Patents by Inventor Kunal R. Parekh

Kunal R. Parekh 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: 6232176
    Abstract: The invention includes a number of methods and structures pertaining to integrated circuitry. The invention encompasses a method of forming an integrated circuit comprising: a) forming an insulative material layer over a first node location and a second node location, the insulative material layer having an uppermost surface; and b) forming first and second conductive pedestals extending through the insulative material layer and in electrical connection with the first and second node locations, the conductive pedestals comprising exposed uppermost surfaces which are above the uppermost surface of the insulative material layer.
    Type: Grant
    Filed: March 24, 1999
    Date of Patent: May 15, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, Angela S. Parekh
  • Patent number: 6229174
    Abstract: Disclosed is a method of forming a self-aligned contact to a semiconductor substrate by use of a sacrificial spacer. The sacrificial spacer has the advantage of self aligning metallization to the semiconductive substrate or to a polysilicon plug material without extra photolithography steps as are required in the prior art.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: May 8, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Kunal R. Parekh
  • Patent number: 6228710
    Abstract: The invention encompasses methods of forming DRAM constructions, methods of forming capacitor constructions, DRAM constructions, and capacitor constructions. The invention includes a method in which a) a first layer is formed over a node location; b) a semiconductive material masking layer is formed over the first layer; c) an opening is formed through the semiconductive material masking layer and the first layer to the node location; d) an upwardly open capacitor storage node layer is formed within the opening; e) a storage node is formed from the masking layer and the storage node layer; and f) a capacitor dielectric layer and a capacitor plate are formed over the storage node.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: May 8, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, John K. Zahurak
  • Patent number: 6228738
    Abstract: The invention encompasses DRAM constructions, capacitor constructions, integrated circuitry, and methods of forming DRAM constructions, integrated circuitry and capacitor constructions. The invention encompasses a method of forming a capacitor wherein: a) a first layer is formed; b) a semiconductive material masking layer is formed over the first layer; c) an opening is etched through the masking layer and first layer to a node; d) a storage node layer is formed within the opening and in electrical connection with the masking layer; e) a capacitor storage node is formed from the masking layer and the storage node layer; and f) a capacitor dielectric layer and outer capacitor plate are formed operatively proximate the capacitor storage node.
    Type: Grant
    Filed: November 20, 1998
    Date of Patent: May 8, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, John K. Zahurak
  • Patent number: 6221711
    Abstract: Methods of electrically contacting to conductive plugs, methods of forming contact openings, and methods of forming dynamic random access memory circuitry are described. In one embodiment, a pair of conductive contact plugs are formed to project outwardly relative to a semiconductor wafer. The plugs have respective tops, one of which being covered with different first and second insulating materials. An opening is etched through one of the first and second insulating materials to expose only one of the tops of the pair of plugs. Electrically conductive material is formed within the opening and in electrical connection with the one plug. In a preferred embodiment, two-spaced apart conductive lines are formed over a substrate and conductive plugs are formed between, and on each side of the conductive lines. The conductive plug formed between the conductive lines provides a bit line contact plug having an at least partially exposed top portion.
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: April 24, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Martin Ceredig Roberts, Kunal R. Parekh
  • Patent number: 6214727
    Abstract: The invention encompasses DRAM constructions, capacitor constructions, conductive contacts, integrated circuitry, methods of forming DRAM constructions, and methods of forming capacitor constructions.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: April 10, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Kunal R. Parekh
  • Patent number: 6207523
    Abstract: The invention includes a number of methods and structures pertaining to semiconductor circuit technology, including: methods of forming DRAM memory cell constructions; methods of forming capacitor constructions; DRAM memory cell constructions; capacitor constructions; and monolithic integrated circuitry. The invention includes a method of forming a capacitor comprising the following steps: a) forming a mass of silicon material over a node location, the mass comprising exposed doped silicon and exposed undoped silicon; b) substantially selectively forming rugged polysilicon from the exposed undoped silicon and not from the exposed doped silicon; and c) forming a capacitor dielectric layer and a complementary capacitor plate proximate the rugged polysilicon and doped silicon.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: March 27, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, John K. Zahurak, Phillip G. Wald
  • Patent number: 6191047
    Abstract: The present invention is directed toward building a microelectronic device in which a semiconductor substrate has thereon an etch buffer layer used in a processing method in which the buffer layer will act as an etch uniformity aid. In a method of making the microelectronic device, a semiconductor substrate is covered with an etch buffer layer and with an insulative layer. A first etch is performed by patterning and etching through a mask. The first etch penetrates the insulative layer, forms a cavity therein, and is selective to the buffer layer so as to expose the buffer layer. A second etch is performed that is selective to the insulative layer and the semiconductor substrate, and is not selective to the buffer layer. The buffer layer can be an insulative material of a type other than the material of the insulative layer or the buffer layer can also be of a conductive material.
