With Thick Insulator To Reduce Gate Capacitance In Non-channel Areas (e.g., Thick Oxide Over Source Or Drain Region) Patents (Class 257/333)
  • Patent number: 7557409
    Abstract: In a trench MOSFET, the lower portion of the trench contains a buried source electrode, which is insulated from the epitaxial layer and semiconductor substrate but in electrical contact with the source region. When the MOSFET is in an “off” condition, the bias of the buried source electrode causes the “drift” region of the mesa to become depleted, enhancing the ability of the MOSFET to block current. The doping concentration of the drift region can therefore be increased, reducing the on-resistance of the MOSFET. The buried source electrode also reduces the gate-to-drain capacitance of the MOSFET, improving the ability of the MOSFET to operate at high frequencies. The substrate may advantageously include a plurality of annular trenches separated by annular mesas and a gate metal layer that extends outward from a central region in a plurality of gate metal legs separated by source metal regions.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: July 7, 2009
    Assignee: Siliconix Incorporated
    Inventors: Deva N. Pattanayak, Yuming Bai, Kyle Terrill, Christiana Yue, Robert Xu, Kam Hong Lui, Kuo-In Chen, Sharon Shi
  • Patent number: 7541642
    Abstract: A semiconductor device comprises a semiconductor substrate having a gate trench formed therein. A gate electrode is formed on a gate insulator in the gate trench. The gate electrode has ends close to the bottom of the gate trench, which are separated in a direction perpendicular to both sides of the gate trench, and portions except the separated ends, at least part of which is made higher in conductivity than other parts.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: June 2, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keiko Kawamura, Masanobu Tsuchitani
  • Patent number: 7541641
    Abstract: Disclosed are a gate structure in a trench region of a semiconductor device and method for manufacturing the same. The semiconductor device includes a pair of drift regions formed in a semiconductor substrate; a trench region formed between the pair of drift regions; an oxide layer spacer on sidewalls of the trench region; a gate formed in the trench region; and a source and a drain formed in the pair of the drift regions, respectively.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: June 2, 2009
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Kwang Young Ko
  • Publication number: 20090114983
    Abstract: A power transistor capable of decreasing capacitance between a gate and a drain includes a backside mental layer, a substrate formed on the backside mental layer, a semiconductor layer formed on the substrate, and a frontside mental layer formed on the semiconductor layer. The semiconductor layer comprises a first trench structure comprising a gate oxide layer, a second trench structure comprising a p-well junction formed around a second trench, a p-body region formed outside the first trench structure and the second trench structure, a first n+ source region formed on the p-body region and beside a sidewall of the first trench structure, a second n+ source region formed on the p-body region and between another sidewall of the first trench structure and the second trench structure, and a dielectric layer formed on the first trench structure, the first n+ source region, and the second n+ source region.
    Type: Application
    Filed: June 20, 2008
    Publication date: May 7, 2009
    Inventors: Wei-Chieh Lin, Jen-Hao Yeh, Ming-Jang Lin
  • Patent number: 7518186
    Abstract: A gate electrode is buried in a trench passing through a second conductivity type first body region formed on a first conductivity type drain region so as to form a recessed portion at the upper part of the trench. An insulating film is formed on the gate electrode so as to occupy the recessed portion partway. A first conductivity type source region is formed in at least a region of the upper part of the first body region which serves as at least the wall part of the trench. A second conductivity type second body region is formed in the other region of the upper part thereof so as to be adjacent to the source region in the direction that the trench extends. A second conductivity type third body region is formed in the respective upper parts of the source region and the second body region.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: April 14, 2009
    Assignee: Panasonic Corporation
    Inventor: Shuji Mizokuchi
  • Publication number: 20090072306
    Abstract: A semiconductor device according to the present invention includes a semiconductor layer. A first conductivity type region is formed on a base layer portion of the semiconductor layer. A body region of a second conductivity type is formed on the semiconductor layer to be in contact with the first conductivity type region. A trench in which a gate electrode is embedded through a gate insulating film is formed on the semiconductor layer. The trench penetrates through the body region, so that a deepest portion thereof reaches the first conductivity type region. A source region of the first conductivity type is formed on a surface layer portion of the semiconductor layer around the trench. The gate insulating film includes a thick-film portion having a relatively large thickness on a bottom surface of the trench.
    Type: Application
    Filed: September 2, 2008
    Publication date: March 19, 2009
    Applicant: ROHM CO., LTD.
