Vertical Channel Patents (Class 438/212)
-
Publication number: 20010038122Abstract: The invention provides a semiconductor device exhibiting a stable and high breakdown voltage, which is manufactured at a low manufacturing cost. The semiconductor device of the invention includes an n-type silicon substrate; a p-type base region in the surface portion of substrate; an n-type drain region in the surface portion of n-type substrate; a p-type offset region in the surface portion of n-type substrate; an n-type source region in the surface portion of p-type base region; a p-type contact region in the surface portion of p-type base region; a gate electrode above the extended portion of p-type base region extending between n-type source region and n-type substrate (or p-type offset region), with a gate insulation film interposed therebetween; an insulation film on gate electrode and p-type offset region; a source electrode on n-type source region; and a drain electrode on n-type drain region.Type: ApplicationFiled: January 9, 2001Publication date: November 8, 2001Inventors: Kazuo Matsuzaki, Naoto Fujishima, Akio Kitamura, Gen Tada, Masaru Saito
-
Patent number: 6312992Abstract: Thin film transistor and method for fabricating the same, is disclosed, in which a channel width of the thin film transistor is made greater in a narrow area for improving an on/off performance of the thin film transistor, the thin film transistor including a source electrode formed on a substrate, a columnar conductive layer connected to the source electrode, a drain electrode formed on the conductive layer, a gate insulating film formed to cover the conductive layer and the drain electrode, a gate electrode formed on the gate insulating film surrounding the conductive layer, and an insulting film formed between the source electrode and the gate electrode.Type: GrantFiled: September 23, 1998Date of Patent: November 6, 2001Assignee: Hyundai Electronics Industries Co., Ltd.Inventor: Seok Won Cho
-
Publication number: 20010033000Abstract: Field effect transistor structures include a channel region formed in a recessed portion of a substrate. The recessed channel portion permits the use of relatively thicker source/drain regions thereby providing lower source/drain extension resistivity while maintaining the physical separation needed to overcome various short channel effects. The surface of the recessed channel portion may be of a rectangular, polygonal, or curvilinear shape. In a further aspect of the present invention, transistors are manufactured by a process in which a damascene layer is patterned, the channel region is recessed by etch that is self-aligned to the patterned damascene layer, and the gate electrode is formed by depositing a material over the channel region and patterned damascene layer, polishing off the excess gate electrode material and removing the damascene layer.Type: ApplicationFiled: January 26, 2001Publication date: October 25, 2001Inventor: Kaizad R. Mistry
-
Patent number: 6307231Abstract: In a method of fabricating a semiconductor device having a MISFET of trench gate structure, a trench is formed from a major surface of a semiconductor layer of first conductivity type which serves as a drain region, in a depth direction of the semiconductor layer, a gate insulating film including a thermal oxide film and a deposited film is formed over the internal surface of the trench, and after a gate electrode has been formed in the trench, impurities are introduced into the semiconductor substrate of first conductivity type to form a semiconductor region of second conductivity type which serves as a channel forming region, and impurities are introduced into the semiconductor region of second conductivity type to form the semiconductor region of first conductivity type which serves as a source region.Type: GrantFiled: July 21, 2000Date of Patent: October 23, 2001Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.Inventors: Sumito Numazawa, Yoshito Nakazawa, Masayoshi Kobayashi, Satoshi Kudo, Yasuo Imai, Sakae Kubo, Takashi Shigematsu, Akihiro Ohnishi, Kozo Uesawa, Kentaro Oishi
-
Publication number: 20010028085Abstract: A semiconductor device includes a first region of semiconductor material, which is doped to a first concentration with a dopant of a first conductivity type. A gate trench formed within the first region has sides and a bottom. A drain access trench is also formed within the first region, which also has sides and a bottom. A second region of semiconductor material is located within the first region and adjacent to and near the bottom of the gate trench. The second region extends to a location adjacent to and near the bottom of the drain access trench. The second region is of the first conductivity type and has a higher dopant concentration than the first region. A gate electrode is formed within the gate trench. A layer of gate dielectric material insulates the gate electrode from the first and second regions. A drain region of semiconductor material is located within the drain access trench. The drain region is of a first conductivity type and has a higher dopant concentration than the first region.Type: ApplicationFiled: June 1, 2001Publication date: October 11, 2001Inventor: Richard A. Blanchard
