Including Doping Of Trench Surfaces Patents (Class 438/389)
  • Publication number: 20020102808
    Abstract: A method for forming a dielectric layer with uniform thickness in a trench capacitor comprises providing a substrate structure. A trench device formed in the substrate structure is used as a capacitor and has sidewall and a bottom. Next, the sidewall of the trench device are treated by ion bombardment for forming amorphous structure thereon. Then a dielectric layer, such as an oxide layer, is formed on the sidewall and the bottom of the trench device by CVD or thermal oxidation. To be specific, because of amorphous structure of the sidewall and bottom of the trench device, the dielectric layer can have uniform thickness profile in the trench device.
    Type: Application
    Filed: January 31, 2001
    Publication date: August 1, 2002
    Inventors: Skyland Pu, Yi-Fan Chen
  • Patent number: 6417064
    Abstract: A method of treating the surface of a deep trench is disclosed. After forming a deep trench in a silicon substrate, the silicon substrate near the surfaces of the deep trench is treated to become amorphous. An annealing process is executed to make the amorphous silicon layer recrystallize into its original lattice arrangement, so as to reduce lattice defects in the surface of the deep trench.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: July 9, 2002
    Assignee: Nanya Technology Corporation
    Inventors: Shian-Jyh Lin, Hai-Han Hung
  • Patent number: 6406970
    Abstract: A process for forming a buried strap for memory cells of a semiconductor device having reduced process complexity and improved thickness control of the top trench oxide (TTO) (26). A first oxide layer (16) is deposited over a substrate (11) having trenches formed therein. A first semiconductor material (18) is deposited within the trenches (14). A nitride layer (20) is formed over exposed semiconductor substrate (20) within trenches (14), and a second semiconductor layer (22) is deposited over the nitride layer (20). The top surfaces of the second semiconductor layer (22) are doped to form doped regions (24) and leave undoped second semiconductor layer (22) on the trench (14) sidewalls. The undoped second semiconductor layer (22) is removed from the trench (14) sidewalls, and the doped semiconductor layer (24) within the trench (14) is oxidized to form an oxide region (26), which forms a TTO, within the doped second semiconductor layer (24).
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: June 18, 2002
    Assignee: Infineon Technologies North America Corp.
    Inventors: Stephan Kudelka, Helmut Horst Tews
  • Patent number: 6399435
    Abstract: The present invention provides a method for fabricating a DRAM cell having a trench capacitor. In order to simplify the fabrication method for a DRAM cell, to ensure a high yield and to achieve a high packing density of the DRAM cells, the invention proposes that the storage capacitor (4) of the DRAM cell and the selection transistor (3) be fabricated independently of one another. This saves method steps which, in the prior art, have to be carried out in order to isolate capacitor (9) and gate (16) in the same trench.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: June 4, 2002
    Assignee: Infineon Technologies AG
    Inventor: Jenoe Tihanyi
  • Patent number: 6372573
    Abstract: A process for eliminating roughness on a silicon nitride trench liner is disclosed. A capping film on the top of the trench is formed in a self-aligned manner. This capping film prevents short circuits between a storage node and a passing word-line.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: April 16, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masami Aoki, Hirofumi Inoue, Bruce W. Porth, Max G. Levy, Victor R. Nastasi, Emily E. Fisch, Paul C. Buschner
  • Patent number: 6362040
    Abstract: A method for growing a dielectric layer on a substrate, in accordance with the present invention, includes the steps of providing a substrate having at least two crystallographic planes which experience different dielectric layer growth rates due to the at least two crystallographic planes. A first dielectric layer is grown on the at least two crystallographic planes such that the first dielectric layer has a first thickness on a first crystallographic plane and a second thickness on a second crystallographic plane. The first thickness is thicker than the second thickness for the first dielectric layer. Dopants are implanted through the first dielectric layer. A greater number of dopants are implanted in the substrate through the second thickness than through the first thickness of the first dielectric layer. The first dielectric layer is then removed. A second dielectric layer is grown at a same location as the removed first dielectric layer.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: March 26, 2002
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: Helmut Horst Tews, Brian S. Lee, Ulrike Gruening, Raj Jammy, John Faltermeier
  • Publication number: 20020022316
    Abstract: The method according to the invention enables the roughness of an HSG surface to be substantially transferred to the surface of an electrode. The electrode consequently acquires a microstructured surface, the area of which can be increased by more than 25%, preferably by more than 50% and particularly preferably by more than 100%. An HSG layer is used to locally mask the electrode surface or the sacrificial layer. Subsequent structuring processes, such as for example wet-chemical and/or plasma-assisted etching processes, nitriding or oxidation processes, make it possible—working on the basis of micromasking effects—to significantly roughen the electrode surface and thereby to increase the electrode surface area.
