Combined With Formation Of Recessed Oxide By Localized Oxidation Patents (Class 438/425)
  • Patent number: 6518144
    Abstract: The elements and the trenches are arranged alternately, in repetition, on the main surface of a semiconductor substrate, each of the plurality of elements arranged alternately, in repetition, with the trenches has a configuration (for example, STM) which operates in the same operational mode, and an insulating layer, which is filled into the trenches, and doesn't have a void at a position (the position shallower than the broken line L) shallower than the pn junction to which the largest electric field in the element is applied. Thereby, a semiconductor device and a process for the same, where voids inside of the trenches can be reduced and the film thickness of the insulating film, for filling in the trenches which remain on the surface of the semiconductor substrate, can be made thinner, can be gained through a simple method.
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: February 11, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tetsuya Nitta, Tadaharu Minato
  • Publication number: 20030022460
    Abstract: A method of fabricating a semiconductor device in which a LOCOS profile characteristic is applied to a normal shallow trench isolation (STI) structure thereby lowering compressive stress that is concentrated on the side of the STI and preventing a thinning phenomenon by which the oxide film is formed in a relatively thin thickness at the boundary of the STI and the gate oxide film for high voltage (HV) region. The STI of a CVD oxide material including an angular bird's beak extension structure is formed in a field region, a gate oxide film is formed in a relatively thick thickness in a HV region by using a nitride film as a mask, and a gate oxide film having a relatively thin thickness is formed in a low voltage (LV) region.
    Type: Application
    Filed: April 8, 2002
    Publication date: January 30, 2003
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Joo-Han Park
  • Publication number: 20030006445
    Abstract: Gate structures, comprising a first insulation film, a first gate material and a gate oxide film, are formed. A second insulation film is formed on side surfaces of the gate structures in the peripheral region. Trenches are formed at a surface of the semiconductor substrate by etching the semiconductor substrate with the first and the second insulation films used as masks. The second insulation film formed on side surface of the gate structures is removed, exposing the surface of the semiconductor substrate in the vicinity of the gate structures on both sides of the trenches. Element-isolating insulation films are formed in the trenches and on the exposed substrate. The gate structures in the peripheral region are removed. Gate structures of peripheral transistors are formed between the element-isolating insulation films in the peripheral region.
    Type: Application
    Filed: July 2, 2002
    Publication date: January 9, 2003
    Inventor: Masahiko Kanda
  • Patent number: 6500729
    Abstract: A method for forming shallow trench isolation structures produces a shallow trench isolation structure having a substantially planar upper surface. The shallow trench isolation structure is formed from an originally formed shallow trench isolation structure which includes a deposited dielectric material within a trench and which exhibits dishing related problems in the form of a void formed within the trench, wherein the surface of the deposited dielectric material is recessed below the planar upper surface. The method provides for filling the void with a silicon film. The silicon film is then polished in its as-deposited or oxidized form, to produce a shallow trench isolation structure having a planar upper surface.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: December 31, 2002
    Assignee: Agere Systems Guardian Corp.
    Inventors: Sailesh Chittipeddi, Arun Kumar Nanda, Ankineedu Velaga
  • Patent number: 6498071
    Abstract: In the manufacture of a trench-gate semiconductor device, for example a MOSFET or an IGBT, a starting semiconductor body (10) has two top layers (13, 15) provided for forming the source and body regions. Gate material (11′) is provided in a trench (20) with a trench etchant mask (51, FIG. 2) still present so that the gate material (11′) forms a protruding step (30) from the adjacent surface (10a) of the semiconductor body, and a side wall spacer (32) is then formed in the step (30) to replace the mask (51). The source region (13) is formed self-aligned with the protruding trench-gate structure with a lateral extent determined by the spacer (32, FIG. 5), and the gate (11) is then provided with an insulating overlayer (18, FIG. 6).
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: December 24, 2002
    Assignee: Koninklijke Phillips Electronics N.V.
    Inventors: Erwin A. Hijzen, Cornelis E. Timmering, John R. Cutter
  • Patent number: 6495430
    Abstract: A process for fabricating a sharp corner-free shallow trench isolation structure. First, a SiON layer and a mask layer are successively formed on a semiconductor substrate. The SiON layer and mask layer are patterned to form an opening, exposing the substrate region on which a shallow trench isolation region will be formed. Next, an oxide spacer is formed on sidewalls of the SiON layer and mask layer. A trench is formed in the semiconductor substrate using the spacer and mask layer as a mask. Next, a liner oxide layer is formed on the surface of the trench by thermal oxidation, such that the liner oxide layer near the SiON layer is in a bird's beak form. An isolating oxide layer is filled in the trench. Finally, the mask layer and SiON layer are removed. The present invention forms a short and thick bird's beak structure and rounded trench corner. Therefore, the thickness of the tunnel oxide is even and the tunnel oxide integrity remains.