    Inventor: Naoki Izumi
  • Patent number: 7504691
    Abstract: Devices, methods, and processes that improve immunity to transient voltages and reduce parasitic impedances. Immunity to unclamped inductive switching events is improved. For example, a trench-gated power MOSFET device having a SiGe source is provided, where the SiGe source reduces parasitic npn transistor gain by reducing hole current in the body or well region, thereby decreasing the likelihood of a latch-up condition. A trench-gated power MOSFET device having a SiGe body or well region is also provided. A SiGe body reduces hole current when the body diode is turned on, thereby reducing reverse recovery power losses. Other device characteristics are also improved. For example, parasitic gate impedance can reduced through the use of a poly SiGe gate. Also, channel resistance can be reduced through the use of a SiGe layer near the device's gate and a thick oxide region can be formed under the trench gate to reduce gate-to-drain capacitance.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: March 17, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Chanho Park, Qi Wang
  • Patent number: 7492004
    Abstract: According to some embodiments of the invention, transistors have channel regions between channel-portion holes. Methods of forming the same include at least two channel-portion holes disposed in a semiconductor substrate. Line patterns are formed in parallel to be spaced apart from each other on a main surface of the semiconductor substrate to fill the channel-portion holes. A channel region is disposed in the semiconductor substrate below the line patterns. At this time, the channel region is formed between the channel-portion holes and also covers lower portions of the channel-portion holes. Driving current capability and refresh characteristics of DRAMs utilizing the inventive transistors are improved.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: February 17, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-Woo Lee, Tae-Young Chung, Yong-Sung Kim
  • Patent number: 7485921
    Abstract: This semiconductor device comprises a first semiconductor layer of a first conductivity type, an epitaxial layer of a first conductivity type formed in the surface on the first semiconductor layer, and a base layer of a second conductivity type formed on the surface of the epitaxial layer. Column layers of a second conductivity type are repeatedly formed in the epitaxial layer under the base layer at a certain interval. Trenches are formed so as to penetrate the base layer to reach the epitaxial layer; and gate electrodes are formed in the trenches via a gate insulation film. A termination layer of a second conductivity type is formed on the epitaxial layer at an end region at the perimeter of the base layer. The termination layer is formed to have a junction depth larger than that of the base layer.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: February 3, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kawaguchi, Yoshihiro Yamaguchi, Syotaro Ono, Miwako Akiyama
  • Patent number: 7485911
    Abstract: A semiconductor device having a decoupling capacitor and a method of fabricating the same are provided. The semiconductor device includes a semiconductor substrate having a cell region, a first peripheral circuit region, and a second peripheral circuit region. At least one channel trench is disposed in the cell region of the semiconductor substrate. At least one first capacitor trench is disposed in the first peripheral circuit region of the semiconductor substrate, and at least one second capacitor trench is disposed in the second peripheral circuit region of the semiconductor substrate. A gate electrode is disposed in the cell region of the semiconductor substrate and fills the channel trench. A first upper electrode is disposed in the first peripheral circuit region of the semiconductor substrate and fills at least the first capacitor trench. A second upper electrode is disposed in the second peripheral circuit region of the semiconductor substrate and fills at least the second capacitor trench.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: February 3, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyun-Ki Kim, Jung-Hwa Lee, Ji-Young Kim
  • Patent number: 7476920
    Abstract: An access transistor arrangement is provided for a 6F2 stacked capacitor DRAM memory cell layout with shared bit line contacts. The access transistors are arranged in pairs along semiconductor lines. The two transistors of each pair of transistors are arranged laterally reversed opposing the respective common bit line section. Each pair of access transistors is separated from the adjacent pair of access transistors by an isolation transistor which is permanently turned off. The access transistors and the isolation transistors are formed as identical recessed channel transistors with elongated channel and enhanced isolation properties. The same dopant concentration may be provided for both junctions of the access transistors. As identical devices are provided both as access transistor and as isolation transistors, the complexity of lithographic patterning processes is reduced.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: January 13, 2009
    Assignee: Infineon Technologies AG
    Inventor: Till Schloesser
  • Patent number: 7465989
    Abstract: A high withstand voltage transistor includes: a gate electrode provided in a trench formed on a semiconductor substrate; a source and a drain which are respectively formed on a side of the gate electrode and another side of the gate electrode, and which are a predetermined distance away from the gate electrode; first electric field relaxation layers one of which is formed on a wall of the trench on the side of the source and another one of which is formed on a wall of the trench on the side of the drain; and second electric field relaxation layers one of which is formed between the source and the gate electrode, and another one of which is formed between the drain and the gate electrode.
