Making Plural Insulated Gate Field Effect Transistors Having Common Active Region Patents (Class 438/279)
  • Patent number: 6599804
    Abstract: Short-channel threshold voltage roll-off and punchthrough in an IGFET (40 or 42) having a channel zone (64 or 84) situated in body material (50) are alleviated by arranging for the net dopant concentration in the channel zone to longitudinally reach a local surface minimum at a location between the IGFET's source/drain zones (60 and 62 or 80 and 82) and by arranging for the net dopant concentration in the body material to reach a local subsurface maximum more than 0.1 &mgr;m deep into the body material but not more than 0.4 &mgr;m deep into the body material.
    Type: Grant
    Filed: September 4, 2001
    Date of Patent: July 29, 2003
    Assignee: National Semiconductor Corporation
    Inventors: Constantin Bulucea, Fu-Cheng Wang, Prasad Chaparala
  • Patent number: 6596584
    Abstract: A method for fabricating a flash memory device having a self-aligned source includes providing a semiconductor substrate having a source region separated from a drain region by a channel region. The method also includes forming an isolation structure in the semiconductor substrate that crosses the source, drain, and channel regions of the semiconductor substrate. The method also includes forming a continuous stack structure outwardly from the channel region of the semiconductor substrate and the isolation structure. The method includes depositing a bottom anti-reflective layer over the semiconductor substrate, the isolation structure and the stack structure to substantially uniformly planarize the semiconductor substrate and the isolation structure. The method further includes depositing a photoresist layer over select portions of the bottom anti-reflective layer and the continuous stack structure to form a self-aligned source pattern using a photo mask.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: July 22, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Sarma S. Gunturi, Paul A. Chintapalli
  • Patent number: 6596594
    Abstract: Within a method for fabricating a field effect transistor (FET) device there is provided a series of ion implant methods which provide the field effect transistor (FET) device with both: (1) a source region asymmetrically doped with respect to a drain region; and (2) an asymmetrically doped channel region. The field effect transistor (FET) device is fabricated with enhanced performance.
    Type: Grant
    Filed: February 22, 2002
    Date of Patent: July 22, 2003
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd
    Inventor: Jyh-Chyurn Guo
  • Publication number: 20030124807
    Abstract: A system for fabricating an integrated circuit is disclosed that includes providing a semiconductor substrate (10), and forming a gate oxide layer (12) on an active area on the substrate. A polysilicon gate (14) is formed, on top of the gate oxide, by etching. Etch damage (16) on the substrate surface is repaired by anneal in an inert gas environment—e.g., He, Ne, N2, Ar gas, or combinations thereof.
    Type: Application
    Filed: August 28, 2002
    Publication date: July 3, 2003
    Inventors: Zhiqiang Jeff Wu, Mark S. Rodder, Manoj Mehrotra
  • Patent number: 6586305
    Abstract: Integrated semiconductor circuits have MOS transistors whose gate electrodes are provided with dopings in order to set the electrical potential of the channel area by changing the ionization energy (work function) of the electrons. Transistors in semiconductor circuits, which have both a memory area and a logic area, are produced either using different dopings for pMOS and NMOS transistors in the logic area (dual work function) or using common source/drain electrodes in the memory area (borderless contact), with all the transistors in the semiconductor circuit receiving the same gate doping in the latter case. A method is proposed by which a dual work function and a borderless contact can be produced at the same time. Furthermore, the method results without any additional effort in a trench between the gate layer stacks of the memory area and of the logic area, which prevents lateral ion diffusion.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: July 1, 2003
    Assignee: Infineon Technologies AG
    Inventor: Werner Graf
  • Publication number: 20030113973
    Abstract: A local interconnect fabrication method is disclosed. A nitride spacer is formed on each sidewall of an etched recess formed across a shallow trench isolation region. The spacer prevents contact of metal with the exposed silicon substrate in the recess, and thus reduces leakage. High performance and low energy dissipation of devices can be achieved by reducing undesirable leakage current.
    Type: Application
    Filed: December 17, 2001
    Publication date: June 19, 2003
    Inventor: Tung-Yuan Chu
  • Patent number: 6576513
    Abstract: A NAND-type flash memory device for preventing punchthrough and a method for forming the same are provided. The NAND-type flash memory device includes a string selection transistor, a plurality of cell memory transistors, and a ground selection transistor being sequentially connected in series. The device further includes a bitline contact connected to a drain region of the string selection transistor, and a common source line connected to a source region of the ground selection transistor. Impurities are heavily doped to a drain-to-channel interface in the string selection transistor and a channel-to-source interface in the ground selection transistor, forming pockets for preventing punchthrough. The pockets are preferably formed using a tilted ion implantation using the vertical gate structures as masks.
