With Means To Reduce Substrate Spreading Resistance (e.g., Heavily Doped Substrate) Patents (Class 257/375)
-
Patent number: 6559486Abstract: An etching mask having high etching selectivity for an inorganic interlayer film of SiO2 or Si3N4, an organic interlayer film such as ARC and an electrically conductive film and a contact hole using such an etching mask, a process for forming same and a resultant semiconductor device. On formation of contact holes for connecting wirings disposed through interlayer films of inorganic or organic material (20, 23 in FIG. 2), a thin film of silicon carbide (21 in FIG. 2) having high etching selectivity for any of the inorganic and organic materials is deposited on an interlayer film, and a mask pattern of silicon carbide is formed using a resist pattern (22 in FIG. 2). Thereafter, high aspect ratio contact holes having a size which is exactly same as that of the mask is formed by etching the interlayer film using the silicon carbide mask.Type: GrantFiled: November 30, 2000Date of Patent: May 6, 2003Assignee: NEC Electronics CorporationInventor: Yasuhiko Ueda
-
Patent number: 6552401Abstract: This invention relates to a method and resulting structure, wherein a DRAM may be fabricated by using silicon midgap materials for transistor gate electrodes, thereby improving refresh characteristics of access transistors. The threshold voltage may be set with reduced substrate doping requirements. Current leakage is improved by this process as well.Type: GrantFiled: November 27, 2000Date of Patent: April 22, 2003Assignee: Micron TechnologyInventor: Charles H. Dennison
-
Patent number: 6507080Abstract: A CMOS transistor is provided having a relatively high breakdown voltage. The CMOS transistor includes an N-type epitaxial layer on a P-type substrate. Between the substrate and epitaxial layer are a heavily doped N-type buried layer and a heavily doped P-type base layer. An N-type sink region is proximatethe edge of the NMOS region, and twin wells are in the area surrounded with the sink region. N+ source and drain regions are formed in respective wells. As the sink region is interposed between the drain and isolation regions, a breakdown occurs between the sink and isolation regions when a high voltage is applied. Twin wells are also formed in the PMOS region P+ source and drain regions are formed in respective wells. As the N-type well surrounds the source and bulk regions, a breakdown occurs between a buried region and the isolation region when a high voltage is applied.Type: GrantFiled: January 17, 2001Date of Patent: January 14, 2003Assignee: Fairchild Korea Semiconductor Ltd.Inventors: Kyung-Oun Jang, Sun-Hak Lee
-
Patent number: 6500714Abstract: In a traditional ROM semiconductor process, ROM codes are performed by ion implantation. Due to the limitations of ion implantation energy and threshold control, the implantation for program codes must be performed before forming an inter-layer oxide layer. Therefore, the required delivery time of the process becomes longer. The invention provide a method of manufacturing ROMs that can shorten delivery time by using only one mask to simultaneously form program codes and contact windows.Type: GrantFiled: June 30, 2000Date of Patent: December 31, 2002Assignee: Windbond Electronics Corp.Inventor: Wen-Ying Wen
-
Patent number: 6492684Abstract: An SOI chip having an isolation barrier. The SOI chip includes a substrate, an oxide layer deposited on the substrate, and a silicon layer deposited on the oxide layer. A gate is deposited above the silicon layer. A first metal contact is deposited above the gate to form an electrical contact with the gate. Second and third metal contacts are deposited to form electrical contacts with the silicon layer. The isolation barrier extends through the silicon layer and the oxide layer, and partially into the substrate, to block impurities in the oxide layer outside the isolation barrier from diffusing into the oxide layer inside the isolation barrier. The isolation barrier surrounds the gate, the first metal contact, the second metal contact, and the third metal contact—which define an active chip area inside the isolation barrier. A method of manufacturing the SOI chip is also disclosed.Type: GrantFiled: June 11, 2001Date of Patent: December 10, 2002Assignee: International Business Machines CorporationInventors: Ronald J. Bolam, Subhash B. Kulkarni, Dominic J. Schepis
-
