US20170317071A1 - Fin diode with increased junction area - Google Patents

Fin diode with increased junction area Download PDF

Info

Publication number
US20170317071A1
US20170317071A1 US15/139,644 US201615139644A US2017317071A1 US 20170317071 A1 US20170317071 A1 US 20170317071A1 US 201615139644 A US201615139644 A US 201615139644A US 2017317071 A1 US2017317071 A1 US 2017317071A1
Authority
US
United States
Prior art keywords
fins
region
forming
diode
semiconductor substrate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US15/139,644
Other versions
US9793262B1 (en
Inventor
Kasun Anupama Punchihewa
Jagar Singh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
GlobalFoundries US Inc
Original Assignee
GlobalFoundries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GlobalFoundries Inc filed Critical GlobalFoundries Inc
Priority to US15/139,644 priority Critical patent/US9793262B1/en
Assigned to GLOBALFOUNDRIES INC. reassignment GLOBALFOUNDRIES INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: PUNCHIHEWA, KASUN ANUPAMA, SINGH, JAGAR
Priority to US15/686,523 priority patent/US10056368B2/en
Application granted granted Critical
Publication of US9793262B1 publication Critical patent/US9793262B1/en
Publication of US20170317071A1 publication Critical patent/US20170317071A1/en
Assigned to WILMINGTON TRUST, NATIONAL ASSOCIATION reassignment WILMINGTON TRUST, NATIONAL ASSOCIATION SECURITY AGREEMENT Assignors: GLOBALFOUNDRIES INC.
Assigned to GLOBALFOUNDRIES U.S. INC. reassignment GLOBALFOUNDRIES U.S. INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GLOBALFOUNDRIES INC.
Assigned to GLOBALFOUNDRIES INC. reassignment GLOBALFOUNDRIES INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: WILMINGTON TRUST, NATIONAL ASSOCIATION
Assigned to GLOBALFOUNDRIES U.S. INC. reassignment GLOBALFOUNDRIES U.S. INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: WILMINGTON TRUST, NATIONAL ASSOCIATION
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/04Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body
    • H01L27/06Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a non-repetitive configuration
    • H01L27/0611Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a non-repetitive configuration integrated circuits having a two-dimensional layout of components without a common active region
    • H01L27/0617Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a non-repetitive configuration integrated circuits having a two-dimensional layout of components without a common active region comprising components of the field-effect type
    • H01L27/0629Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a non-repetitive configuration integrated circuits having a two-dimensional layout of components without a common active region comprising components of the field-effect type in combination with diodes, or resistors, or capacitors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/26Bombardment with radiation
    • H01L21/263Bombardment with radiation with high-energy radiation
    • H01L21/265Bombardment with radiation with high-energy radiation producing ion implantation
    • H01L21/26506Bombardment with radiation with high-energy radiation producing ion implantation in group IV semiconductors
    • H01L21/26513Bombardment with radiation with high-energy radiation producing ion implantation in group IV semiconductors of electrically active species
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/70Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
    • H01L21/77Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate
    • H01L21/78Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices
    • H01L21/82Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components
    • H01L21/822Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components the substrate being a semiconductor, using silicon technology
    • H01L21/8232Field-effect technology
    • H01L21/8234MIS technology, i.e. integration processes of field effect transistors of the conductor-insulator-semiconductor type
    • H01L21/823431MIS technology, i.e. integration processes of field effect transistors of the conductor-insulator-semiconductor type with a particular manufacturing method of transistors with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/04Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body
    • H01L27/08Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including only semiconductor components of a single kind
    • H01L27/0814Diodes only
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/02Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/06Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
    • H01L29/0603Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions characterised by particular constructional design considerations, e.g. for preventing surface leakage, for controlling electric field concentration or for internal isolations regions
    • H01L29/0642Isolation within the component, i.e. internal isolation
    • H01L29/0649Dielectric regions, e.g. SiO2 regions, air gaps
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/02Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/06Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
    • H01L29/0657Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions characterised by the shape of the body
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007Multistep manufacturing processes
    • H01L29/66075Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66083Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by variation of the electric current supplied or the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched, e.g. two-terminal devices
    • H01L29/6609Diodes
    • H01L29/66136PN junction diodes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/86Types of semiconductor device ; Multistep manufacturing processes therefor controllable only by variation of the electric current supplied, or only the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched
    • H01L29/861Diodes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/70Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
    • H01L21/77Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate
    • H01L21/78Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices
    • H01L21/82Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components
    • H01L21/84Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components the substrate being other than a semiconductor body, e.g. being an insulating body
    • H01L21/845Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components the substrate being other than a semiconductor body, e.g. being an insulating body including field-effect transistors with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/12Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body
    • H01L27/1203Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body the substrate comprising an insulating body on a semiconductor body, e.g. SOI
    • H01L27/1211Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body the substrate comprising an insulating body on a semiconductor body, e.g. SOI combined with field-effect transistors with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET

