Patents Examined by Edwin Oh
  • Patent number: 6048802
    Abstract: A method of forming low dielectric insulation between those pairs of conductive lines, of a level of interconnection for integrated circuits, having a gap of about 0.5 microns or less by depositing a nonconformal source with a poor step function for the insulating material, such as silane (SiH.sub.4) as the silicon (Si) source for silicon dioxide (SiO.sub.2), so as to create, in the gap, a large void whose dielectric constant is slightly greater than 1. After all of the conductive lines have received a deposit of conformal insulating material and a flowable insulating material, the composite insulating materials are removed, preferably by etching, from those pairs of conductive lines with a gap of about 0.5 microns or less. Now, a nonconformal insulating material with a poor step function is deposited and creates a large void in the open gaps of 0.5 microns or less. After creating the void, the deposition continues and is planarized at the desired composite thickness of insulation.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: April 11, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Steven Avanzino, Darrell Erb, Robin Cheung, Rich Klein
  • Patent number: 5985740
    Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystal silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is implemented after introducing nickel element to an amorphous silicon film 103. Then, after obtaining the crystal silicon film, another heat treatment is implemented within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. At this time, HCl or the like is added to the atmosphere. A thermal oxide film 106 is formed in this step. At this time, gettering of the nickel element into the thermal oxide film 106 takes place. Next, the thermal oxide film 106 is removed. Thereby, a crystal silicon film 107 having low concentration of the metal element and a high crystallinity can be obtained.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: November 16, 1999
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
  • Patent number: 5969420
    Abstract: On transistors P1, P2, N1 and N2 constituting an NAND gate, interconnection pattern W of metal having high melting point and aluminum interconnection patterns Al1 and Al2 are stacked. A local line LL for connecting transistors P1, P2, N1 and N2 to each other is formed by the interconnection pattern W of metal having high melting point, signal lines SL and SL' for signal input/output between the NAND gate and the outside are formed by aluminum interconnection pattern Al1, and power supply lines VL and VL' for applying power supply potentials Vcc and Vss to the NAND gate are formed by the aluminum interconnection pattern Al2. As compared with the prior art in which the local line LL is formed by the aluminum interconnection pattern Al1, the degree of freedom in layout can be improved and the layout area can be reduced.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: October 19, 1999
    Assignee: Mitsubushi Denki Kabushiki Kaisha
    Inventors: Shigehiro Kuge, Kazutami Arimoto, Masaki Tsukude, Kazuyasu Fujishima
  • Patent number: 5950102
    Abstract: A method for making air-insulated planar metal interconnections having low interlevel capacitance with improved RC time delays for integrated circuits is achieved. The method involves using a multilayer of negative and positive photoresists in which open regions are developed in the negative photoresist for the metal interconnections, and open regions are developed in the positive photoresist for via holes. The open regions are then filled with a Ti/TiN diffusion barrier deposited at room temperature and an electroless plated copper, and polished back using a Dual Damazene to form the interconnecting metal level and the via hole stud. The method is repeated several times to form multilevel metal interconnections. The remaining photoresist is then totally removed by oxygen ashing to leave a free-standing multilevel metal interconnection structure that is conformally coated with a thin Al.sub.2 O.sub.3 passivation layer and having air insulation.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: September 7, 1999
    Assignee: Industrial Technology Research Institute
    Inventor: William W. Y. Lee
  • Patent number: 5943591
    Abstract: A method for forming a scribe line on a semiconductor wafer including the steps of: (a) providing a semiconductor substrate; and (b) sequentially providing a plurality of layers over the semiconductor substrate of alternating conductive and insulating types, where each of the layers is provided with an elongated opening is formed relative to a desired scribe line position, and where the openings of at least some of the plurality of layers are wider than openings of preceding layers such that at least one sidewall of a completed scribe line has a pronounced slope extending outwardly from its base. The structure of the present invention is, therefore, a scribe line having sloped sidewalls that greatly reduces scribe line contamination problems and enhances planarization during subsequent spin-on-material processes. The scribe lines can either be elongated openings in the layers, or an elongated mesa formed in the layers.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: August 24, 1999
    Assignee: VLSI Technology
    Inventors: Edward R. Vokoun, Miguel A. Delgado, Gregory N. Carter, Brian D. Richardson, Rajive Dhar, Elizabeth A. Chambers
  • Patent number: 5943582
    Abstract: The present invention discloses a method for forming DRAM stacked capacitors by utilizing a densified oxide layer as an etch-stop for the wet etching process of an upper oxide layer in forming a contact hole for the stacked capacitor and thus, eliminating the need of a silicon nitride etch-stop layer and the occurrence of numerous processing difficulties normally observed in such stacked capacitor forming process. The lower oxide layer can be formed by a BPTEOS chemistry while the upper oxide layer can be formed by an ozone-TEOS chemistry.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: August 24, 1999
    Assignee: Taiwan Semiconductor Manufacturing Co. Ltd.
