Bonding E.g., Electrostatic For Strain Gauges Patents (Class 148/DIG12)
  • Patent number: 5543349
    Abstract: A pressure transducer comprising at least one diaphragm formed in a wafer of semiconducting material, the at least one diaphragm being spaced from a first surface of the wafer, a first layer of semiconducting material disposed over the at least one diaphragm, the first layer forming at least one resonating beam over the at least one diaphragm, and a plurality of resistor elements formed from a third layer of semiconducting material disposed over the at least one resonating beam, and isolation means for dielectrically isolating the at least one resonating beam from the at least one diaphragm.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: August 6, 1996
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Alexander A. Ned
  • Patent number: 5540785
    Abstract: A method for fabricating silicon on insulator structures having a dislocation free silicon layer. The method utilizes low temperature UHVCVD to deposit a very heavily doped etch stop layer having a very steep doping profile onto a substrate and a lightly doped active layer onto the etch stop layer. An insulator is formed on the active layer and a carrier wafer is formed on the insulator layer. The original substrate is removed in a first etch and the etch stop layer is removed in a second etch resulting in a thin, uniform active layer. In one embodiment, a small percentage of germanium is added to the etch stop layer to produce a defect free epitaxial active layer.
    Type: Grant
    Filed: April 4, 1994
    Date of Patent: July 30, 1996
    Assignee: International Business Machines Corporation
    Inventors: Robert H. Dennard, Bernard S. Meyerson, Robert Rosenberg
  • Patent number: 5538904
    Abstract: A method of estimating the amount of boron on the surface of silicone samples in which a plurality of reference samples shallowly ion-implanted with boron in different dosages are prepared and heat-treated under the same conditions of temperature and time as are used in a bonding heat treatment to obtain the bonded wafer, thereafter, the boron profile in the direction of the depth of the bonding interface in each reference sample is measured using a SIMS and compared with an actual boron profile at the bonding interface of a bonded wafer to be estimated so as to determine one reference sample whose boron profile is equivalent to the actual boron profile of the bonded wafer to be estimated, and finally a dosage of boron in the determined reference sample is estimated by convertion to be a surface density of boron presenting at the bonding interface of the bonded wafer to be estimated at an initial stage prior to the bonding heat treatment of the bonded wafer to be estimated.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: July 23, 1996
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Kiyoshi Mitani, Masatake Katayama, Kazushi Nakazawa
  • Patent number: 5523254
    Abstract: A wafer bonding method for forming a SOI structure comprising the steps of bringing wafers into proximity in a state with one wafer a slight, substantially uniform clearance away from the other wafer and pressing one point of at least one wafer of the two wafers against the other wafer. In another aspect of the invention, there is provided a method of positioning for photolithography using an alignment mark portions and/or a vernier portions formed on a SOI substrate, which comprises the step of removing semiconductor layer portions corresponding to the alignment mark portions and/or the vernier portions. In further another aspect of the invention, there is provided a new DRAM semiconductor device formed by using SOI structure, which comprises a new pattern of a strage node formed longitudinally along a word line. Further, there is provided a new DRAM semiconductor device formed by using SOI structure, which comprises a unique strage node having a conductive side wall.
    Type: Grant
    Filed: April 21, 1994
    Date of Patent: June 4, 1996
    Assignee: Sony Corporation
    Inventors: Hiroshi Satoh, Yasunori Ohokubo, Takeshi Matsushita, Toshiyuki Nishihara, Makoto Hashimoto
  • Patent number: 5514235
    Abstract: A method is disclosed for obtaining bonded wafers of SOI type, where impurity redistribution in the bulk of the wafers is suppressed and the bonding strength between the wafers is substantially higher compared with that in the prior art. This is accomplished by forming a thermally grown oxide layer on the surface of the thinner one(bond wafer) of two monocrystalline silicon wafers having thicknesses different from each other by more than 50 .mu.m; then superposing the thinner wafer onto the other thicker wafer(base wafer); and finally conducting at least two heat treatments of the wafers at temperatures selected in the range of under 900.degree. C. for a period of time selected in the range of from 0.5 min. to 120 min.
    Type: Grant
    Filed: June 17, 1994
    Date of Patent: May 7, 1996
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Kiyoshi Mitani, Masatake Katayama
  • Patent number: 5509974
    Abstract: A dissolved wafer process is modified by providing an etch control seal around the perimeter of an etch resistant microstructure, such as a micromechanical or microelectromechanical device, formed on a first substrate. The microstructure is defined and shaped by a surrounding trench in the first substrate. Selected areas of the microstructure and the first substrate are bonded to an etch resistant second substrate. The selected bonding areas may comprise raised areas of the first substrate, or raised areas of the second substrate corresponding to the selected bonding areas of the first substrate. A bonded area forming a ring extending around the perimeter of the microstructure and its defining trench forms an etch control seal. The first substrate of the bonded assembly is dissolved in a selective etch so that the etch resistant microstructure remains attached to the second substrate only at the bonded areas.
