Patents by Inventor Tushar P. Merchant

Tushar P. Merchant 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: 9112060
    Abstract: A process and device structure is provided for increasing capacitance density of a capacitor structure. A sandwich capacitor is provided in which a bottom silicon-containing conductor plate is formed with holes or cavities, upon which an oxide layer and a top silicon-containing layer conductor is formed. The holes or cavities provide additional capacitive area, thereby increasing capacitance per footprint area of the capacitor structure. The holes can form, for example, a line structure or a waffle-like structure in the bottom conductor plate. Etching techniques used to form the holes in the bottom conductor plate can also result in side wall tapering of the holes, thereby increasing the surface area of the silicon-containing layer defined by the holes. In addition, depth of holes can be adjusted through timed etching to further adjust capacitive area.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: August 18, 2015
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Tushar P. Merchant, Michael A. Sadd
  • Patent number: 8575588
    Abstract: A method for forming a phase change memory cell (PCM) includes forming a heater for the phase change memory and forming a phase change structrure electrically coupled to the heater. The forming a heater includes siliciding a material including silicon to form a silicide structure, wherein the heater includes at least a portion of the silicide structure. The phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state. The silicide structure produces heat when current flows through the silicide structure for changing the phase state of the phase change structure.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: November 5, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Leo Mathew, Dharmesh Jawarani, Tushar P. Merchant, Ramachandran Muralidhar
  • Patent number: 8563355
    Abstract: A phase change memory (PCM) cell includes a transistor, a PCM structure, and a heater. The transistor has a first current electrode and a second current electrode in a structure, and a channel region having a first portion along a first sidewall of the structure and having a second portion along a second sidewall of the structure. The second sidewall is opposite the first sidewall. The transistor has a control electrode that has a first portion adjacent to the first sidewall and a second portion adjacent to the second sidewall. The PCM structure exhibits first and second resistive values when in first and second phase states, respectively. The heater is on the structure and produces heat when current flows through the heater for changing the phase state of the phase change structure.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: October 22, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Leo Mathew, Tushar P. Merchant, Ramachandran Muralidhar, Rajesh A. Rao
  • Publication number: 20120241909
    Abstract: A process and device structure is provided for increasing capacitance density of a capacitor structure. A sandwich capacitor is provided in which a bottom silicon-containing conductor plate is formed with holes or cavities, upon which an oxide layer and a top silicon-containing layer conductor is formed. The holes or cavities provide additional capacitive area, thereby increasing capacitance per footprint area of the capacitor structure. The holes can form, for example, a line structure or a waffle-like structure in the bottom conductor plate. Etching techniques used to form the holes in the bottom conductor plate can also result in side wall tapering of the holes, thereby increasing the surface area of the silicon-containing layer defined by the holes. In addition, depth of holes can be adjusted through timed etching to further adjust capacitive area.
    Type: Application
    Filed: March 23, 2011
    Publication date: September 27, 2012
    Inventors: Tushar P. Merchant, Michael A. Sadd
  • Patent number: 8168468
    Abstract: A method for making a semiconductor device (10) includes providing an interconnect layer (14) over an underlying layer (12), forming a first insulating layer (16) over the interconnect layer, and forming an opening (18) through the insulating layer to the interconnect layer. A first conductive layer (24) is formed over the interconnect layer and in the opening. This is performed by plating so it is selective. A second conductive layer (28) in the opening is formed by displacement by immersion. This is performed after the first conductive layer has been formed. The result is the second conductive layer is formed by a selective deposition and is effective for providing it with bridging material. A layer of bridgeable material (34) is formed over the second conductive layer and in the opening. A third conductive layer (42) is formed over the bridgeable material. The semiconductor device may be useable as a conductive bridge memory device.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: May 1, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Varughese Mathew, Sam S. Garcia, Tushar P. Merchant
  • Patent number: 8097873
    Abstract: A phase change memory cell has a first electrode, a plurality of pillars, and a second electrode. The plurality of pillars are electrically coupled with the first electrode. Each of the pillars comprises a phase change material portion and a heater material portion. The second electrode is electrically coupled to each of the pillars. In some examples, the pillars have a width less than 20 nanometers.
    Type: Grant
    Filed: September 14, 2010
    Date of Patent: January 17, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ramachandran Muralidhar, Tushar P. Merchant, Rajesh A. Rao
  • Publication number: 20120007031
    Abstract: A method for forming a phase change memory cell (PCM) includes forming a heater for the phase change memory and forming a phase change structrure electrically coupled to the heater. The forming a heater includes siliciding a material including silicon to form a silicide structure, wherein the heater includes at least a portion of the silicide structure. The phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state. The silicide structure produces heat when current flows through the silicide structure for changing the phase state of the phase change structure.
