Patents by Inventor Yongjun Jeff Hu

Yongjun Jeff Hu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7368796
    Abstract: A semiconductor device, such as a CMOS device, having gates with a high work function in PMOS regions and low work functions in NMOS regions and a method of producing the same. Using nitrogen implantation or plasma annealing, a low work function W (or CoSix)/TaSixNy/GOx/Si gate stack is formed in the NMOS regions while a high work function W (or CoSix)/Ta5Si3/GOx/Si gate stack is formed in the PMOS regions. The improved process also eliminates the need for a nitrided GOx which is known to degrade gm (transconductance) performance. The materials of the semiconductor devices exhibit improved adhesion characteristics to adjacent materials and low internal stress.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: May 6, 2008
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 7282443
    Abstract: The invention includes methods of forming metal silicide having bulk resistance of less than 30 micro-ohms-centimeter. The metal of the metal silicide can be selected from Groups 3, 4, 8, 9 and 10 of the periodic table, with an exemplary metal being titanium. An exemplary method includes forming a titanium-containing layer directly against tantalum silicide. After the titanium-containing layer is formed directly against the tantalum silicide, titanium of the titanium-containing layer is converted to titanium silicide. Constructions formed in accordance with methodology of the present invention can be incorporated into circuitry associated with semiconductor devices, such as, for example, wordlines and bitlines.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: October 16, 2007
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 7256138
    Abstract: An etching method for use in integrated circuit fabrication includes providing a metal nitride layer on a substrate assembly, providing regions of cobalt silicide on first portions of the metal nitride layer, and providing regions of cobalt on second portions of the metal nitride layer. The regions of cobalt and the second portions of the metal nitride layer are removed with at least one solution including a mineral acid and a peroxide. The mineral acid may be selected from the group including HCl, H2SO4, H3PO4, HNO3, and dilute HF (preferably the mineral acid is HCl) and the peroxide may be hydrogen peroxide. Further, the removal of the regions of cobalt and the second portions of the metal nitride layer may include a one step process or a two step process. In the one step process, the regions of cobalt and the second portions of the metal nitride layer are removed with a single solution including the mineral acid and the peroxide.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: August 14, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Whonchee Lee, Yongjun Jeff Hu
  • Patent number: 7211200
    Abstract: Metal nitride and metal oxynitride extrusions often form on metal silicides. These extrusions can cause short circuits and degrade processing yields. The present invention discloses a method of selectively removing such extrusions. In one embodiment, a novel wet etch comprising an oxidizing agent and a chelating agent selectively removes the extrusions from a wordline in a memory array. In another embodiment, the wet etch includes a base that adjusts the pH of the etch to selectively remove certain extrusions relative to other substances in the wordline. Accordingly, new metal silicide structures can be used to form novel wordlines and other types of integrated circuits.
    Type: Grant
    Filed: February 18, 2003
    Date of Patent: May 1, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Gary Chen, Li Li, Yongjun Jeff Hu
  • Patent number: 7109115
    Abstract: Various embodiments of the invention described herein reduce contact resistance to a silicon-containing material using a first refractory metal material overlying the silicon-containing material and a second refractory metal material overlying the first refractory metal material. Each refractory metal material is a conductive material containing a refractory metal and an impurity. The first refractory metal material is a metal-rich material, containing a level of its impurity at less than a stoichiometric level. The second refractory metal material has a lower affinity for the impurities than does the first refractory metal material. The second refractory metal material can thus serve as an impurity donor during an anneal or other exposure to heat.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: September 19, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Ravi Iyer, Yongjun Jeff Hu, Luan Tran, Brent Gilgen
  • Patent number: 7090815
    Abstract: A method of forming a catalyst body by forming a first layer of hemispherical grain polysilicon over a substrate, and oxidizing at least a portion of the first layer to form a second layer of silica. Additionally, forming a third layer of nitride material over the second layer, and forming a catalyst material over the nitride layer, can be performed before annealing to form a catalyst body.
    Type: Grant
    Filed: April 7, 2005
    Date of Patent: August 15, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Yongjun Jeff Hu, Er-Xuan Ping
  • Patent number: 7064390
    Abstract: A semiconductor device, such as a CMOS device, having gates with a high work function in PMOS regions and low work functions in NMOS regions and a method of producing the same. Using nitrogen implantation or plasma annealing, a low work function W (or CoSix)/TaSixNy/GOx/Si gate stack is formed in the NMOS regions while a high work function W (or CoSix)/Ta5Si3/GOx/Si gate stack is formed in the PMOS regions. The improved process also eliminates the need for a nitrided GOx which is known to degrade gm (transconductance) performance. The materials of the semiconductor devices exhibit improved adhesion characteristics to adjacent materials and low internal stress.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: June 20, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 7049231
    Abstract: In but one aspect of the invention, a method of depositing polysilicon comprises providing a substrate within a chemical vapor deposition reactor, with the substrate having an exposed substantially crystalline region and an exposed substantially amorphous region. A gaseous precursor comprising silicon is fed to the chemical vapor deposition reactor under conditions effective to substantially selectively deposit polysilicon on the crystalline region and not the amorphous region. In another aspect a method of fabricating a field effect transistor on a substrate comprises forming a gate dielectric layer and a gate over semiconductive material. Doped source/drain regions are formed within semiconductive material laterally proximate the gate. Substantially amorphous insulating material is formed over and laterally proximate the gate. The substrate is provided within a chemical vapor deposition reactor.