    Type: Grant
    Filed: May 21, 2002
    Date of Patent: December 17, 2002
    Assignee: Macronix International Co., Ltd.
    Inventors: Wen-Bin Tsai, Chun-Pei Wu, Hui-Huang Chen
  • Patent number: 6495898
    Abstract: In a combined isolation oxide film (BT1), a part closer to a gate electrode (GT13) reaches a buried oxide film (2) through an SOI layer (3) while a part closer to another gate electrode (GT12) has a sectional shape provided with a well region on its lower portion. The shape of an edge portion of the combined isolation oxide film (BT1) is in the form of a bird's beak in a LOCOS isolation oxide film. Consequently, the thicknesses of portions defining edge portions of the gate oxide films (GO12, GO13) are locally increased. Thus provided are a semiconductor device including a MOS transistor having a gate oxide film prevented from dielectric breakdown without increasing its thickness and a method of manufacturing the same.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: December 17, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Takuji Matsumoto
  • Publication number: 20020187616
    Abstract: A method of eliminating leakage current in shallow trench isolation is disclosed. After the trench is formed on the substrate, the liner oxide layer is formed in the furnace by introducing transdichloroethylene (TLC) into the furnace to round the corner of the trench. An electric filed near the rounded trench corner is decreased; thus, the leakage current produced in the corner of the shallow trench isolation is eliminated.
    Type: Application
    Filed: October 30, 2001
    Publication date: December 12, 2002
    Inventors: Chung-Ching Lai, Jui-Ping Li, Tung-Ming Lai, Chien-Nan Tu
  • Patent number: 6486039
    Abstract: A method of fabricating a trench isolation structure in a high-density semiconductor device that provides an isolation characteristic that is independent of the properties of adjacent MOS transistor devices, wherein a first trench in a first isolation area and a second trench implanted are formed on a semiconductor substrate, a nitrogen (N)-rich silicon layer is formed on the sidewall in a second isolation area, a subsequent oxidation process may be employed to fabricate oxide layers, each having a different thickness, on the sidewall surfaces of the first and second trenches. When the first and second oxide-layered trenches are filled with a stress relief liner and a dielectric material, the different thicknesses of the oxides prevent leakage currents from flowing to an adjacent semiconductor device, regardless of the doping properties of each device.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: November 26, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jae-yoon Yoo, Jeong-soo Lee, Nae-in Lee
  • Patent number: 6482718
    Abstract: A method of manufacturing a semiconductor device is provided which, even if device dimensions decrease, prevents degradation in the operating characteristics of semiconductor elements which are isolated from each other by an element isolation region in a trench isolation structure. Implantation of ions (15) in a polycrystalline silicon layer (3) from above through a silicon nitride film (2) produces an ion-implanted polycrystalline silicon layer (16). Since the ions (15) are an ionic species of element which acts to enhance oxidation, the implantation of the ions (15) changes the polycrystalline silicon layer (3) into the ion-implanted polycrystalline silicon layer (16) having a higher oxidation rate. In subsequent formation of a thermal oxide film (21) on the inner wall of a trench (5), exposed part of the ion-implanted polycrystalline silicon layer (16) is also oxidized, forming relatively wide polycrystalline silicon oxide areas (21a).
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: November 19, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Katsuomi Shiozawa, Takashi Kuroi, Katsuyuki Horita
  • Publication number: 20020167066
    Abstract: A semiconductor device having a trench isolation structure which has a high insulating characteristic, is suitable for miniaturizing a semiconductor device, and prevents a leakage current, as well as a method of manufacturing the semiconductor device. A small-density polysilicon film is formed between a semiconductor substrate and a CVD silicon oxide film in the area within a trench where a trench isolation structure is to be formed. Mechanical stress that develops between the semiconductor substrate and the CVD silicon oxide film during heat treatment is mitigated by changing the crystalline structure of the polysilicon film.
    Type: Application
    Filed: June 28, 2002
    Publication date: November 14, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shuuichi Ueno, Yasuo Inoue, Masayoshi Shirahata
  • Publication number: 20020167067
    Abstract: A trench isolation region is formed in a substrate by forming a trench-etching mask on the substrate. A trench is formed by etching the substrate through the trench-etching mask. An oxide layer is formed on sidewall and bottom surfaces of the trench. A liner layer is formed on the trench-etching mask and on the oxide layer. The liner layer is then removed at a boundary between the trench etching mask and the oxide layer so as to separate the liner layer into a first liner layer disposed on the trench etching mask and a second liner layer disposed on the oxide layer.