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: June 10, 2003
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-Sik Yim, Jung-Dal Choi
  • Patent number: 6570234
    Abstract: Annular transistors are positioned with respect to the n-well diffusion region so that the active channels of the transistors are completely within the diffusion region, thereby avoiding the formation of the edges at the boundary between n+ active channel regions and adjacent field oxide region (the bird's beak region), which are susceptible to the effect of the ionizing radiation. The edgeless design of the gate arrays reduces the degradation of the transistors caused by the bird's beak leakage, while allowing for an unmodified commercial process flow for fabrication. An outer annular transistor and one or more inner annular transistors may be provided. The outer transistor may be used as an active transistor in the formation of logic circuits, or may provide isolation for the one or more inner transistors, which may be connected to form logic circuits.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: May 27, 2003
    Assignee: Aeroflex UTMC Microelectronic Systems, Inc.
    Inventor: Harry Gardner
  • Patent number: 6569740
    Abstract: A semiconductor device (10) having a stacked-gate buffer (30) wherein the stacked-gate buffer (30) has a substrate (65) and a top substrate region (70) both with the same first conductivity type. The buffer (30) also has two transistors (95.105), each with a current carrying electrode and a control electrode (90, 100). A deep doped region (120) lies between the first (90) and second (100) control electrodes where the deep doped region (120) is another current carrying electrode for the first transistor (95) and another current carrying electrode for the second transistor (105) and the deep doped region (120) has a second conductivity that is opposite the first conductivity type. A deeper doped region (80) is also part of the stacked-gate buffer which has a second conductivity type and lies between the first (90) and second (100) control electrodes and is deeper than the deep doped region (120). A method of forming the device is also provided herein.
    Type: Grant
    Filed: June 13, 2000
    Date of Patent: May 27, 2003
    Assignee: Motorola, Inc.
    Inventor: Jeremy C. Smith
  • Patent number: 6566204
    Abstract: To furnish an IGFET (120 or 122) with an asymmetrically doped channel zone (144 or 164), a mask (212) is provided over a semiconductor body and an overlying electrically insulated gate electrode (148P or 168P). Ions of a semiconductor dopant species are directed toward an opening (213) in the mask from two different angular orientations along paths that originate laterally beyond opposite respective opening-defined sides of the mask. The location and shape of the opening are controlled so that largely only ions impinging from one of the angular orientations enter the intended location for the channel zone. Ions impinging from the other angular orientation are shadowed by the mask from entering the channel zone location. Although the ions impinging from this other angular orientation do not significantly dope the channel zone location, they normally enter the semiconductor body elsewhere, e.g., the intended location for the channel zone of another IGFET.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: May 20, 2003
    Assignee: National Semiconductor Corporation
    Inventors: Fu-Cheng Wang, Constantin Bulucea
  • Patent number: 6567308
    Abstract: A NAND-type flash memory device for preventing punchthrough and a method for forming the same are provided. The NAND-type flash memory device includes a string selection transistor, a plurality of cell memory transistors, and a ground selection transistor being sequentially connected in series. The device further includes a bitline contact connected to a drain region of the string selection transistor, and a common source line connected to a source region of the ground selection transistor. Impurities are heavily doped to a drain-to-channel interface in the string selection transistor and a channel-to-source interface in the ground selection transistor, forming pockets for preventing punchthrough. The pockets are preferably formed using a tilted ion implantation using the vertical gate structures as masks.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: May 20, 2003
    Assignee: Samsung Electronic Co., Ltd.
    Inventors: Yong-Sik Yim, Jung-Dal Choi
  • Patent number: 6566194
    Abstract: The present invention provides processes for doping and saliciding word lines in a virtual ground array flash memory device without causing shorting between bit lines. According to one aspect of the invention, word lines are doped prior to patterning the poly layer from which the word lines are formed in the core region. Thereby, the poly layer protects the substrate between the word lines from doping that could cause shorting between bit lines. According to another aspect of the invention, word lines are exposed while spacer material, dielectric, or like material protects the substrate between word lines. The spacer material or dielectric prevents the substrate from becoming salicided in a manner that, like doping, could cause shorting between bit lines. The invention provides virtual ground array flash memory devices with doped and salicided word lines, but no shorting between bit lines even in virtual ground arrays where there are no oxide island isolation regions between bit lines.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: May 20, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Mark T. Ramsbey, Yu Sun, Chi Chang
  • Patent number: 6563166
    Abstract: A memory device includes a first memory cell and a second memory cell both controlled by a common control gate. The device includes: a substrate; first and second stacks each including an insulating layer formed over the substrate, a first conductive layer formed over the insulating layer and providing a select gate, and a first dielectric layer formed over the first conductive layer, each of the stacks also including an inner sidewall and an outer sidewall, the. stacks being separated by a common area of the substrate, the inner and outer sidewalls of the stacks being coated with a second dielectric layer; first and second spacers formed adjacent the inner sidewalls of the first and second stacks respectively, the first and second spacers being separated by a medial portion of the common source area of the substrate, each of the spacers.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: May 13, 2003
    Assignee: Mosel Vitelic, Inc.