    Type: Grant
    Filed: June 7, 2004
    Date of Patent: May 23, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Michael Nuttall, Er-Xuan Ping, Yongjun Jeff Hu
  • Patent number: 7037829
    Abstract: Various embodiments of the invention described herein reduce contact resistance to a silicon-containing material using a first refractory metal material overlying the silicon-containing material and a second refractory metal material overlying the first refractory metal material. Each refractory metal material is a conductive material containing a refractory metal and an impurity. The first refractory metal material is a metal-rich material, containing a level of its impurity at less than a stoichiometric level. The second refractory metal material has a lower affinity for the impurities than does the first refractory metal material. The second refractory metal material can thus serve as an impurity donor during an anneal or other exposure to heat.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: May 2, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Ravi Iyer, Yongjun Jeff Hu, Luan Tran, Brent Gilgen
  • Patent number: 7038318
    Abstract: Various embodiments of the invention described herein reduce contact resistance to a silicon-containing material using a first refractory metal material overlying the silicon-containing material and a second refractory metal material overlying the first refractory metal material. Each refractory metal material is a conductive material containing a refractory metal and an impurity. The first refractory metal material is a metal-rich material, containing a level of its impurity at less than a stoichiometric level. The second refractory metal material has a lower affinity for the impurities than does the first refractory metal material. The second refractory metal material can thus serve as an impurity donor during an anneal or other exposure to heat.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: May 2, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Ravi Iyer, Yongjun Jeff Hu, Luan Tran, Brent Gilgen
  • Patent number: 7030014
    Abstract: The invention includes methods of forming metal silicide having bulk resistance of less than 30 micro-ohms-centimeter. The metal of the metal silicide can be selected from Groups 3, 4, 8, 9 and 10 of the periodic table, with an exemplary metal being titanium. An exemplary method includes forming a titanium-containing layer directly against tantalum silicide. After the titanium-containing layer is formed directly against the tantalum silicide, titanium of the titanium-containing layer is converted to titanium silicide. Constructions formed in accordance with methodology of the present invention can be incorporated into circuitry associated with semiconductor devices, such as, for example, wordlines and bitlines.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: April 18, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 6951636
    Abstract: A method of forming a catalyst body by forming a first layer of hemispherical grain polysilicon over a substrate, and oxidizing at least a portion of the first layer to form a second layer of silica. Additionally, forming a third layer of nitride material over the second layer, and forming a catalyst material over the nitride layer, can be performed before annealing to form a catalyst body.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: October 4, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Yongjun Jeff Hu, Er-Xuan Ping
  • Patent number: 6951786
    Abstract: The invention encompasses methods of forming silicide interconnects over silicon comprising substrates. In one implementation, a first layer comprising a metal and a non-metal impurity is formed over a region of a silicon comprising substrate where a silicide interconnection is desired. An elemental metal comprising second layer is formed over the first layer. The substrate is annealed to cause a reaction between at least the elemental metal of the second layer and silicon of the substrate region to form a silicide of the elemental metal of the second layer. In another considered aspect, a method of forming a silicide interconnect over a silicon comprising substrate includes providing a buffering layer to silicon diffusion between a refractory metal comprising layer and a silicon containing region of a substrate.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: October 4, 2005
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 6933580
    Abstract: Metal nitride and metal oxynitride extrusions often form on metal silicides. These extrusions can cause short circuits and degrade processing yields. The present invention discloses a method of selectively removing such extrusions. In one embodiment, a novel wet etch comprising an oxidizing agent and a chelating agent selectively removes the extrusions from a wordline in a memory array. In another embodiment, the wet etch includes a base that adjusts the pH of the etch to selectively remove certain extrusions relative to other substances in the wordline. Accordingly, new metal silicide structures can be used to form novel wordlines and other types of integrated circuits.
