Patents by Inventor Wensheng Wang

Wensheng Wang 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: 8349679
    Abstract: According to the present invention, a method of fabricating a semiconductor device is provided including forming a first interlayer insulating film 11, a crystalline conductive film 21, a first conductive film 23, a ferroelectric film 24 and a second conductive film 25 on a silicon substrate I in sequence, forming a conductive cover film 18 on the second conductive film 25, forming a hard mask 26a on the conductive cover film 18, forming a capacitor upon etching the conductive cover film 18, the second conductive film 25, the ferroelectric film 24 and the first conductive film 23 using the hard mask 26a as an etching mask in areas exposed from the hard mask 26a, and etching the hard mask 26a and the crystalline conductive film 21 exposed from the lower electrode 23a using an etching condition under which the hard mask 26a is etched.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: January 8, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Wensheng Wang
  • Publication number: 20130003256
    Abstract: A lower electrode film is formed above a substrate. A ferroelectric film is formed above the lower electrode film. An amorphous intermediate film of a perovskite-type conductive oxide is formed above the ferroelectric film. A first upper electrode film comprising oxide of at least one metal selected from a group of Pt, Pd, Rh, Ir, Ru, and Os is formed on the intermediate film. The intermediate film is crystallized by carrying out a first heat treatment in an atmosphere containing an oxidizing gas after the formation of the first upper electrode film. After the first heat treatment, a second upper electrode film comprising oxide of at least one metal selected from a group of Pt, Pd, Rh, Ir, Ru, and Os is formed on the first upper electrode film, at a temperature lower than the growth temperature for the first upper electrode film.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 3, 2013
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Patent number: 8344434
    Abstract: The present invention provides a method for manufacturing a semiconductor device, including the steps of: forming a first ferroelectric film on a first conductive film by a film-forming method including at least a step of forming a film by a sol-gel method; forming a second ferroelectric film on the first ferroelectric film by a sputtering method; forming a second conductive film on the second ferroelectric film; and forming a capacitor provided with a lower electrode, a capacitor dielectric film and an upper electrode by patterning the first conductive film, the first and second ferroelectric films and the second conductive film.
    Type: Grant
    Filed: May 4, 2011
    Date of Patent: January 1, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Wensheng Wang, Yoshimasa Horii
  • Patent number: 8338249
    Abstract: A method for manufacturing a semiconductor device comprises: forming a lower electrode on a semiconductor substrate, sputtering a ferroelectric film on the lower electrode using a target, thermal treating the ferroelectric film in an atmosphere containing oxygen in accordance with an accumulated period of use of the target for fabricating the ferroelectric film, and forming an upper electrode on the ferroelectric film.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: December 25, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Makoto Takahashi, Mitsushi Fujiki, Kenkichi Suezawa, Wensheng Wang, Ko Nakamura
  • Patent number: 8309999
    Abstract: The method includes the steps of forming an upper electrode of a capacitor by patterning a second conductive film; forming a capacitor dielectric film by patterning a ferroelectric film; and forming a lower electrode by patterning a first conductive film. A step of forming the first conductive film includes the steps of forming a lower conductive layer made of a noble metal other than iridium over a first interlayer insulating film; and forming an upper conductive layer made of a conductive material, which is different from a material for the lower conductive layer, and which is other than platinum.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: November 13, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Wensheng Wang
  • Publication number: 20120276659
    Abstract: An impurity-doped PZT film in an amorphous state doped with La, Ca, Sr, Si, Nb and/or the like is formed on a Pt film composing a bottom electrode film. Next, crystallization annealing for the impurity-doped PZT film is performed. Next, a PZT film is formed on the impurity-doped PZT film by an MOCVD method. Thereafter, an IrOX film, an IrOY film and an Ir film are formed on the PZT film.
    Type: Application
    Filed: July 10, 2012
    Publication date: November 1, 2012
    Applicant: Fujitsu Semiconductor Limited
    Inventors: Wensheng WANG, Masaki Kurasawa
  • Patent number: 8278181
    Abstract: A method for manufacturing a semiconductor device including a ferroelectric capacitor formed over a semiconductor substrate, wherein the ferroelectric capacitor including a lower electrode, a ferroelectric film formed on the lower electrode, and an upper electrode formed on the ferroelectric film, and the upper electrode including a first conductive film formed of a first conductive noble metal oxide, and a second conductive film formed of a metal nitride compound formed on the first conductive film.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: October 2, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Wensheng Wang
  • Publication number: 20120220057
    Abstract: Ferroelectric capacitors (42) are formed over a semiconductor substrate (10), then, a barrier film (46) directly covering the ferroelectric capacitors (42) is formed. Thereafter, wirings (56a etc.) connected to the ferroelectric capacitors (42) are formed. Further, a barrier film (58) is formed at a position higher than the wirings (56a etc.). In forming the barrier film (46), a film stack is formed, the film stack including at least two kinds of diffusion preventive films (46a and 46b) having different components and preventing diffusion of hydrogen or water.