    Type: Application
    Filed: February 21, 2002
    Publication date: November 14, 2002
    Inventor: Min-Chul Kim
  • Patent number: 6479367
    Abstract: A method for forming an isolation layer in a semiconductor device, to avoid the occurrence of an angular formation phenomenon at the edge portions of the upper and lower portions of the trench during formation of a shallow trench isolation layer (STI), so that malfunction of the device and the deterioration of its performance due to a parasitic transistor and leakage current, can be prevented. Advantageously, silicon nitride films are formed at the side wall of the pad oxide film and the surface of trench silicon through a nitrogen (N+) plasma nitrification process, after a trench etching process, for formation of STI, so that the generation of a moat is inhibited and deterioration of the device is prevented.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: November 12, 2002
    Assignee: Hynix Semiconductor Inc.
    Inventor: Sang Wook Park
  • Patent number: 6468099
    Abstract: A method of fabricating a semiconductor device applies a LOCOS profile characteristic to an edge portion of an STI in a HV region to thereby lower compressive stress that is concentrated on the side of the STI. A field oxide film is formed so that only edge portions of HV region (active region II) may be in contact with a comparatively stiff STI, and then, a thick gate oxide film is formed on the HV region by utilizing a nitride film as a mask. After the nitride film as a mask is removed, a thin gate oxide film is formed on a LV region (an active region I in which a thin gate oxide film is formed). As a result, a thinning phenomenon of a gate oxide film at an edge portion of STI is prevented that otherwise would occur when the gate oxide film for HV grows in a normal STI structure by utilizing a nitride film as a mask.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: October 22, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Myoung-Soo Kim
  • Patent number: 6465324
    Abstract: A method is provided to form a LOCOS isolation in a CMOS SOI device. The SOI has a top silicon layer, a bottom silicon layer, and an insulation layer between the top and bottom silicon layers. An oxide layer is formed over the top silicon layer, and an LPCVD layer is deposited over the oxide layer. A photoresist is provided over the LPCVD layer that exposes a localized area of the LPCVD layer. The LPCVD layer and the oxide layer are etched away through the localized area to expose the top silicon layer. The silicon in the top silicon layer is etched so as to form a recess in the top silicon layer. The photoresist is removed and an isolation oxide is grown over the silicon in the recess so that the silicon in the recess is fully oxidized.
    Type: Grant
    Filed: March 23, 2001
    Date of Patent: October 15, 2002
    Assignee: Honeywell International Inc.
    Inventors: Eric E. Vogt, Cheisen J. Yue
  • Patent number: 6444540
    Abstract: First, a substrate, on which a plurality of semiconductor devices is formed, is provided. Next, a first etching treatment is carried out to the substrate with a first etching gas comprising CF4 to form a base trench having a rounded-off upper edge or tapered upper edge. A second etching treatment is carried out to the substrate to form a trench region at the base trench so that the trench region has a rounded-off upper edge. And then, an insulating layer is formed on the substrate to fill up the trench region therewith.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: September 3, 2002
    Assignee: Oki Electric Industry Co., LTD
    Inventors: Shinzi Kawada, Hiroyuki Kawano
  • Patent number: 6444539
    Abstract: A semiconductor apparatus and method for producing shallow trench isolation. The method includes the steps providing a semiconductor substrate member fabricated having a thin barrier oxide layer on which are fabricated a plurality of spaced apart silicon nitride pads. The regions between the spaced apart nitride pads delineate U-shaped regions for forming shallow isolation trenches and are layered with silicon oxide and polysilicon. The U-shaped regions provide a buffer region of oxide and polysilicon material adjacent opposing silicon nitride pads that prevent erosion of the nitride during etch formation of the isolation trench. The polysilicon is further etched to form a wider, second U-shaped region having sloped sidewalls that provide opposing spacer-forming buffer material that facilitates forming a V-shaped isolation trench region into the semiconductor substrate member a predetermined depth without eroding the silicon nitride pads.
    Type: Grant
    Filed: February 15, 2001
    Date of Patent: September 3, 2002
    Assignees: Advanced Micro Devices, Inc., Fujitsu Limited
    Inventors: Yu Sun, Angela T. Hui, Yue-Song He, Tatsuya Kajita, Mark Chang, Chi Chang, Hung-Sheng Chen
  • Patent number: 6440819
    Abstract: A local oxidation of silicon (LOCOS) process directed to forming differential field oxide thickness on a single wafer with minimized process steps and optimized planarity. When patterning the masking layer, at least two window widths are formed in the masking layer, exposing the underlying substrate and pad oxide. When one of the window widths is sufficiently small, oxidation of the substrate will be inhibited causing reduced growth and thus a reduced field oxide thickness in that window as compared to other larger windows formed in the same masking layer, creating differential field oxide thicknesses in one growth step. To optimize planarity, prior to oxidation variable depth trenches are formed in alignment with the windows so that the resulting field oxide regions are substantially planar with the substantial surface.