-
Patent number: 6300199Abstract: A method of defining at least two different field effect transistor channel lengths includes forming a channel defining layer over a substrate, the semiconductor substrate having a mean global outer surface extending along a plane. First and second openings are etched into the channel defining layer. The first and second openings respectively have a pair of opposing sidewalls having substantially straight linear segments which are angled from the plane. The straight linear segments of the opposing sidewalls of the first opening are angled differently from the plane than the straight linear segments of the opposing sidewalls of the second opening and are thereby of different lengths. Integrated circuitry includes a first field effect transistor and a second field effect transistor. The first and second field effect transistors have respective channel lengths defined along their gate dielectric layers and respectively have at least some portion which is substantially straight linear.Type: GrantFiled: May 24, 2000Date of Patent: October 9, 2001Assignee: Micron Technology, Inc.Inventor: Alan R. Reinberg
-
Publication number: 20010026006Abstract: Improved methods and structures are provided that are lateral to surfaces with a (110) crystal plane orientation such that an electrical current of such structures is conducted in the <110> direction. Advantageously, improvements in hole carrier mobility of approximately 50% can be obtained by orienting the structure's channel in a (110) plane such that the electrical current flow is in the <110> direction. Moreover, these improved methods and structures can be used in conjunction with existing fabrication and processing techniques with minimal or no added complexity. Embodiments of a method of forming an integrated circuit include forming a trench in a silicon wafer. A trench wall of the trench has a (110) crystal plane orientation. A semiconductor device is also formed lateral to the trench wall such that the semiconductor device is capable of conducting an electrical current in a <110> direction. One method of the present invention provides for forming an integrated circuit.Type: ApplicationFiled: May 8, 2001Publication date: October 4, 2001Applicant: Micron Technology, Inc.Inventors: Wendell P. Noble, Leonard Forbes, Alan R. Reinberg
-
Patent number: 6297082Abstract: A fabrication method for a metal oxide semiconductor (MOS) transistor involves forming gate oxide layers of different thicknesses on a core region and a input/output (I/O) region. After forming wells in the substrate, two implantation regions for providing a threshold voltage (VT) adjustment and an anti-punch through layer are formed respectively in a P-well and a N-well of the core region as well as a P-well and a N-well of the I/O region. The method involves forming a pattern mask on the gate oxide layer, wherein the pattern mask has an opening, which may be a channel that corresponds to the P-well of the core region. With the pattern mask serving as an ion implantation mask, two implantation regions for providing the VT adjustment and the anti-punch through layer are formed in the P-well of the core region. After the pattern mask is removed, the steps described above are repeated in order to form implantation regions in other regions, but the sequence of the steps can be swapped around at will.Type: GrantFiled: August 25, 1999Date of Patent: October 2, 2001Assignee: United Microelectronics Corp.Inventors: Tony Lin, Alice Chao, Jih-Wen Chou
-
Patent number: 6297533Abstract: A lateral conduction MOS structure characterized by reduced source resistance and reduced pitch. The structure includes a semiconductor substrate having an epitaxial semiconductor layer thereon, the substrate and epitaxial layer being of the same conductivity type. The structure further includes a source layer and a drain layer, each layer being of a second conductivity type, and a channel layer disposed between the source layer and the drain layer. The channel layer has an oxide layer and a gate disposed thereon. At least one of a wet anisotropic and a reactive ion etching step is performed to define a trench having a maximum width of about from 4-6 microns and a depth that extends well into the substrate. An electrically conductive via is then formed by deposition of metal into the trench to thereby establish a low resistance path between the source and the substrate ground.Type: GrantFiled: April 30, 1998Date of Patent: October 2, 2001Assignee: The Whitaker CorporationInventor: Aram Mkhitarian
