Forming Lateral Transistor Structure Patents (Class 438/316)
  • Patent number: 6767779
    Abstract: A structure and method for a field effect transistor capable of handling high currents, comprises interleaved source and drain diffusion regions with drain diffusion contacts to a first metal level over the drain diffusions only; while a second metal level covers the full width of the device and takes current out of the source in a primarily vertical direction.
    Type: Grant
    Filed: June 19, 2003
    Date of Patent: July 27, 2004
    Assignee: International Business Machines Corporation
    Inventors: Scott M. Parker, Steven J. Tanghe
  • Patent number: 6750105
    Abstract: A method for fabricating a high-voltage transistor with an extended drain region includes forming an epitaxial layer on a substrate, the epitaxial layer and the substrate being of a first conductivity type; then etching the epitaxial layer to form a pair of spaced-apart trenches that define first and second sidewall portions of the epitaxial layer. A dielectric layer is formed that partially fills each of the trenches, covering the first and second sidewall portions. The remaining portions of the trenches are then filled with a conductive material to form first and second field plate members that are insulated from the substrate and the epitaxial layer. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: June 15, 2004
    Assignee: Power Integrations, Inc.
    Inventor: Donald Ray Disney
  • Patent number: 6667213
    Abstract: A method for fabricating a high-voltage transistor with an extended drain region includes forming parallel arranged drift regions, each of which is interleaved with an insulating layer and a conducting layer that functions as a field plate. Source and body regions of opposite conductivity types are formed, with the body regions separating the source regions from the drift regions. An insulated gate is formed adjacent the body region. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure, It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: December 23, 2003
    Assignee: Power Integrations, Inc.
    Inventor: Donald Ray Disney
  • Patent number: 6638807
    Abstract: An improved structure and method for gated lateral bipolar transistors are provided. Embodiments of the present invention capitalize on opposing sidewalls and adjacent conductive sidewall members to conserve available surface space on the semiconductor chips. Additionally, the gate and body of the transistors are biased to modify the threshold voltage of the transistor (Vt). The conductive sidewall member configuration conserves surface space and achieves a higher density of surface structures per chip. The structures offer performance advantages from both metal-oxide semiconductor (MOS) and bipolar junction transistor (BJT) designs. The devices can be used in a variety of applications, digital and analog, wherever a more compact structure with low power consumption and fast response time is needed.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: October 28, 2003
    Assignee: Mircon Technology, Inc.
    Inventors: Leonard Forbes, Wendell P. Noble
  • Patent number: 6635544
    Abstract: A method for fabricating a high-voltage transistor with an extended drain region includes forming an epitaxial layer on a substrate, the epitaxial layer and the substrate being of a first conductivity type; then etching the epitaxial layer to form a pair of spaced-apart trenches that define first and second sidewall portions of the epitaxial layer. A dielectric layer Is formed that partially fills each of the trenches, covering the first and second sidewall portions. The remaining portions of the trenches are then filled with a conductive material to form first and second field plate members that are insulated from the substrate and the epitaxial layer.
    Type: Grant
    Filed: September 7, 2001
    Date of Patent: October 21, 2003
    Assignee: Power Intergrations, Inc.
    Inventor: Donald Ray Disney
  • Patent number: 6583007
    Abstract: A method for forming a non-volatile memory (NVM) device, the method including forming two diffusion areas in a substrate, said diffusion areas forming a channel therebetween, the channel being adapted to permit movement of primary electrons to at least one of the diffusion areas, forming a non-conducting charge trapping layer at least over the channel, and managing at least one of movement of secondary electrons from the substrate towards the charge trapping layer and a punch-through voltage in the substrate by controlling a position of a concentration of an electron acceptor dopant in the substrate.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: June 24, 2003
    Assignee: Saifun Semiconductors Ltd.
    Inventor: Boaz Eitan
  • Patent number: 6551869
    Abstract: A lateral PNP is disclosed in which a substrate of a first conductivity type is used. On top of the substrate a buried region of a second conductivity type is formed. A lightly doped collector region is located above the buried region. The lateral PNP also includes a base region of a second conductivity type formed by a graded channel implant and a well region of a second conductivity type, the well region contacting the base region, the buried region and a base contact. Additionally, there are collector contacts and emitter contacts of a first conductivity type. The lightly doped collector region results in a large Early voltage and the base region provides for a high current gain.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: April 22, 2003
    Assignee: Motorola, Inc.