    Type: Grant
    Filed: June 20, 2000
    Date of Patent: February 20, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Li Li, Zhiqiang Wu, Kunal R. Parekh
  • Patent number: 6180485
    Abstract: The invention includes a number of methods and structures pertaining to semiconductor circuit technology, including: methods of forming DRAM memory cell constructions; methods of forming capacitor constructions; DRAM memory cell constructions; capacitor constructions; and monolithic integrated circuitry. The invention includes a method of forming a capacitor comprising the following steps: a) forming a mass of silicon material over a node location, the mass comprising exposed doped silicon and exposed undoped silicon; b) substantially selectively forming rugged polysilicon from the exposed undoped silicon and not from the exposed doped silicon; and c) forming a capacitor dielectric layer and a complementary capacitor plate proximate the rugged polysilicon and doped silicon.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: January 30, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, John K. Zahurak, Phillip G. Wald
  • Patent number: 6174785
    Abstract: Shallow trench isolation regions in a semiconductor device are formed by utilizing sacrificial spacers such as polysilicon spacers having a rounded shape to form trench isolation areas. The spacer shape is transferred into a semiconductor substrate during an etching process to define the profile of the trench, resulting in a trench with substantially rounded upper and lower corners in the substrate. An oxide filler material is deposited in the trench and over the substrate to form a covering layer. The covering layer is then polished back to form a filled trench region which electrically isolates active areas in the substrate. The polishing step can be performed by a blanket dry etching procedure, or by a combination of chemical/mechanical planarization and wet etching. The rounded shape of the trench improves the electrical characteristics of the trench such that current leakage is decreased, and also provides a more optimized trench profile for filling the trench with the filler material.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: January 16, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, Li Li
  • Patent number: 6165833
    Abstract: A semiconductor processing method includes forming a conductively doped plug of semiconductive material within a first insulative layer. A barrier layer to out diffusion of dopant material from the semiconductive material is formed over the doped plug. Examples include undoped oxide, such as silicon dioxide, and Si.sub.3 N.sub.4. A second insulative layer is formed over the barrier layer. Conductive material is formed through the second insulative layer and into electrical connection with the doped plug. In another implementation, spaced first and second conductively doped regions of semiconductive material are formed. A barrier layer to out diffusion of dopant material from the semiconductive material is formed over at least one of the first and second regions, and preferably over both. Then, a capacitor having a capacitor dielectric layer comprising Ta.sub.2 O.sub.5 is formed over the other of the first and second regions.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: December 26, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, Randhir P. S. Thakur
  • Patent number: 6146961
    Abstract: Capacitors and methods of forming capacitors are described. According to one implementation, a capacitor opening is formed over a substrate node location. Electrically conductive material is subsequently formed within the capacitor opening and makes an electrical connection with the node location. A protuberant insulative structure is formed within the capacitor opening and includes a lateral outer surface at least a portion of which is supported by and extends elevationally below adjacent conductive material. First and second capacitor plates and a dielectric layer therebetween are formed within the capacitor opening and supported by the protuberant structure. In one aspect, the conductive material is formed to occupy less than all of the capacitor opening and to leave a void therewithin, with the protuberant structure substantially, if not completely filling in the void.
    Type: Grant
    Filed: June 23, 1997
    Date of Patent: November 14, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Thomas M. Graettinger, Paul J. Schuele, Pierre C. Fazan, Li Li, Zhiqiang Wu, Kunal R. Parekh, Thomas Arthur Figura
  • Patent number: 6144109
    Abstract: A method and resulting structure for reducing refraction and reflection occurring at the interface between adjacent layers of different materials in a semiconductor device, assembly or laminate during an alignment step in a semiconductor device fabrication process. The method comprises forming a planar-surfaced layer of material, having a first index of refraction, over a substrate of the semiconductor device, assembly or laminate. A corrective layer is formed over the planar-surfaced layer and a second layer, having a second index of refraction, is then formed over the corrective layer. The corrective layer is composed of a material having an intermediate index of refraction between the first index of refraction and the second index of refraction. The method can also be modified to include one or more layers of materials and/or intermediate refraction layers interposed between or above any of the aforementioned adjacent layers.
    Type: Grant
    Filed: February 11, 2000
    Date of Patent: November 7, 2000
    Assignee: Micron Technology, Inc.
    Inventors: William A. Stanton, Phillip G. Wald, Kunal R. Parekh
  • Patent number: 6140172
    Abstract: The invention encompasses DRAM constructions, capacitor constructions, conductive contacts, integrated circuitry, methods of forming DRAM constructions, and methods of forming capacitor constructions.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: October 31, 2000
    Assignee: Micron Technology, Inc.