Publication number: 20020105035Abstract: This invention pertains to a method of fabricating a MRAM structure and the resulting structure. The MRAM structure of the invention has the pinned layer recessed within a trench with the upper magnetic layer positioned over it. The method of MRAM fabrication utilizes a spacer processing technique, whereby the upper magnetic layer of the MRAM stack structure is formed between the region defined by the spacers, thereby allowing for self-alignment of the upper magnetic layer over the underlying pinned magnetic layer.Type: ApplicationFiled: January 9, 2002Publication date: August 8, 2002Inventors: Gurtej Sandhu, Roger Lee, Dennis Keller, Trung T. Doan, Max F. Hineman, Ren Earl
-
Patent number: 6420763Abstract: A semiconductor substrate is of a first conductivity type and has a retrograde well impurity concentration. A first of the first conductivity type and having a second impurity concentration with an impurity concentration peak is formed on a main surface of the semiconductor substrate. A first impurity layer of a third impurity concentration comes into contact with the underside of the retrograde well. The third impurity concentration is smaller than the impurity concentration peak of the first impurity concentration and the second impurity concentration. An element is formed on the retrograde well.Type: GrantFiled: August 26, 1997Date of Patent: July 16, 2002Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tomohiro Yamashita, Shigeki Komori, Masahide Inuishi
-
Patent number: 6396109Abstract: A method for making an isolated NMOS transistor (10) in a BiCMOS process includes forming an N− conductivity type DUF layer (19) in a P conductivity type semiconductor substrate (12), followed by forming alternate contiguous N+ and P conductivity type buried regions (30,26) in the substrate (12). A layer of substantially intrinsic semiconductor material (32) is then formed on the substrate (12) in which alternate and contiguous N and P conductivity type wells (35,36) are formed, respectively above and extending to the N+ and P conductivity type buried regions (30,26). Finally, NMOS source and drain regions (48) are formed in at least one of the P conductivity type wells (35). The method is preferably performed concurrently with the construction of a bipolar transistor structure (11) elsewhere on the substrate (12).Type: GrantFiled: September 2, 1999Date of Patent: May 28, 2002Assignee: Texas Instruments IncorporatedInventors: Louis N. Hutter, Jeffrey P. Smith
-
Patent number: 6380595Abstract: The objective of the invention is to make the n-type silicon region, that relatively strongly and adversely affects the dependence of titanium silicide resistance on wire thickness, as small as possible, in common gate electrode wiring with a CMOS structure. The region, into which ions of n-type impurity 6 are implanted, is only the element region of a p-type substrate region, and all the rest of the gate electrode wiring, on the n-type substrate region and field region, is constituted by p-type polysilicon, with relatively good low-resistance titanium silicide formation.Type: GrantFiled: May 19, 1999Date of Patent: April 30, 2002Assignee: Texas Instruments IncorporatedInventor: Akihiko Tanaka
-
Patent number: 6355948Abstract: There is provided a semiconductor integrated circuit device having a macro cell structure including: a rectangular macro cell region formed on a semiconductor substrate; a first diffusion region having the minimum permissible width, formed apart at least by a minimum inter-diffusion distance from both left and right side ends in upper and lower sides of the macro cell region, and formed in the vicinity of both upper and lower ends of the macro cell region; and a second diffusion region in which a well contact is formed. The first diffusion region is electrically connected with the second diffusion region.Type: GrantFiled: October 6, 1999Date of Patent: March 12, 2002Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Takenobu Iwao, Ryuichi Sakano
-
Publication number: 20020020888Abstract: A semiconductor substrate is of a first conductivity type and has a first impurity concentration. A first impurity layer of the first conductivity type and having a second impurity concentration with an impurity concentration peak is formed on a main surface of the semiconductor substrate. A second impurity layer of a third impurity concentration comes into contact with the underside of the first impurity layer. The third impurity concentration is smaller than the impurity concentration peak of the first impurity concentration and the second impurity concentration. An element is formed on the first impurity layer.Type: ApplicationFiled: August 26, 1997Publication date: February 21, 2002Inventors: TOMOHIRO YAMASHITA, SHIGEKI KOMORI, MASAHIDE INUISHI
-