-
Publication number: 20010024841Abstract: Area efficient static memory cells and arrays containing p-n-p-n transistors which can be latched in a bistable on state. Each transistor memory cell includes a gate which is pulse biased during the write operation to latch the cell. Also provided is a CMOS fabrication process to create the cells and arrays.Type: ApplicationFiled: June 4, 2001Publication date: September 27, 2001Inventors: Wendell P. Noble, Leonard Forbes
-
Patent number: 6294418Abstract: A method and structure for an improved, vertically configured inverter array is provided. The inverter includes a buried gate contact coupling the body regions of a complementary pair of transistors. An electrical contact couples the second source/drain regions of the complementary pair of transistors. The transistors are formed in vertical pillars of single crystalline semiconductor material.Type: GrantFiled: February 29, 2000Date of Patent: September 25, 2001Assignee: Micron Technology, Inc.Inventor: Wendell P. Noble
-
Patent number: 6255699Abstract: A method of forming a pillar CMOS FET device, especially an inverter, and the device so formed is provided. The method includes forming abutting N wells and P wells in a silicon substrate and then forming N+ and P+ diffusions in the P and N wells respectively. A unitary pillar of the epitaxial silicon is grown on the substrate having a base at the substrate overlying both the N and P wells and preferably extending at least from said N+ diffusion to said P+ diffusion in said substrate. The pillar terminates at a distal end. An N well is formed on the side of the pillar overlying the N well in the substrate and a P well is formed on the side of the distal end of the pillar overlying the P well on the substrate and abuts the N well in the pillar. A P+ diffusion is formed in the N well in the pillar adjacent the distal end and a N+ diffusion is formed in the P well in the pillar adjacent the distal end.Type: GrantFiled: May 1, 2000Date of Patent: July 3, 2001Assignee: International Business Machines CorporationInventors: John A. Bracchitta, Jack A. Mandelman, Stephen A. Parke, Matthew R. Wordeman
-
Patent number: 6255689Abstract: A flash memory cell structure and its method of manufacture. The flash memory cell has a vertical configuration. An opening and then a trench are formed in a substrate by etching. The trench (defined as the recessed section of the substrate) is used for forming a shallow trench isolation structure. The substrate region between two neighboring openings (defined as the protruding section of the substrate) is used for forming a common drain and a channel. A source terminal is formed in the substrate at the upper comer next to the shallow trench structure. A tunnel oxide layer is formed over the substrate surface of the opening. A floating gate and a dielectric layer are formed over the tunnel oxide layer. A control gate is formed inside the opening.Type: GrantFiled: December 20, 1999Date of Patent: July 3, 2001Assignee: United Microelectronics Corp.Inventor: Robin Lee
-
Patent number: 6249023Abstract: A gated semiconductor device comprising a substrate defining an active surface area including source regions, and a series of gates formed adjacent and insulated from the source regions. A source electrode contacts the source regions. A termination extends around the periphery of the active surface area, The termination comprises a gate electrode and a layer of conductive material electrically connected between the gate electrode and the gates. The layer of conductive material extends to the source electrode and incorporates a series of regions which are alternately N and P type so as to define a series of breakdown diode junctions distributed around the active surface area and interposed between tie gate electrode and source electrode, In normal operation gate current flows through portions of the conductive layer which do not incorporate diode junctions. In the event that the gate/source voltage exceeds a predetermined level, the diode junctions break down, shorting the gate to the source.Type: GrantFiled: August 17, 1999Date of Patent: June 19, 2001Assignee: Zetex PLCInventor: Adrian David Finney
-
Patent number: 6245615Abstract: Improved methods and structures are provided that are lateral to surfaces with a (110) crystal plane orientation such that an electrical current of such structures is conducted in the <110> direction. Advantageously, improvements in hole carrier mobility of approximately 50% can be obtained by orienting the structure's channel in a (110) plane such that the electrical current flow is in the <110> direction. Moreover, these improved methods and structures can be used in conjunction with existing fabrication and processing techniques with minimal or no added complexity. Embodiments of a method of forming an integrated circuit include forming a trench in a silicon wafer. A trench wall of the trench has a (110) crystal plane orientation. A semiconductor device is also formed lateral to the trench wall such that the semiconductor device is capable of conducting an electrical current in a <110> direction. One method of the present invention provides for forming an integrated circuit.Type: GrantFiled: August 31, 1999Date of Patent: June 12, 2001Assignee: Micron Technology, Inc.Inventors: Wendell P. Noble, Leonard Forbes, Alan R. Reinberg