    Inventor: Cheng-Tsung Ni
  • Patent number: 6559013
    Abstract: A method for fabricating a mask ROM device is described. The method includes forming a buried drain region in a substrate and forming a thick oxide layer on the substrate. Perpendicular to the direction of the buried drain region, a bar-shaped silicon nitride layer is formed on the thick oxide layer. A portion of the thick oxide layer is then removed to expose the substrate, followed by forming a gate oxide layer on the exposed substrate surface for forming a plurality of coded memory cells, wherein the coded memory cells with a gate oxide layer corresponds to a logic state “1” while the code memory cells with a thick silicon oxide layer corresponds to a logic state “0”. A polysilicon layer is then formed on the substrate, followed by back-etching the polysilicon layer to expose the bar-shaped silicon nitride layer. After this, the bar-shaped silicon nitride layer is removed.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: May 6, 2003
    Assignee: Macronix International Co., Ltd.
    Inventor: Jen-Chuan Pan
  • Patent number: 6555435
    Abstract: A method to form contacts in an integrated circuit device comprising to eliminate shorting between adjacent contacts due to dielectric layer voids is achieved. A substrate is provided. Narrowly spaced conductive lines are provided on the substrate. A dielectric layer is deposited overlying the conductive lines and the substrate. The dielectric layer is etched through to the top surface of the substrate in areas defined by lithographic mask to form contact openings between adjacent narrowly spaced conductive lines. An insulating layer is deposited overlying the dielectric layer and filling the contact openings wherein the insulating layer forms a lining layer inside the contact openings and fills any voids in the dielectric layer extending out of the contact openings. The insulating layer is etched through to expose the top surface of the substrate. A conductive layer is deposited overlying the dielectric layer and filling the contact openings. The conductive layer is etched as defined by lithographic mask.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: April 29, 2003
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Ming-Hsiung Chiang, James Wu, Yu-Hua Lee
  • Patent number: 6555436
    Abstract: One aspect of the present invention relates to a method of forming a non-volatile semiconductor memory device, involving the sequential or non-sequential steps of forming a charge trapping dielectric over a substrate, the substrate having a core region and a periphery region; removing at least a portion of the charge trapping dielectric in the periphery region; forming a gate dielectric in the periphery region; forming buried bitlines in the core region; and forming gates in the core region and the periphery region.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: April 29, 2003
    Assignees: Advanced Micro Devices, Inc., Fujitsu Limited
    Inventors: Mark T. Ramsbey, Jean Y. Yang, Hidehiko Shiraiwa, Michael A. Van Buskirk, David M. Rogers, Ravi Sunkavalli, Janet Wang, Narbeh Derhacobian, Yider Wu
  • Publication number: 20030077865
    Abstract: Among first and second oxide films 110 and 112 formed on a substrate 100, the oxide film in a low-breakdown-voltage transistor area LV is all etched off, while the whole surface of the oxide film in a high-breakdown-voltage transistor area HV is left intact. A sixth oxide film 119 to define a side wall is subsequently formed on the whole surface of the substrate 100, and a resist R17 is formed over the whole high-breakdown-voltage transistor area HV. Over-etching of the low-breakdown-voltage transistor area LV is carried out to make the surface of the substrate 100 exposed and to define the side wall only in the low-breakdown-voltage transistor area LV. The oxide film 119 is made to remain in the high-breakdown-voltage transistor area HV. Non-required portions of the oxide films 119 and 112 are then etched off with a resist R15B.