Definitions

  • the present disclosure generally relates to the fabrication of semiconductor devices, and, more particularly, to a fin diode with increased junction area and methods for making same.
  • FETs field effect transistors
  • MOS metal-oxide-semiconductor
  • FETs field effect transistors
  • MOS metal-oxide-semiconductor
  • FETs field effect transistors
  • NMOS and PMOS transistors are provided that are typically operated in a switching mode. That is, these transistor devices exhibit a highly conductive state (on-state) and a high impedance state (off-state).
  • FETs may take a variety of forms and configurations. For example, among other configurations, FETs may be either so-called planar FET devices or three-dimensional (3D) devices, such as finFET devices.
  • a so-called finFET device has a three-dimensional (3D) structure.
  • a fin topology also provides the potential of increased density for diode devices.
  • the dopant implantation process can damage the tip portions of the fin, resulting in increased defects and reduced junction area.
  • the aspect ratio of the fins also makes it difficult to implant dopants on the lower portions of the fin, which also reduces the junction area.
  • the present disclosure is directed to various methods and resulting devices that may avoid, or at least reduce, the effects of one or more of the problems identified above.
  • a method includes forming a first plurality of fins having a first width in a first region of a semiconductor substrate.
  • a second plurality of fins having a second width greater than the first width is formed in a second region of a semiconductor substrate.
  • a doped region is formed in a surface portion of the second plurality of fins to define an anode region of a diode.
  • a junction is defined between the doped region and a cathode region of the second plurality of fins.
  • a first contact interfacing with the anode region is formed.
  • Another method includes forming a plurality of fins in a semiconductor substrate.
  • a doped region is formed in a surface portion of the plurality of fins and in a surface portion of the semiconductor substrate disposed between adjacent fins in the plurality of fins to define an anode region of a diode.
  • a junction is defined between the doped region and a cathode region of the plurality of fins.
  • a first contact interfacing with the anode region is formed.
  • One illustrative semiconductor diode includes, among other things, a plurality of fins defined in a semiconductor substrate.
  • a doped region is defined in a surface portion defined in the plurality of fins and in a surface portion of the semiconductor substrate disposed between adjacent fins in the plurality of fins to define an anode region of the diode.
  • a junction is defined between the doped region and a cathode region of the plurality of fins.
  • a first contact interfaces with the anode region.
  • FIGS. 1A-1J depict various methods disclosed herein of forming a fin diode device.
  • the present disclosure generally relates to various methods of forming a fin diode device with increased junction area.
  • the present method is applicable to a variety of devices, including, but not limited to, logic devices, memory devices, etc.
  • various illustrative embodiments of the methods and devices disclosed herein will now be described in more detail.
  • FIGS. 1A-1J illustrate various methods for forming an integrated circuit product 100 on a substrate 105 .
  • the product 100 includes a transistor region 110 and a diode region 115 .
  • FIGS. 1A-1J show a cross-sectional view perpendicular to a long axis of fins to be formed in the product 100 (i.e., in the gate width direction of transistors in the transistor region 110 ).
  • the substrate 105 may have a variety of configurations, such as the depicted bulk silicon configuration.
  • the substrate 105 may also have a silicon-on-insulator (SOI) configuration that includes a bulk silicon layer, a buried insulation layer and an active layer, wherein semi-conductor devices are formed in and above the active layer.
  • SOI silicon-on-insulator
  • the substrate 105 may be formed of silicon or silicon germanium or it may be made of materials other than silicon, such as germanium. Thus, the terms “substrate” or “semiconductor substrate” should be understood to cover all semiconducting materials and all forms of such materials.
  • the substrate 105 may have different layers. For example, the substrate 105 may include a process layer formed above a base layer.
  • a hard mask layer 120 is formed above the substrate 105 .
  • a first mandrel 125 having elements 130 with a first width 130 W is formed above the hard mask layer 120 in the transistor region 110
  • a second mandrel 135 having elements 140 with a second width 140 W is formed above the hard mask layer 120 in the diode region 115 .
  • the mandrels 125 , 135 may be formed by patterning an amorphous silicon layer.
  • a spacer layer 145 is formed above the mandrels 125 , 130 . The portions of the spacer layer 145 on the sidewalls of the elements 140 merge, in at least the region contacting the hard mask layer 120 .
