Including Isolation Structure Patents (Class 438/353)
  • Patent number: 6329279
    Abstract: An outer air spacer structure, applicable to multilevel interconnects technologies, and the method of making the same are disclosed. The outer air spacer is adjacent to a metal line to provide a lower dielectric constant in a metal interconnect structure. The outer air spacer is formed by initially forming a first spacer adjacent to the metal line, followed by forming a second spacer on the first spacer. The first spacer is then removed to form an air gap between the second spacer and the metal line. The air gap is closed to form the outer air spacer by partially sealing the air gap with a portion of passivation layer that is deposited subsequently.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: December 11, 2001
    Assignee: United Microelectronics Corp.
    Inventor: Robin Lee
  • Patent number: 6329260
    Abstract: An integrated circuit has an isolation structure in the form of a double diode moat. The P substrate has P+ buried layers 8601 and 8602 on opposite sides of N+ buried layer 8605. Analog devices are formed behind one diode moat, digital CMOS devices are formed behind the other moat.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: December 11, 2001
    Assignee: Intersil Americas Inc.
    Inventors: Glenn Alan DeJong, Akira Ito, Choong-Sun Rhee, Jeffrey Johnston, Michael D. Church, Kantilal Bacrania
  • Patent number: 6316815
    Abstract: A trench isolation structure characterized by a dielectric stud filling and spanning a trench in a semiconductor substrate is suggested for isolating the integrated circuits fabricated in the semiconductor substrate. The dielectric stud is formed by depositing isolating material in a space defined by the trench and a dielectric layer overlying the semiconductor substrate and being partially removed over an area which spans the trench and extends over the lengthwise edges of the trench.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: November 13, 2001
    Assignee: Vanguard International Semiconductor Corporation
    Inventor: Horng-Huei Tseng
  • Patent number: 6313000
    Abstract: A vertically-isolated bipolar transistor occupying reduced surface area is fabricated by circumscribing an expected active device region within a first narrow trench. The first trench is filled with sacrificial material impermeable to diffusion of conductivity-altering dopant, and then isolation dopant of a conductivity type opposite to that of the substrate is introduced into the trench-circumscribed silicon region. The introduced isolation dopant is then thermally driven into the substrate, with lateral diffusion of isolation dopant physically constrained by the existing first narrow trench. Epitaxial silicon is then formed over the substrate, with polysilicon formed in regions overlying the filled narrow trench. A second, wider trench encompassing the first trench is etched to consume epitaxial silicon, polysilicon, and the sacrificial material. The second trench is then filled with dielectric material.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: November 6, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Publication number: 20010015470
    Abstract: A bipolar transistor is vertically isolated from underlying silicon by an isolation layer of conductivity type opposite that of the collector. This isolation layer lies beneath the heavily doped buried layer portion of the collector, and is formed either by ion implantation prior to epitaxial growth of well regions, or by high energy ion implantation into the substrate prior to formation of the well and the heavily doped buried collector layer. Utilization of trench lateral isolation extending into the semiconductor material beyond the isolation layer permits blanket implant of the isolation layer, obviating the need for an additional masking step.
    Type: Application
    Filed: February 5, 2001
    Publication date: August 23, 2001
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventor: Haydn James Gregory
  • Publication number: 20010006244
    Abstract: A first isolating trench with a predetermined depth is formed in a region where high voltage semiconductor elements are formed on a semiconductor substrate, and a portion of the walls of the first isolating trench is etched corresponding to a depth of a second isolating trench shallower than the first isolating trench to form a third isolating trench. An oxide film filled into the third isolating trench provides isolation between the high voltage semiconductor elements. Then, the second isolating trench is formed in a region where low voltage semiconductor elements are formed, and an oxide film filled into the second isolating trench is used to provide isolation between the low voltage semiconductor elements.
    Type: Application
    Filed: December 11, 2000
    Publication date: July 5, 2001
    Applicant: NEC CORPORATION
    Inventors: Masakuni Shimizu, Eiji Io
  • Patent number: 6235622
    Abstract: Methods of processing semiconductor circuits are disclosed. In one embodiment, a method of processing a semiconductor circuit includes isolating a conductive region of the semiconductor circuit from a substrate region of the semiconductor circuit while forming the semiconductor circuit, and connecting the conductive region to the substrate region after the forming of the semiconductor circuit is completed. In alternate embodiments, the isolating and connecting of the conductive and substrate regions may include de-activating and activating a transistor, respectively.
    Type: Grant
    Filed: August 24, 1999
    Date of Patent: May 22, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Lucien J. Bissey, Bryan C. Carson, Gordon D. Roberts
  • Patent number: 6225181
    Abstract: A bipolar transistor is vertically isolated from underlying silicon by an isolation layer of conductivity type opposite that of the collector. This isolation layer lies beneath the heavily doped buried layer portion of the collector, and is formed either by ion implantation prior to epitaxial growth of well regions, or by high energy ion implantation into the substrate prior to formation of the well and the heavily doped buried collector layer. Utilization of trench lateral isolation extending into the semiconductor material beyond the isolation layer permits blanket implant of the isolation layer, obviating the need for an additional masking step.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: May 1, 2001
    Assignee: National Semiconductor Corp.
