Patents by Inventor Cheuk Ping Lau

Cheuk Ping Lau 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).

  • Method for backdrilling via stubs of multilayer printed circuit boards with reduced backdrill diameters
    Patent number: 9433084
    Abstract: Methods of backdrilling printed circuit boards (PCBs) to remove via stubs and related apparatuses. The method may include removing a via stub through a combination of backdrilling and chemical etching. The backdrilling may remove a masking layer from the via stub. Portions of an underlying layer may remain in the region of the via stub after the backdrilling is completed. The remaining portions of the underlying layer may be removed in a subsequent etching process thereby removing the via stub from the PCB. As the backdrilling step may be used for the limited purpose of removing the outer layer and portions of the underlying layer remaining in the via can be tolerated, the diameter of the backdrilling need not be as large as traditional backdrilling where all layers within the via must be ensured of being completely removed.
    Type: Grant
    Filed: October 10, 2012
    Date of Patent: August 30, 2016
    Assignee: Flextronics AP, LLC
    Inventor: Cheuk Ping Lau
  • Method for backdrilling via stubs of multilayer printed circuit boards with reduced backdrill diameters
    Patent number: 8302301
    Abstract: Methods of backdrilling printed circuit boards (PCBs) to remove via stubs and related apparatuses. The method may include removing a via stub through a combination of backdrilling and chemical etching. The backdrilling may remove a masking layer from the via stub. Portions of an underlying layer may remain in the region of the via stub after the backdrilling is completed. The remaining portions of the underlying layer may be removed in a subsequent etching process thereby removing the via stub from the PCB. As the backdrilling step may be used for the limited purpose of removing the outer layer and portions of the underlying layer remaining in the via can be tolerated, the diameter of the backdrilling need not be as large as traditional backdrilling where all layers within the via must be ensured of being completely removed.
    Type: Grant
    Filed: March 8, 2011
    Date of Patent: November 6, 2012
    Assignee: Flextronics AP, LLC
    Inventor: Cheuk Ping Lau
  • BACKDRILLING OF MULTILAYER PRINTED CIRCUIT BOARDS
    Publication number: 20110240348
    Abstract: Methods of backdrilling printed circuit boards (PCBs) to remove via stubs and related apparatuses. The method may include removing a via stub through a combination of backdrilling and chemical etching. The backdrilling may remove a masking layer from the via stub. Portions of an underlying layer may remain in the region of the via stub after the backdrilling is completed. The remaining portions of the underlying layer may be removed in a subsequent etching process thereby removing the via stub from the PCB. As the backdrilling step may be used for the limited purpose of removing the outer layer and portions of the underlying layer remaining in the via can be tolerated, the diameter of the backdrilling need not be as large as traditional backdrilling where all layers within the via must be ensured of being completely removed.
    Type: Application
    Filed: March 8, 2011
    Publication date: October 6, 2011
    Applicant: FLEXTRONICS AP, LLC
    Inventor: Cheuk Ping Lau