    Type: Application
    Filed: September 21, 2011
    Publication date: January 12, 2012
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: LEO MATHEW, DHARMESH JAWARANI, TUSHAR P. MERCHANT, RAMACHANDRAN MURALIDHAR
  • Patent number: 8043888
    Abstract: A method for forming a phase change memory cell (PCM) includes forming a heater for the phase change memory and forming a phase change structure electrically coupled to the heater. The forming a heater includes siliciding a material including silicon to form a silicide structure, wherein the heater includes at least a portion of the silicide structure. The phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state. The silicide structure produces heat when current flows through the silicide structure for changing the phase state of the phase change structure.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: October 25, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Leo Mathew, Dharmesh Jawarani, Tushar P. Merchant, Ramachandran Muralidhar
  • Patent number: 7932189
    Abstract: An electronic device can include a layer of discontinuous storage elements. A dielectric layer overlying the discontinuous storage elements can be substantially hydrogen-free. A process of forming the electronic device can include forming a layer including silicon over the discontinuous storage elements. In one embodiment, the process includes oxidizing at least substantially all of the layer. In another embodiment, the process includes forming the layer using a substantially hydrogen-free silicon precursor material and oxidizing at least substantially all of the layer.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: April 26, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Tushar P. Merchant, Chun-Li Liu, Ramachandran Muralidhar, Marius K. Orlowski, Rajesh A. Rao, Matthew Stoker
  • Patent number: 7928502
    Abstract: Embodiments of non-volatile semiconductor devices include a substrate having therein a source region and a drain region separated by a channel region extending to a first surface of the substrate, and a multilayered gate structure containing nano-crystals located above the channel region. The gate structure comprises a gate dielectric substantially in contact with the channel region, spaced-apart nano-crystals disposed in the gate dielectric, one or more impurity blocking layers overlying the gate dielectric, and a gate conductor layer overlying the one more impurity blocking layers. The blocking layer nearest the gate conductor can be used to adjust the threshold voltage of the device and/or retard dopant out-diffusion from the gate conductor layer.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: April 19, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Chun-Li Liu, Tushar P. Merchant, Marius K. Orlowski, Matthew W. Stoker
  • Publication number: 20110001113
    Abstract: A phase change memory cell has a first electrode, a plurality of pillars, and a second electrode. The plurality of pillars are electrically coupled with the first electrode. Each of the pillars comprises a phase change material portion and a heater material portion. The second electrode is electrically coupled to each of the pillars. In some examples, the pillars have a width less than 20 nanometers.
    Type: Application
    Filed: September 14, 2010
    Publication date: January 6, 2011
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Ramachandran Muralidhar, Tushar P. Merchant, Rajesh A. Rao
  • Patent number: 7811851
    Abstract: A phase change memory cell has a first electrode, a plurality of pillars, and a second electrode. The plurality of pillars are electrically coupled with the first electrode. Each of the pillars comprises a phase change material portion and a heater material portion. The second electrode is electrically coupled to each of the pillars. In some examples, the pillars have a width less than 20 nanometers.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: October 12, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ramachandran Muralidhar, Tushar P. Merchant, Rajesh A. Rao
  • Publication number: 20100155825
    Abstract: Embodiments of non-volatile semiconductor devices include a substrate having therein a source region and a drain region separated by a channel region extending to a first surface of the substrate, and a multilayered gate structure containing nano-crystals located above the channel region. The gate structure comprises a gate dielectric substantially in contact with the channel region, spaced-apart nano-crystals disposed in the gate dielectric, one or more impurity blocking layers overlying the gate dielectric, and a gate conductor layer overlying the one more impurity blocking layers. The blocking layer nearest the gate conductor can be used to adjust the threshold voltage of the device and/or retard dopant out-diffusion from the gate conductor layer.
    Type: Application
    Filed: March 2, 2010
    Publication date: June 24, 2010
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Chun-Li Liu, Tushar P. Merchant, Marius K. Orlowski, Matthew W. Stoker
  • Patent number: 7719039
    Abstract: A phase change memory cell has a first electrode, a heater, a phase change material, and a second electrode. The heater is over the first electrode, and the heater includes a pillar. The phase change material is around the heater. The second electrode is electrically coupled to the phase change material. In some embodiments, a method includes forming a electrode layer over a substrate, depositing a first layer, providing nanoclusters over the first layer, and etching the first layer. The first layer comprises one of a group consisting of a heater material and a phase change material. The first layer may be etched using the nanocluster defined pattern to form pillars from the first layer.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: May 18, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ramachandran Muralidhar, Tushar P. Merchant, Rajesh A. Rao
  • Patent number: 7704830
    Abstract: A self-aligned split gate bitcell includes first and second regions of charge storage material separated by a gap devoid of charge storage material. Spacers are formed along sidewalls of sacrificial layer extending above and on opposite sides of the bitcell stack, wherein the spacers are separated from one another by at least a gap length. Etching the bitcell stack, selective to the spacers, forms a gap that splits the bitcell stack into first and second gates which together form the split gate bitcell stack. A storage portion of bitcell stack is also etched, wherein etching extends the gap and separates the corresponding layer into first and second separate regions, the extended gap being devoid of charge storage material. Dielectric material is deposited over the gap and etched back to expose a top surface of the sacrificial layer, which is thereafter removed to expose sidewalls of the split gate bitcell stack.