    Type: Application
    Filed: August 7, 2001
    Publication date: February 21, 2002
    Inventors: Martin Gutsche, Alexander Gschwandtner
  • Patent number: 6297088
    Abstract: A method of forming a DRAM cell with a trench capacitor over a semiconductor substrate comprises the following steps. First, an etching step is performed to form a trench structure in the substrate, wherein the trench structure has a bottom and sidewalls, and the sidewalls are adjacent to the bottom. And each the sidewall includes an upper sidewall adjacent to the substrate through a insulating layer and a lower sidewall adjacent to the substrate through a dielectric layer. Then, after the etching steps, a doped area is formed on the bottom and the lower sidewall for serving as the first electrode of the trench capacitor. A first conducting layer is formed on the doped area and the insulating layer above a portion of the upper sidewall to serve as a first capacitor electrode.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: October 2, 2001
    Inventor: Wei-Shang King
  • Publication number: 20010023956
    Abstract: A trench capacitor having an increased surface area. In one embodiment, the trench capacitor is a dual trench capacitor having a first trench and a second trench wherein inner walls of the trenches electrically connect. The invention also includes a single trench capacitor wherein the trench is curved around an axis substantially perpendicular to a substrate surface.
    Type: Application
    Filed: January 23, 2001
    Publication date: September 27, 2001
    Inventors: Christopher N. Collins, Harris C. Jones, James P. Norum, Stefan Schmitz
  • Patent number: 6284593
    Abstract: A process of forming a hybrid memory cell which is scalable to a minimum feature size, F, of about 60 nm at an operating voltage of Vblh of about 1.5 V and substantially free of floating-well effects is provided.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: September 4, 2001
    Assignee: International Business Machines Corporation
    Inventors: Jack A. Mandelman, Ramachandra Divakaruni, Carl J. Radens
  • Patent number: 6281068
    Abstract: An improved method of forming the buried plate regions in deep trench capacitors used in DRAM memory semiconductor circuits in which the polymer used in the deep trench is etched down to the desired depth in a reactive ion etch tool using an O2/CF4 chemistry. Since optical/interferometric etch end-point detection system can be used to monitor the etch back step in its totality, the quantity of the polymer remaining in deep trenches can be very accurately controlled, which in turn will produce a well controlled buried plate region during the out-diffusion step of the arsenic dopant contained in the arsenic doped silicon glass layer.
    Type: Grant
    Filed: April 14, 1999
    Date of Patent: August 28, 2001
    Assignee: International Business Machines Corporation
    Inventors: Philippe Coronel, David Cruau, Francois Leverd, Renzo Maccagnan, Eric Mass
  • Patent number: 6265279
    Abstract: A trench capacitor, in accordance with the present invention, includes a trench formed in a substrate. The trench has a buried plate formed adjacent to a lower portion of the trench. A dielectric collar is formed along vertical sidewalls of the trench. A node diffusion region is formed adjacent to the trench for connecting to a storage node in the trench. A dopant region is formed laterally outward from the trench and adjacent to the collar, and the dopant region includes a profile having a lower portion extending further laterally outward from the trench than an upper portion of the profile wherein operation of a parasitic transistor formed adjacent to the trench between the node diffusion and the buried plate is disrupted by the dopant region. Methods for forming the dopant region are also disclosed and claimed.
    Type: Grant
    Filed: September 24, 1999
    Date of Patent: July 24, 2001
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: Carl Radens, Jack A. Mandelman, Joachim Hoepfner
  • Patent number: 6265278
    Abstract: The preferred embodiment provides an integrated circuit capacitor that achieves a high capacitance by using an inversion layer in the substrate as the plate counter electrode for the capacitor. The inversion layer is created by forming a trench capacitor in a lightly doped substrate. With a sufficient workfunction difference between the storage node material and the isolation band the surface of the lightly doped substrate inverts, with the inversion charge being supplied by the isolation band. This inversion layer serves as the plate counter electrode for the capacitor.