Publication number: 20020011630Abstract: Provided is a semiconductor device having a semiconductor resistance element, which is capable of suppressing a variation in characteristics of the semiconductor resistance element due to an acceptor concentration difficult to be controlled, thereby stably improving the yield of a semiconductor integrated circuit using the semiconductor device. The device includes an n-type semiconductor resistance region formed in the surface of a compound semiconductor substrate, and a p-type buried region formed between the n-type semiconductor resistance region and a substrate region 21S of the compound semiconductor substrate. An acceptor of the p-type buried region is set to be higher than an acceptor concentration in the substrate region and lower than a doner concentration in the n-type semiconductor resistance region, whereby the effect of the acceptor concentration in the substrate on the semiconductor resistance region can be avoided.Type: ApplicationFiled: May 21, 2001Publication date: January 31, 2002Inventor: Tsutomu Imoto
-
Patent number: 6262457Abstract: Additional degrees of freedom are provided for optimizing the component properties by combining two doping profiles. The threshold voltage of NMOS or DMOS transistors can be set through the process parameters involved in the introduction and outward diffusion of the further dopant of the second conductivity type, independently of the deep concentration, since the dopant concentration at the surface can be chosen independently of the dopant concentration at depth. A low film resistance results from the great penetration depth of the semiconductor region through the combination of the two dopant profiles. The low film resistance leads to reduced pinching of the substrate current in an NMOS transistor, and to greater stability against “latch-up”, without substantially increasing the concentration of the dopants in the region of source/drain diffusions, and therefore without unfavorably affecting drain/bulk capacitance.Type: GrantFiled: March 10, 1998Date of Patent: July 17, 2001Assignee: Infineon Technologies AGInventors: Matthias Stecher, Tim Gutheit, Werner Schwetlick
-
Patent number: 6249028Abstract: An FET structure for utilization with a silicon-on-insulator semiconductor device structure. The structure includes a silicon-on-insulator substrate structure. Source and drain diffusion regions are provided on the silicon-on-insulator substrate. An FET body region is interconnected with the source and drain diffusion regions. A gate oxide region is arranged over at least a portion of the body region and the source and drain diffusion regions. A gate region is arranged over at least a portion of the gate oxide region. A diode is interconnected with and provides a conductive pathway between the gate region and the FET body region. The diode is electrically isolated from the FET source and drain regions and inversion channel by a high threshold FET region.Type: GrantFiled: October 20, 1998Date of Patent: June 19, 2001Assignee: International Business Machines CorporationInventors: Andres Bryant, Edward J. Nowak, Minh H. Tong
-
Patent number: 6191449Abstract: A semiconductor device comprises a semiconductor layer formed on an insulation layer, a pair of source and drain diffusion layer formed on a surface of the semiconductor layer, a first gate electrode disposed on the semiconductor layer region interposed between the pair of source and drain diffusion layer through a gate insulation film, a substrate potential control layer coupled to the semiconductor layer in a region interposed between the pair of the source and drain diffusion layer and formed in such a manner that the first gate electrode does not exist thereon, and a second gate electrode disposed to be in contact with the first gate electrode.Type: GrantFiled: September 19, 1997Date of Patent: February 20, 2001Assignee: Kabushiki Kaisha ToshibaInventor: Tomoaki Shino
-
Patent number: 6133610Abstract: An SOI chip having an isolation barrier. The SOI chip includes a substrate, an oxide layer deposited on the substrate, and a silicon layer deposited on the oxide layer. A gate is deposited above the silicon layer. A first metal contact is deposited above the gate to form an electrical contact with the gate. Second and third metal contacts are deposited to form electrical contacts with the silicon layer. The isolation barrier extends through the silicon layer and the oxide layer, and partially into the substrate, to block impurities in the oxide layer outside the isolation barrier from diffusing into the oxide layer inside the isolation barrier. The isolation barrier surrounds the gate, the first metal contact, the second metal contact, and the third metal contact--which define an active chip area inside the isolation barrier. A method of manufacturing the SOI chip is also disclosed.Type: GrantFiled: January 20, 1998Date of Patent: October 17, 2000Assignee: International Business Machines CorporationInventors: Ronald J. Bolam, Subhash B. Kulkarni, Dominic J. Schepis