    Type: Application
    Filed: May 10, 2012
    Publication date: August 30, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Patent number: 8236643
    Abstract: A method of manufacturing a semiconductor device with a ferroelectric capacitor, including, forming a lower insulating film on a semiconductor substrate, covering a MOS transistor, forming a lower electrode on the lower insulating film, forming a ferroelectric dielectric oxide film on the lower electrode, forming a first upper electrode on the dielectric oxide film, made of conductive oxide having a composition poor in oxygen, forming a second upper electrode on the first upper electrode, made of conductive oxide having a composition nearer to the stoichiometry, forming a third upper electrode on the second upper electrode, having a composition containing metal of the platinum group, constituting a ferroelectric capacitor, and forming a multilayer wiring structure above the lower interlevel insulating film, covering the ferroelectric capacitor, wherein the third upper electrode has a less oxygen composition than the first and second upper electrodes.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: August 7, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Wensheng Wang
  • Publication number: 20120181659
    Abstract: A ferroelectric capacitor formed above a semiconductor substrate includes a lower electrode, a dielectric film (ferroelectric film) having ferroelectric characteristics, and an upper electrode. The upper electrode includes a conductive oxide film made of a ferroelectric material to which conductivity is provided by adding a conductive material such as Ir, and the conductive oxide film is in contact with the dielectric film.
    Type: Application
    Filed: November 21, 2011
    Publication date: July 19, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng WANG
  • Publication number: 20120171785
    Abstract: There are provided a capacitor lower electrode formed on an adhesive layer, whose surface roughness is 0.79 nm or less, and having a (111) orientation that is inclined from a perpendicular direction to an upper surface of a substrate by 2.3° or less, a ferroelectric layer having a structure the (111) orientation of which is inclined from the perpendicular direction to the upper surface of the substrate by 3.5° or less, and a capacitor upper electrode.
    Type: Application
    Filed: March 12, 2012
    Publication date: July 5, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventors: Tomohiro Takamatsu, Junichi Watanabe, Ko Nakamura, Wensheng Wang, Naoyuki Sato, Aki Dote, Kenji Nomura, Yoshimasa Horii, Masaki Kurasawa, Kazuaki Takai
  • Publication number: 20120171784
    Abstract: A magnetron-sputtering film-forming apparatus includes: a vacuum film-forming chamber (11); electrostatic chuck units (12) for adjusting a temperature of the substrate (14); a target (15) for causing high-frequency magnetron sputtering; power supply units (17) for applying a discharge voltage between the substrate (14) and the target (15), and calculating an integral power consumption of an electricity discharged by the target (15); and control units (18) for controlling the electrostatic chuck units (12) and the power supply units (17). In the magnetron-sputtering film-forming apparatus, the temperature of the substrate to be processed (14) that is most suitable for sputtering is calculated based on the integral power consumption of the electricity discharged by the target (15) until that time, and the substrate (14) is adjusted to have a predetermined temperature to be subjected to the sputtering.
    Type: Application
    Filed: March 12, 2012
    Publication date: July 5, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Publication number: 20120107963
    Abstract: The present invention provides a semiconductor device which is characterized as follows. The semiconductor device includes: an interlayer insulating film formed above a semiconductor substrate and provided with a hole above an impurity diffusion region; a conductive plug formed in the hole and electrically connected to the impurity diffusion region; a conductive oxygen barrier film formed on the conductive plug and the interlayer insulating film around the conductive plug; a conductive anti-diffusion film formed on the conductive oxygen barrier film; and a capacitor that has a lower electrode which is formed on the conductive anti-diffusion film and which exposes platinum or palladium on the upper surface, a capacitor dielectric film made of a ferroelectric material, and an upper electrode. The conductive anti-diffusion film is made of a non-oxide conductive material for preventing the diffusion of the constituent element of the capacitor dielectric film.
    Type: Application
    Filed: January 4, 2012
    Publication date: May 3, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Publication number: 20120094398
    Abstract: In a semiconductor device manufacturing method, an amorphous or microcrystalline metal oxide film is formed over a first metal film which is preferentially oriented along a predetermined crystal plane. After that, a ferroelectric film is formed by a MOCVD method. When the ferroelectric film is formed, the metal oxide film formed over the first metal film is reduced to a second metal film and the ferroelectric film is formed over the second metal film. When the ferroelectric film is formed, the amorphous or microcrystalline metal oxide film is apt to be reduced uniformly. As a result, the second metal film the orientation of which is good is obtained and the ferroelectric film the orientation of which is good is formed over the second metal film. After the ferroelectric film is formed, an upper electrode is formed over the ferroelectric film.