    Type: Grant
    Filed: May 14, 1998
    Date of Patent: July 24, 2001
    Assignees: International Business Machines Corporation, Siemens Aktiengesellschaft
    Inventors: Johann Alsmeier, Jack Allan Mandelman, James Anthony O'Neill, Christopher Parks, Paul Christian Parries
  • Patent number: 6261894
    Abstract: Methods of preparing dual workfunction high-performance support metal oxide semiconductor field effect transistor (MOSFETs)/embedded dynamic random access (EDRAM) arrays are provided. The methods describe herein reduce the number of deep-UV masks used in the forming memory structure, decouple the support and arraying processing steps, provide salicided gates, source/drain regions and bitlines, and provide, in some instances, local interconnects at no additional processing costs. Dual workfunction high-performance support MOSFETs/ EDRAM arrays having a gate conductor guard ring and/or local interconnections are also provided.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: July 17, 2001
    Assignee: International Business Machines Corporation
    Inventors: Jack A. Mandelman, Ramachandra Divakaruni, Carl J. Radens
  • Patent number: 6251722
    Abstract: A method of fabricating a trench capacitor having high capacitance for ULSI technology below the sub-micrometer scale is provided. The method includes: form a trench on a semiconductor substrate. The trench has a bottom portion and at least one sidewall on the semiconductor substrate. Then, form a diffusion layer in the silicon substrate for circumscribing the bottom portion of the trench and a predetermined region of its sidewall. After that, form a first polysilicon layer on the bottom portion of the trench and in a manner that a portion of the first polysilicon layer does not contact with the sidewall. Then, form a first dielectric layer to completely cover the first polysilicon layer and the diffusion layer. Then, form an upper electrode layer on top of the trench to at least completely cover the first dielectric layer. Eventually, the contact area between the diffusion layer and the dielectric layer has been largely increased so as to maintain sufficient capacitance.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: June 26, 2001
    Assignee: Mosel Vitelic Inc.
    Inventors: Houng-chi Wei, Tso-chun Tony Wang
  • Patent number: 6245612
    Abstract: The present invention provides a method for making the bottom electrode of a buried capacitor, which is characterized by protecting the non-bottom electrode region with a LPD oxide layer to prevent the impurities within the doped Si glass remaining in non-bottom electrode region from driving into the substrate during annealing, thus non-desired diffusing region connecting to the bottom electrode will be generated. Consequently, the leakage current existing in conventional buried capacitor will be effectively reduced according to the method of this present invention.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: June 12, 2001
    Assignee: Winbond Electronics Corp.
    Inventors: Wen-Pin Chang, Ming-Lun Chang
  • Patent number: 6232171
    Abstract: A method for fabricating deep-submicron vertically arranged capacitors is disclosed which allows the capacitor to enjoy an enhanced sidewall surface so as to attain a capacitance of 40 pF or more.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: May 15, 2001
    Assignees: ProMOS Technology, Inc., Mosel Vitelic Inc., Siemens AG
    Inventor: Len Mei
  • Patent number: 6211006
    Abstract: The present invention relates to a method of forming a trench-type capacitor. More particularly, the plate areas of the trench-type capacitor are increased according to the present invention.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: April 3, 2001
    Assignee: Nanya Technology Corporation
    Inventors: Hsin-Chuan Tsai, Yi-Nan Chen, Pei-Ing Paul Lee
  • Patent number: 6207494
    Abstract: A method of fabricating a trench cell capacitor can be used in the formation of a DRAM cell. In one embodiment, a trench is formed within a semiconductor substrate. The trench is lined with a dielectric layer, e.g., an ONO layer. After lining the trench, a collar is formed in an upper portion of the trench by forming an oxide layer in the upper portion. A nitride layer on the oxide layer. The trench is then filled with semiconductor material. For example, a semiconductor region can be epitaxially grown to fill the trench.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: March 27, 2001
    Assignee: Infineon Technologies Corporation
    Inventors: Christoff Graimann, Angelika Schulz, Carlos A. Mazure, Christian Dieseldorff
  • Patent number: 6204128
    Abstract: A method for fabricating a semiconductor device includes the steps of: forming a doped layer of a first conductivity type within a surface region of a semiconductor substrate; forming a recess by depositing an insulating film on the semiconductor substrate and then removing at least the insulating film in a region thereof where a gate electrode is to be formed; forming a gate insulating film on the surface of the semiconductor substrate, which is exposed inside the recess; and forming the gate electrode by filling in the recess with a conductive film.