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: April 23, 1996
    Assignee: Rockwell International Corporation
    Inventor: Kenneth M. Hays
  • Patent number: 5506153
    Abstract: Controllable power semiconductor components such as, for example, IGBTs and thyristors are provided, which, compared to known components, have a relatively lightly doped n-buffer zone, a relatively flat p-emitter, and an n-base having a comparatively long charge carrier life expectancy. An advantage is achieved that the controllable power semiconductor component has a temperature-independent tail current, despite a low on-state dc resistance and a high blocking voltage.
    Type: Grant
    Filed: June 13, 1995
    Date of Patent: April 9, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventors: Heinrich Brunner, York C. Gerstenmaier
  • Patent number: 5504036
    Abstract: A method is provided of manufacturing a semiconductor device whereby semiconductor elements (5) and conductor tracks (14) are formed on a first side (2) of a semiconductor slice (1) which is provided with a layer of semiconductor material (4) disposed on an insulating layer (3). Then the semiconductor slice (1) is fastened with said first side (2) to a support slice (15), after which material is removed from the semiconductor slice (1) from the other, second side (17) until the insulating layer (3) has become exposed. The insulating layer (3) is provided with contact windows (18) in which conductive elements (19) are provided. This is done from the first side (2) of the semiconductor slice (1) before the latter is fastened to the support slice (15). The semiconductor elements (5) are externally contacted with a contact wire (20) via the conductive elements (19).
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: April 2, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Ronald Dekker, Henricus G. R. Maas, Wilhelmus T. A. J. van den Einden
  • Patent number: 5504032
    Abstract: A high precision micromechanical accelerometer comprises a layered structure of five (5) semiconductor wafers insulated from one another by thin semiconductor material oxide layers. The accelerometer is formed by first connecting a coverplate and a baseplate to associated insulating plates. Counter-electrodes, produced by anisotropic etching from the respective insulating plates, are fixed to the coverplate and the baseplate respectively. The counter-electrodes are contactable through the cover or baseplate via contact windows. A central wafer contains a unilaterally linked mass (pendulum) that is also produced by anisotropic etching and which serves as a movable central electrode of a differential capacitor. The layered structure is hermetically sealed by semiconductor fusion bonding. A stepped gradation from the top is formed at a wafer edge region for attaching contact pads to individual wafers to permit electrical contacting of individual wafers. The invention permits fabrication of a .mu.
    Type: Grant
    Filed: April 7, 1994
    Date of Patent: April 2, 1996
    Assignee: LITEF GmbH
    Inventors: Thomas Gessner, Martin Hafen, Eberhard Handrich, Peter Leinfelder, Bruno Ryrko, Egbert Vetter, Maik Wiemer
  • Patent number: 5496764
    Abstract: An insulating layer is formed over a first substrate. Trenches are formed within a second substrate, and those trenches are filled with an insulating layer. The two substrate are bonded at their insulating layers. The portion of the second substrate away from the trenches is removed to form semiconductor regions over the insulating layer of the first substrate. Embodiments of the present invention allow better thickness control for SOI regions and lower leakage current compared to SOI layers that use LOCOS-type field isolation.
    Type: Grant
    Filed: July 5, 1994
    Date of Patent: March 5, 1996
    Assignee: Motorola, Inc.
    Inventor: Shih-Wei Sun
  • Patent number: 5496760
    Abstract: A dielectrics dividing wafer, and a method of manufacturing the wafer, is disclosed in which embedded dielectric films are provided in the interior of the wafer in a predetermined pattern extending laterally parallel to a face surface of the wafer, and partition dielectric films, in the form of vertical walls extending from the face surface and the rear surface of the wafer, to the embedded dielectric films, are provided to define semiconductor areas extending continuously from the face surface of the wafer to the rear surface of the wafer. The semiconductor areas can be used for vertical circuit elements. The partition dielectric films in conjunction with the embedded dielectric films and the face surface of the wafer also define additional planar semiconductor areas that can be used for planar structure circuit elements.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: March 5, 1996
    Assignee: Fuji Electric Company, Ltd.
    Inventor: Kazuo Matsuzaki
  • Patent number: 5494849
    Abstract: A single-etch stop process for the manufacture of silicon-on-insulator substrates. The process includes forming a silicon-on-insulator bonded substrate comprising a handle wafer, a device wafer, a device layer having a thickness of between about 0.5 and 50 micrometers, and an oxide layer with the device layer being between the device wafer and the oxide layer and the oxide layer being between the device layer and the handle wafer, the device wafer having a boron concentration of at least about 1.times.10.sup.18 boron atoms/cm.sup.3 and a resistivity of about 0.01 to about 0.02 ohm-cm. A portion of the device wafer is mechanically removed from the silicon-on-insulator bonded substrate wherein the device wafer has a total thickness variation across the surface of the wafer of less than about 2 micrometers and a defect-free surface after the mechanical removal step.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: February 27, 1996
    Assignee: Si Bond L.L.C.
    Inventors: Subramanian S. Iyer, Emil Baran, Mark L. Mastroianni, Robert A. Craven
  • Patent number: 5488012
    Abstract: A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.