    Inventors: Julie Huang, Shing-Long Lee
  • Patent number: 5924011
    Abstract: A method is disclosed for fabricating mixed analog/digital devices without incurring detrimental effects of high temperature forming of analog components such as capacitor and resistor on the silicide contacts of digital devices. Conversely, the possible adverse effects of silicide formation on the analog components is circumvented. These are accomplished by performing the silicidation of the FET device after forming the two electrode plates of the dual layer capacitor while protecting the capacitor with a capacitor protective oxide (CPO). In a second embodiment, local polysilicon (poly-Si) interconnect is formed simultaneously with the formation of the second plate of the capacitor, and the local interconnect is silicidated subsequently and simultaneously with the silicidation of the polysilicon gate and areas above the source/drain regions. In still another third embodiment, a high-value resistor is formed simultaneously with the forming of the second polysilicon electrode of the capacitor.
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: July 13, 1999
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventor: Jenn Ming Huang
  • Patent number: 5915180
    Abstract: A semiconductor device, which has an oxide laver with the thickness thereof being varied from portion to portion of the inner surface of a trench and can be easily produced, and a process of producing the same. An n.sup.+ type single crystal SiC substrate is formed of SiC of hexagonal system having a carbon face with a (0001) face orientation as a surface, and an n type epitaxial layer and a p type epitaxial layer are successively laminated onto the substrate. An n.sup.+ source region is provided within the p type epitaxial layer, and the trench extends through the source region and the epitaxial layer into the semiconductor substrate. The side face of the trench is almost perpendicular to the surface of the epitaxial layer with the bottom face of the trench having a plane parallel to the surface of the epitaxial layer. The thickness of a gate oxide layer, formed by thermal oxidation, on the bottom face of the trench is larger than the thickness of the gate oxide layer on the side face of the trench.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: June 22, 1999
    Assignee: Denso Corporation
    Inventors: Kazukuni Hara, Norihito Tokura, Takeshi Miyajima, Hiroo Fuma, Hiroyuki Kano
  • Patent number: 5909052
    Abstract: Prevention of reduction in the production yield due to the increase in the area of a semiconductor chip permits a sophisticated-performance single-chip semiconductor device to be fabricated. This also permits a many-kind small-amount production of semiconductor devices to be implemented. After plural semiconductor chips 2 and 3 are fabricated separately, only defect-free chips of them are selected. The selected defect-free chips are connected in contact between their side walls of their densest faces of atoms of their substrates so that the surfaces 4a and 4b where elements are to be formed are located in the same plane. Thus, even when the chip area is increased, reduction of the production yield can be prevented, thereby permitting a large-area sophisticated-performance single chip semiconductor device to be fabricated.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: June 1, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Ohta, Hideo Miura, Mitsuo Usami, Masatsugu Kametani, Munetoshi Zen, Noriaki Okamoto
  • Patent number: 5897368
    Abstract: A method includes applying a first seed layer extending over a horizontal surface and via sidewalls of a dielectric material and exposed underlying contact metallization; removing at least some of the first seed layer from the contact metallization and the horizontal surface while leaving a sufficient amount of the first seed layer on the sidewalls as a catalyst for subsequent application of a third seed layer; sputtering a second seed layer over the contact metallization and the horizontal surface; using an electroless solution to react with the first seed layer and apply the third seed layer over the sidewalls; and electroplating an electroplated layer over the second and third seed layers.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: April 27, 1999
    Assignee: General Electric Company
    Inventors: Herbert Stanley Cole, Jr., Wolfgang Daum
  • Patent number: 5893755
    Abstract: A method of polishing semiconductor wafers is provided. The method will not impair the original (pre-polishing) contour of semiconductor wafers, and semiconductor wafers can be polished so as to have high flatness. In the method according to this invention, a silicon rubber sheet 2 is fixed on a base 4, and an abrasive cloth 5 is secured on the silicon rubber sheet 2. A template 1 of thickness close to that of a semiconductor wafer 10 is secured on a backing pad 32. The semiconductor wafer 10 is restrained by the template 1 and is impelled in to contact with the abrasive cloth 5 to polish effectively.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: April 13, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventor: Yuichi Nakayoshi
  • Patent number: 5891771
    Abstract: A shallow trench isolated FET LDD structure that has a low probability of short circuiting at the silicon to trench interface or between the source or drain and the gate (because of a titanium silicide bridge) is described. It is based on an isolation trench having a top portion with vertical sides and a lower portion with sloping sides. With the filled trench in place, along with a polysilicon gate and gate oxide, the thinner, lightly doped, N type layer is formed using ion implantation. Spacers are then formed on the gate but, prior to the second ion implant step, a few hundred Angstroms of silicon is selectively removed from the surface. This causes the trench filler material to extend above the wafer surface and the spacers to extend above the gate. A deeper, more strongly N-type, layer is then formed in the usual way, followed by the standard SALICIDE process for making contact to source, gate, and drain.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: April 6, 1999
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Sheng-Jyh Wu, Jing-Meng Liu, Chao-Chieh Tsai
  • Patent number: 5891782