    Type: Application
    Filed: October 17, 2002
    Publication date: April 24, 2003
    Applicant: Seiko Epson Corporation
    Inventors: Atsushi Kanda, Yasushi Haga
  • Patent number: 6551876
    Abstract: Methods of forming electrical connections with an integrated circuitry substrate node location are described. According to one aspect of the invention, a substrate node location is laterally surrounded with insulating material and left outwardly exposed. Conductive material is deposited over the exposed node location. Subsequently, a photomaskless etch of the conductive material is conducted to a degree sufficient to leave a plug of conductive material over the node location. In a preferred implementation, the insulating material with which such node location is surrounded constitutes insulating material portions which are provided relative to conductive lines which are formed over the substrate. In another preferred implementation, such conductive lines form a grid of insulating material which, in turn, defines the node location. According to a preferred aspect of the invention, a plurality of insulated conductive lines are formed over a substrate.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: April 22, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Alan R. Reinberg
  • Patent number: 6551884
    Abstract: A method for forming three gate oxide films having different thicknesses in first through third circuit areas, respectively. The method includes the consecutive steps of forming a first gate oxide film having a largest thickness in all the areas, removing the first gate oxide film and forming a second gate oxide film having a second largest thickness in the second circuit area, and removing the first gate oxide and forming a third gate oxide film having a smallest thickness in the third circuit area. The resultant gate oxide films have accurate thicknesses.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: April 22, 2003
    Assignee: NEC Electronics Corporation
    Inventor: Sadaaki Masuoka
  • Patent number: 6548357
    Abstract: Two different gate conductor dielectric caps are used in the array and support device regions so that the bitline contact can be fabricated in the array region, but a thinner hard mask can be used for better linewidth control in the support device region. The thinner dielectric cap is made into dielectric spacers in the array device regions during support mask etching. These dielectric spacers allow for the array gate conductor resist line to be made smaller than the final gate conductor linewidth. This widens the array gate conductor processing window. The second dielectric cap layer improves linewidth control for the support devices and the array devices. Two separate gate conductor lithography steps and gate conductor dielectric etches are carried out in the present invention to optimize the gate conductor linewidth control in the array and support device regions. The gate conductors in the array and support devices regions are etched simultaneously to reduce production cost.
    Type: Grant
    Filed: April 8, 2002
    Date of Patent: April 15, 2003
    Assignees: International Business Machines Corporation, Infineon Technologies AG
    Inventors: Mary E. Weybright, Gary Bronner, Richard A. Conti, Ramachandra Divakaruni, Jeffrey Peter Gambino, Peter Hoh, Uwe Schroeder
  • Patent number: 6541322
    Abstract: The present invention shows a method of fabricating a MOS transistor on the substrate of a semiconductor wafer and of preventing the gate depletion effects occurring in the MOS transistor. The method involves first forming a silicon oxide layer on the substrate. Then an amorphous silicon layer is formed on the silicon oxide layer followed by forming a silicon germanium (Si1-xGex, x=0.05˜1.0) layer on the amorphous silicon layer. Thereafter, an etching process removes portions of the silicon germanium layer and the amorphous silicon layer so as to form gates of the MOS transistor on the substrate. Finally, a spacer is formed around each gate and a source and a drain of each MOS transistor is formed in the substrate.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: April 1, 2003
    Assignee: Macronix International Co. Ltd.
    Inventor: Kent Kuohua Chang
  • Patent number: 6538269
    Abstract: In a gate array, a gate length is measured by dividing gate electrodes into groups according to their materials to distinguish between those groups. The shape of a contact pad portion (5) of a gate electrode (4) differs according to the groups. A difference described here appears as shape such as cutouts (6a-6c) or projections (6d-6f), which is distinguishable by a scanning electron microscope, for example.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: March 25, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Shigenobu Maeda
  • Patent number: 6537882
    Abstract: The present invention relates to a semiconductor device comprising a first MISFET group and a second MISFET group each formed on a semiconductor substrate. Upon fabrication of it, an MOSFET constituting a memory cell and an MOSFET constituting a peripheral circuit are not formed in the same step. When a side wall is formed on each side of a gate electrode of the MOSFET constituting the peripheral circuit, the memory cell region is covered and protected with a layer which is to be a gate electrode. The semiconductor device thus fabricated has no side walls in the MOSFET constituting a memory cell. According to the present invention, a semiconductor device of high reliability can be fabricated by forming one MOSFET free of side walls. Upon fabrication, it is possible to easily control the size or etching of the device, thereby widening the fabrication range.
    Type: Grant
    Filed: August 15, 1997
    Date of Patent: March 25, 2003
    Assignees: NEC Corporation, NEC Electronic Corporation
    Inventor: Takeo Fujii
  • Publication number: 20030054612
    Abstract: Methods for making a semiconductor structure are discussed. The methods include forming openings in a high-density area and a high-speed area, and forming a metallization layer simultaneously into the high-density area and the high-speed area. The metallization layer includes a combination of substances and compounds that reduce vertical resistance, reduce horizontal resistance, and inhibit cross-diffusion.