-
Patent number: 6239465Abstract: A non-volatile semiconductor memory cell array including an MOS transistor having a vertical channel along an inside wall of a trench in each cell is developed for high density integration and high speed operations. One aspect of the invention is that the trench is formed such that the first trench having an aperture is formed slightly deeper than a drain diffusion layer on a semiconductor surface whereas the second trench having a smaller aperture than that of the first trench is formed in a center of a bottom of the first trench extending depthwise to the buried source diffusion layer such that the peripheral width of an aperture section of the first trench in the drain area is larger than that of the second trench in the source area.Type: GrantFiled: September 8, 1999Date of Patent: May 29, 2001Assignee: Fujitsu, Ltd.Inventor: Shinichi Nakagawa
-
Patent number: 6239463Abstract: A power MOSFET or other semiconductor device contains a layer of silicon combined with germanium to reduce the on-resistance of the device. The proportion of germanium in the layer is typically in the range of 1-40%. To achieve desired characteristics the concentration of germanium in the Si-Ge layer can be uniform, stepped or graded. In many embodiments it is desirable to keep the germanium below the surface of the semiconductor material to prevent germanium atoms from being incorporated into a gate oxide layer. This technique can be used in vertical DMOS and trench-gated MOSFETs, quasi-vertical MOSFETs and lateral MOSFETs, as well as insulated gate bipolar transistors, thyristors, Schottky diodes and conventional bipolar transistors.Type: GrantFiled: August 28, 1997Date of Patent: May 29, 2001Assignee: Siliconix incorporatedInventors: Richard K. Williams, Mohamed Darwish, Wayne Grabowski, Michael E. Cornell
-
Patent number: 6232163Abstract: A high voltage tolerant diode structure for mixed-voltage, and mixed signal and analog/digital applications. The preferred silicon diode includes a polysilicon gate structure on at least one dielectric film layer on a semiconductor (silicon) layer or body. A well or an implanted area is formed in a bulk semiconductor substrate or in a surface silicon layer on an SOI wafer. Voltage applied to the polysilicon gate film, electrically depletes it, reducing voltage stress across the dielectric film. An intrinsic polysilicon film may be counter-doped, implanted with a low doped implantation, implanted with a low doped source/drain implant, or with a low doped MOSFET LDD or extension implant. Alternatively, a block mask may be formed over the gate structure when defining the depleted-polysilicon gate silicon diode to form low series resistance diode implants, preventing over-doping the film.Type: GrantFiled: July 28, 1999Date of Patent: May 15, 2001Assignee: International Business Machines CorporationInventors: Steven H. Voldman, Robert J. Gauthier, Jr., Jeffrey S. Brown
-
Patent number: 6225165Abstract: High density static memory cells and arrays containing gated lateral bipolar transistors which can be latched in a bistable on state. Each transistor memory cell includes two gates which are pulse biased during the write operation to latch the cell. Also provided is a CMOS fabrication process to create the cells and arrays.Type: GrantFiled: May 13, 1998Date of Patent: May 1, 2001Assignee: Micron Technology, Inc.Inventors: Wendell P. Noble, Jr., Leonard Forbes
-
Patent number: 6218217Abstract: In a semiconductor device with a high breakdown voltage, insulating layers are buried at regions in n− silicon substrate located between gate trenches which are arranged with a predetermined pitch. This structure increases a carrier density at a portion near an emitter, and improves characteristic of an IGBT of a gate trench type having a high breakdown voltage.Type: GrantFiled: July 18, 2000Date of Patent: April 17, 2001Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Akio Uenishi, Katsumi Nakamura
-
Patent number: 6197640Abstract: A method of manufacturing a semiconductor component includes providing a semiconductor substrate (200) having top and bottom surfaces, forming a drain electrode (160) at the bottom surface of the semiconductor substrate (200), and simultaneously forming source and gate electrodes (251, 254, 255, 253) at the first surface of the semiconductor substrate (200).Type: GrantFiled: December 21, 1998Date of Patent: March 6, 2001Assignee: Semiconductor Components Industries, LLCInventor: Robert B. Davies