    Abstract: A method of forming a MOS transistor without a lightly doped drain (LDD) region between the channel region and drain is provided. The channel region is formed from a tilted ion implantation after the deposition of the gate oxide layer. The tilted implantation forms a relatively short channel length, with respect to the length of the gate electrode. The position of the channel is offset, and directly adjoins the source. The non-channel area under the gate, adjacent the drain, replaces the LDD region between the channel and the drain. This drain extension acts to more evenly distribute electric fields so that large breakdown voltages are possible. The small channel length, and eliminated LDD region adjacent the source, act to reduce resistance between the source and drain. In this manner, larger I.sub.d currents and faster switching speeds are obtained. A MOS transistor having a short, offset channel and drain extension is also provided.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: April 6, 1999
    Assignees: Sharp Microelectronics Technology, Inc., Sharp Kabushiki Kaisha
    Inventors: Sheng Teng Hsu, Jong Jan Lee
  • Patent number: 5888898
    Abstract: A patterned metal layer is gap filled with HSQ, an oxide formed thereon by PECVD, e.g., silicon dioxide derived from silane and N.sub.2 O, and planarized. The dielectric constant of the HSQ layer is minimized by baking the deposited HSQ layer in an inert atmosphere, e.g., N.sub.2, before heat soaking in an N.sub.2 O-containing atmosphere for no more than about 10 seconds and subsequent PECVD.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: March 30, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Minh V. Ngo, Khanh Q. Tran, Terri J. Kitson, Lu You, Simon S. Chan, Jean Y. Yang
  • Patent number: 5882990
    Abstract: A method of manufacturing a silicon substrate which optimizes extrinsic gettering during semiconductor fabrication is provided in which phosphorous ions are diffused into the backside surface of a silicon substrate during wafer slice manufacture. Forming gettering sites at the backside surface prior to gate polysilicon deposition, extrinsic gettering is optimized. Initially, both the frontside and backside surfaces of a silicon substrate are subjected to dopant materials. Thereafter, at least one thin film is formed on both the frontside and backside surfaces. The thin films are then removed from the frontside surface along with a layer of the silicon substrate immediately below the frontside surface to a depth of about 10.0 .mu.m. The final polishing step of a typical silicon wafer manufacturing process removes a layer of silicon to a depth of about 10.0 .mu.
    Type: Grant
    Filed: January 7, 1998
    Date of Patent: March 16, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Damon K. DeBusk, Bruce L. Pickelsimer
  • Patent number: 5874779
    Abstract: A semiconductor device includes a substrate, an insulation film formed above the substrate and containing silicon-fluorine bonds, and a titanium-based metal wiring layer formed on the insulation film, the titanium-based metal wiring layer containing fluorine which is diffused from the insulation film and has a fluorine concentration of less than 1.times.10.sup.20 atoms/cm.sup.3.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: February 23, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tadashi Matsuno
  • Patent number: 5869383
    Abstract: An improved alignment mark used by a laser trimming tool to locate fuses in an underlying integrated circuit is formed using conventional processing sequences. The design features high resolution and improved low noise characteristics. The alignment mark is etched in a shallow layer over a metal layer rather than in the metal itself. The edges which are sensed by the scanning alignment laser of the trimming tool have their elevated portions external to the alignment mark. The improved design replaces a prior art design in which the metal mark protruded from a deep area in the site region. Debris in deep areas adjacent to alignment marks etched in metal, is avoided by the improved design. The absence of this debris virtually eliminates noise in the alignment scan thereby greatly reducing alignment errors.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: February 9, 1999
    Assignee: Vanguard International Semiconductor Corporation
    Inventors: Rong-Wu Chien, Kuo-Chang Wu
  • Patent number: 5864175
    Abstract: The present invention provides a method for fabricating modified integrated circuit packages that are ultra-thin and resist warping. The integrated circuit packages are made thinner by removing some of the casing material uniformly from the upper and lower major surfaces of the integrated circuit package. To prevent the resulting ultra-thin integrated circuit package from warping, a thin layer of material with a coefficient of thermal expansion less than that of silicon is mounted to the upper major surface of the package after some of the casing material has been removed uniformly from the upper major surface. Also, a thin layer of material with a coefficient of thermal expansion greater than that of silicon may be mounted to the lower major surface of the package after some of the casing material has been removed uniformly from the lower major surface. The result is an ultra-thin integrated circuit package that is thermally and mechanically balanced to prevent warping.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: January 26, 1999
    Assignee: Staktek Corporation
    Inventor: Carmen D. Burns
  • Patent number: 5834342
    Abstract: A process for manufacturing a thin film transistor for use in a CMOS SRAM circuit is described. A key feature is the formation of two different photoresist masks from the same optical mask. The first photoresist mask is generated using a normal amount of actinic radiation during exposure and is used to protect the gate region during source and drain formation through ion implantation. The second photoresist mask is aligned relative to the gate in exactly the same orientation as the first mask but is given a reduced exposure of actinic radiation. This results, after development, in a slightly larger mask which is used during etching to form the oxide cap that will protect the channel area during the subsequent silicidation step. Making the cap slightly wider than the channel ensures that small lengths of the source and the drain regions that abut the channel are not converted to silicide. Thus, the finished device continues to act as a thin film transistor, but has greatly reduced source and drain resistances.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: November 10, 1998
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Kan-Yuan Lee, Shou-Gwo Wuu, Dun-Nian Yang