    Type: Grant
    Filed: August 26, 1999
    Date of Patent: March 20, 2001
    Assignee: Matsushita Electronics Corporation
    Inventors: Toshitaka Hibi, Kazuo Hayama
  • Patent number: 6190971
    Abstract: A method and structure for manufacturing an integrated circuit device includes forming a storage device in a substrate, lithographically forming a gate opening in the substrate over the storage device, forming first spacers in the gate opening, forming a strap opening in the substrate using the first spacers to align the strap opening, forming second spacers in the strap opening, forming an isolation opening in the substrate using the second spacers to align the isolation opening, filling the isolation opening with an isolation material, removing the first spacers and a portion of the second spacers to form a step in the gate opening, (wherein the second spacers comprise at least one conductive strap electrically connected to the storage device) forming a first diffusion region in the substrate adjacent the conductive strap, forming a gate insulator layer over the substrate and the step, forming a gate conductor over a portion of the gate insulator layer above the step, forming a second diffusion region in th
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: February 20, 2001
    Assignees: International Business Machines Corporation, Infineon Technologies North America Corp.
    Inventors: Ulrike Gruening, Carl J. Radens
  • Patent number: 6190988
    Abstract: A bottle-shaped trench capacitor with a buried plate is formed in a controlled etch process. The bottle-shape is fabricated by etching deep trenches from a layered substrate, using the layers as a mask, and covering the side walls of the substrate with protective oxide and nitride layers. With the side walls covered, deep trench etching is then resumed, and a lower trench portion, below the protective layers of the side wall are formed. By diffusing a first dopant in the lower portion of the deep trench region, using the side wall protective layers as a mask, an etch stop is established for a wet etch process at the p/n junction established by the first dopant. The width of the lower trench portion is regulated by the time and temperature of the diffusion. Removing the doped material and applying a second dopant to the lower trench portion establishes a continuous buried plate region between trenches. A capacitor is formed by applying an insulating layer to the trench and filling with a conductor.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: February 20, 2001
    Assignee: International Business Machines Corporation
    Inventors: Toshiharu Furukawa, Mark C. Hakey, Steven J. Holmes, David Horak, William H. Ma, James M. Never
  • Patent number: 6159874
    Abstract: A method of manufacturing a capacitor is provided where at least a portion of a silicon surface is amorphized. The amorphized silicon surface is then subjected to an annealing process to form hemispherical silicon grains (HSG) from the amorphized portion of the silicon surface to form at least a portion of a first electrode of the capacitor. A capacitor dielectric is then formed over the hemispherical silicon grains. A second electrode is then formed over the capacitor dielectric.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: December 12, 2000
    Assignee: Infineon Technologies North America Corp.
    Inventors: Helmut Horst Tews, Brian Lee
  • Patent number: 6143616
    Abstract: Methods of forming integrated circuitry lines such as coaxial integrated circuitry interconnect lines, and related integrated circuitry are described. An inner conductive coaxial line component is formed which extends through a substrate. An outer conductive coaxial line component and coaxial dielectric material are formed, with the coaxial dielectric material being formed operably proximate and between the inner and outer conductive coaxial line components. In a preferred implementation, the substrate includes front and back surfaces, and a hole is formed which extends through the substrate and between the front and back surfaces. In one implementation, the outer conductive coaxial line component constitutes doped semiconductive material. In another implementation, such constitutes a layer of metal-comprising material. A layer of dielectric material is formed over and radially inwardly of the outer line component. Conductive material is then formed over and radially inwardly of the dielectric material layer.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: November 7, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Joseph E. Geusic, Kie Y. Ahn, Leonard Forbes
  • Patent number: 6107153
    Abstract: A method for forming a trench capacitor of a dynamic random access memory cell is disclosed. The method includes patterning to etch a semiconductor substrate (10) of a first conductivity to form a trench (18) in the substrate. Ions of the first conductivity are tilt-implanted over the trench, so that sidewalls and a bottom surface of the substrate near the trench are doped with the ions of the first conductivity. Next, first ions of a second conductivity are tilt-implanted over the trench at a first angle, thereby forming a first implanted region (22), followed by tilt-implanting second ions of the second conductivity over the trench at a second angle, thereby forming a second implanted region (24). The first angle is larger than the second angle, and the first implanted region and the second implanted region together form a bottom cell plate of the trench capacitor.