    Type: Grant
    Filed: March 3, 1998
    Date of Patent: August 27, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Scott Luning
  • Publication number: 20020106906
    Abstract: A structure comprising a trench having a liner with rounded corners in the top and bottom of the trench is obtained by rapid thermal oxidation.
    Type: Application
    Filed: December 13, 2000
    Publication date: August 8, 2002
    Applicant: International Business Machines Corporation
    Inventors: Arne W. Ballantine, Jeffrey S. Brown, Jeffrey D. Gilbert, James J. Quinlivan, James A. Slinkman, Anthony C. Speranza
  • Patent number: 6429092
    Abstract: A method for forming an oxide collar in a trench, in accordance with the present invention, includes forming a trench in a silicon substrate, and depositing and recessing a nitride liner in the trench to expose a portion of the silicon substrate on sidewalls of the trench. An oxide is deposited selective to the nitride liner on the portion of the silicon substrate. Residue oxide is removed from surfaces of the nitride liner to form a collar in the trench.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: August 6, 2002
    Assignee: Infineon Technologies AG
    Inventors: Jochen Beintner, Alexander Michaelis, Ulrike Gruening, Oswald Spindler, Zvonimir Gabric
  • Patent number: 6417050
    Abstract: A method of manufacturing a semiconductor component includes disposing a layer (120) of an electrically insulative material over a semiconductor substrate (110), etching a trench (310) into the layer and the semiconductor substrate, disposing a layer (410) of a semiconductor material in the trench, and forming a gate contact (1410) in the trench.
    Type: Grant
    Filed: August 7, 2000
    Date of Patent: July 9, 2002
    Assignee: Semiconductor Components Industries LLC
    Inventor: Yoshinori Saito
  • Publication number: 20020086497
    Abstract: Shallow trench isolation is improved by adding sacrificial sidewalls to the nitride mask, which are subsequently removed to allow gap fill oxide material to overlap the edges of the active region, preventing CMP-induced trenching at the edges of the active area.
    Type: Application
    Filed: December 6, 2001
    Publication date: July 4, 2002
    Inventor: Siang Ping Kwok
  • Patent number: 6406976
    Abstract: Semiconductor devices and processes for forming the same. The semiconductor device includes field isolation regions within trenches lying within a semiconductor device substrate. The trenches include a first trench and a second trench. The device includes a first component region and a second component region. The first component region lies near the first trench, and the second component region lies near the second trench. The semiconductor device includes a feature selected from a group consisting of: (a) a first liner within the first trench, and a second liner within the second trench, wherein the first liner is significantly thicker than the second liner; and (b) the first component region has a first edge with a first radius of curvature near the first trench, and the second component has a second edge with a second radius of curvature near the second trench, wherein the first radius of curvature is significantly greater than the second radius of curvature.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: June 18, 2002
    Assignee: Motorola, Inc.
    Inventors: Rana P. Singh, Chi Nan Brian Li
  • Patent number: 6403446
    Abstract: Manufacturing a semiconductor device avoiding an increase of transistor leak current or reduction of the withstanding voltage characteristics is by at least one of: The pad oxide film is removed along the substrate surface from the upper edge of the groove over a distance ranging from 5 to 40 nm: The exposed surface of the semiconductor substrate undergoes removal by isotropic etching within 20 nm; and oxidizing a groove portion formed in a semiconductor substrate in an oxidation environment with a gas ratio of hydrogen (H2) to oxygen (O2) being less than or equal to 0.5, an increase of the curvature radius beyond 3nm is achieved without associating the risk of creation of any level difference on the substrate surface at or near the upper groove edge portions in a groove separation structure.