-
Patent number: 6194760Abstract: There are provided a double-diffused MOS (Metal Oxide Semiconductor) transistor and a fabricating method thereof. In the double-diffused MOS transistor, a buried layer of a first conductive type and an epitaxial layer of the first conductive type are sequentially formed on a semiconductor substrate, and a gate electrode is formed on the epitaxial layer of the first conductive type with interposition of a gate insulating film. Source and drain regions of the first conductive type are formed in the surface of the epitaxial layer of the first conductive type in self-alignment and non-self-alignment with the gate electrode, respectively. A body region of a second conductive type is formed in the surface of the epitaxial layer of the first conductive type to be surrounded by the source region of the first conductive type, and a bulk bias region of the second conductive type is formed in the body region of the second conductive type under the source region of the first conductive type.Type: GrantFiled: December 18, 1998Date of Patent: February 27, 2001Assignee: Samsung Electronics Co., Ltd.Inventor: Sun-Hak Lee
-
Patent number: 6188105Abstract: A high density MOS-gated device comprises a semiconductor substrate and a doped upper layer of a first conduction type disposed on the substrate. The upper layer comprises a heavily doped source region of the first conduction type and a doped well region of a second and opposite conduction type at an upper surface. The upper surface, which comprises a contact area for the source region, further includes a recessed portion that comprises a contact area for a heavily doped deep body region of the second conduction type in the upper layer underlying the recessed portion. The device further includes a trench gate disposed in the upper layer and comprising a conductive material separated from the upper layer by an insulating layer. A process for forming a high density MOS-gated device comprises providing a semiconductor substrate comprising a doped upper layer of a first conduction type.Type: GrantFiled: April 1, 1999Date of Patent: February 13, 2001Assignee: Intersil CorporationInventors: Christopher B. Kocon, Jun Zeng
-
Patent number: 6168996Abstract: In a method of fabricating a semiconductor device having a MISFET of trench gate structure, a trench is formed from a major surface of a semiconductor layer of first conductivity type which serves as a drain region, in a depth direction of the semiconductor layer, a gate insulating film including a thermal oxide film and a deposited film is formed over the internal surface of the trench, and after a gate electrode has been formed in the trench, impurities are introduced into the semiconductor substrate of first conductivity type to form a semiconductor region of second conductivity type which serves as a channel forming region, and impurities are introduced into the semiconductor region of second conductivity type to form the semiconductor region of first conductivity type which serves as a source region.Type: GrantFiled: August 20, 1998Date of Patent: January 2, 2001Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.Inventors: Sumito Numazawa, Yoshito Nakazawa, Masayoshi Kobayashi, Satoshi Kudo, Yasuo Imai, Sakae Kubo, Takashi Shigematsu, Akihiro Ohnishi, Kozo Uesawa, Kentaro Oishi
-
Patent number: 6143636Abstract: A high density flash EEPROM provides increased nonvolatile storage capacity. A memory cell array includes densely packed memory cells, each cell having a semiconductor pillar providing shared source/drain regions for two vertical floating gate transistors that have individual floating and control gates distributed on opposing sides of the pillar. The control gates are formed together with interconnecting gate lines. First source/drain terminals are row addressable by interconnection lines disposed substantially orthogonal to the gate lines. Second source/drain terminals are column addressable by data lines disposed substantially parallel to the gate lines. Both bulk semiconductor and silicon-on-insulator embodiments are provided. If a floating gate transistor is used to store a single bit of data, an area of only 2F.sup.2 is needed per bit of data, where F is the minimum lithographic feature size. If multiple charge states (more than two) are used, an area of less than 2F.sup.2 is needed per bit of data.Type: GrantFiled: August 20, 1998Date of Patent: November 7, 2000Assignee: Micron Technology, Inc.Inventors: Leonard Forbes, Wendell P. Noble
-