  • FIG. 1B illustrates the product 100 after an anisotropic etch process was performed on the spacer layer 145 to define spacers 150 , 155 on the sidewalls of the elements 130 , 140 , respectively. Due to the merging of the spacer layer 145 proximate the elements 140 , the spacers 155 have a width 155 W approximately twice the width 150 W of the spacers 150 .
  • FIG. 1C illustrates the product 100 after an etch process was performed to remove the mandrels 125 , 135 .
  • FIG. 1D illustrates the product 100 after an etch process was performed to pattern the hard mask layer 120 using the spacers 150 , 155 as an etch mask.
  • FIG. 1E illustrates the product 100 after an anisotropic etch process was performed to define fins 160 in the transistor region 110 of the substrate 105 and fins 165 in the diode region 115 of the substrate 105 .
  • the fins 165 have a width 165 W that is approximately twice a width 160 W of the fins 160 .
  • the fins 165 have a pitch and a width that are approximately double that of the fins 160 .
  • Figure 1F illustrates the product 100 after one or more etch processes were performed to remove the remaining portions of the cap layer 120 and the spacers 150 , 155 .
  • the subsequent steps illustrate the processing of the diode region 115 . Separate processing may be performed to fabricate devices in the transistor region 110 with appropriate masking steps to separate the process flows for the regions 110 , 115 .
  • FIG. 1G illustrates the product 100 after an implantation process was performed to form a doped surface region 170 on the fins 165 .
  • the doped surface region 170 has the opposite dopant type as compared to the fins 165 , thereby creating a PN junction 175 at the interface between the doped surface region 170 and the fins 165 .
  • the doped surface region 170 may define an anode region of a diode device and the portions of the fins opposite the PN junction 175 define a cathode region of the diode device.
  • the implantation process may be a hot implantation process, where the implantation is performed at an elevated temperature (e.g., >150° C.).
  • the implant energy may be between about 0.3-2 kV (e.g., 0.6 kV) and the dose may be between about 1E15/cm 2 and 2E16/cm 2 (e.g., 2E15/cm 2 ).
  • FIG. 1H illustrates the product 100 after a plurality of processes was performed to define an isolation structure 185 between the fins 165 .
  • a deposition process was performed to deposit a dielectric material and an etch process was performed to recess the dielectric material to expose upper portions of the fins 165 .
  • These processes may also be performed to define similar isolation structures (not shown) in the transistor region 110 .
  • one or more liner layers e.g., silicon nitride, silicon dioxide or a stack thereof
  • Any such liners may be removed after the recessing of the dielectric material.
  • FIG. 1I illustrates the product 100 after a plurality of processes was performed to form a contact structure 190 (e.g., anode contact) interfacing with the doped surface region 170 .
  • the processes may include one or more deposition processes to form one or more conductive layers (e.g., barrier layers, seed layers, fill layers) that will be part of the contact structure 190 (layers not separately shown).
  • the conductive material may be planarized.
  • FIG. 1J illustrates the product 100 after a plurality of processes was performed to form a contact structure 195 (e.g., cathode contact) interfacing with an undoped region of the fins 165 .
  • the processes may include one or more deposition processes to form one or more conductive layers (e.g., barrier layers, seed layers, fill layers) that will be part of the contact structure 195 (layers not separately shown).
  • the conductive material may be planarized.
  • the processes to form the contact structures 190 , 195 may be integrated with the processes for forming gate electrodes or contacts in the transistor region 110 .
  • a gate insulation layer (not shown) (e.g., silicon dioxide, hafnium oxide or a high-k material) may be formed in both regions 110 and 115 , and the gate insulation layer may be selectively removed in the diode region 115 prior to forming the conductive material.
  • line type contact structures 190 , 195 are illustrated, in some embodiments, via or plug type contacts may be used.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Computer Hardware Design (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Toxicology (AREA)
  • Health & Medical Sciences (AREA)
  • Metal-Oxide And Bipolar Metal-Oxide Semiconductor Integrated Circuits (AREA)

Abstract

A method incudes forming a first plurality of fins having a first width in a first region of a semiconductor substrate. A second plurality of fins having a second width greater than the first width is formed in a second region of a semiconductor substrate. A doped region is formed in a surface portion of the second plurality of fins to define an anode region of a diode. A junction is defined between the doped region and a cathode region of the second plurality of fins. A first contact interfacing with the anode region is formed.