    Type: Application
    Filed: August 30, 2001
    Publication date: March 20, 2003
    Inventors: Chih-Chen Cho, Zhongze Wang
  • Patent number: 6531359
    Abstract: A method for fabricating a memory cell array, in particular an EPROM or EEPROM memory cell array, includes burying insulation zones on a silicon substrate in accordance with an STI (Shallow Trench Isolation) technique, forming word lines on the insulation zones, covering the word lines with a hard mask and side wall oxides and CVD depositing an oxide or nitride laterally onto the hard mask and onto the side wall oxides to define a spacer. Spacer channels are etched into the insulation zones between adjoining word lines. An SAS (Self Aligned Source) resist mask is applied to mask each two adjacent coated word lines on mutually facing sections, including the spacer channel located between these word lines, while each two adjacent masked word lines of masked word line pairs remain unmasked on mutually facing sections. The SAS resist mask is exposed.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: March 11, 2003
    Assignee: Infineon Technologies AG
    Inventors: Georg Tempel, Christoph Kutter
  • Patent number: 6528826
    Abstract: A depletion type MOS semiconductor device is provided which includes a p− well region formed in a surface layer of an n− drift layer, an n+ emitter region formed in a surface layer of the p31 well region, an n− depletion region formed in the surface layer of the p− well region, to extend from the n+ emitter region to a surface layer of the n− drift layer, a gate electrode layer formed on a gate insulating film, over the n− depletion region, an emitter electrode formed in contact with surfaces of both of the n+ emitter region and the p− well region, and a collector electrode formed on a rear surface of the n− drift layer. Also provided is a MOS power IC in which the depletion type MOS semiconductor device is integrated with a vertical MOSFET or IGBT. The MOS power IC has a high breakdown voltage, and includes a circuit for feeding back an increase in the potential of the C terminal to the gate (gm) of the MOSFET or IGBT.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: March 4, 2003
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Kazuhiko Yoshida, Motoi Kudoh, Tatsuhiko Fijihira
  • Publication number: 20030040158
    Abstract: A semiconductor device improves the electron mobility in the n-channel MOSFET and reduces the bend or warp of the semiconductor substrate or wafer. The fist nitride layer having a tensile stress is formed on the substrate to cover the n-channel MOSFET. The tensile stress of the first nitride layer serves to relax a compressive stress existing in the channel region. The second nitride layer having an actual compressive stress is formed on the substrate to cover the p-channel MOSFET. The first and second nitride layers serve to decrease bend or warp of the substrate. Preferably, the first nitride layer is a nitride layer of Si formed by a LPCVD process, and the second nitride layer is a nitride layer of Si formed by a PECVD process.
    Type: Application
    Filed: August 21, 2002
    Publication date: February 27, 2003
    Applicant: NEC Corporation
    Inventor: Takehiro Saitoh
  • Publication number: 20030040159
    Abstract: A method of manufacturing an LDMOS transistor comprises providing a semiconductor substrate of a first conductivity type having a well region of a second conductivity type formed on a surface of the substrate. Ions of the first conductivity type are implanted into a part of the well region with a predetermined energy. The substrate is subjected to a heat treatment so that the implanted ions are diffused to form a diffusion region of the first conductivity type on the surface of the substrate. Then, a gate oxide layer and a gate electrode are formed on the surface of the substrate. Finally, a drain region is formed on the surface of the substrate. The predetermined energy for the implantation is set so that an accelerated oxidation during a formation of the gate oxide layer is inhibited.
    Type: Application
    Filed: January 23, 2002
    Publication date: February 27, 2003
    Inventor: Katsuhito Sasaki
  • Patent number: 6521495
    Abstract: A non-volatile memory device and a fabrication method thereof, wherein the non-volatile memory device includes first and second memory cells in a region of a semiconductor substrate where a word line crosses a bit line. Thus, one word line can control the operation of two memory cells, and the device requires less area. Further an intergate dielectric layer extends to the side walls of the floating gate allowing more area and a higher coupling ratio. A lower voltage may therefore be applied to the control gate. During an erasing operation the path of electrons can be redirected toward the substrate. Deterioration of a tunneling insulating layer is thereby reduced or eliminated.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: February 18, 2003
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Moon Shone, Ji-nam Kim
  • Publication number: 20030032245
    Abstract: A NAND-type flash memory device for preventing punchthrough and a method for forming the same are provided. The NAND-type flash memory device includes a string selection transistor, a plurality of cell memory transistors, and a ground selection transistor being sequentially connected in series. The device further includes a bitline contact connected to a drain region of the string selection transistor, and a common source line connected to a source region of the ground selection transistor. Impurities are heavily doped to a drain-to-channel interface in the string selection transistor and a channel-to-source interface in the ground selection transistor, forming pockets for preventing punchthrough. The pockets are preferably formed using a tilted ion implantation using the vertical gate structures as masks.
