With Asymmetry In Channel Direction, E.g., High-voltage Lateral Transistor With Channel Containing Layer, E.g., P-base (epo) Patents (Class 257/E21.427)
  • Publication number: 20090001462
    Abstract: A semiconductor structure includes a semiconductor substrate of a first conductivity type; a pre-high-voltage well (pre-HVW) in the semiconductor substrate, wherein the pre-HVW is of a second conductivity type opposite the first conductivity type; a high-voltage well (HVW) over the pre-HVW, wherein the HVW is of the second conductivity type; a field ring in the HVW and occupying a top portion of the HVW, wherein the field ring is of the first conductivity type; an insulation region over and in contact with the field ring and a portion of the HVW; a gate electrode partially over the insulation region; a drain region in the HVW, wherein the drain region is of the second conductivity type; and wherein the HVW horizontally extends further toward the drain region than the pre-HVW; and a source region adjacent to, and on an opposite side of the gate electrode than the drain region.
    Type: Application
    Filed: September 8, 2008
    Publication date: January 1, 2009
    Inventors: Tsung-Yi Huang, Puo-Yu Chiang, Ruey-Hsin Liu, Shun-Liang Hsu, Chyi-Chyuan Huang, Fu-Hsin Chen, Eric Huang
  • Patent number: 7468300
    Abstract: A semiconductor device having a high voltage MOS transistor. The device includes a gate oxide layer disposed between a gate electrode and a substrate on an active area and having relatively thick portions at edges thereof. A fabrication method includes forming on the substrate is a nitride layer having an opening in a high voltage region. An oxide layer is deposited over the substrate and anisotropically etched to remain only on sidewalls of the opening. A first gate oxide layer is formed on the substrate in the opening, and the nitride layer is removed. Then a second gate oxide layer is formed over the substrate such that the second gate oxide layer has a relatively thinner thickness than the first gate oxide layer. Gate electrodes are then formed in the high voltage region and the low voltage region.
    Type: Grant
    Filed: December 30, 2005
    Date of Patent: December 23, 2008
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Yong Keon Choi
  • Patent number: 7465621
    Abstract: A first impurity region of a first type is implanted to have a first surface area on a substrate. A second impurity region of an opposite second type is implanted into a drain region of the transistor to have a second surface area in the first surface area of the first impurity region. A gate oxide is formed after implantation of the second impurity region between a source region and the drain region of the transistor, and the gate oxide is covered with a conductive material. A third impurity region of the opposite second type and a fourth impurity region of the first type are implanted into the source region of the transistor in the first surface area. A fifth impurity region of the opposite second type is implanted into the drain region of the transistor in the second surface area of the second impurity region.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: December 16, 2008
    Assignee: Volterra Semiconductor Corporation
    Inventors: Budong You, Marco A. Zuniga, Andrew J. Burstein
  • Patent number: 7446387
    Abstract: In a HV transistor having a high breakdown voltage and a method of manufacturing the same, a first insulation pattern is formed on a semiconductor substrate by oxidizing a portion of the substrate, and a second insulation pattern is formed such that at least a portion of the first insulation pattern is covered with the second insulation pattern. A gate electrode including a first end portion and a second end portion opposite to the first end portion is formed on the substrate by depositing conductive materials onto the substrate. The first end portion is formed on the first insulation pattern and the second end portion is formed on the second insulation pattern. Source/drain regions are formed at surface portions of the substrate by implanting impurities onto the substrate. Electric field intensity at an edge portion of the gate electrode is reduced, and the HV transistor has a high breakdown voltage.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: November 4, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Mi-Hyun Kang, Hwa-Sook Shin, Mueng-Ryul Lee
  • Patent number: 7446003
    Abstract: A process manufactures power MOS lateral transistors together with CMOS devices on a semiconductor substrate. The process forms a lateral MOS transistor having a gate electrode on the semiconductor region, a source comprising a first highly doped portion aligned with the gate electrode and a drain comprising a lightly doped portion aligned with the gate electrode and a second highly doped portion included in the lightly doped portion. The process forms on the lightly doped portion, a protective layer of a first material; forms on the lateral MOS transistor, a dielectric layer of a second material selectively etchable with respect to the first material; forms, in the dielectric layer first, second, and third openings; and fills the openings with a conductive layer that forms drain and source contacts electrically connected to the first and second highly doped portions, and one electrical shield substantially aligned with the protective layer.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: November 4, 2008
    Assignee: STMicroelectronics S.r.l.