    Type: Grant
    Filed: October 18, 1993
    Date of Patent: January 30, 1996
    Assignee: The Regents of the University of California
    Inventor: Anthony M. McCarthy
  • Patent number: 5484738
    Abstract: A bonded, SOI wafer which has stepped isolation trenches and sublayer interconnections first formed in a bulk silicon wafer. After these process steps are complete, a thin polysilicon layer is formed on the planarized upper surface of the bulk silicon wafer. This thin polysilicon layer is then bound to an oxide layer on the surface of a separate wafer to form a bonded silicon-on-oxide structure. The entire assembly is, in effect inverted, and what had been the lower surface of the bulk silicon wafer, is removed to the bottom of the deepest trench step. In this bonded SOI structure, regions between the trenches are deep and suitable for bipolar device fabrication, while the trench steps form shallow regions suitable for fabrication of CMOS devices.
    Type: Grant
    Filed: March 1, 1995
    Date of Patent: January 16, 1996
    Assignee: International business Machines Corporation
    Inventors: Shao-Fu S. Chu, Chang-Ming Hsieh, Louis L. C. Hsu, Kyong-Min Kim, Shaw-Ning Mei
  • Patent number: 5484073
    Abstract: A method for fabricating a connecting spring member (24) of an arbitrary shape extending between a central mass (21) and an outer support frame (23) of a sensor as shown in FIG. 7 is disclosed. Each of a pair of generally identical silicon wafers (10, 12) has an inner etch stop layer (16) applied to one face with an outer epitaxial layer (18) formed over such etch stop layer (16). A photosensitive oxide layer (30) is applied to the other face of each of the wafers (10, 12). Next, a pattern of the central mass (21) and outer support frame (23) as shown in FIG. 2 is photographically imposed on the photosensitive oxide layers (18) of each wafer (10, 12). After wet chemical etching of the wafers (10, 12) removes silicon material to the etch stop layer, and the etch stop layer is itself removed in the space between the mass and the frame, the two wafers (10, 12) are bonded to each other as shown in FIG. 5 .
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: January 16, 1996
    Assignee: I/O Sensors, Inc.
    Inventor: Raymond K. Erickson
  • Patent number: 5484745
    Abstract: A method for forming at least one corrugation member in a semiconductor material, contains the step of: forming a semiconductor material layer onto a substrate, masking a first surface of the semiconductor material, etching the first surface to form first cavity thereon, removing a mask from the semiconductor material, masking the first surface and second surface of the semiconductor material, etching the second surface to form second cavity thereon, the second cavity being defined into the first cavity, removing the mask from the semiconductor material, depositing a specified masking material selected in accordance with a characteristic of the substrate onto the semiconductor material, etching an unmasked portion of the semiconductor material and depositing the same material as the abovementioned specified masking material selected in accordance with a characteristic of the substrate onto the semiconductor material and the specified masking material which has been deposited onto the semiconductor to form the
    Type: Grant
    Filed: October 26, 1993
    Date of Patent: January 16, 1996
    Assignee: Yazaki Meter Co., Ltd.
    Inventor: Sean S. Cahill
  • Patent number: 5482887
    Abstract: A method of manufacturing semiconductor devices with a passivated semiconductor body (1) provided with an electrode (2) and fastened on an electrically conducting support body (3), in which method a slice of semiconductor material (5) is fastened on a surface (6) of an electrically conducting auxiliary slice (7), and mesa structures (8) are formed in the slice of semiconductor material (5) by the application of grooves (9) in the slice of semiconductor material (5) subsequently, a layer of insulating material (10) is provided on the walls of the grooves (9), electrodes (2) are provided on upper sides (11) of the mesa structures (8), and the auxiliary slice (7) with the mesa structures (8) is split up at the areas of the grooves (9) into individual semiconductor bodies (1) each fastened on its own support body (3).
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: January 9, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Geert J. Duinkerken, Roelvinus M. M. Fonville
  • Patent number: 5478408
    Abstract: There is provided an SOI (Silicon On Insulator) substrate having a thick SOI layer, where crystallographic defects mainly consisting of OSFs (Oxidation Induced Stacking Fault) are practically prevented from occurrence in the SOI layer, according to the present invention.The manufacturing method for the SOI substrate according to the present invention comprises the following steps of: the silicon oxide film being formed by thermal oxidation on the surface of a first silicon wafer having a concentration of interstitial oxygen under 16 ppma (per JEIDA Standard); the first silicon wafer being superimposed on a second silicon wafer, which is a support for supporting the first silicon wafer, with the silicon oxide film sandwiched therebetween; then the superimposed wafers being heat-treated so as to obtain a bonded wafer; and further the bulk of the first silicon wafer of the bonded wafer being reduced by grinding and then polishing so as to obtain the SOI substrate with the SOI layer of more than 5 .mu.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: December 26, 1995
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Kiyoshi Mitani, Masatake Katayama, Kazushi Nakazawa
  • Patent number: 5478782
    Abstract: A wafer bonding method for forming a SOI structure comprising the steps of bringing wafers into proximity in a state with one wafer a slight, substantially uniform clearance away from the other wafer and pressing one point of at least one wafer of the two wafers against the other wafer. In another aspect of the invention, there is provided a method of positioning for photolithography using an alignment mark portions and/or a vernier portions formed on a SOI substrate, which comprises the step of removing semiconductor layer portions corresponding to the alignment mark portions and/or the vernier portions. In further another aspect of the invention, there is provided a new DRAM semiconductor device formed by using SOI structure, which comprises a new pattern of a strage node formed longitudinally along a word line. Further, there is provided a new DRAM semiconductor device formed by using SOI structure, which comprises a unique strage node having a conductive side wall.