Description

    BACKGROUND OF THE INVENTION 1. Field of the Invention
  • The present disclosure generally relates to the fabrication of semiconductor devices, and, more particularly, to a fin diode with increased junction area and methods for making same.
  • 2. Description of the Related Art
  • In modern integrated circuits, such as microprocessors, storage devices and the like, a very large number of circuit elements, especially transistors, are provided and operated on a restricted chip area. Diodes are another common device found in many integrated circuits.
  • In integrated circuits fabricated using metal-oxide-semiconductor (MOS) technology, field effect transistors (FETs) (both NMOS and PMOS transistors) are provided that are typically operated in a switching mode. That is, these transistor devices exhibit a highly conductive state (on-state) and a high impedance state (off-state). FETs may take a variety of forms and configurations. For example, among other configurations, FETs may be either so-called planar FET devices or three-dimensional (3D) devices, such as finFET devices.
  • To improve the operating speed of FETs, and to increase the density of FETs on an integrated circuit device, device designers have greatly reduced the physical size of FETs over the years. More specifically, the channel length of FETs has been significantly decreased, which has resulted in improving the switching speed of FETs. A so-called finFET device has a three-dimensional (3D) structure.
  • A fin topology also provides the potential of increased density for diode devices. However, as fin sizes decrease, the dopant implantation process can damage the tip portions of the fin, resulting in increased defects and reduced junction area. The aspect ratio of the fins also makes it difficult to implant dopants on the lower portions of the fin, which also reduces the junction area.
  • The present disclosure is directed to various methods and resulting devices that may avoid, or at least reduce, the effects of one or more of the problems identified above.
  • SUMMARY OF THE INVENTION
  • The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an exhaustive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is discussed later.
  • Generally, the present disclosure is directed to various methods of forming semiconductor devices. A method includes forming a first plurality of fins having a first width in a first region of a semiconductor substrate. A second plurality of fins having a second width greater than the first width is formed in a second region of a semiconductor substrate. A doped region is formed in a surface portion of the second plurality of fins to define an anode region of a diode. A junction is defined between the doped region and a cathode region of the second plurality of fins. A first contact interfacing with the anode region is formed.
  • Another method includes forming a plurality of fins in a semiconductor substrate. A doped region is formed in a surface portion of the plurality of fins and in a surface portion of the semiconductor substrate disposed between adjacent fins in the plurality of fins to define an anode region of a diode. A junction is defined between the doped region and a cathode region of the plurality of fins. A first contact interfacing with the anode region is formed.
  • One illustrative semiconductor diode includes, among other things, a plurality of fins defined in a semiconductor substrate. A doped region is defined in a surface portion defined in the plurality of fins and in a surface portion of the semiconductor substrate disposed between adjacent fins in the plurality of fins to define an anode region of the diode. A junction is defined between the doped region and a cathode region of the plurality of fins. A first contact interfaces with the anode region.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • The disclosure may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements, and in which:
  • FIGS. 1A-1J depict various methods disclosed herein of forming a fin diode device.
  • While the subject matter disclosed herein is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
  • DETAILED DESCRIPTION
  • Various illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
  • The present subject matter will now be described with reference to the attached figures. Various structures, systems and devices are schematically depicted in the drawings for purposes of explanation only and so as to not obscure the present disclosure with details that are well known to those skilled in the art. Nevertheless, the attached drawings are included to describe and explain illustrative examples of the present disclosure. The words and phrases used herein should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art. No special definition of a term or phrase, i.e., a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. To the extent that a term or phrase is intended to have a special meaning, i.e., a meaning other than that understood by skilled artisans, such a special definition will be expressly set forth in the specification in a definitional manner that directly and unequivocally provides the special definition for the term or phrase.
  • The present disclosure generally relates to various methods of forming a fin diode device with increased junction area. As will be readily apparent to those skilled in the art upon a complete reading of the present application, the present method is applicable to a variety of devices, including, but not limited to, logic devices, memory devices, etc. With reference to the attached figures, various illustrative embodiments of the methods and devices disclosed herein will now be described in more detail.
  • FIGS. 1A-1J illustrate various methods for forming an integrated circuit product 100 on a substrate 105. The product 100 includes a transistor region 110 and a diode region 115. FIGS. 1A-1J show a cross-sectional view perpendicular to a long axis of fins to be formed in the product 100 (i.e., in the gate width direction of transistors in the transistor region 110). The substrate 105 may have a variety of configurations, such as the depicted bulk silicon configuration. The substrate 105 may also have a silicon-on-insulator (SOI) configuration that includes a bulk silicon layer, a buried insulation layer and an active layer, wherein semi-conductor devices are formed in and above the active layer. The substrate 105 may be formed of silicon or silicon germanium or it may be made of materials other than silicon, such as germanium. Thus, the terms “substrate” or “semiconductor substrate” should be understood to cover all semiconducting materials and all forms of such materials. The substrate 105 may have different layers. For example, the substrate 105 may include a process layer formed above a base layer.