    Inventors: Francis K. Chai, Vida Ilderem Burger, Carl S. Kyono, Sharanda L. Bigelow, Rainer Thoma
  • Patent number: 6548352
    Abstract: A multi-layered gate for use in a CMOS or CCD imager formed with a second gate at least partially overlapping it. The multi-layered gate is a complete gate stack having an insulating layer, a conductive layer, an optional silicide layer, and a second insulating layer, and has a second gate formed adjacent to it which has a second conductive layer that extends at least partially over the surface of the multi-layered gate. The multi-layered gate has improved insulation, thereby resulting in fewer shorts between the conductive layers of the two gates. Also disclosed are processes for forming the multi-layered gate and the overlapping gate.
    Type: Grant
    Filed: October 12, 2000
    Date of Patent: April 15, 2003
    Assignee: Micron Technology Inc.
    Inventor: Howard E. Rhodes
  • Patent number: 6541346
    Abstract: Disclosed is a manufacturing method to fabricate Heterojunction Bipolar Transistors (HBTs) that enables self-alignment of emitter and base metal contact layers with precise sub-micron spacing using a dielectric-assisted metal lift-off process. Such an HBT process relies on the formation of an “H-shaped” dielectric (i.e., Si3N4/SiO2) mask conformally deposited on top of the emitter contact metalization that is used to remove excess base metal through lift-off by a wet chemical HF-based etch. This HBT process also uses a thin selective etch-stop layer buried within the emitter layer to prevent wet chemical over-etching to the base and improves HBT reliability by forming a non-conducting, depleted ledge above the extrinsic base layer. The geometry of the self-aligned emitter and base metal contacts in the HBT insures conformal coverage of dielectric encapsulation films, preferably Si3N4 and/or SiO2, for reliable HBT emitter p-n junction passivation.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: April 1, 2003
    Inventor: Roger J. Malik
  • Patent number: 6528828
    Abstract: A differential negative resistance element includes a heavily doped GaAs layer interposed between a collector layer of lightly doped GaAs and an emitter layer of heavily doped AlGaAs, is shared between a base region between the collector layer and the emitter layer, a base contact region and a channel region between the base region and the base contact region, and a depletion layer is developed into the channel region together with the collector voltage so as to exhibit a differential negative resistance characteristics, wherein the channel region is formed through an epitaxial growth and etching so that the manufacturer easily imparts target differential negative resistance characteristics to the channel region.
    Type: Grant
    Filed: May 24, 2001
    Date of Patent: March 4, 2003
    Assignee: NEC Corporation
    Inventor: Tetsuya Uemura
  • Publication number: 20030040160
    Abstract: P-type LDMOS devices have been difficult to integrate with N-type LDMOS devices without adding an extra mask because the former have been unable to achieve the same breakdown voltage as the latter due to early punch-through. This problem has been overcome by preceding the epitaxial deposition of N− silicon onto the P− substrate with an additional process step in which a buried N+ layer is formed at the surface of the substrate by ion implantation. This N+ buried layer significantly reduces the width of the depletion layer that extends outwards from the P− well when voltage is applied to the drain thus substantially raising the punch-through voltage.
    Type: Application
    Filed: October 8, 2002
    Publication date: February 27, 2003
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY
    Inventors: Chih-Feng Huang, Kuo-Su Huang
  • Patent number: 6501152
    Abstract: A lateral NPN transistor (LPNP) (102) having the lightly doped drain extension implant blocked from the emitter region (118) but not the collector region (120). Accordingly, the emitter region (118) has a more abrupt junction for high emitter injection efficiency while the collector region (120) has a lightly doped region for reduced base depletion.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: December 31, 2002
    Assignee: Texas Instruments Incorporated
    Inventor: F. Scott Johnson
  • Publication number: 20020173108
    Abstract: A P-well and an N-well adjacent to the P-well are formed within a semiconductor substrate. A silicon nitride layer having an opening and a silicon oxide layer are then formed, respectively, on the semiconductor substrate. The silicon oxide layer fills the opening in the silicon nitride layer. Following that, a chemical mechanical polishing process removes portions of the silicon oxide layer to align the surface of the remaining silicon oxide layer with the surface of the silicon nitride layer to form an insulator. Subsequently, the silicon nitride layer is completely removed followed by forming a gate layer positioned on the P-well and N-well, a side of the gate layer being positioned on the surface of the insulator. Finally, an ion implantation process is performed to form N-type doping regions on the P-well and the N-well as a source and a drain of an LD MOS transistor, completing fabrication of the LD MOS transistor.