    Type: Application
    Filed: October 16, 2002
    Publication date: February 13, 2003
    Applicant: Samsung Electronics Co., Ltd
    Inventors: Yong-Sik Yim, Jung-Dal Choi
  • Patent number: 6518130
    Abstract: A semiconductor device comprising a plurality of first transistors formed in a first region of a semiconductor substrate and a plurality of second transistors formed in a second region of the semiconductor substrate, wherein each of the first and second transistors has a gate electrode, a channel-forming region and source/drain regions; the gate electrodes constituting the first and second transistors are formed of a polysilicon layer containing an impurity and a silicide layer formed thereon; a silicide layer is formed in the source/drain regions constituting the first transistor; and no silicide layer is formed in the source/drain regions constituting the second transistor.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: February 11, 2003
    Assignee: Sony Corporation
    Inventor: Keiichi Ohno
  • Publication number: 20030027384
    Abstract: A semiconductor device has, in one embodiment, two wells of different conductivity types formed in a semiconductor substrate. The two wells are arranged to be adjacent to each other to form a junction therebetween. A field oxide film is formed to cover the junction at a main surface of the semiconductor substrate. Other field oxide films or field-shield isolation structures may be formed to isolate circuit elements from one another in the wells.
    Type: Application
    Filed: October 3, 2002
    Publication date: February 6, 2003
    Inventors: Atsushi Kawasaki, Kohei Eguchi, Katsuki Hazama, Fumitaka Sugaya
  • Patent number: 6514823
    Abstract: A memory cell has a pair of n-ch drive MOS transistors, a pair of p-ch access MOS transistors. The access MOS transistor supply electric charge to storage nodes of the drive MOS transistors without using a resistive load. The gate insulation films of the drive MOS transistors have a thickness lower than the thickness of the gate insulation films of the access MOS transistors for achieving stable and high-speed operation of the memory cell.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: February 4, 2003
    Assignee: NEC Corporation
    Inventor: Shingo Hashimoto
  • Publication number: 20030022440
    Abstract: A method of forming flash memory EEPROM devices having a low energy source implant and a high-energy VSS connection implant such that the intrinsic source defect density is reduced and the VSs resistance is low. The source regions are implanted with a low energy, low dosage dopant ions and the VSS regions are implanted with a high energy, high dosage dopant ions.
    Type: Application
    Filed: July 30, 2001
    Publication date: January 30, 2003
    Inventors: Zhigang Wang, Yue-Song He, Richard Fastow
  • Publication number: 20030022426
    Abstract: The present invention relates to a method of manufacturing a semiconductor device which has an isolation region with a trench isolation structure, comprising a trench formed on a semiconductor substrate and a buried insulating film buried within said trench; which comprises the steps of: forming a gate electrode in an active region adjacent to said isolation region on said semiconductor substrate; applying an ion implantation onto said semiconductor substrate using said gate electrode as a mask to form a first dopant diffusion region which is to be used as a LDD region; forming a first insulating film and a second insulating film, in this order, on the entire surface of a principal plane of said semiconductor substrate, inclusive of said gate electrode; performing an etch back, using said first insulating film as an etching stopper, to form a first sidewall of said second insulating film on a lateral face of said gate electrode, with said first insulating film lying therebetween; etching said first insulating
    Type: Application
    Filed: July 18, 2002
    Publication date: January 30, 2003
    Applicant: NEC CORPORATION
    Inventor: Keita Kumamoto
  • Patent number: 6509648
    Abstract: A method of manufacturing a semiconductor device is obtained which is capable of evading generation of a short circuit between wirings in an upper wiring layer even if a part of an upper surface of an FSG film is exposed by variations in a production step. After a USG film (4) is deposited to a thickness of 1 Hm over an entire surface of an FSG film (3), the USG film (4) is polished and removed by a thickness of 900 nm from an upper surface thereof by the CMP method. At this time, part of an upper surface of the FSG film (3) is exposed by variations in a production step. Next, the surface of the interlayer dielectric film (50) is cleaned with a cleaning liquid whose etching rate to the FSG film (3) and etching rate to the USG film (5) are substantially the same. Such a cleaning liquid may be, for example, an ammonia hydrogen peroxide mixture of NH4OH:H2O2:H2O=1:1:20. The structure shown in FIG.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: January 21, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Noboru Morimoto, Masazumi Matsuura, Kinya Goto
  • Patent number: 6503800
    Abstract: The present invention provides a manufacturing method of a semiconductor device having a single semiconductor substrate, for forming a first processing circuit portion and a second processing circuit portion having mutually different thicknesses of gate oxide films on the single semiconductor substrate including the steps of: forming a first gate oxide film over the semiconductor substrate; sequentially forming an insulating film and a first conducting layer over the entire surface of the first gate oxide film; eliminating those portions ranging from the first gate oxide film to the first conducting layer, which portions are included within an element forming region of the first processing circuit portion; and forming, only in the element forming region of the first processing circuit portion, a second gate oxide film having a thickness different from that of the first gate oxide film.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: January 7, 2003
    Assignee: NEC Corporation
    Inventors: Takeshi Toda, Yoshiro Goto
  • Patent number: 6500710
    Abstract: On a SIMOX substrate having a plurality of STI layers and first conductivity type semiconductor layers disposed in the row direction, a stacked-layer structure SS is formed on a gate dielectric film formed on the first conductivity type semiconductor layer, the structure SS being made of a first polysilicon film, a second gate dielectric film and a second polysilicon film. Second conductivity type source and drain regions are formed in the first conductivity type semiconductor layer on both sides of the structure SS. In a plurality of source regions adjacent in the column direction between the stacked-layer structures SS, a common source line CSL is formed which is made of second conductivity type source region connecting semiconductor regions, source regions and conductive films formed on these semiconductor and source regions.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: December 31, 2002
    Assignee: Fujitsu Limited
    Inventor: Shinichi Nakagawa
  • Publication number: 20020197836
    Abstract: A method for forming variable oxide thicknesses across semiconductor chips comprises providing a silicon semiconductor substrate having pre-selected areas open to silicon surface using a photoresist layer; immersing the silicon semiconductor substrate in an HF type electrolytic bath to produce a porous silicon area; and removing the photoresist layer and oxidizing the silicon semiconductor substrate to produce a plurality of thicknesses of gate oxide on the silicon semiconductor substrate.