    Type: Grant
    Filed: May 20, 1993
    Date of Patent: December 26, 1995
    Assignee: Sony Corporation
    Inventors: Hiroshi Satoh, Yasunori Ohokubo, Takeshi Matsushita, Toshiyuki Nishihara, Makoto Hashimoto
  • Patent number: 5476820
    Abstract: A semiconductor gas rate sensor includes a base composed of a first semiconductor substrate and a second semiconductor substrate bonded thereto by a thermosetting adhesive layer deposited on a mating surface of the second semiconductor substrate, the base having a gas flow passage defined therein and a nozzle defined therein for injecting a gas flow into the gas flow passage, and a detector disposed in and extending across the gas flow passage for detecting a deflected state of the gas flow when an angular velocity acts on the base, the nozzle being formed between a recess defined in mating surface of the first semiconductor substrate and the mating surface of the second semiconductor substrate.
    Type: Grant
    Filed: February 6, 1995
    Date of Patent: December 19, 1995
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Nobuhiro Fueki, Atsushi Inaba, Nariaki Kuriyama
  • Patent number: 5476813
    Abstract: In a method of manufacturing a bonded semiconductor substrate, a SiGe mixed crystal layer, a silicon layer containing N-type impurities, a SiGe mixed crystal layer containing N-type impurities of high concentration, and a silicon layer containing N-type impurities of high concentration are formed in this order on a top surface of a silicon substrate by an epitaxial growth process to form a first semiconductor substrate. A silicon oxide film is formed on a surface of a silicon substrate to form a second semiconductor substrate. The first and second semiconductor substrates are bonded to each other by heat treatment, with their top surfaces contacting each other. The first semiconductor substrate is etched from the back surface thereof until the SiGe mixed crystal layer is exposed, and the SiGe mixed crystal layer is etched until the silicon layer containing N-type impurities is exposed. This method prevents the thickness of the element forming layer from varying.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: December 19, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroshi Naruse
  • Patent number: 5476809
    Abstract: This invention relates to a semiconductor device which comprises a monocrystalline silicon substrate, a first insulating film formed in a first region on one major surface of the monocrystalline silicon substrate, a first monocrystalline silicon layer formed on the first insulating film, a second insulating film covering a side surface of the first monocrystalline silicon layer, a first polysilicon layer formed to cause a side surface of the first polysilicon layer to contact the second insulating film, and a second monocrystalline silicon layer, having a side surface contacts the first polysilicon layer, formed in a second region of the one major surface of the monocrystalline silicon substrate, and dielectrically isolated from the first monocrystalline silicon layer, and a method of manufacturing the same.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: December 19, 1995
    Assignee: NEC Corporation
    Inventor: Kenya Kobayashi
  • Patent number: 5474952
    Abstract: A process for producing a semiconductor service of the type having a semiconductor substrate; a semiconductor layer disposed on the semiconductor substrate; a first element formed in a region of the semiconductor layer and having a perimeter including a bottom; a second element formed in another region of the semiconductor layer; an insulating layer surrounding the perimeter of the first element, for electrically insulating and separating the first element from the second element and the semiconductor substrate; an electrical shield layer disposed between the insulating layer and the first element, surrounding the perimeter of the first element, and adapted to a reference electric potential applied thereto, for shielding the first element from an electrical fluctuation of the semiconductor substrate caused by the second element; and an electrode for applying the reference electric potential to the electrical shield layer.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: December 12, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventor: Tetsuo Fujii
  • Patent number: 5468674
    Abstract: A method for forming a semiconductor structure having a layer of low minority carrier lifetime and a layer of high minority carrier lifetime comprises the steps of forming a silicon dioxide layer on a layer of low minority carrier lifetime silicon of a silicon-on-sapphire handle wafer and another layer of silicon dioxide on a layer of high minority carrier lifetime silicon of a bulk silicon device wafer. The silicon dioxide layers are placed in contact and annealed to form a bonded structure having an annealed layer of silicon dioxide. The layer of bulk silicon is then thinned. The thinned layer of bulk silicon and the annealed silicon dioxide layer are patterned by photolithography to form mesas of high minority carrier lifetime silicon and to expose regions of low minority carrier lifetime silicon on the bonded structure.