    Type: Grant
    Filed: September 24, 2007
    Date of Patent: December 16, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Keiji Hayashi
  • Patent number: 7465622
    Abstract: A method for fabricating a vertical channel transistor device is provided. An opening is formed in a dielectric stack comprised of a pad nitride layer and a pad oxide layer. A plurality of epitaxial silicon growth and dry etching processes are carried out to form drain, vertical channel and source in the opening. Subsequently, sidewall gate dielectric and sidewall gate electrode are formed on the vertical channel. The present invention is suited for dynamic random access memory (DRAM) devices, particularly suited for very high-density trench-capacitor DRAM devices.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: December 16, 2008
    Assignee: Nanya Technology Corp.
    Inventor: Shian-Jyh Lin
  • Patent number: 7465987
    Abstract: A trench transistor structure having a field electrode arrangement formed in trenches is disclosed. In one embodiment, the field electrode arrangement is conductively connected to subvoltage taps of a voltage divider for the purpose of stabilizing the potentials on a longer time scale than dynamic charge reversal processes.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: December 16, 2008
    Assignee: Infineon Technologies Austria AG
    Inventors: Joachim Krumrey, Franz Hirler, Walter Rieger
  • Patent number: 7453119
    Abstract: This invention discloses a semiconductor power device that includes a plurality of power transistor cells surrounded by a trench opened in a semiconductor substrate. At least one active cell further includes a trenched source contact opened between the trenches wherein the trenched source contact opened through a source region into a body region for electrically connecting the source region to a source metal disposed on top of an insulation layer wherein a trench bottom surface of the trenched source contact further covered with a conductive material to function as an integrated Schottky barrier diode in said active cell. A shielding structure is disposed at the bottom and insulated from the trenched gate to provide shielding effect for both the trenched gate and the Schottky diode.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: November 18, 2008
    Assignee: Alphs & Omega Semiconductor, Ltd.
    Inventors: Anup Bhalla, Sik K. Lui
  • Patent number: 7439183
    Abstract: A method of manufacturing a semiconductor device. In the method, a thin film is formed on an Si substrate having face orientation (100), that part of the thin film, which lies on an element-isolating region, is removed. Then, the Si substrate is subjected to selective etching, making a trench in the substrate to isolate an element, by using the thin film as mask and a mixture solution of hydrofluoric acid and ozone water.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: October 21, 2008
    Assignees: Kabushiki Kaisha Toshiba, Seiko Epson Corporation
    Inventors: Kunihiro Miyazaki, Hiroyuki Matsuo, Toshiki Nakajima
  • Patent number: 7436017
    Abstract: Methods of manufacturing a semiconductor integrated circuit using selective disposable spacer technology and semiconductor integrated circuits manufactured thereby: The method includes forming a plurality of gate patterns on a semiconductor substrate. Gap regions between the gate patterns include first spaces having a first width and second spaces having a second width greater than the first width. Spacers are formed on sidewalls of the second spaces, and spacer layer patterns filling the first spaces are also formed together with the spacers. The spacers are selectively removed to expose the sidewalls of the first spaces. As a result, the semiconductor integrated circuit includes wide spaces enlarged by the removal of the spacers and narrow and deep spaces filled with the spacer layer patterns.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: October 14, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sang-Eun Lee, Yun-Heub Song
  • Patent number: 7435647
    Abstract: A flash memory device that has a structure capable of preventing gate stack damage, and a method of manufacturing the same, is presented. The method includes forming a first photo resist pattern to open a common source region on a substrate where a shallow trench isolation region, a tunnel oxide layer, and a gate stack including a floating gate, a dielectric layer and a control gate are formed, removing an insulating layer in the shallow trench isolation region with using the first photo resist pattern as a mask, and removing the first photo resist pattern. The method further includes depositing a buffer oxide layer on surface of the substrate to cover the gate stack and the common source region, forming a second photo resist pattern on surface of the substrate including the buffer oxide layer to open the common source region, and injecting dopants to the common source region by using the second photo resist pattern as a mask.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: October 14, 2008
    Assignee: Olympus Corporation
    Inventor: Dong Oog Kim
  • Publication number: 20080246082
    Abstract: A semiconductor power device includes trenched semiconductor power device comprising a trenched gate surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a substrate. The semiconductor power device further includes an insulation layer covering the trenched semiconductor power device with a source-body contact trench opened therethrough the source and body regions and extending into an epitaxial layer below the body regions and filled with contact metal plug therein. The semiconductor power device further includes an embedded Schottky diode disposed near a bottom of the source-body contact trench below the contact metal plug wherein the Schottky diode further includes a Schottky barrier layer having a barrier height for reducing a leakage current through the embedded Schottky diode during a reverse bias between the drain and the source.