    Type: Grant
    Filed: March 28, 2000
    Date of Patent: June 11, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ishitsuka, Hideo Miura, Shuji Ikeda, Yasuko Yoshida, Norio Suzuki, Masayuki Kojima, Kota Funayama
  • Patent number: 6399462
    Abstract: A method of forming a field oxide or isolation region in a semiconductor die. A nitride layer (over an oxide layer disposed over a substrate) is patterned and subsequently etched so that the nitride layer has a nearly vertical sidewall. The oxide layer and the substrate in the isolation region are etched to form a recess in the substrate having a sloped surface with respect to the nearly vertical sidewall of the nitride layer. A field oxide is then grown in the recess using a high pressure, dry oxidizing atmosphere. The sloped sidewall of the substrate effectively moves the face of the exposed substrate away from the edge of the nitride layer sidewall. Compared to non-sloped techniques, the oxidation appears to start with a built-in offset from the patterned etch. This leads to a reduction of oxide encroachment and a nearly non-existent bird's beak.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: June 4, 2002
    Assignee: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Sang S. Kim, Sharmin Sadoughi, Pamela Trammel, Avner Shelem
  • Patent number: 6372531
    Abstract: A plurality of photo diodes PD1 to PD4 are formed on a p-type silicon substrate. The photo diodes PD1 to PD4 are electrically isolated from one another by lower and upper isolation regions 3 and 5. Arms of strip portions of each of the lower and upper isolation regions 3 and 5 are narrowed in width toward the center of an intersection of the strip portions in a plane. Thereby, there can be provided a semiconductor device which can efficiently convert laser light for illumination to photovoltage.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: April 16, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hidenori Fujii
  • Patent number: 6372603
    Abstract: A method for forming a high performance photodiode with tightly-controlled junction profile for CMOS image sensor with STI process. The following steps are performed: providing a substrate; forming a hard mask layer for defining a pattern on the substrate; etching the substrate on the surface of the substrate not covered by the hard mask layer to form a shallow trench; growing an oxide lining in the shallow trench by a thermal oxidation process; performing a first thermal annealing; defining an n-well region in the shallow trench; implanting the n-well region; performing a second thermal annealing; forming a silicon oxide layer on the substrate to fill in the shallow trench; removing a portion of the silicon oxide layer on the substrate such that the portion in the shallow trench remains; removing the hard mask layer; and forming a transistor on the substrate, wherein the transistor comprises a gate structure, a source region, and a drain region.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: April 16, 2002
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Dun-Nian Yaung, Shou-Gwo Wuu, Chien-Hsien Tseng
  • Patent number: 6372602
    Abstract: The present invention provides a method of forming a shallow trench isolation structure in a substrate. The method comprises the steps of: forming an isolation silicon oxide film which comprises an upper portion extending over a silicon oxide film over a silicon nitride film and a lower portion extending in a trench in a silicon substrate; and carrying out an isotropic etching to said upper portion of said isolation silicon oxide film and said silicon oxide film, thereby forming an isolation trench structure without divots in said trench in said silicon substrate.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: April 16, 2002
    Assignee: NEC Corporation
    Inventor: Akira Mitsuiki
  • Patent number: 6372604
    Abstract: There is provided a method for forming a trench type element isolation structure wherein no recess develops in the edge part of an imbedded oxide film of a trench type element isolation. Thermal oxidation films having higher etching resistance than the CVD film are formed not only on the surroundings of the imbedded oxide film inside the groove formed on the silicon substrate but also on the lateral sides of the imbedded oxide film projecting upward from the silicon substrate surface.
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: April 16, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Maiko Sakai, Takashi Kuroi, Katsuyuki Horita
  • Patent number: 6368941
    Abstract: The present invention provides a method of fabricating a STI on a wafer to eliminate the common occurrence of junction leakage in the prior art. The method begins by forming a patterned hard mask on a silicon substrate. The patterned hard mask is a laminated layer comprising a pad oxide and a silicon nitride layer, and exposes a portion of the surface of the silicon substrate. The exposed portion of the silicon substrate is then dry etched to form a trench in the silicon substrate having a <100> surface and a <111> surface. Next, a portion of the pad oxide is wet etched around the STI corners of the trench to expose a portion of the top surface of the silicon substrate surrounding the periphery of the trench. A microwave-excited Kr/O2 plasma is used to oxidize both the interior surface of the trench and the exposed top surface of the silicon substrate located beneath the layer of silicon nitride surrounding the periphery of the trench at a temperature of 400° C.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: April 9, 2002
    Assignee: United Microelectronics Corp.
    Inventors: Tai-Ju Chen, Hua-Chou Tseng
  • Publication number: 20020034847
    Abstract: A self aligned method of forming a semiconductor memory array of floating gate memory cells in a semiconductor substrate having a plurality of spaced apart isolation regions and active regions on the substrate substantially parallel to one another in the column direction. Floating gates are formed in each of the active regions. In the row direction, trenches are formed that include indentations. The trenches are filled with a conducting material to form blocks of the conducting material that constitute control gates. The trench indentations result in the formation of protruding portions on the control gates that extend over the floating gates.
    Type: Application
    Filed: July 26, 2001
    Publication date: March 21, 2002
    Inventor: Chih Hsin Wang
  • Patent number: 6355974
    Abstract: A method to prevent the formation of a thinner portion of insulating layer, especially a gate oxide layer, at the junction between the side walls and the bottom insulator is disclosed. First, a pad oxide layer is formed on the side walls and the bottom of the trench. Next, a bottom oxide is formed on the lower portion of the trench. Then, the upper portion of the bottom oxide and the exposed pad oxide layer are removed by wet etching to leave a bottom oxide having a concave surface. Next, the conformal gate oxide layer is grown on the exposed side walls of the trench.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: March 12, 2002
    Assignee: Mosel Vitelic, Inc.
