Patents by Inventor Chester Xiaowen Chien

Chester Xiaowen Chien 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: 8222599
    Abstract: A method of measuring a three-dimensional device in a wafer is provided. The method comprises the step of forming a trench in the wafer. The trench has a facet passing through the three-dimensional device a predetermined offset from a desired image position. The method further comprises iteratively, until a remaining distance between the facet and the desired image position is less than a predetermined threshold, adjusting one or more parameters of a polishing beam based on the remaining distance, polishing the facet with the polishing beam to position the facet closer to the desired image position, and measuring the remaining distance.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: July 17, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventor: Chester Xiaowen Chien
  • Patent number: 8097846
    Abstract: A method for measuring three-dimensional devices in a wafer comprises the step of obtaining a plurality of cross-sectional images of a corresponding plurality of three-dimensional devices in the wafer. The plurality of three-dimensional devices have essentially identical geometries. Each cross-sectional image is obtained from a plane in the corresponding three-dimensional device at a predetermined distance from a fiducial mark thereof. The predetermined distance is different for each of the plurality of cross-sectional images. The method further comprises the step of determining the geometries of the plurality of three-dimensional devices based on the cross-sectional images thereof.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: January 17, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Alexandre Anguelouch, Lei Wang, Chester Xiaowen Chien
  • Patent number: 6721138
    Abstract: An inductive transducer having first and second magnetic pedestals disposed between first and second magnetic pole layers and adjacent to a media-facing surface, the pedestals separated by a submicron, nonmagnetic gap. The first pedestal extends less than the second pedestal from the media-facing surface, defining a short throat height. The second pedestal extends further to provide sufficient area for stitching to the second pole layer. The stitching and the thickness provided by the pedestals allow plural coil layers to be disposed between the pole layers, and the second pedestal, as well as other features, can be defined by high-resolution photolithography. The two coil layers have lower resistance, lower inductance and allow the pole layers to be shorter, improving performance. All or part of either or both of the pedestals may be formed of high magnetic saturation material, further enhancing performance.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: April 13, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Xizeng Shi, Hugh Craig Hiner, Zi-Wen Dong, Francis Liu, Matthew R. Gibbons, Joyce Anne Thompson, William D. Jensen, Chester Xiaowen Chien, Yugang Wang
  • Patent number: 6661625
    Abstract: A thin film read/write head with a high performance read section that includes a spin-dependent tunneling sensor composed of a new low resistance metal oxide tunneling barrier material, such as chromium oxide (CrxOy) or niobium oxide (NbOz). The chromium oxide material (CrxOy) can be, for example: Cr3O4, Cr2O3, CrO2, CrO3, Cr5O12, Cr6O15, other stoichiometry, or any combination thereof. The niobium oxide (NbOz) can be, for example: NbO, NbO2, Nb2O5, Nb2O3, Nb12O29, Nb11O27, other stoichiometry, or any combination thereof. The chromium oxide and the niobium oxide material provides a very low sensor resistance with an acceptable magnetoresistance ratio, which will enable the fabrication of high density read sensors, and thus read heads with high data transfer rate.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: December 9, 2003
    Inventors: Kyusik Sin, Ming Mao, Hua-Ching Tong, Chester Xiaowen Chien
  • Patent number: 6448765
    Abstract: A magnetic force microscope (MFM) needle has a magnetic material with a magnetic moment that is pinned in a preferred direction. The magnetic moment can be of lower than conventional magnitude without risking an undesirable change in the direction of magnetization. The magnetic needle can have a ferromagnetic layer (or layers) that is stabilized by an antiferromagnetic layer (or layers). The needle can be employed as a magnetoresistance sensitivity microscope (MSM) to map the sensitivity of a magnetic sensor, such as a magnetoresistive (MR) or giant magnetoresistive (GMR) sensor. Alternatively, the needle can be employed in measuring magnetic fields, such as with a high frequency magnetic force microscope (HFMFM).
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: September 10, 2002
    Assignee: Read-Rite Corporation
    Inventors: Hong Chen, Chester Xiaowen Chien