    Type: Application
    Filed: April 4, 2007
    Publication date: October 9, 2008
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 7432189
    Abstract: A method for reducing capacitances between semiconductor device wirings is provided. A sacrificial layer is formed over a dielectric layer. A plurality of features are etched into the sacrificial layer and dielectric layer. The features are filled with a filler material. The sacrificial layer is removed, so that parts of the filler material remain exposed above a surface of the dielectric layer, where spaces are between the exposed parts of the filler material, where the spaces are in an area formerly occupied by the sacrificial layer. Widths of the spaces between the parts of the filler material are shrunk with a shrink sidewall deposition. Gaps are etched into the dielectric layer through the shrink sidewall deposition. The filler material and shrink sidewall deposition are removed.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: October 7, 2008
    Assignee: Lam Research Corporation
    Inventors: S. M. Reza Sadjadi, Zhi-Song Huang
  • Patent number: 7427794
    Abstract: The present invention is a semiconductor device comprising a semiconductor body having a top surface and laterally opposite sidewalls formed on a substrate. A gate dielectric layer is formed on the top surface of the semiconductor body and on the laterally opposite sidewalls of the semiconductor body. A gate electrode is formed on the gate dielectric on the top surface of the semiconductor body and adjacent to the gate dielectric on the laterally opposite sidewalls of the semiconductor body.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: September 23, 2008
    Assignee: Intel Corporation
    Inventors: Robert S. Chau, Brian S. Doyle, Jack Kavalieros, Douglas Barlage, Suman Datta, Scott A. Hareland
  • Publication number: 20080211018
    Abstract: This semiconductor device includes a trench gate transistor including a groove formed on a semiconductor, a gate electrode formed in the groove via a gate insulating film, and a source and a drain disposed near the gate electrode on the semiconductor substrate via the gate insulating film. The gate electrode extends from an inner side of the groove to an outer side of the groove. The gate electrode has a misalignment portion in a width direction from the inner side of the groove to the outer side of the groove. The misalignment portion of the gate electrode is formed at a side higher than an opening edge of the groove. A height from the opening edge of the groove to the misalignment portion is larger than a thickness of the gate insulating film.
    Type: Application
    Filed: December 27, 2007
    Publication date: September 4, 2008
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Yoshikazu MORIWAKI
  • Publication number: 20080191274
    Abstract: A power semiconductor device that includes a trench power MOSFET with deep source field electrodes and an integrated Schottky diode.
    Type: Application
    Filed: February 8, 2008
    Publication date: August 14, 2008
    Inventors: Timothy Henson, Dev Alok Girdhar
  • Publication number: 20080191257
    Abstract: A field-effect transistor includes a source region, a drain region and a channel region between the source and the drain region. A gate electrode is also arranged between them, where a lower edge of the gate electrode is formed below a lower edge of at least one of the source and drain regions. A first insulator structure is provided between the gate electrode and the source region. A second insulator structure is provided between the gate electrode and the drain region. The first and the second insulator structures are formed asymmetric and may be adapted to different requirements. The asymmetric approach may provide longer transistor channels, a lower resistance of the gate electrode and smaller footprints for 3D-channel-transistors of, for example, array and support transistors in memory cells or power applications.
    Type: Application
    Filed: February 13, 2007
    Publication date: August 14, 2008
    Applicant: Qimonda AG
    Inventors: Dietmar Temmler, Alexander Sieck
  • Patent number: 7408223
    Abstract: The invention relates to a trench MOSFET with drain (8), sub-channel region (10) body (12) and source (14). The sub-channel region is doped to be the same conductivity type as the body (12), but of lower doping density. A field plate electrode (34) is provided adjacent to the sub-channel region (10) 10 and a gate electrode (32) next to the body (12).
    Type: Grant
    Filed: November 26, 2004
    Date of Patent: August 5, 2008
    Assignee: NXP B.V.