    Type: Application
    Filed: June 11, 2001
    Publication date: December 26, 2002
    Applicant: International Business Machines Corporation
    Inventors: S. Sundar Kumar Iyer, Suryanarayan G. Hegde, Erin Catherine Jones, Harald F. Okorn-Schmidt
  • Patent number: 6495889
    Abstract: A semiconductor device comprises an SAC structure having side wall spacers and offset nitride films. In particular, in this semiconductor device, the side wall spacers are constituted from lower side wall spacers that are composed of silicon oxide films and are in contact with the lower side of the gate electrode side walls, and upper side wall spacers that are composed of silicon nitride films and are in contact with the upper side of the gate electrodes side walls. As a result thereof, a distance is formed between the substrate and the interface between the silicon nitride film and the silicon oxide film. This suppresses the hot carrier phenomenon and the occurrence of poor contact.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: December 17, 2002
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Akira Takahashi
  • Patent number: 6492227
    Abstract: A method is provided for fabricating memory devices on a semiconductor substrate using a dual damascene process. The method includes the steps of forming at least one dummy gate structure for at least one memory device on the semiconductor substrate, depositing dielectric material on surroundings of the at least one dummy gate structure, etching the dielectric material and the at least one dummy gate structure to form at least one control gate void and at least one floating gate void, forming a gate dielectric layer on a bottom surface of the at least one floating gate void, depositing floating gate material on the gate dielectric layer in the at least one floating gate void to form a floating gate, depositing a dielectric layer on the floating gate, and depositing control gate material on the dielectric layer in the at least one control gate void to form a control gate.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: December 10, 2002
    Assignee: International Business Machines Corporation
    Inventors: Li-Kong Wang, Louis L. Hsu, Wei Hwang
  • Publication number: 20020182803
    Abstract: Provided is, for example, a method for the fabrication of electrical interconnects in semiconductor devices wherein a substrate including two or more transistors having gate regions wherein the gate regions are not exposed (e.g., the gate regions are completely covered by an insulating cap) is provided. An insulating layer overlying the transistors and the active areas is deposited, where upon a hard mask is created and patterned to form a contact plug/interconnect opening over a first active area and a portion of a first transistor immediately adjacent the first active area. A spacer is formed within the contact plug/interconnect opening. Insulating material overlying active areas between transistors is removed. A portion of the gate region of the first transistor is then exposed and interconnect material is deposited within the contact plug/interconnect opening onto the exposed portion of the gate region of the first transistor and the first active area.
    Type: Application
    Filed: June 5, 2001
    Publication date: December 5, 2002
    Applicant: Micron Technology, Inc.
    Inventors: Sanh D. Tang, Daniel Smith, Jason Taylor
  • Publication number: 20020182789
    Abstract: A method of forming a thin film transistor, includes: forming an active region on a first insulating layer, the active region having a channel region, at least one sub-channel region, and first regions disposed between the channel region and each sub-channel region; sequentially forming a second insulating layer and a first conductive layer over the first insulating layer; patterning the second insulating layer and the first conductive layer to form a gate insulating layer and gate electrode on a channel region of the active layer, and to form a sub-gate insulating layer and associated sub-gate electrode on each sub-channel region of the active layer; forming a mask covering at least a portion of the gate electrode, at least a portion of each sub-gate electrode, and each first region of the active region; and implanting impurities into exposed portions of the active region using the mask to form a source region on a first side of the channel region and a drain region on a second side of the channel region suc
    Type: Application
    Filed: July 17, 2002
    Publication date: December 5, 2002
    Applicant: LG Electronics, Inc.