Patent number: 6137135Abstract: The present invention improves the characteristic of a trench-type vertical MOSFET. When a trench 23 serving as a gate 25 is formed, it is made in a shape of ".gamma." which is convex toward the inside of the trench. Thus, the surface area of the trench is reduced so that both gate-source capacitance and gate-drain capacitance can be reduced, thereby shortening the switching time of the MOSFET.Type: GrantFiled: August 7, 1998Date of Patent: October 24, 2000Assignee: Sanyo Electric Co., Ltd.Inventors: Hirotoshi Kubo, Hiroaki Saito, Masanao Kitagawa, Eiichiroh Kuwako
-
Patent number: 6100123Abstract: A method of forming a pillar CMOS FET device, especially an inverter, and the device so formed is provided. The method includes forming abutting N wells and P wells in a silicon substrate and then forming N.sup.+ and P.sup.+ diffusions in the P and N wells respectively. A unitary pillar of the epitaxial silicon is grown on the substrate having a base at the substrate overlying both the N and P wells and preferably extending at least from said N.sup.+ diffusion to said P.sup.+ diffusion in said substrate. The pillar terminates at a distal end. An N well is formed on the side of the pillar overlying the N well in the substrate and a P well is formed on the side of the distal end of the pillar overlying the P well on the substrate and abuts the N well in the pillar. A P.sup.+ diffusion is formed in the N well in the pillar adjacent the distal end and a N.sup.+ diffusion is formed in the P well in the pillar adjacent the distal end.Type: GrantFiled: January 20, 1998Date of Patent: August 8, 2000Assignee: International Business Machines CorporationInventors: John A. Bracchitta, Jack A. Mandelman, Stephen A. Parke, Matthew R. Wordeman
-
Patent number: 6096606Abstract: A semiconductor device (10) is formed in a semiconductor substrate (11) and an epitaxial layer (14). The semiconductor device includes a p-type body region (16), a source region (17), a channel region (19), and a drain region (102) formed in the epitaxial layer (14). Doped regions (20,22) are formed in the epitaxial layer (14) that contain dopant of a conductivity type that is opposite to the epitaxial layer (14). The doped regions (20,22) divide the epitaxial layer (14) to provide or define doped regions (21,23). The doped regions (20,22) are formed from a plurality of doped regions (30,31,32,33) that can be formed with high energy implants.Type: GrantFiled: May 4, 1998Date of Patent: August 1, 2000Assignee: Motorola, Inc.Inventor: Steven L. Merchant
-
Patent number: 6087224Abstract: The manufacture of a trench-gate semiconductor device, for example a MOSFET or IGBT, includes the steps of forming at a surface (10a) of a semiconductor body (10) a first mask (51) having a first window (51a), and later forming a second mask (52) having a smaller window (52a) by providing sidewall extensions (52b) on the first mask (51). A source region (13) is formed by dopant (63) introduced via the first window (51a), whereas a trench (20) is etched at the smaller window (52a) to extend through a body region (15) and into an underlying portion of a drain region (14). The gate (11) is provided in the trench (20) adjacent to where the channel (12) of the device is accommodated. After removing the second mask (52), a source electrode (23) is provided to contact the source region (13) and an adjacent region (15) of the body (10) at the surface (10a).Type: GrantFiled: April 15, 1999Date of Patent: July 11, 2000Assignee: U.S. Philips CorporationInventor: JiKui Luo
-
Patent number: 6048759Abstract: This invention discloses a DMOS power device supported on a substrate of a first conductivity type functioning as a drain. The DMOS power device includes a polysilicon-over-double-gate-oxide gate disposed on the substrate includes a polysilicon layer disposed over a double-gate-oxide structure having a central thick-gate-oxide segment surrounded by a thin-gate-oxide layer with a thickness of about one-fourth to one-half of a thickness of the thick-gate-oxide segment. The DMOS power device further includes a body region of a second conductivity type disposed in the substrate underneath the thin-gate-oxide layer around edges of the central thick-gate-oxide segment the body region extending out laterally to a neighboring device circuit element. The DMOS power device further includes a source region of the first conductivity type disposed in the substrate encompassed in the body region having a portion extending laterally underneath the thin-gate-oxide layer.Type: GrantFiled: February 11, 1998Date of Patent: April 11, 2000Assignee: MagePower Semiconductor CorporationInventors: Fwu-Iuan Hshieh, Koon Chong So, Yan Man Tsui, Danny Chi Nim
-