    Inventor: Raymond J. E. Hueting
  • Patent number: 7408234
    Abstract: An object of the present invention is to provide a semiconductor device that is able to realize a low on-resistance maintaining a high drain-to-source breakdown voltage, and a method for manufacturing thereof, the present invention including: a supporting substrate; a semiconductor layer having a P? type active region that is formed on the supporting substrate, interposing a buried oxide film between the semiconductor layer and the supporting substrate; and a gate electrode that is formed on the semiconductor layer, interposing a gate oxide film and a part of a LOCOS film between the gate electrode and the semiconductor layer, wherein the P? type active region has: an N+ type source region; a P type body region; a P+ type back gate contact region; an N type drain offset region; an N+ type drain contact region; and an N type drain buffer region that is formed in a limited region between the N type drain offset region and the P type body region, and the N type drain buffer region is in contact with a source sid
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: August 5, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hisao Ichijo, Hiroyoshi Ogura, Yoshinobu Sato, Teruhisa Ikuta
  • Patent number: 7397082
    Abstract: The capacitance between the gate electrode film and the drain layer of semiconductor device is reduced while keeping the resistance low, with the breakdown voltage of the gate insulating film also being maintained at a sufficient level. A trench 10 is formed with the bottom of the trench at a comparatively shallow position in an N-epitaxial layer 18. The thickness of a bottom surface part 16 of a gate electrode film 11 is formed so as to be thicker than other parts of the gate electrode film 11. Also, when a P type body layer 19 is formed, an interface between the P type body layer 19 and an N-epitaxial layer 18 is located at a deeper position than a bottom end of the gate electrode film 11.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: July 8, 2008
    Assignee: Shindengen Electric Manufacturing Co., Ltd.
    Inventors: Toshiyuki Takemori, Masato Itoi, Yuji Watanabe
  • 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: 7382018
    Abstract: In an embodiment, a 3-dimensional flash memory device includes: a gate extending in a vertical direction on a semiconductor substrate; a charge storing layer surrounding the gate; a silicon layer surrounding the charge storing layer; a channel region vertically formed in the silicon layer; and source/drain regions vertically formed on both sides of the channel region in the silicon layer. Integration can be improved by storing data in a 3-dimensional manner; a 2-bit operation can be performed by providing transistors on both sides of the gate.
    Type: Grant
    Filed: February 6, 2006
    Date of Patent: June 3, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-Min Kim, Eun-Jung Yun, Dong-Won Kim, Jae-Man Yoon
  • Publication number: 20080121990
    Abstract: A semiconductor device is provided which is suitable for a DRAM with word lines and configured to have a trench gate transistor and suppress an increase in the capacitance of a word line without affecting the transistor characteristics. The semiconductor device includes a trench gate transistor which is provided with: a trench which is provided with vertical sides and is formed in a semiconductor substrate; a gate electrode which is formed inside the trench via a gate dielectric film; and a source and a drain which are provided at the semiconductor substrate in the vicinity of the gate electrode via the gate dielectric film, wherein at least one of the thickness of the gate dielectric film in a region contacting the source and the thickness of the gate dielectric film in a region contacting the drain are larger than the thickness of the gate dielectric film formed inside the trench.
    Type: Application
    Filed: November 21, 2007
    Publication date: May 29, 2008
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Eiji Hasunuma
  • Patent number: 7378707
    Abstract: A plurality of mesas are formed in the substrate. Each pair of mesas forms a trench. A plurality of diffusion areas are formed in the substrate. A mesa diffusion area is formed in each mesa top and a trench diffusion area is formed under each trench. A vertical, non-volatile memory cell is formed on each sidewall of the trench. Each memory cell includes a fixed threshold element located vertically between a pair of non-volatile gate insulator stacks. In one embodiment, each gate insulator stack includes a tunnel insulator formed over the sidewall, a deep trapping layer, and a charge blocking layer. In another embodiment, an injector silicon rich nitride layer is formed between the deep trapping layer and the charge blocking layer.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: May 27, 2008
    Assignee: Micron Technology, Inc.
    Inventor: Arup Bhattacharyya
  • Patent number: 7371645
    Abstract: Fabrication of recessed channel array transistors (RCAT) with a corner gate device includes forming pockets between a semiconductor fin that includes a gate groove and neighboring shallow trench isolations that extend along longs sides of the semiconductor fin. A protection liner covers the semiconductor fin and the trench isolations in a bottom portion of the gate groove and the pockets. An insulator collar is formed in the exposed upper sections of the gate groove and the pockets, wherein a lower edge of the insulator collar corresponds to a lower edge of source/drain regions formed within the semiconductor fin. The protection liner is removed. The bottom portion of the gate groove and the pockets are covered with a gate dielectric and a buried gate conductor layer. The protection liner avoids residuals of polycrystalline silicon between the active area in the semiconductor fin and the insulator collar.