    Type: Grant
    Filed: June 8, 1994
    Date of Patent: November 21, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Howard W. Walker, Graham A. Garcia
  • Patent number: 5466303
    Abstract: A semiconductor device, which can easily form hyper abrupt junction type junction having a desired depletion layer width or transition region width, is disclosed. A silicon oxide film is formed on the mirror polished side surface of a P-type semiconductor substrate. Then, a P-type diffusion layer is formed by means of heat treatment. In this process, impurity concentration distribution is formed in such a way that the impurity concentration distribution can abruptly decrease from the mirror polished side surface of the substrate. Following this, the oxide film is removed by etching, and hyper abrupt type PN junction is obtained by sticking the mirror polished side surface of a high impurity concentration N-type semiconductor substrate and the high impurity concentration diffusion side of the above P-type semiconductor substrate to each other in the same surface direction as that of the above P-type semiconductor substrate.
    Type: Grant
    Filed: March 24, 1995
    Date of Patent: November 14, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hitoshi Yamaguchi, Seiji Fujino, Tadashi Hattori
  • Patent number: 5466631
    Abstract: A method for producing a semiconductor article comprises the steps of preparing a first substrate having a non-porous semiconductor layer on a porous semiconductor region, forming unevenness on the surface at the side of said semiconductor layer of said first substrate; bonding the surface of said first substrate having said unevenness formed thereon to the surface of said second substrate so as to be in contact with each other, and removing said porous semiconductor under the state that said semiconductor layer is bonded to said second substrate to thereby transfer said semiconductor layer from said first substrate onto said second substrate.
    Type: Grant
    Filed: February 23, 1995
    Date of Patent: November 14, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeshi Ichikawa, Takao Yonehara, Masaru Sakamoto, Yasuhiro Naruse, Jun Nakayama, Kenji Yamagata, Kiyofumi Sakaguchi
  • Patent number: 5461001
    Abstract: A first semiconductor wafer having a semiconductor element such as a piezoresistive element or any integrated circuit located on a top surface thereof is bonded to a second semiconductor wafer so that the semiconductor element on the first wafer is received in a cavity sealed from the outside environment. The bottom surface of the second wafer is prepared by etching it about a mask pattern so that the pattern projects from the bottom surface, thereby forming the cavity and defining projecting surfaces which are bonded to corresponding projecting areas on the first wafer to create a hermetic seal therebetween. The second wafer is electrochemically etched to produce porous silicon with regions of non-porous monocrystalline silicon extending between the top and bottom surfaces. The porous areas are thermally oxidized to convert them to silicon dioxide while the non-porous regions bonded to bond pads of the resistive pattern on the first wafer act as extended contacts.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: October 24, 1995
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Joseph S. Shor, Alexander A. Ned
  • Patent number: 5459104
    Abstract: The invention relates to a process of production of a semiconductor substrate by binding etc. involving the direct polishing of an oxide film with step differences. A silicon oxide film (3) having step differences is formed on at least one surface of an active layer substrate (A). This silicon oxide film (3) is polished by a rigid platen using a polishing agent comprised primarily of cerium oxide. A support substrate (B) is laminated to the bonding face (3a) this obtained to obtain a wafer of a SOI structure. This enables elimination of the polycrystalline silicon layer on the silicon oxide film which had been formed only for bonding purposes.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: October 17, 1995
    Assignee: Mitsubishi Materials Silicon Corporation
    Inventor: Shinsuke Sakai
  • Patent number: 5455193
    Abstract: A silicon-on-insulator (SOI) material is formed from a bonded silicon wafer structure which includes, in order, a silicon handler substrate, an insulating oxide layer, a silicon device layer, a highly-doped silicon etch stop layer, and a top silicon substrate. The bonded silicon wafer structure is etched in a first anisotropic etching step to remove the top silicon substrate and expose the etch stop layer. Subsequently, a second anisotropic etching step is performed to remove a major portion but less than all of the etch stop layer, with the second anisotropic etching step continuing only until a substantially maximum degree of thickness uniformity is obtained in a remaining portion of the etch stop layer. The remaining portion of the etch stop layer is then removed, to yield a silicon-on-insulator material having a high degree of thickness uniformity.
    Type: Grant
    Filed: November 17, 1994
    Date of Patent: October 3, 1995
    Assignee: Philips Electronics North America Corporation
    Inventor: Richard H. Egloff
  • Patent number: 5455202
    Abstract: A microelectronic device is fabricated on a first substrate (40), and transferred to a second substrate (58). The first substrate (40) has a silicon etchable layer (42), a silicon dioxide etch-stop layer (44) overlying the etchable layer (42), and a single-crystal wafer (46) overlying the etch-stop layer (44). A microelectronic circuit element (48) is formed in the wafer (46) of the first substrate (40). The wafer (46) of the first substrate (40) is attached to an aluminum oxide temporary substrate (52), and the etchable layer (42) of the first substrate (40) is etched away down to the etch-stop layer (44) to leave a primary device structure. The etch-stop layer (44) may optionally be processed to remove all or a part of the layer. An exposed surface (56) of the primary device structure is fixed to the second substrate (58), and the temporary substrate (52) is removed.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: October 3, 1995
    Assignee: Hughes Aircraft Company
    Inventors: Gerard T. Malloy, Joseph J. Bendik
  • Patent number: 5453394
    Abstract: A process for preparing a semiconductor substrate comprises bringing a first substrate provided with at least one of boron and phosphorus on the surface of an insulating layer formed on the surface of the substrate in contact with a second substrate, and integrating both of the substrates by a heat treatment.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: September 26, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takao Yonehara, Kenji Yamagata
  • Patent number: 5451547
    Abstract: Disclosed is a method of manufacturing a semiconductor substrate by bonding two silicon crystalline wafers, and particularly, to a method of manufacturing a semiconductor substrate capable of reduced electrical resistance at the bonding interface. In the disclosed method, the silicon wafers to be bonded have at least one surface mirror-polished. Then they are washed, thus forming a natural oxide film on the surface. Then they are soaked in a concentrated HF solution for enough time to remove the oxide film formed on the surface. After that, the silicon wafers are soaked in ultra pure water to replace the fluorine atoms terminated on the surface thereof by OH groups, followed by drying. The silicon wafers thus treated are closely contacted with each other in such a manner that the mirror-polished surfaces are opposed to each other. The silicon wafers are thus bonded to each other by the hydrogen bonding forces due to the OH groups, and then heat treated for reinforcing the bonding.