  • As illustrated in FIG. 1A, a hard mask layer 120 is formed above the substrate 105. A first mandrel 125 having elements 130 with a first width 130W is formed above the hard mask layer 120 in the transistor region 110, and a second mandrel 135 having elements 140 with a second width 140W is formed above the hard mask layer 120 in the diode region 115. In some embodiments, the mandrels 125, 135 may be formed by patterning an amorphous silicon layer. A spacer layer 145 is formed above the mandrels 125, 130. The portions of the spacer layer 145 on the sidewalls of the elements 140 merge, in at least the region contacting the hard mask layer 120.
  • FIG. 1B illustrates the product 100 after an anisotropic etch process was performed on the spacer layer 145 to define spacers 150, 155 on the sidewalls of the elements 130, 140, respectively. Due to the merging of the spacer layer 145 proximate the elements 140, the spacers 155 have a width 155W approximately twice the width 150W of the spacers 150.
  • FIG. 1C illustrates the product 100 after an etch process was performed to remove the mandrels 125, 135.
  • FIG. 1D illustrates the product 100 after an etch process was performed to pattern the hard mask layer 120 using the spacers 150, 155 as an etch mask.
  • FIG. 1E illustrates the product 100 after an anisotropic etch process was performed to define fins 160 in the transistor region 110 of the substrate 105 and fins 165 in the diode region 115 of the substrate 105. The fins 165 have a width 165 W that is approximately twice a width 160W of the fins 160. Hence, as compared to the fins 160, the fins 165 have a pitch and a width that are approximately double that of the fins 160.
  • Figure 1F illustrates the product 100 after one or more etch processes were performed to remove the remaining portions of the cap layer 120 and the spacers 150, 155. For ease of illustration, only the diode region 115 is illustrated in FIG. 1F. The subsequent steps illustrate the processing of the diode region 115. Separate processing may be performed to fabricate devices in the transistor region 110 with appropriate masking steps to separate the process flows for the regions 110, 115.
  • FIG. 1G illustrates the product 100 after an implantation process was performed to form a doped surface region 170 on the fins 165. The doped surface region 170 has the opposite dopant type as compared to the fins 165, thereby creating a PN junction 175 at the interface between the doped surface region 170 and the fins 165. The doped surface region 170 may define an anode region of a diode device and the portions of the fins opposite the PN junction 175 define a cathode region of the diode device. Providing the fins 165 with increased width and pitch allows the implantation process to reach the lower portions of the fins 165 and the surface portions 180 of the substrate 105, thereby providing that the PN junction 175 spans multiple fins 165. In addition, the increased width reduces the likelihood that the portions of the doped surface region 170 in tip regions 165T of the fins 165 will merge, thereby reducing the junction area. In some embodiments, the implantation process may be a hot implantation process, where the implantation is performed at an elevated temperature (e.g., >150° C.). In one embodiment, the implant energy may be between about 0.3-2 kV (e.g., 0.6 kV) and the dose may be between about 1E15/cm2 and 2E16/cm2 (e.g., 2E15/cm2).
  • FIG. 1H illustrates the product 100 after a plurality of processes was performed to define an isolation structure 185 between the fins 165. A deposition process was performed to deposit a dielectric material and an etch process was performed to recess the dielectric material to expose upper portions of the fins 165. These processes may also be performed to define similar isolation structures (not shown) in the transistor region 110. In some embodiments, one or more liner layers (e.g., silicon nitride, silicon dioxide or a stack thereof) (not shown) may be formed above the fins 165 prior to forming the isolation structure 185. Any such liners may be removed after the recessing of the dielectric material.
  • FIG. 1I illustrates the product 100 after a plurality of processes was performed to form a contact structure 190 (e.g., anode contact) interfacing with the doped surface region 170. The processes may include one or more deposition processes to form one or more conductive layers (e.g., barrier layers, seed layers, fill layers) that will be part of the contact structure 190 (layers not separately shown). The conductive material may be planarized.
  • FIG. 1J illustrates the product 100 after a plurality of processes was performed to form a contact structure 195 (e.g., cathode contact) interfacing with an undoped region of the fins 165. The processes may include one or more deposition processes to form one or more conductive layers (e.g., barrier layers, seed layers, fill layers) that will be part of the contact structure 195 (layers not separately shown). The conductive material may be planarized.
  • The processes to form the contact structures 190, 195 may be integrated with the processes for forming gate electrodes or contacts in the transistor region 110. For example, if the processes are part of the gate electrode process, a gate insulation layer (not shown) (e.g., silicon dioxide, hafnium oxide or a high-k material) may be formed in both regions 110 and 115, and the gate insulation layer may be selectively removed in the diode region 115 prior to forming the conductive material.
  • Although line type contact structures 190, 195 are illustrated, in some embodiments, via or plug type contacts may be used.
  • The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. For example, the process steps set forth above may be performed in a different order. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Note that the use of terms, such as “first,” “second,” “third” or “fourth” to describe various processes or structures in this specification and in the attached claims is only used as a shorthand reference to such steps/structures and does not necessarily imply that such steps/structures are performed/formed in that ordered sequence. Of course, depending upon the exact claim language, an ordered sequence of such processes may or may not be required. Accordingly, the protection sought herein is as set forth in the claims below.

