Patents by Inventor Zhaohui Cheng

Zhaohui Cheng 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: 7218126
    Abstract: An apparatus for measuring a sample with a circuit pattern including at least a porous low-permittivity hydrogensilsesquioxane material or a material structurally or compositionally similar to the porous low-permittivity hydrogensilsesquioxane. The apparatus includes an electron beam optics unit which enables scanning of a primary electron beam onto the sample, a detector which detects a secondary electron or a reflected electron, an image processing unit which measures a desired portion of the sample irradiated with the primary electron beam based on an output signal of the detector, and a control unit which controls the irradiation energy and density of the primary electron beam onto the sample.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: May 15, 2007
    Assignees: Hitachi, Ltd., Hitachi High-Technologies Corporation
    Inventors: Zhaohui Cheng, Mari Nozoe
  • Publication number: 20070085005
    Abstract: In the present invention, the structure of an electrification control electrode is changed from a grid type to a slit type and thereby shadows are not formed when a wafer is irradiated with a beam. Further, a beam forming slit is disposed ahead of an electrification control slit, thus the electrification control slit is prevented from being irradiated with an electron beam for preliminary electrification, and thereby secondary electrons which disturb the control of the electrification are inhibited from being generated. The shape of the slit is designed so that the strength of an electron beam may gradually decrease toward both the ends of an electron beam irradiation region in the longitudinal direction thereof. Furthermore, a preliminary static eliminator to remove or reduce the unevenness in an electrification potential distribution which has undesirably been formed earlier is disposed.
    Type: Application
    Filed: June 9, 2006
    Publication date: April 19, 2007
    Inventors: Masaki Hasegawa, Hiroshi Makino, Hikaru Koyama, Zhaohui Cheng, Hisaya Murakoshi
  • Publication number: 20070040118
    Abstract: A inspecting and measurement method and inspecting and measurement apparatus for semiconductor devices and patterns such as photomasks using an electron beam which can measure the charged potential of a sample with higher precision than in the prior art, and a inspecting and measurement apparatus which can measure charged potential by means of a simple construction. When an S curve is observed in a semiconductor device to be inspectioned and measured, fluctuations of the charged potential of the inspection sample surface are suppressed by optimizing the energy of a primary electron beam used for irradiation. When the surface potential of the semiconductor device is measured, a more precise potential measurement than that of the prior art can be performed which is almost unaffected by the charged potential of an insulation film surface.
    Type: Application
    Filed: August 15, 2006
    Publication date: February 22, 2007
    Inventors: Zhaohui Cheng, Hiroshi Makino, Hikaru Koyama, Mitsugu Sato
  • Publication number: 20060163477
    Abstract: When the electrode potential of a charge control electrode above a wafer is reduced, image brightness is reduced. A point of change in the image brightness is a switching point between a positively charged state of the image and a negatively charged state of the image, showing the weakly charged state of the image. By setting this point of change as an inspecting condition, the amount of electric charges on the surface of the wafer can be reduced, and stable wafer inspection can be performed. It is estimated that an applied voltage V1 in FIG. 14 corresponds to the point of the change and is roughly included in the voltage range of a region enclosed by a broken line in the vicinity of the applied voltage V1. Within this voltage range, the influence of charge on an inspection under the inspecting condition can be reduced.
    Type: Application
    Filed: December 22, 2005
    Publication date: July 27, 2006
    Inventors: Mari Nozoe, Yasunori Goto, Zhaohui Cheng
  • Publication number: 20060151698
    Abstract: A charged particle beam apparatus is provided which has high resolving power and a wide scanning region (observation field of view). The apparatus has a unit for adjusting the focus, a unit for adjusting astigmatism, a unit for controlling and detecting scanning positions and a controller operative to control the focus adjustment and astigmatism adjustment at a time in interlocked relation to the scanning positions, thereby assuring compatibility between the high resolving power and the observation view field of a wide area.
    Type: Application
    Filed: December 20, 2005
    Publication date: July 13, 2006
    Inventors: Yuko Sasaki, Yasuhiro Gunji, Zhaohui Cheng
  • Publication number: 20060028218
    Abstract: An apparatus for measuring a sample with a circuit pattern including at least a porous low-permittivity hydrogensilsesquioxane material or a material structurally or compositionally similar to the porous low-permittivity hydrogensilsesquioxane. The apparatus includes an electron beam optics unit which enables scanning of a primary electron beam onto the sample, a detector which detects a secondary electron or a reflected electron, an image processing unit which measures a desired portion of the sample irradiated with the primary electron beam based on an output signal of the detector, and a control unit which controls the irradiation energy and density of the primary electron beam onto the sample.
    Type: Application
    Filed: September 6, 2005
    Publication date: February 9, 2006
    Inventors: Zhaohui Cheng, Mari Nozoe
  • Patent number: 6952105
    Abstract: A pattern inspecting technique, depending on the kind of materials, can reduce damage including shrinkage to materials when the materials are prone to such damage as shrinkage and spoilage caused by electron beam irradiation. This is accomplished by scanning a sample with a primary electron beam, detecting secondary electrons generated, or electrons reflected from the semiconductor device, or both the former and latter electrons, and converting the electrons into signals, and transforming the signals into an image, displaying the image, and detecting defective spots in the circuit pattern of the sample. The irradiation density (dose per unit area) of the electron beam is monitored and limited depending on the kind of material of the circuit pattern under inspection and the inspecting conditions, and damage, such as shrinkage and spoilage to the materials during electron beam irradiation, is reduced to an allowable range.
    Type: Grant
    Filed: July 17, 2003
    Date of Patent: October 4, 2005
    Assignees: Hitachi, Ltd., Hitachi High-Technologies Corporation
    Inventors: Zhaohui Cheng, Mari Nozoe
  • Publication number: 20050099189
    Abstract: A pattern inspecting technique, depending on the kind of materials, can reduce damage including shrinkage to materials when the materials are prone to such damage as shrinkage and spoilage caused by electron beam irradiation. This is accomplished by scanning a sample with a primary electron beam, detecting secondary electrons generated, or electrons reflected from the semiconductor device, or both the former and latter electrons, and converting the electrons into signals, and transforming the signals into an image, displaying the image, and detecting defective spots in the circuit pattern of the sample. The irradiation density (dose per unit area) of the electron beam is monitored and limited depending on the kind of material of the circuit pattern under inspection and the inspecting conditions, and damage, such as shrinkage and spoilage to the materials during electron beam irradiation, is reduced to an allowable range.
    Type: Application
    Filed: July 17, 2003
    Publication date: May 12, 2005
    Inventors: Zhaohui Cheng, Mari Nozoe