    Type: Application
    Filed: May 17, 2001
    Publication date: November 21, 2002
    Inventors: Ching-Chun Huang, Sheng-Hsiung Yang
  • Patent number: 6482710
    Abstract: A bipolar transistor according to the invention is provided with structure that an intrinsic base made of single crystal Si—Ge and a base leading-out electrode are connected via a link base made of polycrystal Si—Ge by doping at high concentration, further, a part immediately under the intrinsic base has the same conductive type as that of a collector and in a peripheral part, a single crystal Si—Ge layer having the same conductive type as that of a base is provided between the intrinsic base and a collector layer. Hereby, the reduction of the resistance of the link base between the intrinsic base and the base leading-out electrode and the reduction of capacitance between the collector and the base are simultaneously realized, and a self-aligned bipolar transistor wherein capacitance between an emitter and the base and capacitance between the collector and the base are respectively small, power consumption is small and high speed operation is enabled is acquired.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: November 19, 2002
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Katsuya Oda, Eiji Ohue, Masao Kondo, Katsuyoshi Washio, Masamichi Tanabe, Hiromi Shimamoto
  • Patent number: 6475870
    Abstract: P-type LDMOS devices have been difficult to integrate with N-type LDMOS devices without adding an extra mask because the former have been unable to achieve the same breakdown voltage as the latter due to early punch-through. This problem has been overcome by preceding the epitaxial deposition of N− silicon onto the P− substrate with an additional process step in which a buried N+ layer is formed at the surface of the substrate by ion implantation. This N+ buried layer significantly reduces the width of the depletion layer that extends outwards from the P− well when voltage is applied to the drain thus substantially raising the punch-through voltage.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: November 5, 2002
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Chih-Feng Huang, Kuo-Su Huang
  • Patent number: 6395607
    Abstract: A microelectronic device having a self aligned metal diffusion barrier is disclosed. A microelectronic device having a substrate and a dielectric layer on the substrate. A trench having inside walls is formed through the dielectric layer. A lining of a barrier metal is on the inside walls of the trench and a fill metal is in the trench between the linings on the inside walls of the trench. The fill metal and the barrier metal have substantially different removal selectivities. A covering of the barrier metal is on the fill metal and the covering spans the linings on the inside walls of the trench and conforms to the top of the fill metal in the trench.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: May 28, 2002
    Assignee: AlliedSignal Inc.
    Inventor: Henry Chung
  • Patent number: 6396124
    Abstract: The invention relates to a semiconductor device comprising a semiconductor body (10) including, for example, a p-type substrate (11) and a PNP bipolar transistor having a collector (1), a base (2) and an emitter (3), which are each provided with a connection conductor (7, 8, 9). One or more of the connection conductors (7, 8, 9) extend over a part of an insulating layer (20) which covers the body (10) which contains, below said insulating layer (20), a further semiconductor region (4) of a conductivity type opposite to that of the substrate (11). A disadvantage of the known device is that it is less suitable for certain applications, such as power amplification. In a device according to the invention, a sub-region (4b) of the further semiconductor region which borders on the substrate (11) is provided with a higher doping concentration than the remainder (4a) of the further semiconductor region (4).
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: May 28, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Hendrik Arend Visser
  • Patent number: 6380031
    Abstract: A method to form an embedded FLASH integrated circuit with reduced processing steps is described. In the method a partial etch is performed on the control gate region of a polycrystalline silicon film (21). A multiple etch process is then used to simultaneously form the FLASH memory cell gate stack (54), the NMOS gate structure (94) and the PMOS gate structure (96).
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: April 30, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Freidoon Mehrad, Jie Xia, Sandra Zheng, Lancy Tsung
  • Patent number: 6372586
    Abstract: A thick copper interconnection structure and method for an LDMOS transistor for power semiconductor devices. A large LDMOS transistor is formed of a plurality of source and drain diffusion regions to be coupled together to form the source and drain. Gate regions are formed between the alternating source and drain diffusions. Each diffusion region has a first metal layer stripe formed over it and in electrical contact with it. A second metal layer conductor is formed over a plurality of the first metal layer stripes, and selectively contacts the first metal layer stripes to form a source and a drain bus. A thick third metal layer is then formed over each second metal layer bus, either physically contacting it or selectively electrically contacting it. The thick third level metal is fabricated of a highly conductive copper layer.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: April 16, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Taylor R. Efland, Dave Cotton, Dale J. Skelton
  • Patent number: 6252274
    Abstract: A process of manufacturing cross-point matrix memory devices which have floating gate memory cells having the source channel self-aligned to the bit line and the field oxide is disclosed. The process includes the steps of growing a thin layer of tunnel oxide on the matrix region; depositing a stack structure comprising a first conductive layer, an intermediate dielectric layer, and a second conductive layer; photolithographing with a Polyl mask to define a plurality of parallel floating gate regions in the stack structure; self-aligned etching of the stack structure, above the active areas, to define continuous bit lines; and implanting, to confer predetermined conductivity on the active areas . Advantageously, the self-aligned cascade etching step for removing parallel strips from multiple layers, down to the active areas of the substrate, is discontinued before the field oxide is removed, and the implantation step is carried out in the presence of field oxide over the source active areas.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: June 26, 2001
    Assignee: STMicroelectronics S.r.L.