Claims (15)

1. A method, comprising:
forming a first plurality of fins having a first width in a first region of a semiconductor substrate;
forming a second plurality of fins having a second width greater than said first width in a second region of said semiconductor substrate;
performing an implantation process to form a doped region in a first surface portion of each of said second plurality of fins and in a second surface portion of said semiconductor substrate positioned between adjacent fins in said second plurality of fins to define an anode region of a diode, wherein a cathode region of said diode is defined by an inner portion of each of said second plurality of fins positioned below and contacting said first surface portion and a third portion of said semiconductor substrate positioned below and contacting said second surface portion, said cathode region is contiguous, said doped region is contiguous between said adjacent fins,_said anode region comprises a first dopant having a first conductivity type, said cathode region comprises a material having a second dopant having a second conductivity type opposite said first conductivity type, and a junction is defined between said anode region and said cathode region; and
forming a first contact interfacing with said anode region.
2. (canceled)
3. (canceled)
4. The method of claim 1, wherein said implantation process comprises a hot implantation process.
5. The method of claim 1, further comprising forming an isolation structure between adjacent fins of said second plurality of fins that exposes upper portions of said second plurality of fins.
6. The method of claim 5, further comprising forming said first contact on said exposed upper portions of said second plurality of fins.
7. The method of claim 1, further comprising forming a second contact interfacing with said cathode region.
8. The method of claim 1, wherein said first region comprises a transistor region, and said second region comprises a diode region.
9. A method, comprising:
forming a plurality of fins in a semiconductor substrate;
performing an implantation process to form a doped region in a first surface portion of each of said plurality of fins and in a second surface portion of said semiconductor substrate disposed between adjacent fins in said plurality of fins to define an anode region of a diode, wherein a cathode region of said diode is defined by an inner portion of each of said plurality of fins positioned below and contacting said first surface portion and a third portion of said semiconductor substrate positioned below and contacting said second surface portion, said cathode region is contiguous, said doped region is contiguous between said adjacent fins, said anode region comprises a first dopant having a first conductivity type and said cathode region comprises a material having a second dopant having a second conductivity type opposite said first conductivity type, and a junction is defined between said anode region and said cathode region; and
forming a first contact interfacing with said anode region.
10. (canceled)
11. The method of claim 9, wherein said implantation process comprises a hot implantation process.
12. The method of claim 9, further comprising forming an isolation structure between adjacent fins of said plurality of fins that exposes upper portions of said plurality of fins.
13. The method of claim 12, further comprising forming said first contact on said exposed upper portions of said plurality of fins.
14. The method of claim 9, further comprising forming a second contact interfacing with said cathode region.
15.-19. (canceled)
US15/139,644 2016-04-27 2016-04-27 Fin diode with increased junction area Expired - Fee Related US9793262B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US15/139,644 US9793262B1 (en) 2016-04-27 2016-04-27 Fin diode with increased junction area
US15/686,523 US10056368B2 (en) 2016-04-27 2017-08-25 Fin diode with increased junction area

