Of Trenches Having Shape Other Than Rectangular Or V Shape, E.g., Rounded Corners, Oblique Or Rounded Trench Walls (epo) Patents (Class 257/E21.549)
  • Patent number: 7396728
    Abstract: A method forms a semiconductor device comprising isolation structures that selectively induce strain into active regions of NMOS and PMOS devices. Form a hard mask layer over a semiconductor body. A resist layer is formed on the hard mask layer that exposes and defines isolation regions. The hard mask layer is patterned and trench regions are formed using the hard mask layer as a mask. An oxide trench liner that induces compressive strain into active regions of the PMOS region is formed within trench regions of the PMOS region. A nitride trench liner that induces tensile strain into active regions of the NMOS region is formed within the NMOS trench regions.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: July 8, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Ajith Varghese, Narendra Singh Mehta, Jonathan McAulay Holt
  • Patent number: 7390717
    Abstract: A fabrication process for a trench type power semiconductor device includes forming inside spacers over a semiconductor surface. Using the spacers as masks, trenches with gates are formed in the semiconductor body. After removing the spacers, source implants are formed in the semiconductor body along the trench edges and are then driven. Insulation caps are then formed over the trenches. Outside spacers are next formed along the sides of the caps. Using these spacers as masks, the semiconductor surface is etched and high conductivity contact regions formed. The outside spacers are then removed and source and drain contacts formed. Alternatively, the source implants are not driven. Rather, prior to outside spacer formation a second source implant is performed. The outside spacers are then formed, portions of the second source implant etched, any remaining source implant driven, and the contact regions formed. The gate electrodes are either recessed below or extend above the semiconductor surface.
    Type: Grant
    Filed: February 9, 2005
    Date of Patent: June 24, 2008
    Assignee: International Rectifier Corporation
    Inventors: Jianjun Cao, Paul Harvey, David Kent, Robert Montgomery, Kyle Spring
  • Patent number: 7391096
    Abstract: An STI structure and fabricating method thereof are disclosed. The STI fabricating method comprises forming a pad oxide layer and a first nitride layer on a substrate. A trench is formed by etching the first nitride layer, the pad oxide layer and the substrate. An oxide and a second nitride layer are deposited on the surface of the substrate including the trench. A spacer is formed on the lateral walls of the trench by etching the second nitride layer. A buried oxide is grown in the substrate underneath the trench by performing thermal oxidation on the substrate. The trench is then filled by depositing an insulating layer after removing the spacer and performing a planarization process. The STI fabricating method can reduce substantially a total parasitic capacitance. Therefore, gate RC delay is reduced and the operating speed of a transistor increases.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: June 24, 2008
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Jin Hyo Jung
  • Patent number: 7375004
    Abstract: A method of forming and resulting isolation region, which allows for densification of an oxide layer in the isolation region. One exemplary embodiment of the method includes the steps of forming a first trench, forming an oxide layer on the bottom and sidewalls of the trench, forming nitride spacers on the lined trench, and thereafter etching the silicon beneath the first trench to form a second trench area. An oxide layer is then deposited to fill the second trench. Densificiation of the isolation region is possible because the silicon is covered with nitride, and therefore will not be oxidized. Light etches are then performed to etch the oxide and nitride spacer area in the first trench region. A conventional oxide fill process can then be implemented to complete the isolation region.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: May 20, 2008
    Assignee: Micron Technology, Inc.
    Inventors: Sukesh Sandhu, Gurtej Sandhu
  • Patent number: 7371655
    Abstract: A low-power CMOS device can be fabricated by forming a shallow trench on a silicon substrate using a gate mask and negative photoresist. This enables an extremely low profile for a junction after completion of lightly doped drain and source/drain implantations. The method includes forming a shallow trench in a silicon substrate.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: May 13, 2008
    Assignee: Dongbu Electronics Co., Ltd
    Inventor: Eun Jong Shin
  • Patent number: 7358588
    Abstract: A trench isolation type semiconductor device in which a recess is prevented from being formed in a field region and a method of fabricating the same are provided. The trench isolation type semiconductor device includes a semiconductor substrate defined by an active region and a field region, a trench formed in the field region, an oxide layer conformally formed along the inside of the trench, a liner layer conformally formed along the oxide layer, a field insulating layer formed inside the trench including the oxide layer and the liner layer, and a field protection layer formed on the field insulating layer so that a step difference does not occur on the semiconductor substrate.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: April 15, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ki-seog Youn, Jong-hyon Ahn, Deok-hyung Lee, Sung-gun Kang, Kong-soo Cheong
  • Publication number: 20080057672
    Abstract: A shallow trench isolation structure having a negative taper angle and a method for forming same. A silicon nitride layer formed over a semiconductor substrate is etched according to a plasma etch process to form a first opening therein having sidewalls that present a negative taper angle. The substrate is etched to form a trench therein underlying the first opening. Silicon dioxide fills both the opening and the trench to form the shallow trench isolation structure, with the silicon dioxide in the opening exhibiting a negative taper angle to avoid formation of conductive stringers during subsequent process steps.