    Inventors: Alessandro Moscatelli, Claudia Raffaglio
  • Publication number: 20080265319
    Abstract: A method of fabricating high-voltage semiconductor devices, the semiconductor devices and a mask for implanting dopants in a semiconductor are described.
    Type: Application
    Filed: April 30, 2007
    Publication date: October 30, 2008
    Inventors: Paulus J.T. Eggenkamp, Priscilla W.M. Boos, Maarten Jacobus Swanenberg, Rob Van Dalen, Anco Heringa, Adrianus Willem Ludikhuize
  • Publication number: 20080185662
    Abstract: A method for forming asymmetric spacer structures for a semiconductor device includes forming a spacer layer over at least a pair of adjacently spaced gate structures disposed over a semiconductor substrate. The gate structures are spaced such that the spacer layer is formed at a first thickness in a region between the gate structures and at a second thickness elsewhere, the second thickness being greater than said first thickness. The spacer layer is etched so as to form asymmetric spacer structures for the pair of adjacently spaced gate structures.
    Type: Application
    Filed: April 3, 2008
    Publication date: August 7, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Haining Yang
  • Publication number: 20080176372
    Abstract: A method of forming a MOSFET is provided. The method comprises forming a relatively thin layer of dielectric on a substrate. Depositing a gate material layer on the relatively thin layer of dielectric. Removing portions of the gate material layer to form a first and second gate material regions of predetermined lateral lengths. Introducing a first conductivity type dopant in the substrate to form a top gate using first edges of the first and second gate material regions as masks, Introducing a second conductivity dopant of high dopant density in the substrate to form a drain region adjacent the surface of the substrate using a second edge of the second gate material region as a mask to form a first edge of the drain region, wherein a spaced distance between the top gate and the drain region is determined by the lateral length of the second gate material region.
    Type: Application
    Filed: March 28, 2008
    Publication date: July 24, 2008
    Applicant: INTERSIL AMERICAS INC.
    Inventor: James D. Beasom
  • Patent number: 7374975
    Abstract: A method of forming a transistor reduces leakage current and hot carrier effects, and therefore improves current performance. The method of forming a transistor includes selectively etching the semiconductor substrate to form a substrate protrusion and expose a buried source/drain implant region. A gate insulating layer covers the substrate protrusion and the first source/drain region. A gate conductor layer is selectively etched to form a gate pattern covering the sidewalls of the substrate protrusion and a portion of the semiconductor substrate adjacent to the sidewalls of the substrate protrusion. A second source/drain region is stacked over the top of the substrate protrusion. Contacts connected to the gate pattern and the first and second source/drain regions.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: May 20, 2008
    Assignee: Dongbu HiTek Co., Ltd.
    Inventor: Jeong-Ho Park
  • Patent number: 7351637
    Abstract: A method of forming a channel in a semiconductor device including forming an opening in a masking layer to expose a portion of an underlying semiconductor layer through the opening is provided. The method further includes disposing a screening layer and implanting a first type of ions in the portion of the underlying semiconductor layer through the screening layer and through the opening in the masking layer. A second type of ions are implanted in the portion of the underlying semiconductor layer through the screening layer and through the opening in the masking layer at an oblique ion implantation angle wherein a lateral spread of second type ions is greater than a lateral spread of first type ions. Semiconductor devices fabricated in accordance to above said method is also provided.