Patent number: 6037202Abstract: A method for forming a trench transistor structure begins by forming a buried layers (12 and 16) and a doped well (22) in a substrate (10) via epitaxial growth processing. A trench region (24) is then etched into the substrate (10) to expose a the layer (12). A conductive sidewall spacer (28) is formed within the trench (24) as a gate electrode. The spacer (28) gates a first transistor (12, 28, 32) located adjacent a first half of the trench (24) and a second transistor (12, 28, 34) located adjacent a second half of the trench (24). Region (12) is a common electrode wherein the channel regions of both the first and second transistor are coupled in a serial manner through the region (12).Type: GrantFiled: August 18, 1997Date of Patent: March 14, 2000Assignee: Motorola, Inc.Inventor: Keith E. Witek
-
Patent number: 6008518Abstract: A transistor and a fabrication method thereof, and in particular, a technique for compatibly improving reduction of an ON-state voltage and reduction of a turn-off time. First and second emitter layers are selectively formed in isolation from each other on a surface of a base layer 3, and a channel region 6 opposed to a gate electrode 8 through a gate insulating film is formed therebetween. In an ON state, a base current I.sub.b is supplied from a base electrode, while a prescribed gate voltage is applied to the gate electrode. The first and second emitter layers couple with each other and function as a single emitter layer, whereby the ON-state voltage becomes a low value of about the same degree as a bipolar transistor. When bringing a device into an OFF state, supply of the base current I.sub.b is stopped while a zero (or negative) voltage is applied to the gate electrode. Consequently, coupling between the first emitter layer and the second emitter layer is canceled, whereby a second collector current I.Type: GrantFiled: May 6, 1998Date of Patent: December 28, 1999Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Hideki Takahashi
-
Patent number: 5989961Abstract: Disclosed is a method for manufacturing a vertical channel transistor comprising the steps of: selectively implanting a dopant of high concentration into a semiconductor substrate to form a source region; firstly etching the semiconductor substrate using an insulator and a first photoresist pattern as a mask; secondly etching the substrate using a second photoresist pattern having a shape corresponding to said source region as a mask; implanting a dopant of low concentration into the exposed substrate using said second photoresist pattern as a mask to form a vertical channel layer; implanting a dopant of high concentration into the exposed substrate using same mask to form a drain region; activating said dopants, and forming an ohmic contact layer on said drain region; thirdly etching using a third photoresist pattern for exposing the firstly etched portion of the substrate as a mask; depositing a gate metal on the substrate exposed by the thirdly etching; and wiring a metal, respectively.Type: GrantFiled: July 17, 1998Date of Patent: November 23, 1999Assignees: Electronics and Telecommunications Research Institute, Korea TelecomInventors: Jeon Wook Yang, Jae Kyoung Mun, Eung Gie Oh, Jae Jin Lee, Kwang Eui Pyun
-
Patent number: 5973352Abstract: An ultra high density flash EEPROM provides increased nonvolatile storage capacity. A memory array includes densely packed memory cells, each cell having a pillar of semiconductor material that extends outwardly from a working surface of a substrate. The pillar includes source/drain and body regions and has a number of sides. A pair of vertically stacked floating gates is included on at least one of two sides of the pillar. A control gate line also passes through each memory cell. Each memory cell is associated with a control gate line so as to allow selective storage and retrieval of data on the floating gates of the cell. Both bulk semiconductor and silicon-on-insulator embodiments are provided. If a floating gate transistor is used to store a single bit of data, an area of only F.sup.2 is needed per bit of data, where F is the minimum lithographic feature size. If multiple charge states (more than two) are used, an area of less than F.sup.2 is needed per bit of data.Type: GrantFiled: August 20, 1997Date of Patent: October 26, 1999Assignee: Micron Technology, Inc.Inventor: Wendell P. Noble
-
Patent number: 5969384Abstract: A method of fabricating a flash memory having a vertical floating gate terminal layer and controlling gate terminal layer structure, which is suitable for use in ultra-high density IC circuits, and which has two separate tunneling layers, one used for data programming and the other used for data erasure. The fabrication method includes a number of steps. A protruding plateau is first formed on the surface of a silicon substrate. Then, ions are implanted to form a drain region on the top surface of the protruding plateau, as well as to form source regions in the substrate on each side of and adjacent to the base of the protruding plateau. A gate oxide layer is formed on each side wall of the protruding plateau; exposing only part of the side wall of the drain region. A tunnel oxide layer that is thinner than the gate oxide layer, is formed above the surface of the silicon substrate so as to cover the source regions and drain region.Type: GrantFiled: July 26, 1996Date of Patent: October 19, 1999Assignee: United Microelectronics Corp.Inventor: Gary Hong