    Type: Grant
    Filed: July 3, 2003
    Date of Patent: August 23, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Gary Chen, Li Li, Yongjun Jeff Hu
  • Patent number: 6930029
    Abstract: A method of preventing formation of titanium oxide within a semiconductor device structure during a high temperature treatment of the device structure includes forming a passivation layer to preclude formation of titanium oxide at a titanium/oxide interface of a semiconductor device structure. The method includes providing a substrate assembly including at least an oxide region and forming a layer of titanium over a surface of the oxide region. The oxide region surface is treated with a plasma comprising nitrogen prior to forming the titanium layer so as to form a passivation layer upon which the titanium layer is formed. A thermal treatment is performed on the substrate assembly with the passivation layer substantially inhibiting diffusion of oxygen from the oxide layer during the thermal treatment of the substrate assembly. Generally, the passivation layer comprises SixOyNz.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: August 16, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Zhongze Wang, Li Li, Yongjun Jeff Hu
  • Patent number: 6849544
    Abstract: A conductive structure for use in a semiconductor device includes a multilayer structure. A first layer includes a material containing silicon, e.g., polysilicon and silicon germanide. A barrier layer is formed over the first layer, with the barrier layer including metal silicide or metal silicide nitride. A top conductive layer is formed over the barrier layer. The top conductive layer can include metal or metal silicide. Selective oxidation can be performed to reduce the amount of oxidation of selected materials in a structure containing multiple layers, such as the multi-layer conductive structure. The selective oxidation is performed in a single-wafer rapid thermal processing system, in which a selected ambient, including hydrogen, is used to ensure low oxidation of a selected material, such as tungsten or a metal nitride.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: February 1, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Ronald A. Weimer, Yongjun Jeff Hu, Pai Hung Pan, Deepa Ratakonda, James Beck, Randhir P. S. Thakur
  • Publication number: 20040266153
    Abstract: The invention includes methods of forming metal silicide having bulk resistance of less than 30 micro-ohms-centimeter. The metal of the metal silicide can be selected from Groups 3, 4, 8, 9 and 10 of the periodic table, with an exemplary metal being titanium. An exemplary method includes forming a titanium-containing layer directly against tantalum silicide. After the titanium-containing layer is formed directly against the tantalum silicide, titanium of the titanium-containing layer is converted to titanium silicide. Constructions formed in accordance with methodology of the present invention can be incorporated into circuitry associated with semiconductor devices, such as, for example, wordlines and bitlines.
    Type: Application
    Filed: June 26, 2003
    Publication date: December 30, 2004
    Inventor: Yongjun Jeff Hu
  • Publication number: 20040266119
    Abstract: The invention includes methods of forming metal silicide having bulk resistance of less than 30 micro-ohms-centimeter. The metal of the metal silicide can be selected from Groups 3, 4, 8, 9 and 10 of the periodic table, with an exemplary metal being titanium. An exemplary method includes forming a titanium-containing layer directly against tantalum silicide. After the titanium-containing layer is formed directly against the tantalum silicide, titanium of the titanium-containing layer is converted to titanium silicide. Constructions formed in accordance with methodology of the present invention can be incorporated into circuitry associated with semiconductor devices, such as, for example, wordlines and bitlines.
    Type: Application
    Filed: July 6, 2004
    Publication date: December 30, 2004
    Inventor: Yongjun Jeff Hu
  • Patent number: 6831343
    Abstract: A semiconductor device, such as a CMOS device, having gates with a high work function in PMOS regions and low work functions in NMOS regions and a method of producing the same. Using nitrogen implantation or plasma annealing, a low work function W (or CoSix)/TaSixNy/GOx/Si gate stack is formed in the NMOS regions while a high work function W (or CoSix)/Ta5Si3/GOx/Si gate stack is formed in the PMOS regions. The improved process also eliminates the need for a nitrided GOx which is known to degrade gm (transconductance) performance. The materials of the semiconductor devices exhibit improved adhesion characteristics to adjacent materials and low internal stress.
    Type: Grant
    Filed: September 10, 2003
    Date of Patent: December 14, 2004
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu
  • Patent number: 6825113
    Abstract: Disclosed are structures and processes which are related to asymmetric, self-aligned silicidation in the fabrication of integrated circuits. A pre-anneal contact stack includes a silicon substrate, a metal source layer such as titanium-rich titanium nitride (TiNx), and a silicon layer. The metal nitride layer is deposited on the substrate by sputtering a target metal reactively in nitrogen and argon ambient. A N:Ar ratio is selected to deposit a uniform distribution of the metal nitride in an unsaturated mode (x<1) over the silicon substrate. The intermediate substrate structure is sintered to form a metal silicide. The silicidation of metal asymmetrically consumes less of the underlying silicon than the overlying silicon layer. The resulting structure is a mixed metal silicide/nitride layer which has a sufficient thickness to provide low sheet resistance without excessively consuming the underlying substrate.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: November 30, 2004
    Assignee: Micron Technology, Inc.
    Inventor: Yongjun Jeff Hu