    Type: Application
    Filed: October 29, 2007
    Publication date: March 6, 2008
    Applicant: Agere Systems Inc.
    Inventors: Nace Rossi, Ranbir Singh, Arun Nanda
  • Patent number: 7339252
    Abstract: A method of manufacturing a semiconductor device includes providing a semiconductor substrate having first and second main surfaces opposite to each other. The method also includes providing in the semiconductor substrate one or more trenches, first mesas and second mesas. The method also includes oxidizing sidewalls and bottoms of each trench; depositing a doped oxide into each trench and on the tops of the first and second mesas; and thermally oxidizing the semiconductor substrate at a temperature sufficient enough to cause the deposited oxide to flow so that the silicon in each of the first mesas is completely converted to silicon dioxide while the silicon in each of the second mesas is only partially converted to silicon dioxide and so that each of the trenches is filled with oxide.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: March 4, 2008
    Assignee: Third Dimension (3D) Semiconductor, Inc.
    Inventor: Richard A. Blanchard
  • Publication number: 20080003739
    Abstract: A method for forming an isolation structure of a flash memory device includes providing a substrate structure where a tunnel insulating layer, a conductive layer, and a padding layer are formed, etching the padding layer, the conductive layer, the tunnel insulating layer and the substrate to form a trench, forming a first insulating layer over the substrate structure and filling in a portion of the trench, forming a second insulating layer over the substrate structure, forming a third insulating layer over the substrate structure to fill the trench, polishing the first, second and third insulating layers using the padding layer as a polish stop layer, removing the padding layer and simultaneously recessing the third insulating layer to protrude the first and second insulating layers, and etching the first and second insulating layers while recessing the third insulating layer to form a protective layer on sidewalls of the conductive layer.
    Type: Application
    Filed: December 28, 2006
    Publication date: January 3, 2008
    Inventors: Seung-Cheol Lee, Gyu-An Jin
  • Patent number: 7314809
    Abstract: A method for forming a shallow trench isolation (STI) structure with reduced stress is described. An amorphous silicon layer is deposited on a trench surface of a shallow trench isolation structure, and the amorphous silicon is then oxidized by thermal oxidation to form a liner oxide. The thickness of the liner oxide is uniform to reduce stress caused by a liner oxide having non-uniform thickness in the prior art, and the leakage risk between the semiconductor devices can thus be prevented.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: January 1, 2008
    Assignee: ProMOS Technologies Inc.
    Inventor: Wen-Pin Chiu
  • Patent number: 7279393
    Abstract: The present invention provides a trench isolation structure, a method for manufacturing a trench isolation structure, and a method for manufacturing an integrated circuit including the trench isolation structure. In one aspect, the method includes forming a hardmask over a substrate, etching a trench in the substrate through the hardmask, forming a liner in the trench, depositing an interfacial layer over the liner within the trench and over the hardmask and filling the trench with a dielectric material.
    Type: Grant
    Filed: September 29, 2004
    Date of Patent: October 9, 2007
    Assignee: Agere Systems Inc.
    Inventors: Arun Nanda, Nace Rossi, Ranbir Singh
  • Publication number: 20070228455
    Abstract: In the memory array area of a semiconductor substrate, memory cells of a NAND flash memory are arranged in a matrix in the row direction and the column direction. A plurality of memory cells arranged in the row direction are mutually isolated by device isolation trenches having a thin strip planar shape extending in the column direction. The diameter of the device isolation trenches in the row direction at the bottom portion thereof is larger than that near the surface.
    Type: Application
    Filed: January 3, 2007
    Publication date: October 4, 2007
    Inventors: Yoshitaka Sasago, Tomoyuki Ishii, Toshiyuki Mine
  • Patent number: 7273792
    Abstract: A semiconductor device including a semiconductor substrate, a device isolation region formed by filling a trench in the semiconductor substrate with dielectric material and defining device regions in the semiconductor substrate. The trench has a rounded upper edge, and a dummy thin layer formed on the rounded upper edge.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: September 25, 2007
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Yong Keon Choi
  • Publication number: 20070114633
    Abstract: An integrated circuit device has a substrate with first and second portions. One or more first active regions are formed in the first portion of the substrate. Each of the one or more first active regions has rounded corners. One or more first circuit elements are formed on the one or more first active regions after the corners of the one or more first active regions have been rounded. One or more second active regions are formed in the second portion of the substrate. One or more second circuit elements are formed on the one or more second active regions.