    Inventor: Kunal R. Parekh
  • Patent number: 6107189
    Abstract: A semiconductor device including a structure having an upper surface and an contact surface formed at the upper surface of the structure. An insulating material is formed over the contact surface and a conductive runner extends over the active area such that a lower surface of the conductive runner is above and separated from the active area. A widened portion is formed in the conductive runner with an opening formed in the widened portion and self-aligned to edges of the widened portion. A conductive pillar is self-aligned to the opening and extends downward through the opening, through the insulating material, to the active area. The conductive runner provides local interconnection that can be routed over device features formed in and on the structure without using an additional metal layer.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: August 22, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Phillip G. Wald, Kunal R. Parekh
  • Patent number: 6107178
    Abstract: An etch of a fuse opening in overlying layers above a laser-blowable semiconductor fuse having a silicon nitride cap and silicon nitride spacers begins with a silicon nitride that is enclosed in a polysilicon conductive layer on a semiconductor wafer. The etch is performed by etching first with an etch process that etches silicon nitride and later with an etch process that is selective to silicon nitride. The later etch process etches the silicon nitride of the cap and spacers little or not at all, allowing a wider variation in etch depths without destroying the fuse. Also, a patch may be provided in the overlying layers above the fuse, and an etch process employed at the level of the patch that is selective to a material of the patch, resulting in an etch stop effect at that level. The etch process is then changed to an etch process that is not selective to a material of the patch, resulting in decreased variation in etch depth over the surface of the wafer.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: August 22, 2000
    Assignee: Micron Technology, Inc.
    Inventors: David S. Becker, Kunal R. Parekh
  • Patent number: 6077790
    Abstract: The present invention is directed toward building a microelectronic device in which a semiconductor substrate has thereon an etch buffer layer used in a processing method in which the buffer layer will act as an etch uniformity aid. In a method of making the microelectronic device, a semiconductor substrate is covered with an etch buffer layer and with an insulative layer. A first etch is performed by patterning and etching through a mask. The first etch penetrates the insulative layer, forms a cavity therein, and is selective to the buffer layer so as to expose the buffer layer. A second etch is performed that is selective to the insulative layer and the semiconductor substrate, and is not selective to the buffer layer. The buffer layer can be an insulative material of a type other than the material of the insulative layer or the buffer layer can also be of a conductive material.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: June 20, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Li Li, Zhiqiang Wu, Kunal R. Parekh
  • Patent number: 6060351
    Abstract: A stacked capacitor memory cell and method for its fabrication including providing a layer of insulation glass over word lines on a silicon semiconductor substrate; self-aligning contact holes at the storage nodes and bit line contact location; providing a blanket layer of polysilicon, then silicide, and then an insulating cap; removing a portion of the insulating cap, silicide and polysilicon to form polysilicon plugs having outward surfaces at an elevation below the surface of the insulating glass, thus forming the bit line, a bit line contact and isolating the storage nodes; and providing a stacked capacitor on top of the bit line and in electrical communication with the storage node contact location through the plugs formed simultaneously with the bit line and bit line contact.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: May 9, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Kunal R. Parekh, John K. Zahurak
  • Patent number: 6049101
    Abstract: Capacitors and methods of forming capacitors are described. According to one implementation, a capacitor opening is formed over a substrate node location. Electrically conductive material is subsequently formed within the capacitor opening and makes an electrical connection with the node location. A protuberant insulative structure is formed within the capacitor opening and includes a lateral outer surface at least a portion of which is supported by and extends elevationally below adjacent conductive material. First and second capacitor plates and a dielectric layer therebetween are formed within the capacitor opening and supported by the protuberant structure. In one aspect, the conductive material is formed to occupy less than all of the capacitor opening and to leave a void therewithin, with the protuberant structure substantially, if not completely filling in the void.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: April 11, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Thomas M. Graettinger, Paul J. Schuele, Pierre C. Fazan, Li Li, Zhiqiang Wu, Kunal R. Parekh, Thomas Arthur Figura
  • Patent number: 6027967
    Abstract: A method of making a capacitor comprising providing a space extending between a pair of gate stacks on a semiconductor substrate, the space exposing a charge conducting region on the semiconductor substrate. A BPSG layer is formed over the pair of gate stacks. A hard mask layer comprising alternating layers of doped polysilicon and undoped polysilicon is formed over the BPSG layer during a single deposition cycle of depositing polysilicon. Portions of the hard mask layer and the BPSG layer are selectively removed to form topographical structures extending above the gate stacks and having a trench therebetween. A spacer etch and a contact etch are performed to expose the charge conducting region. A doped polysilicon spacer is formed on the lateral side of each topographical structure. A second group of alternating layers of doped polysilicon and undoped polysilicon is formed over the topographical structures and within the trench.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: February 22, 2000
    Assignee: Micron Technology Inc.
    Inventors: Kunal R. Parekh, Zhiqiang Wu, Li Li