    Type: Grant
    Filed: January 26, 1998
    Date of Patent: August 22, 2000
    Assignee: Texas Instruments -Acer Incorporated
    Inventors: Li-Ping Huang, Shye-Lin Wu
  • Patent number: 6100132
    Abstract: A semiconductor device includes a semiconductor substrate having a trench on a surface thereof and an embedding member embedding the interior of the trench therewith. While the section of the trench when cut by a first plane perpendicular to the direction of the depth of the trench is defined as a first section and the section of the trench when cut by a second plane perpendicular to the direction of the depth of the trench and closer to the bottom of the trench than the first plane is defined as a second section, the area of the first section is smaller than that of the second section and a minimum radius of curvature of the first section is smaller than a minimum radius of curvature of the second section. As a result, it is possible to lessen the concentration of the electric field into the bottom of the trench.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: August 8, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsutomu Sato, Ichiro Mizushima, Yoshitaka Tsunashima, Junichiro Iba
  • Patent number: 6093614
    Abstract: A pair of memory cells for use in a DRAM are formed in a monocrystalline bulk portion of a silicon wafer by first forming a pair of vertical trenches spaced apart by a bulk portion of the wafer. After a dielectric layer is formed over the walls of each trench, the trenches are each filled with polycrystalline silicon. By a pair of recess forming and recess filling steps there is formed at the top of each trench a silicon region that was grown epitaxially with the intermediate bulk portion. Each epitaxial region is made to serve as the body of a separate transistor having its drain in the lower polysilicon fill of a trench, and its source in the monocrystalline bulk intermediate between the two epitaxial regions. The lower polysilicon fill of each trench is also made to serve as the storage node of the capacitor of each cell, with the bulk serving as the other plate of the capacitor.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: July 25, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Ulrike Gruening, Jochen Beintner, Hans-Oliver Joachim
  • Patent number: 6080618
    Abstract: Reduced variations in buried layer across the chip is provided. The reduction in variation is achieved by defining the top surface of the buried layer and then the lower surface of the buried layer. This results in improved control buried strap variations, thereby improving performance of the IC.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: June 27, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Wolfgang Bergner, Johann Alsmeier
  • Patent number: 6077740
    Abstract: A structure and process for forming a contact to a semiconductor substrate on a semiconductor device comprises the step of forming a patterned mask over a semiconductor substrate and over a field oxide region, then etching the semiconductor substrate and the field oxide region to form a trench. The trench comprises a bottom and a first sidewall consisting of silicon and a second sidewall comprising field oxide. The etching step removes a part of a doped region in the substrate. Next, a blanket nitride layer and a blanket oxide layer is formed over the substrate, and a spacer etch is performed on the nitride and oxide layer leaving nitride and oxide over the first and second sidewalls. The trench bottom is oxidized to form a layer of oxide over the bottom of the trench thereby insulating the trench bottom, and the oxide encroaches under the nitride and oxide on the sidewalls to join with the field oxide.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: June 20, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Nanseng Jeng, Steven T. Harshfield, Paul J. Schuele
  • Patent number: 6064085
    Abstract: The present invention discloses a novel multiple fin-shaped capacitor for use in semiconductor memories. The capacitor has a plurality of horizontal fins and a crown shape. The capacitor structure comprises a bottom storage electrode. The bottom storage electrode comprises of a plurality of horizontal fins and a crown shape, wherein said crown shape includes two vertical pillars, and said plurality of horizontal fins extend outside from an external surface of said crown shape. A second dielectric layer is formed on the surface of the bottom storage electrode layer. A top storage electrode layer is formed along the surface of second dielectric layer. By including horizontal fins and vertical pillars, the surface area of the capacitor is significantly increased, resulting in increased capacitance.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: May 16, 2000
    Assignee: Texas Instruments-Acer Incorporated
    Inventor: Shye-Lin Wu
  • Patent number: 6057188