    Type: Grant
    Filed: December 30, 2005
    Date of Patent: May 13, 2008
    Assignee: Infineon Technologies AG
    Inventors: Klaus Muemmler, Peter Baars, Stefan Tegen
  • Publication number: 20080079070
    Abstract: A semiconductor device having a buried gate line with a shaped gate trench and a method of fabricating the same are disclosed. The semiconductor device includes a trench isolation layer provided in a semiconductor substrate to define a multi-surfaced active region/channel. A gate line extending to the trench isolation layer fills a portion of the gate trench. The gate trench is formed with a series of depressions to accommodate peaks in the channel. The combination of depressions/peaks operate to increase the effective area of the channel, thereby enabling smaller channel semiconductor devices to be formed without increasing the width thereof.
    Type: Application
    Filed: May 1, 2007
    Publication date: April 3, 2008
    Inventors: Hyeoung-Won Seo, Young-Woong Son, Kang-Yoon Lee, Bong-Soo Kim
  • Patent number: 7352036
    Abstract: A semiconductor power device includes a substrate of a first conductivity type and an epitaxial layer of the first conductivity type over and in contact with the substrate. A first trench extends into and terminates within the epitaxial layer. A sinker trench extends from the top surface of the epitaxial layer through the epitaxial layer and terminates within the substrate. The sinker trench is laterally spaced from the first trench, and is wider and extends deeper than the first trench. The sinker trench is lined with an insulator only along the sinker trench sidewalls so that a conductive material filling the sinker trench makes electrical contact with the substrate along the bottom of the trench and makes electrical contact with an interconnect layer along the top of the trench.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: April 1, 2008
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Thomas E. Grebs, Gary M. Dolny
  • Patent number: 7348628
    Abstract: Vertical channel semiconductor devices include a semiconductor substrate with a pillar having an upper surface. An insulated gate electrode is around a periphery of the pillar. The insulated gate electrode has an upper surface at a vertical level lower than the upper surface of the pillar to vertically space apart the insulated gate electrode from the upper surface of the pillar. A first source/drain region is in the substrate adjacent the pillar. A second source/drain region is disposed in an upper region of the pillar including the upper surface of the pillar. A contact pad contacts the entire upper surface of the pillar to electrically connect to the second source/drain region.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: March 25, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jae-man Yoon, Dong-gun Park, Choong-Ho Lee, Seong-Goo Kim, Won-sok Lee, Seung-bae Park
  • Publication number: 20080042195
    Abstract: A semiconductor device includes a recessed-channel-array MOSFET including a gate electrode having a portion received in a recess. The gate insulting film has a first portion made of silicon oxide in contact with the sidewall of the recess and a second portion made of silicon oxynitride in contact with the bottom of the recess. The first portion has an equivalent oxide thickness larger than the equivalent oxide thickness of the second portion to reduce the parasitic capacitance of the gate electrode.
    Type: Application
    Filed: August 10, 2007
    Publication date: February 21, 2008
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Hirohisa YAMAMOTO
  • Patent number: 7332755
    Abstract: A memory device includes an active area protruding from a semiconductor substrate. A recess is formed in the active area. A field oxide layer is formed on the semiconductor substrate. A gate electrode extends across the active area while being overlapped with the recess. A gate insulation layer is interposed between the gate electrode and the active area. Source and drain areas are formed in the active area. The transistor structure above defines a recessed transistor structure if it is sectioned along a source-drain line and defines a Fin transistor structure if it is sectioned along a gate line. The transistor structure ensures sufficient data retention time and improves the current drivability while lowering the back bias dependency of a threshold voltage.