    Type: Grant
    Filed: April 10, 2006
    Date of Patent: April 1, 2008
    Assignee: General Electric Company
    Inventor: Jesse Berkley Tucker
  • Patent number: 7351627
    Abstract: Disclosed herein is a method of manufacturing a semiconductor device via gate-through ion implantation, comprising forming a gate stack on a semiconductor substrate and performing ion implantation for control of the threshold voltage and junction ion implantation for formation of source/drain regions, on the entire surface of the semiconductor substrate having the gate stack formed thereon. In accordance with the present invention, since ion implantation is carried out after formation of the gate stack involving a thermal process, there are no changes in concentrations of implanted dopants due to heat treatment upon formation of the gate stack.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: April 1, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventors: Seung Woo Jin, Min Yong Lee, Kyoung Bong Rouh
  • Patent number: 7344947
    Abstract: Methods fabricate DEMOS devices having varied channel lengths and substantially similar threshold voltages. A threshold voltage is selected for first and second devices. First and second well regions are formed. First and second drain extension regions are formed within the well regions. First and second back gate regions are formed within the well regions according to the selected threshold voltage. First and second gate structures are formed over the first and second well regions having varied channel lengths. A first source region is formed in the first back gate region and a first drain region is formed in the first drain extension region. A second source region is formed in the second back gate region and a second drain region is formed in the drain extension region.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: March 18, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Victor Ivanov, Jozef Czeslaw Mitros
  • Patent number: 7345341
    Abstract: High voltage semiconductor devices and methods for fabricating the same are provided. An exemplary embodiment of a semiconductor device capable of high-voltage operation, comprising a substrate comprising a first well formed therein. A gate stack is formed overlying the substrate, comprising a gate dielectric layer and a gate electrode formed thereon. A channel well and a second well are formed in portions of the first well. A source region is formed in a portion of the channel well. A drain region is formed in a portion of the second well, wherein the gate dielectric layer comprises a relatively thinner portion at one end of the gate stack adjacent to the source region and a relatively thicker portion at one end of the gate stack adjacent to and directly contacts the drain region.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: March 18, 2008
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Yi-Chun Lin, Kuo-Ming Wu, Reuy-Hsin Liu
  • Publication number: 20080042198
    Abstract: Embodiments relate to a Drain Extended Metal-Oxide-Semiconductor (DEMOS) structure in which a drain region may be longer than a source region. In embodiments, the DEMOS may include a gate insulating film and a gate electrode sequentially layered over a semiconductor substrate, a spacer formed at a sidewall of a gate electrode toward the source region, an insulating film pattern formed at a sidewall of the gate electrode toward the drain region to provide a great spacing between the gate electrode and the drain region, the source region formed in the substrate to be in alignment with an edge of the spacer, and the drain region formed in the substrate to be in alignment with an edge of the insulating film pattern. The spacer and the insulating film pattern may be silicon oxide films.
    Type: Application
    Filed: August 16, 2007
    Publication date: February 21, 2008
    Inventor: Chul-Jin Yoon
  • Publication number: 20070296046
    Abstract: In a high withstand voltage transistor of a LOCOS offset drain type having a buried layer, a plurality of stripe-shaped diffusion layers are formed below a diffusion layer ranging from an offset layer to a drain layer and a portion between the drain region and the buried layer is depleted completely; thus, a withstand voltage between the drain region and the buried layer is improved. By the formation of the stripe-shaped diffusion layers, the drain region becomes widened; thus, on-resistance is reduced. Further, the buried layer is made high in concentration so as to sufficiently suppress an operation of a parasitic bipolar transistor.
    Type: Application
    Filed: May 24, 2007
    Publication date: December 27, 2007
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akira Ohdaira, Hisaji Nishimura, Hiroyoshi Ogura
  • Patent number: 7312509
    Abstract: A digital temperature sensing device uses temperature depending characteristic of contact resistance of a MOS transistor and a self-refresh driving device adjusts its self-refresh period depending on temperature using the digital temperature sensing device. The self-refresh driving device includes a first reference voltage generating unit for generating a reference voltage robust to temperature, the first reference voltage generating means being formed with a plurality of MOS transistors, the number of source contacts of the MOS transistors being adjusted such that variation of saturation current through source-drain is compensated for; a second reference voltage generating unit for generating a second reference voltage sensitive to temperature; a level comparator for comparing the first reference voltage with the second reference voltage; and an oscillator for generating a clock signals having differing period depending on the output signal of the level comparator.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: December 25, 2007
    Assignee: Hynix Semiconductor Inc.