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US15/139,644 US9793262B1 (en) 2016-04-27 2016-04-27 Fin diode with increased junction area

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US15/686,523 Division US10056368B2 (en) 2016-04-27 2017-08-25 Fin diode with increased junction area

Publications (2)

Publication Number Publication Date
US9793262B1 US9793262B1 (en) 2017-10-17
US20170317071A1 true US20170317071A1 (en) 2017-11-02

Family

ID=60021695

Family Applications (2)

Application Number Title Priority Date Filing Date
US15/139,644 Expired - Fee Related US9793262B1 (en) 2016-04-27 2016-04-27 Fin diode with increased junction area
US15/686,523 Active US10056368B2 (en) 2016-04-27 2017-08-25 Fin diode with increased junction area

Family Applications After (1)

Application Number Title Priority Date Filing Date
US15/686,523 Active US10056368B2 (en) 2016-04-27 2017-08-25 Fin diode with increased junction area

Country Status (1)

Country Link
US (2) US9793262B1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3052291B1 (en) * 2016-06-03 2018-11-23 Stmicroelectronics (Rousset) Sas METHOD FOR MANUFACTURING A DIODE NETWORK, IN PARTICULAR FOR A NONVOLATILE MEMORY, AND CORRESPONDING DEVICE.
US11462648B2 (en) * 2019-12-05 2022-10-04 Globalfoundries U.S. Inc. Fin-based Schottky diode for integrated circuit (IC) products and methods of making such a Schottky diode

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090085163A1 (en) * 2007-09-27 2009-04-02 Christian Russ Vertical diode using silicon formed by selective epitaxial growth
US20090280582A1 (en) * 2008-05-09 2009-11-12 Interuniversitair Microelektronica Centrum Design Methodology for MuGFET ESD Protection Devices
US20130285208A1 (en) * 2012-04-26 2013-10-31 International Business Machines Corporation Finfet diode with increased junction area
US20140124863A1 (en) * 2012-11-07 2014-05-08 International Business Machines Corporation Method and structure for forming a localized soi finfet
US9318621B2 (en) * 2013-03-08 2016-04-19 Taiwan Semiconductor Manufacturing Company, Ltd. Rotated STI diode on FinFET technology

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7560784B2 (en) * 2007-02-01 2009-07-14 International Business Machines Corporation Fin PIN diode
US8682116B2 (en) * 2007-08-08 2014-03-25 Infineon Technologies Ag Integrated circuit including non-planar structure and waveguide
KR101006527B1 (en) * 2008-11-10 2011-01-07 주식회사 하이닉스반도체 Phase change memory device and method for manufacturing the same
US8610241B1 (en) * 2012-06-12 2013-12-17 Taiwan Semiconductor Manufacturing Company, Ltd. Homo-junction diode structures using fin field effect transistor processing
US20140131831A1 (en) * 2012-11-12 2014-05-15 GlobalFoundries, Inc. Integrated ciruit including an fin-based diode and methods of its fabrication
TWI523084B (en) * 2014-11-11 2016-02-21 漢辰科技股份有限公司 Method for ion implantation
US9318622B1 (en) * 2015-06-23 2016-04-19 International Business Machines Corporation Fin-type PIN diode array
US9704966B1 (en) * 2016-07-25 2017-07-11 Globalfoundries Inc. Fin-based RF diodes
US9799647B1 (en) * 2016-08-22 2017-10-24 International Business Machines Corporation Integrated device with P-I-N diodes and vertical field effect transistors