    Inventors: Ping-Wei Lin, Ming-Kuan Kao, Jui-Ping Li
  • Patent number: 6350659
    Abstract: A process for fabricating a silicon-on-insulator integrated circuit in conjunction with a process for shallow trench isolation is disclosed. The shallow trench isolation is performed to define active regions in the silicon substrate. The active regions are electrically isolated from each other by regions of silicon dioxide formed in the substrate by the shallow trench isolation process. The height of the silicon dioxide regions above the substrate surface defines the combined thickness of the islands of silicon dioxide and the silicon formed over the islands of silicon dioxide. A mask is then formed on the silicon substrate with the regions of silicon dioxide formed therein. The mask defines the regions on the silicon substrate surface on which the islands of silicon dioxide are to be formed. The silicon dioxide islands are formed with the mask in place, and the mask is subsequently removed. Single crystal silicon is formed epitaxially on the structure.
    Type: Grant
    Filed: September 1, 1999
    Date of Patent: February 26, 2002
    Assignee: Agere Systems Guardian Corp.
    Inventors: Chun-Ting Liu, Chien-Shing Pai
  • Patent number: 6348396
    Abstract: A semiconductor device having a SGI structure produced by selecting D, T and R values for satisfying the formula: D<0.4(−100R+7)−1(−230 T+14.5), wherein D is a width of an element formation region, T is a thermal oxidation amount of a groove in terms of microns, and R is a curvature radius at an end bottom portion of the groove, has excellent properties such as reduced in stress generated at bottom portions of grooves in a silicon substrate and not generating abnormal junction leakage current.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: February 19, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ishitsuka, Hideo Miura, Shuji Ikeda, Yasuko Yoshida
  • Publication number: 20020008298
    Abstract: A process for creating silicon isolation regions which utilizes silicon islands or pillars as sources of silicon for silicon dioxide (or silicon oxide) fields. These silicon oxide fields separate active areas within a device. By providing multiple sources of silicon for silicon oxide formation, the described invention minimizes the use of trench wall edges as silicon sources for silicon oxide growth. This reduction in stress helps to minimize encroachment and undergrowth or bird's beak formation. This process also leads to a reduced step height between the field oxide and active areas, thus providing a more planar wafer surface.
    Type: Application
    Filed: September 5, 2001
    Publication date: January 24, 2002
    Inventor: Salman Akram
  • Patent number: 6340624
    Abstract: A method of forming a circuitry isolation region within a semiconductive wafer comprises defining active area and isolation area over a semiconductive wafer. Semiconductive wafer material within the isolation area is wet etched using an etch chemistry which forms an isolation trench proximate the active area region having lowestmost corners within the trench which are rounded. Electrically insulating material is formed within the trench over the previously formed round corners. In accordance with another aspect, the semiconductive wafer material within the isolation area is etched using an etch chemistry which is substantially selective relative to semiconductive wafer material within the active area to form an isolation trench proximate the active area region. In accordance with still another aspect, a method of forming a circuitry isolation region within a semiconductive wafer comprises masking an active area region over a semiconductive wafer.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: January 22, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Trung Tri Doan, Mark Durcan
  • Patent number: 6339004
    Abstract: A method of forming a trench for semiconductor device isolation includes the steps of making a trench at a device isolation area of a silicon wafer by etching the silicon wafer and within through a mask pattern, forming a liner oxide on the silicon wafer with the trench through thermal oxidation, forming a nitride on the liner oxide through low pressure chemical vapor deposition, and anisotropically dry-etching the nitride such that the nitride is left only at the sidewalls of the trench. A trench-filling oxide is then deposited onto the entire surface of the silicon wafer through high pressure chemical vapor deposition, and annealed. The trench-filling oxide is planarized through chemical mechanical polishing until the top surface of the trench-filling oxide is positioned slightly over the liner oxide on the silicon wafer. The silicon wafer is then wet-cleaned, and thermally oxidized such that a pad oxide is grown at the surface of the silicon wafer.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: January 15, 2002
    Assignees: AnAm Semiconductor Inc., AmKor Technology, Inc.
    Inventor: Sang-Hyun Kim
  • Publication number: 20010055853
    Abstract: The present invention provides a process for fabricating a semiconductor device comprising the steps of: forming an etching-stop layer on a semiconductor substrate; patterning the etching-stop layer so that the etching-stop layer remains in a region to be an active region and is removed from a region to be a device isolation region, followed by forming a trench in the region to be the device isolation region; depositing on the semiconductor substrate an insulating film having a thickness greater than or equal to the depth of the trench; forming a resist pattern having an opening above the etching-stop layer above the active region adjacent to a device isolation region whose width is greater than or equal to a predetermined value, followed by etching the insulating film using the resist pattern as a mask; and polishing the insulating film existing on the resulting semiconductor substrate for flattening after removing the resist pattern.