-
Patent number: 6075271Abstract: 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: GrantFiled: March 3, 1998Date of Patent: June 13, 2000Assignee: Motorola, Inc.Inventor: Jeremy C. Smith
-
Patent number: 6069389Abstract: A semiconductor flash memory device includes floating gate type field effect transistors serving as memory cells, field effect transistors for forming peripheral circuits and bipolar transistors for forming other peripheral circuits expected to drive heavy load at high speed, and both of the floating gate electrodes and the emitter electrodes and both of the control gate electrodes and the gate electrodes are patterned from a first doped polysilicon and a second doped polysilicon so as to simplify a process sequence for fabricating the semiconductor flash memory device.Type: GrantFiled: October 17, 1997Date of Patent: May 30, 2000Assignee: NEC CorporationInventor: Masakazu Sasaki
-
Patent number: 5977590Abstract: An n.sup.- well region is formed at a surface of a semiconductor substrate. A MOS transistor of high breakdown voltage having a drain region and a source region is formed at the surface of the n.sup.- well region. The n.sup.- well region has an impurity concentration peak right below the drain region. Accordingly, a semiconductor device having a high breakdown voltage insulation gate type field effect transistor that can suppress increase of a depletion layer when high voltage is applied across the drain, that can reduce the electric field intensity across the drain, and that has superior breakdown voltage, and a fabrication method thereof, are obtained.Type: GrantFiled: July 10, 1998Date of Patent: November 2, 1999Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Seiji Suzuki
-
Patent number: 5915188Abstract: An integrated inductor-capacitor (L-C) structure can be formed on a semiconducting substrate (10) by depositing a metal layer in a pattern that contains an inductor coil (14) and a capacitor bottom electrode (12). A CuFe.sub.2 O.sub.4 film (16) is then deposited on the substrate and over the metal pattern to form the dielectric portion of the L-C structure. A via (17) created in the CuFe.sub.2 O.sub.4 film exposes a portion of the inductor coil. Another metal layer (18) is then deposited over the CuFe.sub.2 O.sub.4 film and in the via, such that this metal layer is electrically connected to the inductor coil through the via. A pattern is also made in the second metal layer to form a top electrode (19) for the capacitor, over the corresponding capacitor bottom electrode, and to form a circuit interconnect to the inductor coil through the via.Type: GrantFiled: December 22, 1997Date of Patent: June 22, 1999Assignee: Motorola, Inc.Inventors: E. S. Ramakrishnan, Douglas H. Weisman
-
Patent number: 5831316Abstract: A multi-finger MOS transistor element is provided in which all of the base resistance values of parasitic bipolar transistors (NPN, if an NMOS, or PNP, if a PMOS transistor) in each finger MOS are equal to each other. Thus, each finger MOS transistor element in the multi-finger MOS transistor is turned on simultaneously to enhance ESD protection performance. In the multi-finger MOS transistor, the diffusion region for providing the well/substrate contact is distributed in the source region to make the base resistance value of the parasitic NPN (or PNP) transistor in each finger MOS equal to each other.The multi-finger MOS of the invention includes a plurality of drain regions, each having drain contacts, a plurality of source regions, each having source contacts, and a plurality of gate regions, wherein each gate region is between each drain region and the source region; a bias diffusion region formed in the source region along a middle line which is equally spaced between the pair of gate regions.Type: GrantFiled: January 2, 1997Date of Patent: November 3, 1998Assignee: Winbond Electronics Corp.Inventors: Ta-Lee Yu, Konrad Young
-
Patent number: 5821589Abstract: CMOS vertically modulated wells are constructed by using a blanket implant to form a blanket buried layer and then using clustered MeV ion implantation to form a structure having a buried implanted layer for lateral isolation in addition to said blanket buried layer.Type: GrantFiled: March 19, 1997Date of Patent: October 13, 1998Assignee: Genus, Inc.Inventor: John O. Borland
-