    Type: Application
    Filed: December 21, 2011
    Publication date: April 19, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng WANG
  • Patent number: 8153448
    Abstract: There are provided a capacitor lower electrode formed on an adhesive layer, whose surface roughness is 0.79 nm or less, and having a (111) orientation that is inclined from a perpendicular direction to an upper surface of a substrate by 2.3° or less, a ferroelectric layer having a structure the (111) orientation of which is inclined from the perpendicular direction to the upper surface of the substrate by 3.5° or less, and a capacitor upper electrode.
    Type: Grant
    Filed: May 12, 2009
    Date of Patent: April 10, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Tomohiro Takamatsu, Junichi Watanabe, Ko Nakamura, Wensheng Wang, Naoyuki Sato, Aki Dote, Kenji Nomura, Yoshimasa Horii, Masaki Kurasawa, Kazuaki Takai
  • Publication number: 20120077288
    Abstract: According to the present invention, a method of fabricating a semiconductor device is provided including forming a first interlayer insulating film 11, a crystalline conductive film 21, a first conductive film 23, a ferroelectric film 24 and a second conductive film 25 on a silicon substrate I in sequence, forming a conductive cover film 18 on the second conductive film 25, forming a hard mask 26a on the conductive cover film 18, forming a capacitor upon etching the conductive cover film 18, the second conductive film 25, the ferroelectric film 24 and the first conductive film 23 using the hard mask 26a as an etching mask in areas exposed from the hard mask 26a, and etching the hard mask 26a and the crystalline conductive film 21 exposed from the lower electrode 23a using an etching condition under which the hard mask 26a is etched.
    Type: Application
    Filed: December 7, 2011
    Publication date: March 29, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Publication number: 20120032299
    Abstract: A method of manufacturing a semiconductor device includes forming an insulating film over a semiconductor substrate, forming a capacitor including a lower electrode, a capacitor dielectric film including a ferroelectric material, and an upper electrode over the insulating film, forming a first protective insulating film over a side surface and upper surface of the capacitor by a sputtering method, and forming a second protective insulating film over the first protective insulating film by an atomic layer deposition method.
    Type: Application
    Filed: May 16, 2011
    Publication date: February 9, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Publication number: 20120034712
    Abstract: A method for manufacturing a semiconductor device including a ferroelectric capacitor formed over a semiconductor substrate, wherein the ferroelectric capacitor including a lower electrode, a ferroelectric film formed on the lower electrode, and an upper electrode formed on the ferroelectric film, and the upper electrode including a first conductive film formed of a first conductive noble metal oxide, and a second conductive film formed of a metal nitride compound formed on the first conductive film.
    Type: Application
    Filed: October 25, 2011
    Publication date: February 9, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Publication number: 20120032300
    Abstract: A lower electrode film is formed above a substrate. A ferroelectric film is formed above the lower electrode film. An amorphous intermediate film of a perovskite-type conductive oxide is formed above the ferroelectric film. A first upper electrode film comprising oxide of at least one metal selected from a group of Pt, Pd, Rh, Ir, Ru, and Os is formed on the intermediate film. The intermediate film is crystallized by carrying out a first heat treatment in an atmosphere containing an oxidizing gas after the formation of the first upper electrode film. After the first heat treatment, a second upper electrode film comprising oxide of at least one metal selected from a group of Pt, Pd, Rh, Ir, Ru, and Os is formed on the first upper electrode film, at a temperature lower than the growth temperature for the first upper electrode film.
    Type: Application
    Filed: May 18, 2011
    Publication date: February 9, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventor: Wensheng Wang
  • Patent number: 8110411
    Abstract: The present invention provides a semiconductor device which is characterized as follows. The semiconductor device includes: an interlayer insulating film formed above a semiconductor substrate and provided with a hole above an impurity diffusion region; a conductive plug formed in the hole and electrically connected to the impurity diffusion region; a conductive oxygen barrier film formed on the conductive plug and the interlayer insulating film around the conductive plug; a conductive anti-diffusion film formed on the conductive oxygen barrier film; and a capacitor that has a lower electrode which is formed on the conductive anti-diffusion film and which exposes platinum or palladium on the upper surface, a capacitor dielectric film made of a ferroelectric material, and an upper electrode. The conductive anti-diffusion film is made of a non-oxide conductive material for preventing the diffusion of the constituent element of the capacitor dielectric film.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: February 7, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Wensheng Wang