    Inventor: Jae-Deok Park
  • Publication number: 20020179970
    Abstract: In a semiconductor device in which the gate electrode of a MISFET formed on a semiconductor substrate is electrically connected to a well region under the channel of the MISFET, the MISFET is formed in an island-shaped element region formed on the semiconductor substrate, and electrical connection between the gate electrode of the MISFET and the well region in the semiconductor substrate is done on the side surface of the island-shaped element region.
    Type: Application
    Filed: July 23, 2002
    Publication date: December 5, 2002
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Atsushi Yagishita, Tomohiro Saito, Toshihiko Iinuma
  • Patent number: 6486525
    Abstract: An integrated circuit having improved soft error protection and a method improving the soft error protection of an integrated circuit are disclosed. The integrated circuit comprises a substrate 72, a transistor formed in the substrate 72, a first region 74 (e.g. a well) formed in the substrate having a first conductivity type, a second region 84 below the first region 74 having a second conductivity type, and a trench formed in the substrate having a depth at least substantially as deep as the well. The trench 70 is filled with a non-conductive material 71 that forms a frame around the transistor, whereby soft errors due to electron-hole pairs caused by ionizing radiation in the frame are substantially eliminated.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: November 26, 2002
    Assignee: Texas Instruments Incorporated
    Inventor: Thomas J. Aton
  • Publication number: 20020173104
    Abstract: The present invention shows a method of fabricating a MOS transistor on the substrate of a semiconductor wafer and of preventing the gate depletion effects occurring in the MOS transistor. The method involves first forming a silicon oxide layer on the substrate. Then an amorphous silicon layer is formed on the silicon oxide layer followed by forming a silicon germanium (Si1-xGex, x=0.05˜1.0) layer on the amorphous silicon layer. Thereafter, an etching process removes portions of the silicon germanium layer and the amorphous silicon layer so as to form gates of the MOS transistor on the substrate. Finally, a spacer is formed around each gate and a source and a drain of each MOS transistor is formed in the substrate.
    Type: Application
    Filed: May 17, 2001
    Publication date: November 21, 2002
    Inventor: Kent Kuohua Chang
  • Publication number: 20020173105
    Abstract: A method is provided for maximizing activation of a gate electrode while preventing source and drain regions from being excessively doped. The gate electrode is partially doped when exposed the source/drain implantation step. Then, the gate electrode is fully doped by the selective implantation step while the source/drain regions are blocked. Separate annealing steps are provided subsequent to the gate doping step and the source and drain implantation step.
    Type: Application
    Filed: May 15, 2001
    Publication date: November 21, 2002
    Applicant: International Business Machines Corporation
    Inventors: Heemyong Park, Dominic J. Schepis, Fariborz Assaderaghi
  • Patent number: 6482699
    Abstract: A method of manufacturing a semiconductor device is provided in which multi-layer structures are formed on a semiconductor substrate to form core and peripheral regions. Sidewall spacers are formed around the multi-layer structures and source and drain regions are implanted adjacent the sidewall spacers and a stop layer is deposited over the semiconductor substrate after which a dielectric layer is deposited over the stop layer. A first and second photoresist contact masks are deposited, processed, and used to respectively etch core and peripheral contact openings. The first and photoresist contact masks are respectively removed after each etching step.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: November 19, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: YongZhong Hu, Fei Wang, Wenge Yang, Yu Sun, Ramkumar Subramanian
  • Patent number: 6479355
    Abstract: The present invention provides a method for landing pads in the semiconductor devices, comprising the following steps: providing a semiconductor substrates with a plurality of active regions, a plurality of gate structures above the active regions and a plurality of source/drain regions, while each gate structure comprises a top cap layer and sidewall spacers; forming a conductive layer over the substrate; removing a portion of the conductive layer above the gate structure using the top cap layer of the gate structure as a stop layer, so that a height of the conductive layer is lower than a height of the gate structure; forming a patterned mask layer, right above the active regions, over the substrate; performing an etching step to define the conductive layer above the active regions; and removing the patterned mask layer and forming landing pads on the active regions.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: November 12, 2002
    Assignee: United Microelectronics Corp.
    Inventors: King-Lung Wu, Kun-Chi Lin
  • Patent number: 6479339
    Abstract: A mixed voltage CMOS process for high reliability and high performance core transistors and input-output and analog transistors with reduced mask steps. A patterned silicon nitride film 160 is used to selectively mask various implant species during the formation of the LDD regions 180, 220, and the pocket regions 190, 230 of the core transistors 152, 154. The LDD regions 240, 200 of the I/O or analog transistors 156, 158 are simultaneously formed during the process.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: November 12, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Mahalingam Nandakumar, Amitava Chatterjee