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090085163A1 (en) * 2007-09-27 2009-04-02 Christian Russ Vertical diode using silicon formed by selective epitaxial growth
US20090280582A1 (en) * 2008-05-09 2009-11-12 Interuniversitair Microelektronica Centrum Design Methodology for MuGFET ESD Protection Devices
US20130285208A1 (en) * 2012-04-26 2013-10-31 International Business Machines Corporation Finfet diode with increased junction area
US20140124863A1 (en) * 2012-11-07 2014-05-08 International Business Machines Corporation Method and structure for forming a localized soi finfet
US9318621B2 (en) * 2013-03-08 2016-04-19 Taiwan Semiconductor Manufacturing Company, Ltd. Rotated STI diode on FinFET technology

Also Published As

Publication number Publication date
US20180006019A1 (en) 2018-01-04
US9793262B1 (en) 2017-10-17
US10056368B2 (en) 2018-08-21

Similar Documents

Publication Publication Date Title
US9064932B1 (en) Methods of forming gate structures by a gate-cut-last process and the resulting structures
US9882025B1 (en) Methods of simultaneously forming bottom and top spacers on a vertical transistor device
US20170125530A1 (en) Method of forming a gate contact structure for a semiconductor device
US11456382B2 (en) Transistor comprising an air gap positioned adjacent a gate electrode
US20180130895A1 (en) Methods of forming gate electrodes on a vertical transistor device
US9716177B2 (en) Semiconductor device comprising a multi-layer channel region
US9793294B1 (en) Junction formation with reduced Ceff for 22nm FDSOI devices
US10366930B1 (en) Self-aligned gate cut isolation
US10062772B2 (en) Preventing bridge formation between replacement gate and source/drain region through STI structure
US20190341468A1 (en) Method for forming and trimming gate cut structure
US10242982B2 (en) Method for forming a protection device having an inner contact spacer and the resulting devices
US10229999B2 (en) Methods of forming upper source/drain regions on a vertical transistor device
US9287130B1 (en) Method for single fin cuts using selective ion implants
US9502308B1 (en) Methods for forming transistor devices with different source/drain contact liners and the resulting devices
US10522410B2 (en) Performing concurrent diffusion break, gate and source/drain contact cut etch processes
US9711503B2 (en) Gate structures with protected end surfaces to eliminate or reduce unwanted EPI material growth
US10056368B2 (en) Fin diode with increased junction area
US9548249B2 (en) Methods of performing fin cut etch processes for FinFET semiconductor devices and the resulting devices
US10727133B2 (en) Method of forming gate structure with undercut region and resulting device
US10629500B2 (en) Product that includes a plurality of vertical transistors with a shared conductive gate plug
US10950692B2 (en) Methods of forming air gaps between source/drain contacts and the resulting devices
US9171922B1 (en) Combination finFET/ultra-thin body transistor structure and methods of making such structures
US20170288041A1 (en) Method for forming a doped region in a fin using a variable thickness spacer and the resulting device
US10600876B2 (en) Methods for chamfering work function material layers in gate cavities having varying widths
US10453754B1 (en) Diffused contact extension dopants in a transistor device

Legal Events

Date Code Title Description
AS Assignment

Owner name: GLOBALFOUNDRIES INC., CAYMAN ISLANDS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:PUNCHIHEWA, KASUN ANUPAMA;SINGH, JAGAR;REEL/FRAME:038393/0271

Effective date: 20160426

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: WILMINGTON TRUST, NATIONAL ASSOCIATION, DELAWARE

Free format text: SECURITY AGREEMENT;ASSIGNOR:GLOBALFOUNDRIES INC.;REEL/FRAME:049490/0001

Effective date: 20181127

AS Assignment

Owner name: GLOBALFOUNDRIES U.S. INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GLOBALFOUNDRIES INC.;REEL/FRAME:054633/0001

Effective date: 20201022

AS Assignment

Owner name: GLOBALFOUNDRIES INC., CAYMAN ISLANDS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:WILMINGTON TRUST, NATIONAL ASSOCIATION;REEL/FRAME:054636/0001

Effective date: 20201117

AS Assignment

Owner name: GLOBALFOUNDRIES U.S. INC., NEW YORK

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:WILMINGTON TRUST, NATIONAL ASSOCIATION;REEL/FRAME:056987/0001

Effective date: 20201117

FEPP Fee payment procedure

Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

LAPS Lapse for failure to pay maintenance fees

Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20211017