    Type: Grant
    Filed: August 25, 1992
    Date of Patent: September 19, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hiroaki Himi, Masaki Matsui, Tosiaki Nisizawa, Seiji Fujino
  • Patent number: 5449638
    Abstract: A method for forming a thin, uniform top silicon layer using bonded-wafer SOI technology is described. A dielectric layer is formed on a first surface of a first silicon substrate. A trench is formed in a first surface of a second silicon substrate. A polishing stopper is formed in the trench. A second dielectric layer with a smooth top surface is formed over the polishing stopper and over the first surface of the second silicon substrate. The smooth top surface of the second dielectric layer of the second silicon substrate is bonded to the dielectric layer of the first silicon substrate. Material is removed from the exposed surface of the second silicon substrate to form the silicon layer with well-controlled thickness, having a top surface co-planar with the polishing stopper.
    Type: Grant
    Filed: June 6, 1994
    Date of Patent: September 12, 1995
    Assignee: United Microelectronics Corporation
    Inventors: Gary Hong, Chen-Chiu Hsue, H. J. Wu, Lawrence Y. Lin
  • Patent number: 5449659
    Abstract: A method for producing multilayer structures comprised of materials with incompatible processing parameters is disclosed. A bonding layer of arbitrary dielectric constant is applied to each of two substructures. Each substructure is composed of a substrate and at least one epitaxial crystalline layer. Examples of particular bonding materials used are polyimide, fluorocarbon polymers, other organic materials, and glass. The bonding material may be applied like photoresist, or sputtered, or applied in any appropriate manner consistent with the processing constraints of the crystalline materials. Structures formable in this way include superconductor-amorphous dielectric-superconductor and ferroelectric-insulator-semiconductor trilayers, as well as microwave resonators and multichip modules.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: September 12, 1995
    Assignee: Conductus, Inc.
    Inventors: Stephen M. Garrison, Randy W. Simon
  • Patent number: 5444014
    Abstract: Disclosed is a method of fabricating an SOI substrate, comprising the steps of forming a first insulating layer on a single crystal silicon substrate; patterning the first insulating layer to form an opening; growing a single crystal silicon in the opening to form active and inactive regions; polishing the active region 31 as the first insulating layer as a polishing stopper to form a planarized surface; depositing a second insulating layer on the planarized surface; bonding a bonding substrate to the second insulating layer; and polishing the silicon substrate using the first insulating layer as a stopper up to a surface of the active region. By the method, a stray capacitance occurring between an SOI substrate and a metal wiring portion formed thereon can be significantly reduced owing to a relatively thick insulating layer therebetween, and a parasitic capacitance can be eliminated owing to an insulating layer interposed between a bonding substrate and an active region to be used as a buried collector.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: August 22, 1995
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecommunication Authority
    Inventors: Byung-Ryul Ryum, Tae-Hyeon Han, Soo-Min Lee, Deok-Ho Cho, Seong-Hearn Lee, Jin-Young Kang
  • Patent number: 5443661
    Abstract: A silicon-on-insulator (SOI) substrate is arranged such that a polycrystalline silicon film which functions as a gettering site for heavy metals is provided on a first single crystal silicon substrate, a silicon oxide island film is partially provided in a polycrystalline silicon film, and a second single crystal silicon substrate is provided on an entire upper surface of the polycrystalline silicon film. An element isolation trench extends from an upper surface of the second single crystal silicon substrate to an upper surface of the first single crystal silicon substrate, and a silicon oxide film is buried in the element isolation trench. The SOI substrate thus constituted has a high gettering effect for heavy metals.