    Type: Application
    Filed: January 12, 2007
    Publication date: May 24, 2007
    Inventors: Sukesh Sandhu, Kevin Torek
  • Patent number: 7205207
    Abstract: A semiconductor device and method of manufacture provide an n-channel field effect transistor (nFET) having a shallow trench isolation with overhangs that overhang Si—SiO2 interfaces in a direction parallel to the direction of current flow and in a direction transverse to current flow. The device and method also provide a p-channel field effect transistor (pFET) having a shallow trench isolation with an overhang that overhangs Si—SiO2 interfaces in a direction transverse to current flow. However, the shallow trench isolation for the pFET is devoid of overhangs, in the direction parallel to the direction of current flow.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: April 17, 2007
    Assignee: International Business Machines Corporation
    Inventors: Bruce B. Doris, Oleg G. Gluschenkov
  • Patent number: 7163869
    Abstract: A STI (shallow trench isolation) structure is formed with a liner layer that is converted from an initial material to a subsequent material. For example, the liner layer is initially comprised of nitride during wet etch-back of a dielectric fill material comprised of oxide to protect an oxide layer on a semiconductor substrate. Thereafter, an exposed portion of the liner layer is converted into the subsequent material of oxide to protect the dielectric fill material within the STI opening during etching away of masking layers to prevent formation of dents in the STI structure.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: January 16, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Shin-Hye Kim, Min Kim, Seung-Jae Lee
  • Patent number: 7160789
    Abstract: A shallow trench isolation (STI) structure and a method of forming the STI structure. The STI structure defines an active region formed with a recess channel transistor. The STI structure includes a STI trench has a laterally curved rounding portion on the bottom of the recess channel trench. In order to form the STI trench with the rounding portion, a semiconductor substrate is selectively and anisotropically dry etched to form the trench. Then, the semiconductor substrate is isotropically etched around the bottom height of the recess channel trench to form the rounding portion, and then further anisotropically dry etched, thereby forming the STI trench. After an insulating layer that fill the STI trench is formed on the resultant structure, an upper surface of the resultant structure is planarized to expose a surface of the semiconductor substrate.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: January 9, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jong-Chul Park
  • Publication number: 20060286739
    Abstract: A shallow trench isolation structure having a negative taper angle. A graded doped sacrificial layer is formed over a semiconductor substrate and etched to form a first trench therein having trench sidewalls that present a negative taper angle. The substrate is also etched to form a second trench therein overlying the first trench. Silicon dioxide fills both the first and the second trenches to form the shallow trench isolation structure, with the silicon dioxide in the first trench exhibiting a negative taper angle to avoid formation of polysilicon stringers during a gate polysilicon deposition.
    Type: Application
    Filed: June 15, 2005
    Publication date: December 21, 2006
    Inventors: Nace Rossi, Ranbir Singh, Arun Nanda
  • Patent number: 7148120
    Abstract: A method for forming a shallow trench isolation (STI) structure with improved electrical isolation performance including providing a semiconductor substrate including an overlying silicon oxide layer on the semiconductor substrate and a hardmask layer on the silicon oxide layer; dry etching in a first etching process to form a patterned hardmask opening for etching an STI opening; dry etching in a second etching process the semiconductor substrate to form an upper portion of an STI opening to form a polymer layer along sidewall portions of the STI opening; and, dry etching in a third etching process the STI opening to form rounded bottom corners and rounded top corners.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: December 12, 2006
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Po-Jen Chen, Jen-Hsiang Leu, Yan-Chang Liu
  • Patent number: 7141486
    Abstract: A shallow trench isolation structure having a negative taper angle. A graded doped sacrificial layer is formed over a semiconductor substrate and etched to form a first trench therein having trench sidewalls that present a negative taper angle. The substrate is also etched to form a second trench therein overlying the first trench. Silicon dioxide fills both the first and the second trenches to form the shallow trench isolation structure, with the silicon dioxide in the first trench exhibiting a negative taper angle to avoid formation of polysilicon stringers during a gate polysilicon deposition.
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: November 28, 2006
    Assignee: Agere Systems Inc.
    Inventors: Nace Rossi, Ranbir Singh, Arun K. Nanda
  • Patent number: 7061075
    Abstract: A film stack for forming shallow trench isolation among transistors and other devices on a semiconductor substrate is provided, including a plurality of light absorbing layers alternating between a layer of SiON and a layer of SiO2 and having a combined extinction coefficient >0.5. As reflected light interacts with the light absorbing layers, a substantial amount of light is absorbed therein thereby blocking such reflected light from negatively interfering with patterning of the photoresist during photo-lithography. Following patterning of the photoresist, isolation trenches may be formed in the semiconductor substrate by etching through the light absorbing layers and into the semiconductor substrate in accordance with the pattern formed on the photoresist.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: June 13, 2006
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Carl P. Babcock, Jayendra D. Bhakta