    Inventors: Hi-Hyun Han, Jun-Gi Choi
  • Patent number: 7307314
    Abstract: A LDMOS transistor having a gate shield provides reduced drain coupling to the gate shield and source by restricting the thickness of the gate shield and by confining a source contact to the source region without overlap of the gate.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: December 11, 2007
    Assignee: Cree Microwave LLC
    Inventors: Jeff Babcock, Johan Agus Darmawan, John Mason, Ly Diep
  • Patent number: 7282415
    Abstract: A semiconductor device with strain enhancement is formed by providing a semiconductor substrate and an overlying control electrode having a sidewall. An insulating layer is formed adjacent the sidewall of the control electrode. The semiconductor substrate and the control electrode are implanted to form first and second doped current electrode regions, a portion of each of the first and second doped current electrode regions being driven to underlie both the insulating layer and the control electrode in a channel region of the semiconductor device. The first and second doped current electrode regions are removed from the semiconductor substrate except for underneath the control electrode and the insulating layer to respectively form first and second trenches. An insitu doped material containing a different lattice constant relative to the semiconductor substrate is formed within the first and second trenches to function as first and second current electrodes of the semiconductor device.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: October 16, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Da Zhang, Bich-Yen Nguyen, Voon-Yew Thean, Yasuhito Shiho, Veer Dhandapani
  • Patent number: 7208383
    Abstract: An insulated gate field effect transistor having reduced gate-drain overlap and a method for manufacturing the insulated gate field effect transistor. A gate structure is formed on a major surface of a semiconductor substrate. A source extension region and a drain extension region are formed in a semiconductor material using an angled implant. The source extension region extends under the gate structure, whereas the drain extension region is laterally spaced apart from the gate structure. A source region is formed in the semiconductor substrate and a drain region is formed in the semiconductor substrate, where the source and drain regions are laterally spaced apart from the gate structure. A source-side halo region is formed in the semiconductor substrate adjacent the source extension region.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: April 24, 2007
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Chad Weintraub, James F. Buller, Derick Wristers, Jon Cheek
  • Patent number: 7163856
    Abstract: A method of fabricating an LDMOS transistor and a conventional CMOS transistor together on a substrate. A P-body is implanted into a source region of the LDMOS transistor. A gate oxide for the conventional CMOS transistor is formed after implanting the P-body into the source region of the LDMOS transistor. A fixed thermal cycle associated with forming the gate oxide of the conventional CMOS transistor is not substantially affected by the implanting of the P-body into the source region of the LDMOS transistor.
    Type: Grant
    Filed: November 13, 2003
    Date of Patent: January 16, 2007
    Assignee: Volterra Semiconductor Corporation
    Inventors: Budong You, Marco A. Zuniga
  • Patent number: 7145196
    Abstract: A field effect transistor includes a channel region under a gate stack formed on a semiconductor structure. The field effect transistor also includes a drain region formed with a first dopant doping a first side of the channel region, and includes a source region formed with the first dopant doping a second side of the channel region. The drain and source regions are doped asymmetrically such that a first charge carrier profile between the channel and drain regions has a steeper slope than a second charge carrier profile between the channel and source regions.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: December 5, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ki-Jae Hur, Kyung-Seok Oh, Joo-Sung Park, Jung-Hyun Shin
  • Patent number: 7101764
    Abstract: A high-voltage transistor and fabrication process in which the fabrication of the high-voltage transistor can be readily integrated into a conventional CMOS fabrication process. The high-voltage transistor of the invention includes a channel region formed beneath a portion of the gate electrode after the gate electrode has been formed on the surface of a semiconductor substrate. In a preferred embodiment, the channel region is formed by the angled ion implantation of dopant atoms using an edge of the gate electrode as a doping mask. The high-voltage transistor of the invention further includes a drain region that is spaced apart from the channel region by a portion of a well region and by an isolation region residing in the semiconductor substrate. By utilizing the process of the invention to fabricate the high-voltage transistor, the transistor can be integrated into an existing CMOS device with minimal allocation of additional substrate surface area.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: September 5, 2006
    Assignee: SanDisk 3D LLC
    Inventor: Christopher J. Petti