    Type: Application
    Filed: December 2, 1998
    Publication date: December 27, 2001
    Inventors: TAKUJI TANIGAMI, KENJI HAKOZAKI, NAOYUKI SHINMURA, SHINICHI SATO, MASANORI YOSHIMI, TAKAYUKI TANIGUCHI
  • Patent number: 6333242
    Abstract: A method for fabricating a semiconductor device and a semiconductor formed by this method, the method including, the steps of sequentially forming a pad oxide film, a polysilicon film, and an antioxidation film on an active region of a semiconductor substrate such that a field region is exposed; etching an exposed portion of the surface of the substrate to a predetermined thickness to form a trench within the substrate; forming a first insulation film along the inner face of the trench by using an oxidation process; forming a stress buffer film on the entire surface of the resultant structure; forming a second insulation film on the stress buffer film such that the trench is sufficiently filled; making the second insulation film planar such that the remaining antioxidation film has a predetermined thickness on the active region of the substrate so as to form a shallow trench isolation within the trench; and sequentially removing the remaining antioxidation film, the polysilicon film, and the pad oxide film.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: December 25, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-Man Hwang, Hyung-Moo Park
  • Patent number: 6329266
    Abstract: A method of forming an isolation trench for an integrated circuit device includes forming a trench mask layer on a surface of a semiconductor substrate wherein a portion of the semiconductor substrate is exposed through the trench mask layer. An isolation trench is formed in the exposed portion of the semiconductor substrate, and a nitride liner is formed on surfaces of the isolation trench. A trench isolation layer is formed on the nitride liner wherein the trench isolation layer fills the trench, and the trench mask layer is damaged. The damaged trench mask layer is stripped so that the surface of the semiconductor substrate is exposed.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: December 11, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ki-Hyun Hwang, Seok-Woo Nam
  • Patent number: 6326255
    Abstract: A method for manufacturing a semiconductor device includes the steps of (1) forming a pad oxide film of 5 nm or more on a circuit forming surface of a semiconductor substrate; (2) forming an oxidation inhibition film on the pad oxide film; (3) forming grooves of a given depth with the oxidation inhibition film as a mask; (4) receding the pad oxide film; (5) oxidizing the grooves formed on the semiconductor substrate in the range of 0<C≦0.88t-924 in which the oxidizing atmosphere is dry oxidation (H2/O2≈0), the oxygen partial pressure in the air corresponding to the oxygen partial pressure ratio is C %, and the oxidizing temperature is t (° C.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: December 4, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ishitsuka, Hideo Miura, Shuji Ikeda, Yasuko Yoshida, Norio Suzuki, Michimasa Funabashi
  • Patent number: 6319795
    Abstract: A process for fabricating a VLSI device comprising trench isolation regions. The trench isolation regions of a VLSI device is fabricated by a process comprising the following steps: Depositing and patterning pad layers on a substrate to form active regions separated from pad-layer-covered regions; forming side walls at each active region to cover portions of the active region other than its central portion; depositing a first oxide at the space surrounded by the side walls and the central portion of the active region; removing the side walls to form trenches at the active region; and depositing a second oxide on the substrate to fill the trenches and cover the first oxide, the second oxide and the first oxide together forming an oxide trench isolation region.
    Type: Grant
    Filed: January 5, 2000
    Date of Patent: November 20, 2001
    Assignee: Mosel Vitelic Inc.
    Inventor: Jacson Liu
  • Publication number: 20010034109
    Abstract: A method of increasing trench density for semiconductor devices such as, for example, trench MOSFETs. Trenches are formed in a substrate with mesas interposed between the trenches. The initial width of the mesas are made less than target width so that a reduction in trench pitch can be realized. After a silicon layer is grown inside the trenches, the width of the mesas is increased to a final width that is two times the thickness of the silicon layer. The thickness of the silicon layer is precalculated so that it is of sufficient thickness to ensure compliance with the target mesa width.
