain interface containing numerous grain boundaries extending parallel to the electrode interfaces, in contrast to the grains in the bulk film extending perpendicular to the electrode interfaces. As a result, oxygen vacancies are trapped and released during switching without significant loss of vacancies.
    Type: Grant
    Filed: May 17, 2013
    Date of Patent: November 11, 2014
    Assignees: Intermoecular, Inc., Kabushiki Kaisha Toshiba, SanDisk 3D LLC
    Inventors: Yun Wang, Tony P. Chiang, Vidyut Gopal, Imran Hashim, Dipankar Pramanik
  • Patent number: 8881073
    Abstract: Roughly described, a method for approximating stress-induced mobility enhancement in a channel region in an integrated circuit layout, including approximating the stress at each of a plurality of sample points in the channel, converting the stress approximation at each of the sample points to a respective mobility enhancement value, and averaging the mobility enhancement values at all the sample points. The method enables integrated circuit stress analysis that takes into account stresses contributed by multiple stress generation mechanisms, stresses having vector components other than along the length of the channel, and stress contributions (including mitigations) due to the presence of other structures in the neighborhood of the channel region under study, other than the nearest STI interfaces. The method also enables stress analysis of large layout regions and even full-chip layouts, without incurring the computation costs of a full TCAD simulation.
    Type: Grant
    Filed: March 25, 2013
    Date of Patent: November 4, 2014
    Assignee: Synopsys, Inc.
    Inventors: Victor Moroz, Dipankar Pramanik
  • Patent number: 8878152
    Abstract: A nonvolatile resistive memory element includes one or more novel oxygen isolation structures that protect the resistive switching material of the memory element from oxygen migration. One such oxygen isolation structure comprises an oxygen barrier layer that isolates the resistive switching material from other portions of the resistive memory device during fabrication and/or operation of the memory device. Another such oxygen isolation structure comprises a sacrificial layer that reacts with unwanted oxygen migrating toward the resistive switching material during fabrication and/or operation of the memory device.
    Type: Grant
    Filed: February 29, 2012
    Date of Patent: November 4, 2014
    Assignees: Intermolecular, Inc., Kabushiki Kaisha Toshiba, SanDisk 3D LLC
    Inventors: Yun Wang, Tony P. Chiang, Imran Hashim, Dipankar Pramanik
  • Publication number: 20140319449
    Abstract: An embodiment of the present invention sets forth an embedded resistive memory cell that includes a first stack of deposited layers, a second stack of deposited layers, a first electrode disposed under a first portion of the first stack, and a second electrode disposed under a second portion of the first stack and extending from under the second portion of the first stack to under the second stack. The second electrode is disposed proximate to the first electrode within the embedded resistive memory cell. The first stack of deposited layers includes a dielectric layer, a high-k dielectric layer disposed above the dielectric layer, and a metal layer disposed above the high-k dielectric layer. The second stack of deposited layers includes a high-k dielectric layer formed simultaneously with the high-k dielectric layer included in the first stack, and a metal layer disposed above the high-k dielectric layer.
    Type: Application
    Filed: July 8, 2014
    Publication date: October 30, 2014
    Inventors: Dipankar Pramanik, Tony P. Chiang, David E Lazovsky
  • Patent number: 8871601
    Abstract: Embodiments of the present invention include diffusion barriers, methods for forming the barriers, and semiconductor devices utilizing the barriers. The diffusion barrier comprises a self-assembled monolayer (SAM) on a semiconductor substrate, where one surface of the SAM is disposed in contact with and covalently bonded to the semiconductor substrate, and one surface of the monolayer is disposed in contact with and covalently bonded to a metal layer. In some embodiments, the barrier comprises an assembly of one or more monomeric subunits of the following structure: Si—(CnHy)-(LM)m where n is from 1 to 20, y is from 2n?2 to 2n, m is 1 to 3, L is a Group VI element, and M is a metal, such as copper. In some embodiments, (CnHy) can be branched, crosslinked, or cyclic.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: October 28, 2014
    Assignee: Intermolecular, Inc.
    Inventors: Xuena Zhang, Mankoo Lee, Dipankar Pramanik
  • Publication number: 20140315369
    Abstract: Provided are semiconductor devices, such as resistive random access memory (ReRAM) cells, that include current limiting layers formed from alloys of transition metals. Some examples of such alloys include chromium containing alloys that may also include nickel, aluminum, and/or silicon. Other examples include tantalum and/or titanium containing alloys that may also include a combination of silicon and carbon or a combination of aluminum and nitrogen. These current limiting layers may have resistivities of at least about 1 Ohm-cm. This resistivity level is maintained even when the layers are subjected to strong electrical fields and/or high temperature processing. In some embodiments, the breakdown voltage of a current limiting layer is at least about 8V. The high resistivity of the layers allows scaling down the size of the semiconductor devices including these layers while maintaining their performance.
    Type: Application
    Filed: June 27, 2014
    Publication date: October 23, 2014
    Inventors: Yun Wang, Tony P. Chiang, Imran Hashim, Tim Minvielle, Dipankar Pramanik, Takeshi Yamaguchi
  • Patent number: 8859328
    Abstract: A nonvolatile memory element is disclosed comprising a first electrode, a near-stoichiometric metal oxide memory layer having bistable resistance, and a second electrode in contact with the near-stoichiometric metal oxide memory layer. At least one electrode is a resistive electrode comprising a sub-stoichiometric transition metal nitride or oxynitride, and has a resistivity between 0.1 and 10 ?cm. The resistive electrode provides the functionality of an embedded current-limiting resistor and also serves as a source and sink of oxygen vacancies for setting and resetting the resistance state of the metal oxide layer. Novel fabrication methods for the second electrode are also disclosed.
    Type: Grant
    Filed: April 16, 2014
    Date of Patent: October 14, 2014
    Assignees: Intermolecular, Inc., Kabushiki Kaisha Toshiba, SanDisk 3D LLC
    Inventors: Hieu Pham, Vidyut Gopal, Imran Hashim, Tim Minvielle, Dipankar Pramanik, Yun Wang, Takeshi Yamaguchi, Hong Sheng Yang
  • Patent number: 8859093
    Abstract: Embodiments of the present invention include low emissivity (low-E) coatings and methods for forming the coatings. The low-E coating comprises a self-assembled monolayer (SAM) on a glass substrate, where one surface of the SAM is disposed in contact with and covalently bonded to the glass substrate, and one surface of the monolayer is disposed in contact with and covalently bonded to a metal layer. In some embodiments, the low-E coating comprises an assembly of one or more monomeric subunits of the following structure: Si—(CnHy)-(LM)m where n is from 1 to 20, y is from 2n?2 to 2n, m is 1 to 3, L is a Group VI element, and M is a metal, such as silver. In some embodiments, (CnHy) can be branched, crosslinked, or cyclic. The coating can further comprise an antireflection coating on the metal layer.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: October 14, 2014
    Assignee: Intermolecular, Inc.
    Inventors: Xuena Zhang, Dipankar Pramanik