    Inventor: Elio Colabella
  • Patent number: 6146956
    Abstract: The invention relates to a process for making a lateral PNP bipolar electronic device integrated monolithically on a semiconductor substrate together with other bipolar devices of the NPN type, said device being incorporated to an electrically insulated multilayer structure. The device includes a semiconductor substrate doped with impurities of the P type; a first buried layer doped with impurities of the N type to form a base region; and a second layer, overlying the first and having conductivity of the N type, to form an active area with opposite collector and emitter regions being formed in said active area and separated by a base channel region. The width of the base channel region is defined essentially by a contact opening formed above an oxide layer deposited over the base channel region. Advantageously, the contact opening is formed by shifting an emitter mask.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: November 14, 2000
    Assignee: STMicroelectronics, S.r.l.
    Inventors: Angelo Pinto, Carlo Alemanni
  • Patent number: 6127236
    Abstract: A substantially concentric lateral bipolar transistor and the method of forming same. A base region is disposed about a periphery of an emitter region, and a collector region is disposed about a periphery of the base region to form the concentric lateral bipolar transistor of the invention. A gate overlies the substrate and at least a portion of the base region. At least one electrical contact is formed connecting the base and the gate, although a plurality of contacts may be formed. A further bipolar transistor is formed according to the following method of the invention. A base region is formed in a substrate and a gate region is formed overlying at least a portion of the base region. Emitter and collector terminals are formed on opposed sides of the base region. The gate is used as a mask during first and second ion implants.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: October 3, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Kirk D. Prall, Mike P. Violette
  • Patent number: 5949128
    Abstract: A bipolar transistor with MOS-controlled protection for a reverse-biased emitter-base junction is disclosed. A bipolar transistor and a MOS transistor are configured with the drain and the gate electrically coupled to the emitter, and the source and body electrically coupled to the base. A reverse-bias at the emitter-base junction, which is less than a breakdown voltage for the emitter-base junction, activates the MOS transistor which substantially reduces the resistance between the emitter and the base. Preferably, a first semiconductor region provides both the drain and the emitter, and a second semiconductor region provides both the body and the base, for reduced surface area on an integrated circuit chip.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: September 7, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Muhammed Ayman Shibib
  • Patent number: 5946582
    Abstract: A heterojunction bipolar transistor based on the InP/InGaAs materials family and its method of making. An n-type collector layer, principally composed of InP is epitaxially grown on an insulating InP substrate by vapor phase epitaxy. The collector layer is then laterally defined into a stack, and semi-insulating InP is regrown around the sides of the stack to the extent that it planarizes with the stack top. The semi-insulating InP electrically isolates the collector stack. A thin base layer of p-type InGaAs, preferably lattice matched to InP, is grown over the collector stack, and an n-type emitter layer is grown over the base layer. A series of photolithographic steps then defines a small emitter stack and a base that extends outside of the area of the emitter and collector stacks. The reduced size of the interface between the base and the collector produces a lower base-collector capacitance and hence higher speed of operation for the transistor.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: August 31, 1999
    Assignee: Telcordia Technologies, Inc.
    Inventor: Rajaram Bhat
  • Patent number: 5872034
    Abstract: A method of making an EPROM transistor in a high density CMOS integrated circuit having a poly to poly capacitor and including two layers of polysilicon. The EPROM transistor is made using only the steps used to make the other components of the high density CMOS integrated circuit. The EPROM transistor is programmable at the low voltages which high density CMOS transistors can handle.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: February 16, 1999
    Assignee: Delco Electronics Corporation
    Inventors: John Robert Schlais, Randy Alan Rusch
  • Patent number: 5728613
    Abstract: A process has been developed in which narrow base width, lateral bipolar junction transistors, and narrow channel length MOSFET devices, can be simultaneously fabricated, in a silicon on insulator layer. The narrow base width is defined by the width of an insulator sidewall spacer, formed on the sides of a polysilicon gate structure. The narrow base width, resulting in increased transistor gain and switching speed, along with reductions in parasitic capacitances, due to placing devices in a silicon on insulator layer, result in enhanced device performance.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: March 17, 1998
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Ching-Hsiang Hsu, Steve S. Chung, Shyh-Chyi Wong, Mong-Song Liang