    Abstract: An optimized trench capacitor structure which is useful as a decoupling capacitor or a storage capacitor can be manufactured without added process complexity. As an on-chip decoupling trench capacitor structure, the structure reduces the series resistance to outer and inner plates and results in an acceptable RC delay, while maintaining a high capacitance per unit area. As a storage capacitor with a buried shield, the trench capacitor structure exhibits high immunity to alpha particle and cosmic radiation induced failures. The trench capacitor structure which includes a buried n-well in a silicon substrate. A trench is formed in the substrate and extends through the buried n-well. A dielectric film is formed on an inner surface of the trench, and an inner plate formed as a polysilicon fill within the trench is connected to a surface n+ film formed during definition of peripheral source/drain contacts of the integrated circuit.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: May 2, 2000
    Assignee: International Business Machines Corporation
    Inventors: Badih El-Kareh, Richard Leo Kleinhenz, Stanley Everett Schuster
  • Patent number: 6008103
    Abstract: A method for forming a trench capacitor in a substrate, including a buried plate of the trench capacitor, is disclosed. The method includes forming a trench within the substrate. The trench has a trench interior surface. The method further includes forming an oxide collar within the trench. The oxide collar covers a first portion of the trench interior surface, leaving a second portion of the trench interior surface uncovered with the oxide collar. There is also included doping the second portion of the trench interior surface with a first dopant using a plasma-enhanced doping process. The plasma-enhanced doping process being configured to cause the first dopant to diffuse into the second portion substantially without depositing an additional layer on the trench interior surface. Additionally, there is included driving the first dopant into the substrate using a high temperature process to form the buried plate.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: December 28, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Joachim Hoepfner
  • Patent number: 6004844
    Abstract: A DRAM unit cell is disclosed which comprises a trench capacitor having a signal electrode, a bit line, a planar active word line overlapping the trench capacitor and a planar FET having a main conducting path coupled between the signal electrode of the trench capacitor and the bit line and a gate electrode formed by the active word line.
    Type: Grant
    Filed: July 15, 1996
    Date of Patent: December 21, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventors: Johann Alsmeier, Martin Gall
  • Patent number: 5998254
    Abstract: The method sequence results in a conductive connection between two zones of a first conductivity type. In particular, one of the zones is a source/drain zone of a transistor. Instead of the conventional additional nitride layer, the connection is produced by implanting directly into the third insulation layer, which is present anyway, and by utilizing the fact that the third insulation layer forms the lateral spacers on the gatestack disposed on the region of the second conductivity type.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: December 7, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Lars-Peter Heineck
  • Patent number: 5985729
    Abstract: A silicon oxide layer is formed on the wafer to act as a pad layer. A silicon nitride layer is then formed on the silicon oxide layer to have a thickness approximate 1500-2000 angstroms. At least one trench is then created in the wafer. Then, an ion implantation process is performed with at least one titled angle to dope ions into the surface of the trenches. A LPD-oxide is selectively deposited in the trench. Then, a polysilicon layer is formed on the LPD-oxide and on the surface of the silicon nitride layer. Next, the polysilicon layer is etched to generate polysilicon side-wall spacers. The LPD-oxide is etched using the polysilicon side-wall spacers and the silicon nitride layer as an etching mask. The polysilicon side-wall spacers are then removed. A first conductive layer is formed on the silicon nitride layer, and refilled into the first trenches. The first conductive layer is then etched to at least to expose the LPD-oxide. The LPD-oxide is removed.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: November 16, 1999
    Assignee: Texas Instruments - Acer Incorporated
    Inventor: Shye-Lin Wu
  • Patent number: 5953607
    Abstract: A dynamic random access memory (DRAM) cell is formed with a buried strap which is routed through an isolation trench. This structure frees space in the transfer gate such that the location of the buried strap is not a limiting factor for decreasing the size of DRAM cells.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: September 14, 1999
    Assignee: International Business Machines Corporation
    Inventors: Mark C. Hakey, David V. Horak, Jack A. Mandelman, Wendell P. Noble
  • Patent number: 5942778