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: August 22, 1995
    Assignee: NEC Corporation
    Inventors: Shizuo Oguro, Tatsuya Suzuki
  • Patent number: 5441591
    Abstract: A method of bonding silicon to sapphire may be performed at room temperature and with no greater pressure than that due to one wafer resting on another. The method comprises the steps of polishing one side of a flat sapphire wafer to a mirror-like surface; polishing one side of a flat silicon wafer to a mirror-like surface; cleaning the wafers and then stacking the wafers so that their corresponding mirror-like surfaces contact. The room temperature bonding that occurs is relatively strong, and the bonded wafers can be handled without danger of their becoming unbonded. If desired, the bonded wafers may be subjected to further processing to further strengthen their bond.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: August 15, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: George P. Imthurn, Howard Walker
  • Patent number: 5441914
    Abstract: In one embodiment, delamination of a patterned silicon nitride anti-reflective layer (26) from an underlying patterned tungsten silicide layer (32), is prevented by forming a thin silicon layer (30) between the patterned tungsten silicide layer (32) and the overlying patterned silicon nitride anti-reflective layer (26).
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: August 15, 1995
    Assignee: Motorola Inc.
    Inventors: Robert C. Taft, Craig D. Gunderson, Arkalgud R. Sitaram
  • Patent number: 5437762
    Abstract: The invention concerns a method of forming various kinds of SOI structures and semiconductor memory devices using the forming technique. It is useful, for example, in SRAM or EEPROM devices. In EEPROM, it relates, in particular, to a method of manufacturing a non-volatile memory device in which a control gate electrode layer is laminated by way of an insulator film on a floating gate electrode layer. It includes a method of manufacturing a structure via the steps of forming an etching stopping layer on the surface of a silicon substrate, forming an epitaxially grown silicon layer on said etching stopping layer, bonding said silicon substrate formed with said silicon layer with another substrate as the insulator substrate, grinding said silicon substrate from the rear face and etching it until said etching stopping layer is exposed and removing said etching stopper layer, with or without polishing the other surface of said silicon substrate.
    Type: Grant
    Filed: July 13, 1994
    Date of Patent: August 1, 1995
    Assignee: Siemens Aktiengesellschaft
    Inventors: Akihiko Ochiai, Makoto Hashimoto, Takeshi Matsushita, Machio Yamagishi, Hiroshi Sato, Muneharu Shimanoe
  • Patent number: 5436173
    Abstract: A method for forming a semiconductor on insulator device is provided that begins with an outer semiconductor layer (16). Trenches (12) of a predetermined depth are formed in outer semiconductor layer (16). An insulator layer (20) is formed outwardly from outer semiconductor layer (16). A mesa (18a) having a predetermined thickness is formed by removing portions of outer semiconductor layer (16) to expose a working surface such that mesa (18a) has a thickness substantially equal to the predetermined depth of the trenches (12) after the working surface is exposed.
    Type: Grant
    Filed: January 4, 1993
    Date of Patent: July 25, 1995
    Assignee: Texas Instruments Incorporated
    Inventor: Theodore W. Houston
  • Patent number: 5420064
    Abstract: According to this invention, there is provided a method of manufacturing a semiconductor device, including the steps of anisotropically etching a surface of an n-type monocrystalline silicon substrate having the (100) plane to form a V-shaped isolation groove having a depth d.sub.1, performing ion implantation and performing annealing and diffusion to a surface of the V-shaped isolation groove to form an n.sup.+ -type buried layer, depositing a silicon dioxide film having a thickness d.sub.2 on a surface of the n.sup.+ -type buried layer, forming a polycrystalline silicon film on a surface of the silicon dioxide film, abrading and polishing the polycrystalline silicon film to have a thickness d.sub.3, adhering a monocrystalline silicon support substrate having a thickness d.sub.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: May 30, 1995
    Assignee: NEC Corporation
    Inventors: Kensuke Okonogi, Tsukasa Ohoka
  • Patent number: 5416044
    Abstract: A method for producing a surface-emitting laser, includes the steps of: forming a mask pattern to define a top mirror on a semiconductor substrate, the semiconductor substrate having a first semiconductor multilayer formed on the semiconductor substrate, a second semiconductor multilayer formed on the first semiconductor multilayer, and a third semiconductor multilayer formed on the second semiconductor multilayer, the first semiconductor multilayer constituting a bottom mirror, the second semiconductor layer including an upper barrier layer and a lower barrier layer, and an active layer sandwiched between the upper and lower barrier layers, the third semiconductor multilayer constituting a top mirror; forming the top mirror by partially removing the third semiconductor layer by dry etching using the mask pattern as a mask until the surface of the upper barrier layer of the second semiconductor multilayer is exposed; forming an etching protective film at least on the side of the top mirror; partially removing
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: May 16, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toyoji Chino, Kenichi Matsuda
  • Patent number: 5413952
    Abstract: A method for forming a direct wafer bonded structure having a buried high temperature metal nitride layer (16) and improved thermal conductivity is provided. By patterning the high temperature metal nitride layer (16) with a non-oxidizing photoresist stripper and absent a photoresist hardening step, adhesion between the high temperature metal nitride layer (16) and a dielectric layer (17, 27) subsequently formed over the high temperature metal nitride layer (16) is significantly improved. The dielectric layer (17, 27) will adhere to the high temperature metal nitride layer (16) in high temperature environments. In addition, a direct wafer bonded structure having a buried high temperature metal nitride layer (16) and improved thermal conductivity is provided. The structure is suitable for power, logic, and high frequency integrated circuit devices.