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: February 19, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventors: Se Aug Jang, Yong Soo Kim, Jae Geun Oh, Jae Sung Roh, Hyun Chun Sohn
  • Patent number: 7326995
    Abstract: A trench MIS device is formed in a P-epitaxial layer that overlies an N+ substrate. In one embodiment, the device includes a thick oxide layer at the bottom of the trench and an N-type drain-drift region that extends from the bottom of the trench to the substrate. The thick insulating layer reduces the capacitance between the gate and the drain and therefore improves the ability of the device to operate at high frequencies. Preferably, the drain-drift region is formed at least in part by fabricating spacers on the sidewalls of the trench and implanting an N-type dopant between the sidewall spacers and through the bottom of the trench. The thick bottom oxide layer is formed on the bottom of the trench while the sidewall spacers are still in place. Therefore, in embodiments where the thermal budget of the process is limited following the implant of the drain-drift region, the PN junctions between the drain-drift region and the epitaxial layer are self-aligned with the edges of the thick bottom oxide.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: February 5, 2008
    Assignee: Siliconix incorporated
    Inventors: Mohamed N. Darwish, King Owyang
  • Patent number: 7326961
    Abstract: To provide devices relating to a manufacturing method for a semiconductor device using a laser crystallization method, which is capable of reducing a cost involved in a design change, preventing a grain boundary from developing in a channel formation region of a TFT, and preventing a remarkable reduction in mobility of the TFT, a decrease in an ON current, and an increase in an OFF current due to the grain boundary and to a semiconductor device formed by using the manufacturing method. In a semiconductor device according to the present invention, among a plurality of TFTs formed on a base film, some TFTs are electrically connected to form logic elements. The plurality of logic elements are used to form a circuit. The base film has a plurality of projective portions having a rectangular or stripe shape.
    Type: Grant
    Filed: April 18, 2005
    Date of Patent: February 5, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Atsuo Isobe, Tamae Takano, Hidekazu Miyairi
  • Patent number: 7323745
    Abstract: A power MOSFET is disclosed in which the source and drain regions are reversed from their usual positions and the drain is on the top of the chip (the surface containing the junction pattern diffusions) and the source is on the bottom of the chip. A plurality of spaced trenches are formed in the top surface. One group of trenches contain gate polysilicon and a gate oxide to control an invertible channel region along the trench. A second group of the trenches have a buried source contact at their bottoms which are connected between the N source material to the P channel region to short out a parasitic bipolar transistor.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: January 29, 2008
    Assignee: International Rectifier Corporation
    Inventor: Daniel M. Kinzer
  • Patent number: 7301200
    Abstract: A trench type power MOSgated device has a plurality of spaced trenches lined with oxide and filled with conductive polysilicon. The tops of the polysilicon fillers are below the top silicon surface and are capped with a deposited oxide the top of which is flush with the top of the silicon. Source regions of short lateral extent extend into the trench walls to a depth below the top of the polysilicon. A trench termination is formed having an insulation oxide liner covered by a polysilicon layer, covered in turn by a deposited oxide.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: November 27, 2007
    Assignee: International Rectifier Corporation
    Inventors: Adam I Amali, Naresh Thapar
  • Patent number: 7279710
    Abstract: An integrated circuit transistor is fabricated with a trench gate having nonconductive sidewalls. The transistor is surrounded by an isolation trench filled with a nonconductive material. The sidewalls of the gate trench are formed of the nonconductive material and are substantially free of unetched substrate material. As a result, the sidewalls of the gate trench do not form an undesired conductive path between the source and the drain of the transistor, thereby advantageously reducing the amount of parasitic current that flows between the source and drain during operation.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: October 9, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Michael Smith, Mark Helm, Kirk Prall
  • Patent number: 7276765
    Abstract: A buried transistor particularly suitable for SOI technology, where the transistor is fabricated within a trench in a substrate and the resulting transistor incorporates completely isolated active areas. The resulting substrate has a decreased topography and there is no need for polysilicon (or other) plugs to connect to the transistor, unless desired. With this invention, better control is achieved in processing, particularly of gate length. The substrate having the buried transistor can be silicon oxide bonded to another substrate to form an SOI structure.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: October 2, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Theodore M. Taylor, Won-Joo Kim, John K. Skrovan
  • Patent number: 7268392
    Abstract: A semiconductor device comprises: a first semiconductor region of a first conductivity type; a second semiconductor region of a second conductivity type provided on the first semiconductor region; a trench formed in the second semiconductor region; a thick gate insulating film selectively provided in a center area of a bottom surface of the trench; a thin gate insulating film provided along a periphery of the bottom surface and on a sidewall of the trench; a third semiconductor region of the first conductivity type that is selectively provided below the thin gate insulating film provided along the periphery of the bottom surface of the trench and that extends to the first semiconductor region; a fourth semiconductor region of the first conductivity type selectively provided in the surface of the second semiconductor region; and a gate electrode filling the trench via the gate insulating film.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: September 11, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hironobu Shibata, Noboru Matsuda
  • Patent number: 7265024
    Abstract: A DMOS device having a trench bus structure thereof is introduced. The trench bus structure comprises a field oxide layer formed on a P substrate, and a trench extending from an top surface of the field oxide layer down to a lower portion of the P substrate. A gate oxide layer and a polysilicon bus are formed to fill the trench as a main portion of the bus structure. In addition, an isolation layer and a metal line are formed atop the polysilicon bus and the field oxide layer. An opening is formed in the isolation layer to form connections between the polysilicon bus and the metal line. In specific embodiments, the bus trench and the gate trenches of the DMOS device are formed simultaneously, and the polysilicon bus and the gate electrode are formed simultaneously as well. Therefore, the bus structure is able to form the DMOS transistor without demanding any lithographic step for defining the position of the polysilicon bus.