    Inventor: Haydn James Gregory
  • Patent number: 6225180
    Abstract: A photoresist pattern is formed on a field oxide film and an element forming region across the field oxide film and the element forming region such that a portion of a surface of the field oxide film and a portion of a surface of a silicon epitaxial layer are continuously exposed. The photoresist pattern is used as a mask to inject boron ions into the silicon epitaxial layer and heat treatment is performed thereon to form an external base containing the relatively significant crystal defect present in the silicon epitaxial layer in the vicinity of the field oxide film. Thus, a semiconductor device can be obtained including a bipolar transistor which provides improved breakdown voltage between the collector and the base and contemplates reduction of current leakage.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: May 1, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hidenori Fujii
  • Publication number: 20010000289
    Abstract: The present invention relates to an integrated circuit including a lateral well isolation bipolar transistor. A first portion of the upper internal periphery of the insulating well is hollowed and filled with polysilicon having the same conductivity type as the transistor base, to form a base contacting region. A second portion of the upper internal periphery of the insulating well is hollowed and filled with polysilicon having the same conductivity type as the transistor emitter, to form an emitter contacting region.
    Type: Application
    Filed: November 30, 2000
    Publication date: April 19, 2001
    Inventor: Yvon Gris
  • Patent number: 6146970
    Abstract: A method for forming a capped shallow trench isolation (CaSTI) structure begin by etching a trench opening (210). The opening (210) is filled with an oxide or like trench fill material (216b) via a deposition and chemical mechanical polish (CMP) step. The plug (216b) is reactive ion etched (RIE) to recess a top of the plug (216b) into the trench opening (210) to form a recessed plug region (216c). A silicon nitride or oxynitride capping layer (218b) is then formed over the recessed plug region (216c) via another deposition and polishing step. The nitride cap layer (218b) protects the underlying region (216c) from erosion due to active area preparation, cleaning, and processing.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: November 14, 2000
    Assignee: Motorola Inc.
    Inventors: Keith E. Witek, Mike Hsiao-Hui Chen, Stephen Shiu-Kong Poon
  • Patent number: 6140160
    Abstract: A method of forming a MOS device using doped and activated n-type and p-type polysilicon layers wherein a first doped and activated polysilicon layer (either n-type and-p-type) is patterned on a substrate. An isolation material layer is formed abutting the first doped and activated polysilicon layer in the corners formed at the junction between the first doped and activated polysilicon layer and the substrate. A second doped and activated polysilicon layer (either n-type or p-type) is applied over the first doped and activated polysilicon layer and the isolation material layer. The second doped and activated polysilicon layer is planarized to the height of the first doped and activated polysilicon layer. The first and second doped and activated polysilicon layers are etched to substantially bifurcate the first and second doped and activated polysilicon layers. Further processing steps known in the art are utilized to complete the MOS device.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: October 31, 2000
    Assignee: Micron Technology, Inc.
    Inventor: Salman Akram
  • Patent number: 6130139
    Abstract: The top surface of a P-type semiconductor substrate is partitioned into an active region to be formed with an element and an isolation region surrounding the active region. The isolation region is composed of trench portions and dummy semiconductor portions. An interlayer insulating film is deposited on the substrate, followed by a wire formed thereon. In each of the semiconductor portions, an impurity diffusion layer is formed simultaneously with the implantation of ions into the element so that a PN junction is formed between the impurity diffusion layer and the silicon substrate. A capacitance component of the wiring-to-substrate capacitance in the region containing the semiconductor portions is obtained by adding in series the capacitance in the impurity diffusion layer to the capacitance in the interlayer insulating film, which is smaller than the capacitance only in the inter layer insulating film.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: October 10, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takaaki Ukeda, Chiaki Kudo, Toshiki Yabu
  • Patent number: 6127716
    Abstract: On an n-type semiconductor substrate 41 doped in high density, a p-type semiconductor layer 2, an n-type semiconductor layer 4 doped in high density, which is a collector, a p-type semiconductor layer 6 doped in high density, which is a base, and the n-type semiconductor layer 7, which is an emitter, are sequentially stacked. To the collector layer, a collector electrode 12 is electrically connected, and to the base layer, a base electrode 11 is electrically connected, and to the emitter layer, an emitter electrode 9 is electrically connected, and thus a bipolar transistor is structured. On the bipolar transistor, an insulated isolation area 55 is formed with an opening therein, whose depth reaches the surface of the substrate, and a substrate electrode 48 is formed thereon. On the bipolar transistor and the insulated isolation area 55, an inter-layer dielectric layer 54 is formed having contact holes formed to upper parts of the emitter electrode 49 and to the substrate electrode 48.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: October 3, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kouhei Morizuka, Masayuki Sugiura