-
Patent number: 5970343Abstract: In the manufacture of an MOS gated semiconductor device, indentations are provided on a surface of a semiconductor wafer extending inwardly of respective spaced apart regions at the wafer surface having doping concentrations greater than that present in the remainder of the wafer. A layer of silicon having a doping concentration less than that of the substrate is conformally provided on the substrate surface whereby the indentations in the substrate surface are replicated on the surface of the silicon layer. Dopants in the substrate regions are then out-diffused into the silicon layer to provide highly doped buried regions within the layer. Then, using the silicon layer surface indentations as photomask alignment marks, gate electrode structures are formed on and within the silicon layer in preselected orientation relative to the buried regions. The buried regions provide low resistance paths for current through the resulting devices.Type: GrantFiled: August 12, 1998Date of Patent: October 19, 1999Assignee: Harris Corp.Inventor: Christopher Boguslaw Kocon
-
Patent number: 5963800Abstract: The present invention relates to processes for fabrictation of Vertical MISFET devices or a stack of several Vertical MISFET devices having high fabrication yield.Type: GrantFiled: June 17, 1996Date of Patent: October 5, 1999Assignee: Interuniversitair Micro-Elektronica Centrum (IMEC vzw)Inventor: Carlos Jorge Ramiro Proenca Augusto
-
Patent number: 5960275Abstract: This invention shows an improved method for fabricating a MOSFET transistor on a substrate to improve a device ruggedness.Type: GrantFiled: October 28, 1996Date of Patent: September 28, 1999Assignee: MageMOS CorporationInventors: Koon Chong So, Fwu-Iuan Hshieh
-
Patent number: 5943574Abstract: A method of fabricating 3D semiconductor circuits including providing a conductive layer with doped polysilicon thereon patterned and annealed to form first single grain polysilicon terminals of semiconductor devices. Insulated gate contacts are spaced vertically from the terminals so as to define vertical vias and polysilicon is deposited in the vias to form conduction channels. An upper portion of the polysilicon in the vias is doped to form second terminals for the semiconductor devices, and the polysilicon is annealed to convert it to single grain polysilicon. A second electrically conductive layer is deposited and patterned on the second terminal to define second terminal contacts of the semiconductor devices.Type: GrantFiled: February 23, 1998Date of Patent: August 24, 1999Assignee: Motorola, Inc.Inventors: Saied N. Tehrani, Kumar Shiralagi, Herbert Goronkin
-
Patent number: 5918115Abstract: A semiconductor device including: an insulated gate type transistor having a columnar semiconductor region formed on the main side of a semiconductor substrate, a gate electrode formed on the side surface of the columnar semiconductor region while interposing a gate insulating film and main electrode regions respectively formed on and formed below the columnar semiconductor region; and a memory element which is formed on the upper main electrode region and which can be broken electrically.Type: GrantFiled: July 29, 1997Date of Patent: June 29, 1999Assignee: Canon Kabushiki KaishaInventors: Shin Kikuchi, Mamoru Miyawaki, Genzo Monma, Hayao Ohzu, Shunsuke Inoue, Yoshio Nakamura, Takeshi Ichikawa, Osamu Ikeda, Tetsunobu Kohchi
-
Patent number: 5882966Abstract: A BiDMOS device in which a bipolar transistor and a DMOS transistor are formed on the same substrate, thereby resulting in a high degree of integration, and a method of fabricating the same using a reduced number of process steps. A high voltage operating characteristic is achieved because the gate of the DMOS transistor isolates the base and collector of the bipolar transistor. In addition, the junction capacitance between the bipolar base and collector regions is considerably reduced due to the isolation provided by the DMOS gate polysilicon.Type: GrantFiled: September 27, 1996Date of Patent: March 16, 1999Assignee: Samsung Electronics Co., Ltd.Inventor: Young-Soo Jang
-
Patent number: 5828076Abstract: In its gate region (10), a silicon MOS technology component has a surface structure (6) having edges and/or vertices at which inversion regions, suitable as quantum wires or quantum dots, are preferentially formed when a gate voltage is applied. The surface structure is preferably formed as a silicon pyramid (6) by local molecular beam epitaxy.Type: GrantFiled: October 17, 1996Date of Patent: October 27, 1998Assignee: Siemens AktiengesellschaftInventors: Harald Gossner, Ignaz Eisele, Lothar Risch, Erwin Hammerl