    Abstract: A semiconductor device includes (a) a first conductivity type semiconductor substrate having a plurality of trenches formed therein, the trenches defining a plurality of device regions between adjacent trenches, (b) a second conductivity type diffusion layer formed at least around an outer surface of each of the device regions, (c) an insulating film formed on the inner surface of each of the trenches to cover a part of the second conductivity type diffusion layer therewith, (d) a plate electrode formed within each of the trenches, (e) a gate electrode formed above the second conductivity type diffusion layer and (f) a gate insulating film interposed between the gate electrode and the second conductivity type diffusion layer to isolate the gate electrode from the second conductivity type diffusion layer. This semiconductor device eliminates the need for the second conductivity type diffusion layer to serve as a capacitor electrode in contact with a switching transistor.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: August 24, 1999
    Assignee: NEC Corporation
    Inventor: Ryuichi Oikawa
  • Patent number: 5923971
    Abstract: Strap resistance, surface strap shorts and wordline capacitance can be reduced by providing a selectively grown silicon strap which tapers away from spacer nitride and has less contact with spacer nitride. In addition the strap is optionally doped with an arsenic implant which reduces resistance.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: July 13, 1999
    Assignee: International Business Machines Corporation
    Inventors: Herbert L. Ho, Andre R. LeBlanc, Jack A. Mandelman, Radhika Srinivasan
  • Patent number: 5885863
    Abstract: A method for forming a contact is disclosed. A buried impurity region of a second conductivity type is formed in a semiconductor substrate of a first conductivity type. First and second well regions of a first and second conductivity types, respectively, are also formed in the semiconductor substrate. The second well region overlaps the first well region and contacts and surrounds the buried impurity region. A surface impurity concentration of the first well region is greater than a surface impurity concentration of the second well region. A contact to the second well region is formed.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: March 23, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Seiko Yoshida
  • Patent number: 5753558
    Abstract: A method of forming a capacitor includes, a) providing a substrate; b) etching into the substrate to provide a depression in the substrate, the depression having a sidewall which is angled from vertical; c) providing a conformal layer of hemispherical grain polysilicon within the depression and over the angled sidewall, the layer of hemispherical grain polysilicon less than completely filling the depression; and d) ion implanting the hemispherical grain polysilicon layer with a conductivity enhancing impurity. Preferred methods of providing the depression where the substrate comprises SiO.sub.2 include a dry, plasma enhanced, anisotropic spacer etch utilizing reactant gases of CF.sub.4 and CHF.sub.3 provided to the substrate at a volumetric ratio of 1:1, and facet sputter etching.
    Type: Grant
    Filed: April 18, 1997
    Date of Patent: May 19, 1998
    Assignee: Micron Technology, Inc.
    Inventors: Salman Akram, Charles Turner, Alan Laulusa
  • Patent number: 5629226
    Abstract: A trench of a buried plate type DRAM has a bottom portion wider than an opening portion. A silicon oxide film is formed on an upper portion of the side wall of the trench. An N-type impurity diffusion region is formed around the bottom portion of the trench. Impurity diffusion regions of adjacent trenches are integrally connected with each other as one portion. A first polycrystalline silicon layer is formed on the impurity diffusion region in the trench and the silicon oxide film. The polycrystalline silicon layer is coated with a laminated film consisting of a silicon nitride film and a silicon oxide film. The trench is filled with a second polycrystalline silicon layer covering the laminated film. The impurity diffusion region serves as a plate diffusion region of a capacitor, the first polycrystalline silicon layer serves as a plate electrode, the laminated film serves as a capacitor insulating film, and the second polycrystalline silicon layer serves as a storage node electrode.
    Type: Grant
    Filed: July 24, 1995
    Date of Patent: May 13, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Sumito Ohtsuki
  • Patent number: 5270112
    Abstract: The subject invention relates to a hybrid reinforcement material comprising a refractory metal core having a first coating comprising aluminum, oxygen and nitrogen, this coating of the general formula:Al.sub.x O.sub.y N.sub.zwhereinx is up to about 670 atomic % of the coatingy is from about 20 atomic % to about 55 atomic % ofthe coating; andz is from about 5 atomic % to about 45 atomic % of the coating, with the proviso that x+y+z=100, and having a second SiC coating.The subject invention further relates to a high strength, high temperature performance composite containing the hybrid reinforcement specified above.
    Type: Grant
    Filed: December 20, 1989
    Date of Patent: December 14, 1993
    Assignee: Standard Oil Company
    Inventors: D. Lukco, M. A. Tenhover