    Type: Grant
    Filed: February 2, 1994
    Date of Patent: May 9, 1995
    Assignee: Motorola, Inc.
    Inventors: Irenee Pages, Francesco D'Aragona, James A. Sellers, Raymond C. Wells
  • Patent number: 5407506
    Abstract: A method for enhancing the bond energy of reaction bonded surfaces in which polished (10) and cleaned surfaces (12) are bombarded with oxygen ions, fluorine ions or a mixture of oxygen and fluorine ions (14) to activate these surfaces. The activated surfaces are then cleaned to remove particulates (15) and then contacted (16) at room temperature to make a reaction bond therebetween. The reaction bond may be heated (18) to further increase the bond energy. The bond energy of oxygen ion bombarded surfaces can have two times the bond energy of surfaces subject to a conventional bonding process. The addition of fluorine ions to the oxygen ions used to activate the surfaces can further increase the bond energy between the contacted surfaces by at least another factor of 2.
    Type: Grant
    Filed: May 12, 1994
    Date of Patent: April 18, 1995
    Assignee: AlliedSignal Inc.
    Inventors: George G. Goetz, Warren M. Dawson
  • Patent number: 5407856
    Abstract: Disclosed is a process for producing a solid, surface bonding between two wafer plates, of which at least one is composed of a semiconducting material, such as e.g. silicon. The process has the following steps: on the cleaned surface of at least one wafer plate a film having a residual moisture from solvents containing silicates or phosphates is applied, the two wafer surfaces on at least one of which a film is applied are joined, the two wafers are tempered in the joined state at temperatures lower than approx. 420.degree. C.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: April 18, 1995
    Assignee: Fraunhofer Gesellschaft zur Forderung der angewandten Forschung
    Inventors: Hans J. Quenzer, Wolfgang Benecke
  • Patent number: 5403769
    Abstract: A process for producing a semiconductor device of the type having a semiconductor substrate; a semiconductor layer disposed on the semiconductor substrate; a first element formed in a region of the semiconductor layer and having a perimeter including a bottom; a second element formed in another region of the semiconductor layer; an insulating layer surrounding the perimeter of the first element, for electrically insulating and separating the first element from the second element and the semiconductor substrate; an electrical shield layer disposed between the insulating layer and the first element, surrounding the perimeter of the first element, and adapted to a reference electric potential applied thereto, for shielding the first element from an electrical fluctuation of the semiconductor substrate caused by the second element; and an electrode for applying the reference electric potential to the electrical shield layer.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: April 4, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventor: Tetsuo Fujii
  • Patent number: 5401665
    Abstract: A field-effect transistor in which a metal gate (14) is defined on top of an insulating substrate (12). A free-standing semiconductor thin film (16), obtained by the epitaxial lift-off process, is bonded to both the top of the metal gate and the insulating substrate. Electrodes (20, 22) attached to the top of ends of the semiconductor film complete the transistor.
    Type: Grant
    Filed: January 5, 1994
    Date of Patent: March 28, 1995
    Assignee: Bell Communications Research, Inc.
    Inventor: Winston K. Chan
  • Patent number: 5401672
    Abstract: A process wherein plurality of individual device layers having semiconductor material conductive regions extending therethrough are bonded together before or after one or more circuit elements have been fabricated on each layer. Groups of device layers are formed by electrochemically anodizing a wafer of semiconductor material. The wafer is rendered totally porous except for a series of non-porous regions extending therethrough. The wafer is then oxidized and densifted to result in a wafer having a plurality of electrically isolated extended contacts. A plurality of wafers are processed in this manner. A variety of integrated circuit devices are then formed on the surface of each wafer. Once the processing of all individual wafers is completed, each wafer is bonded to another, with the extending contact aligned to electrically interconnect each device layer. The wafers are then diced to provide a plurality of multi-level integrated circuit structures.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: March 28, 1995
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Alexander A. Ned
  • Patent number: 5395789
    Abstract: Integrated circuits are fabricated on a bonded wafer which has a buried silicide layer.
    Type: Grant
    Filed: August 6, 1993
    Date of Patent: March 7, 1995
    Assignee: AT&T Corp.
    Inventor: Bruce A. Beitman
  • Patent number: 5395481
    Abstract: A method by which single-crystal silicon microelectronics may be fabricated on glass substrates at unconventionally low temperatures. This is achieved by fabricating a thin film of silicon on glass and subsequently forming the doped components by a short wavelength (excimer) laser doping procedure and conventional patterning techniques. This method may include introducing a heavily boron doped etch stop layer on a silicon wafer using an excimer laser, which permits good control of the etch stop layer removal process. This method additionally includes dramatically reducing the remaining surface roughness of the silicon thin films after etching in the fabrication of silicon on insulator wafers by scanning an excimer laser across the surface of the silicon thin film causing surface melting, whereby the surface tension of the melt causes smoothing of the surface during recrystallization. Applications for this method include those requiring a transparent or insulating substrate, such as display manufacturing.
    Type: Grant
    Filed: October 18, 1993
    Date of Patent: March 7, 1995
    Assignee: Regents of the University of California
    Inventor: Anthony M. McCarthy