  • Patent number: 6117749
    Abstract: Reduction in the net charge at the interface of a dielectric and a semiconductor material is achieved by placing atomic species in the dielectric near the interface. Preferably, these species are selected from the group of alkaline earth metals. The presence of these atoms results in a redistribution of the electronic density near the interface. The placement of the atoms is effected by ion implantation followed by multiple annealing steps at alternating low and high temperatures.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: September 12, 2000
    Assignee: National Semiconductor Corporation
    Inventors: Sheldon Aronowitz, Kranti Anand, deceased
  • Patent number: 6096618
    Abstract: The invention is a method of fabricating a self-aligned, sub-minimum guard ring for a Schottky diode device wherein the sub-minimum guard ring is positioned at the inside edges of adjacent isolation structures and is self-aligned to the intrinsic base implanted regions. In this particular invention, illustrating the guard ring fabrication technique, an improved Schottky diode is fabricated at minimum groundrules which utilizes a frequency-doubling resist and an appropriate mask to provide the implant mask for a p- or n-type guard ring. This shallow implant near the surface prepares a guard ring that minimizes the electric field at the interface where the deposited metal or silicide joins the STI structure. Additional ion implants with energies greater than and less than the guard ring implantation energy may be deposited to tailor the substrate surface and reduce the parasitic capacitance of the diode.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: August 1, 2000
    Assignee: International Business Machines Corporation
    Inventors: James S. Dunn, Stephen A. St. Onge
  • Patent number: 5972774
    Abstract: A MIS type field effect transistor has a source/drain region overlain by a titanium silicide layer contiguous to an upper silicon nitride layer of a buried isolating structure embedded into a silicon substrate, and a contact hole is formed in an inter-level insulating layer of silicon oxide exposing a part of the upper silicon nitride layer and a part of the titanium silicide layer into the contact hole; while the inter-level insulating layer is being selectively etched so as to form the contact hole, the upper silicon nitride layer serves as an etching stopper, and the contact hole never reaches the silicon substrate beneath the buried isolating structure.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: October 26, 1999
    Assignee: NEC Corporation
    Inventor: Akira Matumoto
  • Patent number: 5888874
    Abstract: A method of forming BiCMOS circuitry includes, i) conducting a first common second conductivity type implant into, a) a first substrate area to comprise a second conductivity type well for a first area first conductivity type FET, and b) a third substrate area to comprise one of a bipolar transistor second conductivity type collector or emitter region; ii) providing field oxide regions and active area regions within first, second and third areas of the substrate; iii) conducting a first common first conductivity type implant into, a) the second substrate area to comprise a first conductivity type channel stop region beneath field oxide in the second area, and b) the third substrate area to comprise the bipolar transistor base; and iv) conducting a second common second conductivity type implant into, a) at least one of the first or the second substrate areas to comprise at least one of a source/drain implant or a graded junction implant for at least one of the first or second conductivity type FETs, and b) the
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: March 30, 1999
    Assignee: Micron Technology, Inc.
    Inventor: Monte Manning
  • Patent number: 5882977
    Abstract: An isolation method in which an isolation ring is formed to isolate a semiconductor device from other semiconductor devices on a common substrate. The method is suitable for isolating bipolar devices from CMOS or other devices formed on the same substrate and for preventing base current from being injected into the substrate. The method starts with a substrate having a buried sub-collector and a first isolation region that surrounds the portion of the surface to contain the semiconductor device. The first isolation region extends only part of the distance from the surface towards the buried sub-collector. Layers of polysilicon and dual-tone resist are applied, and a first mask is used with an opaque area aligned over the portion of the surface to contain the semiconductor device. The edge of the opaque region terminates above the first isolation region. After exposure, the properties of the dual-tone resist allow a narrow sub-minimum width trench to be removed from the resist to define an isolation ring.
    Type: Grant
    Filed: October 3, 1997
    Date of Patent: March 16, 1999
    Assignee: International Business Machines Corporation
    Inventors: James S. Dunn, Stephen A. St. Onge
  • Patent number: 5616509
    Abstract: It is the object of the invention to provide a method for fabricating a semiconductor device, such as a bipolar transistor, with improved characteristics when used in a semiconductor integrated circuit, without increasing the steps in fabricating process. In forming the graft base of the bipolar transistor, oxygen ions with higher energy than that of impurities are injected through the same mask. Thereafter, an insulating film is formed under the graft base region, by activating thermal treatment. Moreover, in a semiconductor integrated circuit of BiCMOS type, insulation films are formed under a source and a drain of a P-type transistor.
    Type: Grant
    Filed: September 28, 1995
    Date of Patent: April 1, 1997
    Assignee: NEC Corporation
    Inventor: Shigeru Hayashi