    Type: Grant
    Filed: June 7, 2007
    Date of Patent: April 27, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Rajesh A. Rao, Tushar P. Merchant, Ramachandran Muralidhar, Lakshmanna Vishnubhotla
  • Patent number: 7700438
    Abstract: Methods and apparatus are provided for non-volatile semiconductor devices. The apparatus comprises a substrate having therein a source region and a drain region separated by a channel region extending to a first surface of the substrate, and a multilayered gate structure containing nano-crystals located above the channel region. The gate structure comprises, a gate dielectric substantially in contact with the channel region, spaced-apart nano-crystals disposed in the gate dielectric, one or more impurity blocking layers overlying the gate dielectric and a gate conductor layer overlying the one more impurity blocking layers. The blocking layer nearest the gate conductor can also be used to adjust the threshold voltage of the device and/or retard dopant out-diffusion from the gate conductor layer.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: April 20, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Chun-Li Liu, Tushar P. Merchant, Marius K. Orlowski, Matthew W. Stoker
  • Patent number: 7642163
    Abstract: An electronic device can include a nonvolatile memory cell having DSEs within a dielectric layer. In one aspect, a process of forming the electronic device can include implanting and nucleating a first charge-storage material to form DSEs. The process can also include implanting a second charge-storage material and growing the DSEs such that the DSEs include the first and second charge-storage material. In another aspect, a process of forming the electronic device can include forming a semiconductor layer over a dielectric layer, implanting a charge-storage material, and annealing the dielectric layer. After annealing, substantially none of the charge-storage material remains within a denuded zone within the dielectric layer. In a third aspect, within a dielectric layer, a first set of DSEs can be spaced apart from a second set of DSEs, wherein substantially no DSEs lie between the first set of DSEs and the second set of DSEs.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: January 5, 2010
    Assignee: Freescale Semiconductor, Inc
    Inventors: Rajesh A. Rao, Tushar P. Merchant, Ramachandran Muralidhar, Gowrishankar Chindalore, David Sing, Jane Yater
  • Publication number: 20090218567
    Abstract: A method for making a semiconductor device (10) includes providing an interconnect layer (14) over an underlying layer (12), forming a first insulating layer (16) over the interconnect layer, and forming an opening (18) through the insulating layer to the interconnect layer. A first conductive layer (24) is formed over the interconnect layer and in the opening. This is performed by plating so it is selective. A second conductive layer (28) in the opening is formed by displacement by immersion. This is performed after the first conductive layer has been formed. The result is the second conductive layer is formed by a selective deposition and is effective for providing it with bridging material. A layer of bridgeable material (34) is formed over the second conductive layer and in the opening. A third conductive layer (42) is formed over the bridgeable material. The semiconductor device may be useable as a conductive bridge memory device.
    Type: Application
    Filed: February 29, 2008
    Publication date: September 3, 2009
    Inventors: Varughese Mathew, Sam S. Garcia, Tushar P. Merchant
  • Publication number: 20090184306
    Abstract: A phase change memory (PCM) cell includes a transistor, a PCM structure, and a heater. The transistor has a first current electrode and a second current electrode in a structure, and a channel region having a first portion along a first sidewall of the structure and having a second portion along a second sidewall of the structure. The second sidewall is opposite the first sidewall. The transistor has a control electrode that has a first portion adjacent to the first sidewall and a second portion adjacent to the second sidewall. The PCM structure exhibits first and second resistive values when in first and second phase states, respectively. The heater is on the structure and produces heat when current flows through the heater for changing the phase state of the phase change structure.
    Type: Application
    Filed: January 18, 2008
    Publication date: July 23, 2009
    Inventors: Leo Mathew, Tushar P. Merchant, Ramachandran Muralidhar, Rajesh A. Rao
  • Publication number: 20090184309
    Abstract: A method for forming a phase change memory cell (PCM) includes forming a heater for the phase change memory and forming a phase change structrure electrically coupled to the heater. The forming a heater includes siliciding a material including silicon to form a silicide structure, wherein the heater includes at least a portion of the silicide structure. The phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state. The silicide structure produces heat when current flows through the silicide structure for changing the phase state of the phase change structure.
    Type: Application
    Filed: January 18, 2008
    Publication date: July 23, 2009
    Inventors: Leo Mathew, Dharmesh Jawarani, Tushar P. Merchant, Ramachandran Muralidhar