Patent number: 5789786Abstract: A low-voltage 0.8-micron CMOS process is modified by implanting arsenic or phosphorus during epitaxy in a p-type substrate starting material to increase the depth of selected n-well areas for the purpose of producing high-voltage transistors on the same substrate in the same CMOS process. Implanting boron in a p-field extension area in a manner which minimizes the dopant in the adjacent field oxide achieves a similar result. That is, breakdown and punch-through voltages are increased. Together, these make CMOS transistors which operate at a higher voltage range than either innovation alone.Type: GrantFiled: November 25, 1996Date of Patent: August 4, 1998Assignee: National Semiconductor CorporationInventors: Husam Gaffur, Sukyoon Yoon
-
Patent number: 5731619Abstract: A CMOS integrated circuit with field isolation including an NFET(s) having an isolated P-well, wherein the isolated P-well is adjusted so that it does not extend below the field isolation (e.g., STI) and the width and doping of the P-well and an underlying buried N-well is adjusted so that the depletion regions of the source/drain (S-D) diode and also the well-diode just meet (merge) without overlap in the P-well. The semiconductor device obtains bipolar effect and reduced junction capacitance in a bulk single-crystal technology. A method for fabricating the semiconductor device if also provided.Type: GrantFiled: May 22, 1996Date of Patent: March 24, 1998Assignee: International Business Machines CorporationInventor: Seshadri Subbanna
-
Patent number: 5648672Abstract: A semiconductor device comprises a semiconductor substrate formed with at least one well containing impurity ions of either a first conductivity type or a second conductivity type; a plurality of transistors each having a gate insulation film formed on the well, a gate electrode formed on the gate insulation film and a pair of diffusion layers formed in the well; and an outer diffusion layer of the same conductivity type as that of the well and self-aligned with each of the diffusion layers in an outer periphery thereof within the well; the outer diffusion layer having an impurity concentration sufficient to provide a desired junction withstand voltage and having substantially the same width as that of a depletion layer to be generated when an operational voltage is applied to the corresponding transistor; the impurity of the well being set for a concentration such that a threshold voltage of a parasitic transistor appearing below the gate electrode connecting adjacent transistors is higher than a power supplType: GrantFiled: September 19, 1995Date of Patent: July 15, 1997Assignee: Sharp Kabushiki KaishaInventors: Masahiro Hasegawa, Junichi Tanimoto
-
Patent number: 5578855Abstract: A low-voltage 0.8-micron CMOS process is modified by implanting arsenic or phosphorus during epitaxy in a p-type substrate starting material to increase the depth of selected n-well areas for the purpose of producing high-voltage transistors on the same substrate in the same CMOS process. Implanting boron in a p-field extension area in a manner which minimizes the dopant in the adjacent field oxide achieves a similar result. That is, breakdown and punch-through voltages are increased. Together, these make CMOS transistors which operate at a higher voltage range than either innovation alone.Type: GrantFiled: April 26, 1995Date of Patent: November 26, 1996Assignee: National Semiconductor CorporationInventors: Husam Gaffur, Sukyoon Yoon
-
Patent number: 5525823Abstract: A method for forming field oxide regions on an integrated circuit device includes the steps of providing doped regions for formation of active devices. After the doped regions have been formed, a thick field oxide layer is grown over the entire surface of the device. Field oxide regions are then defined using masking and anisotropic etching steps which provide approximately vertical sidewalls for the field oxide regions, and which do not result in the formation of bird's beaks. Since the active regions are defined prior to formation of the field oxide regions, the active regions extend under the field oxide regions and do not give rise to edge effects.Type: GrantFiled: May 13, 1994Date of Patent: June 11, 1996Assignee: SGS-Thomson Microelectronics, Inc.Inventor: Tsiu C. Chan
-
Patent number: 5424562Abstract: A lateral static induction transistor suited for use as a picture element of a solid state imaging device. The lateral static induction transistor includes a semiconductor substrate of a first conduction type of P type or N type, a first epitaxial layer of the same conduction type as the first conduction type which is formed on the semiconductor substrate, a second epitaxial layer of a second conduction type opposite to the first conduction type which is formed on the first epitaxial layer, a source zone and a plurality of drain zones which are formed in the second epitaxial layer near the surface thereof, and a plurality of gates each thereof being formed so as to partially lie over the source zone and one of the drain zones on the second epitaxial layer through an insulating layer.Type: GrantFiled: October 24, 1994Date of Patent: June 13, 1995Assignee: Nikon CorporationInventor: Mutsumi Suzuki