    Type: Application
    Filed: May 1, 2001
    Publication date: October 25, 2001
    Inventors: Gordon K. Madson, Joelle Sharp
  • Patent number: 6306727
    Abstract: A process for creating silicon isolation regions which utilizes silicon islands or pillars as sources of silicon for silicon dioxide (or silicon oxide) fields. These silicon oxide fields separate active areas within a device. By providing multiple sources of silicon for silicon oxide formation, the described invention minimizes the use of trench wall edges as silicon sources for silicon oxide growth. This reduction in stress helps to minimize encroachment and undergrowth or bird's beak formation. This process also leads to a reduced step height between the field oxide and active areas, thus providing a more planar wafer surface.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: October 23, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Salman Akram
  • Patent number: 6303417
    Abstract: The present invention discloses a method of forming CMOS transistors with self-aligned planarization twin-well by using fewer mask counts. After a silicon nitride layer is formed over a first pad oxide layer on a semiconductor substrate, an N-well region is defined by first implanting in the semiconductor substrate. After removing the first photoresist layer, a second ion implantation is performed to define a P-well region. Next, both the silicon nitride layer and the first pad oxide layer are removed. A high temperature long time anneal is done to form a deep twin-well. A plurality of LPD oxide trench isolation regions is formed to define an active area region. A second pad oxide layer is formed on the substrate. Finally, the standard processes can be employed for fabricating the CMOS transistors on the substrate.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: October 16, 2001
    Assignee: TSMC-Acer Semiconductor Manufacturing Corp.
    Inventor: Shye-Lin Wu
  • Patent number: 6300220
    Abstract: An isolation structure having both deep and shallow components is formed in a semiconductor workpiece by etching the workpiece to define raised precursor active device regions separated by sunken precursor isolation regions. An oxidation mask is formed to expose the precursor isolation regions, and the unmasked precursor isolation regions are exposed to oxidizing conditions to grow field oxides as the deep isolation component. Thermal growth of these field oxides creates topography which includes shallow recesses adjacent to the raised precursor active device regions. Deposition of conformal dielectric material such as high density plasma (HDP) deposited silicon oxide over the entire surface and within the recesses creates the shallow isolation component. Following planarization of the conformal dielectric material, fabrication of the device is completed by introducing conductivity-altering dopant into raised precursor active device regions.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: October 9, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Albert Bergemont
  • Patent number: 6297127
    Abstract: Shallow trench isolation is combined with optional deep trenches that are self-aligned with the shallow trenches, at the corners of the shallow trenches, and have a deep trench width that is controlled by the thickness of a temporary sidewall deposited in the interior of the shallow trench and is limited by the sidewall deposition thickness of the deep trench fill.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: October 2, 2001
    Assignee: International Business Machines Corporation
    Inventors: Bomy A. Chen, Liang-Kai Han, Robert Hannon, Jay G. Harrington, Herbert L. Ho, Hsing-Jen Wann
  • Patent number: 6291315
    Abstract: A semiconductor wafer in which black silicon does not form during trench etching even when side rinsing is carried out during a photolithography process. In an embedded oxide film interposed between first and second semiconductor wafers of a bonded SOI wafer, the film thickness of a peripheral part thereof is made greater than a predetermined thickness Dsio so that it functions as an oxide film for etching prevention. When side rinsing is carried out in a resist coating process to form an opening in an oxide film for masking use in trench etching, the oxide film for masking use at the periphery is also etched during formation of the opening. Due to over-etching at that time, the oxide film for etching prevention is etched by a film thickness d1. During trench etching also, the oxide film for etching prevention is etched by a film thickness d2.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: September 18, 2001
    Assignee: Denso Corporation
    Inventors: Yoshiaki Nakayama, Shoji Miura
  • Publication number: 20010021559
    Abstract: The present invention relates to a collector pin and a trench in an integrated circuit intended for high speed communication, and to a manufacturing method for these items. The collector pin is achieved by creating an area which is implantation damaged or made amorphous and at least partially doped (139) by means of ion implantation from an upper silicon surface comprised in a semiconductor structure (144) down to a depth lower than the depth of the surrounding field oxide (120), and that the semiconductor structure (144) is then heat treated.
    Type: Application
    Filed: May 14, 2001
    Publication date: September 13, 2001
    Applicant: Telefonaktiebolaget LM Ericsson
    Inventors: Hans Erik Norstrom, Sam-Hyo Hong, Bo Anders Lindgren, Torbjorn Larsson
  • Patent number: 6284625
    Abstract: A method for manufacturing a semiconductor device includes the steps of (1) forming a pad oxide film of 5 nm or more on a circuit forming surface of a semiconductor substrate; (2) forming an oxidation inhibition film on the pad oxide film; (3) forming grooves of a given depth with the oxidation inhibition film as a mask; (4) receding the pad oxide film; (5) oxidizing the grooves formed on the semiconductor substrate in the range of 0<C≦0.88t−924 in which the oxidizing atmosphere is dry oxidation (H2/O2≈0), the oxygen partial pressure in the air corresponding to the oxygen partial pressure ratio is C %, and the oxidizing temperature is t (° C.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: September 4, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ishitsuka, Hideo Miura, Shuji Ikeda, Yasuko Yoshida, Norio Suzuki, Michimasa Funabashi