Patents by Inventor Ning C. Lee

Ning C. Lee 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).

  • Anti-tombstoning solder alloys for surface mount applications
    Patent number: 6783057
    Abstract: The object of this invention is to employ a solder alloy comprising tin/lead/silver in order to provide a wider solidification range and achieve balance between the surface tensions of both side of a small leadless component. The expanded solidification range slows the melting and wetting time so as to balance the surface tension of the molten solder, and in turn reduces the tombstoning frequency. The preferred Ag concentration is 0.2-0.5% in weight, the more preferred Ag concentration is 0.3-0.4% in weight. For reflow soldering of small leadless components, the pastes made with the alloy compositions of Sn62.6Pb37Ag0.4 and Sn63Pb36.6Ag0.4 results in improvements in tombstoning.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: August 31, 2004
    Assignee: Indium Corporation of America
    Inventors: Benlih Huang, Ning C. Lee
  • Anti-tombstoning solder alloys for surface mount applications
    Publication number: 20020063147
    Abstract: The object of this invention is to employ a solder alloy comprising tin/lead/silver in order to provide a wider solidification range and achieve balance between the surface tensions of both side of a small leadless component. The expanded solidification range slows the melting and wetting time so as to balance the surface tension of the molten solder, and in turn reduces the tombstoning frequency. The preferred Ag concentration is 0.2-0.5% in weight, the more preferred Ag concentration is 0.3-0.4% in weight. For reflow soldering of small leadless components, the pastes made with the alloy compositions of Sn62.6Pb37Ag0.4 and Sn63Pb36.6Ag0.4 results in improvements in tombstoning.
    Type: Application
    Filed: September 20, 2001
    Publication date: May 30, 2002
    Applicant: INDIUM CORPORATION OF AMERICA
    Inventors: Benlih Huang, Ning C. Lee