-
Patent number: 5399895Abstract: A LOCOS oxide film is provided in a main surface of a semiconductor substrate for isolating an element region from another element region. A channel cut layer formed of a P-type impurity is provided under the element region. A P.sup.+ impurity region having a concentration thicker than that of P-type impurity of channel cut layer is formed directly under a bird's beak portion of LOCOS oxide film in the main surface of semiconductor substrate. Therefore, an isolation breakdown voltage of an N-channel transistor region is increased.Type: GrantFiled: February 17, 1994Date of Patent: March 21, 1995Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Tsuyoshi Koga
-
Patent number: 5323043Abstract: A first shallow well 5, a second shallow well 3, a third deep well 4, a fourth shallow well 5' and a fifth shallow well 2 are formed on an electroconductive substrate 1, in which a first and second digital series power supplies DVDD, DVSS are each connected to the first shallow well 5 completely included by the third deep well 4 and the second shallow well 3 partially included by the third deep well 4 respectively, a first and second analog series power supplies AVDD, AVSS are each connected to the fourth and fifth shallow wells 5', 2 not included by the third deep well 4 respectively, a MOS transistor constituting a digital circuit is formed on the surface of the first and second shallow wells 5, 3 to which the digital series power supply is connected and a MOS transistor constituting an analog circuit is formed on the surface of the fourth and fifth shallow wells 5', 2 to which the analog series power supply is connected.Type: GrantFiled: January 13, 1993Date of Patent: June 21, 1994Assignee: NEC CorporationInventors: Madoka Kimura, Yoshio Miyazaki
-
Patent number: 5185275Abstract: A process for improving the high voltage performances of a MOSFET transistor, and suppressing parasitic current induced snap-back behavior by placing a heavily doped P+ region around the grounded source. A first P+ region is placed adjacently to and in contact with the source and its metal lead, and a second P+ region may be placed under and in contact with the source and first P+ region, or form a layer under the entire transistor connected to the source by a P+ plug. Additional grounding of the source may be accomplished by a succession of alternating P+ region and N+ regions along the source edge.Type: GrantFiled: March 30, 1992Date of Patent: February 9, 1993Assignee: Micron Technology, Inc.Inventor: Kirk Prall
-
Patent number: 5160996Abstract: A semiconductor device comprises a semiconductor substrate of a first conductivity type, a well which is a second conductivity type, a buried layer, which is of the first conductivity type, and an insulating isolation layer formed extending to an upper surface of a side region of the well. The buried layer has a first portion of a higher dopant concentration than the semiconductor substrate and formed in a deep region of the semiconductor substrate directly below the well, and a second portion formed in a region of the substrate which is positioned higher than the region in which the first portion is formed. The first and second portions of the buried layer are formed integrally in a region of the semiconductor substrate which is directly below the insulating isolation layer, surround the well within the semiconductor substrate, and have a high concentration of a dopant that is of the first conductivity type at a position which is directly below the insulating isolation layer.Type: GrantFiled: August 9, 1991Date of Patent: November 3, 1992Assignee: Matsushita Electric Industrial Co., Inc.Inventor: Shinji Odanaka
-
Patent number: RE34158Abstract: A monolithic complementary semiconductor device comprising n-type and p-type well regions separated by a dielectric isolation region extending from the surface into the substrate region. The well region includes a highly doped buried region which is located at the bottom of the well region and separates an active region in the wall from the substrate region. The isolation region is deeper than the buried region. The well-to-well isolation is enhanced by the combination of the buried region and the deep dielectric isolation region. Packing density and the high speed operation can also be improved.Type: GrantFiled: August 13, 1991Date of Patent: January 12, 1993Assignee: Hitachi, Ltd.Inventors: Atsuo Watanabe, Takahiro Nagano, Takahide Ikeda, Naohiro Momma, Ryuichi Saito