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: September 4, 2007
    Assignee: Mosel Vitelic, Inc.
    Inventors: Hsin-Huang Hsieh, Chiao-Shun Chuang, Chien-Ping Chang, Mao-Song Tseng
  • Patent number: 7262461
    Abstract: JFET and MESFET structures, and processes of making same, for low voltage, high current and high frequency applications. The structures may be used in normally-on (e.g., depletion mode) or normally-off modes. The structures include an oxide layer positioned under the gate region which effectively reduces the junction capacitance (gate to drain) of the structure. For normally off modes, the structures reduce gate current at Vg in forward bias. In one embodiment, a silicide is positioned in part of the gate to reduce gate resistance. The structures are also characterized in that they have a thin gate due to the dipping of the spacer oxide, which can be below 1000 angstroms and this results in fast switching speeds for high frequency applications.
    Type: Grant
    Filed: April 17, 2006
    Date of Patent: August 28, 2007
    Assignee: Qspeed Semiconductor Inc.
    Inventors: Ho-Yuan Yu, Valentino L. Liva
  • Patent number: 7259424
    Abstract: A method of manufacturing a semiconductor device provided with a MOS field effect transistor having a channel region of a first conduction type formed in a surface layer portion of a semiconductor substrate, a source region of a second conduction type formed on a rim portion of a trench made to penetrate through the channel region, and a base region of the first conduction type formed in the surface layer portion of the semiconductor substrate adjacently to the source region. The method includes: a step of forming a mask layer having a base-region forming opening corresponding to the base region and a trench forming opening corresponding to the trench on the semiconductor substrate in which the channel region is formed; a base-region forming step of introducing impurities through the base-region forming opening; a trench forming step of forming the trench through the trench forming opening; and a step of forming a gate insulation film on an inner wall surface of the trench.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: August 21, 2007
    Assignee: Rohm Co., Ltd.
    Inventor: Kenichi Yoshimochi
  • Patent number: 7253471
    Abstract: A semiconductor structure has a semiconductor substrate (3, 4), on/in whose top side a structure comprising semiconductor layers, metal layers and insulator layers (5) is applied/impressed. An as far as possible contiguous stabilization layer (6, 10) made of metal and/or passivation material is applied on the applied/impressed metal/semiconductor/insulator layer structure (5).
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: August 7, 2007
    Assignee: Infineon Technologies AG
    Inventor: Franz Hirler
  • Patent number: 7253477
    Abstract: In one embodiment, an edge termination structure is formed in a semiconductor layer of a first conductivity type. The termination structure includes an isolation trench and a conductive layer in contact with the semiconductor layer. The semiconductor layer is formed over a semiconductor substrate of a second conductivity type. In a further embodiment, the isolation trench includes a plurality of shapes that comprise portions of the semiconductor layer.
    Type: Grant
    Filed: February 15, 2005
    Date of Patent: August 7, 2007
    Assignee: Semiconductor Components Industries, L.L.C.
    Inventors: Gary H. Loechelt, Peter J. Zdebel, Gordon M. Grivna
  • Patent number: 7253473
    Abstract: A semiconductor device includes: a semiconductor substrate of the first-type; a semiconductor region of the first-type formed on the substrate; a gate electrode a part of which is present within a trench selectively formed in part of the semiconductor region, and an extended top-end to have a wide width via a stepped-portion; a gate insulating-film formed between the trench and the gate electrode along a wall surface of the trench; a base layer of the second-type on the region via the film to enclose a side-wall except a bottom of the trench; a source region of the first-type adjacent to the film outside the trench in the vicinity of a top surface of the base layer; and an insulating-film formed partially between a bottom-surface of the top-end and a top-surface of the source region and formed to have a thickness larger than that of the gate insulating-film within the trench.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: August 7, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazutoshi Nakamura, Syotaro Ono