Patents by Inventor Iqbal K. Bansal

Iqbal K. Bansal 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: 6821908
    Abstract: At least one silicon wafer is loaded into a closed vessel that contains a first solution that includes ammonium hydroxide, hydrogen peroxide and DI water. This acidic solution is removed from the vessel and DI water is introduced into the vessel until wafers are completely immersed. The DI water is then removed from the vessel and a second solution that includes hydrofluoric acid, hydrochloric acid solution and DI water is added to the vessel to fully immerse the wafer. The second solution is then removed from the vessel, and as the second solution is being drained from the vessel, an alcohol solution in a hot and low-pressure nitrogen carrier gas is introduced to the vessel, such that as the level of the liquid within the vessel falls below the height of the wafer within the vessel, the surface of the wafer is dried due to surface tension. The thin coating of alcohol solvent on the wafer ensures that the surface of the wafer is hydrogen terminated, thus hydrophobic.
    Type: Grant
    Filed: September 10, 2001
    Date of Patent: November 23, 2004
    Assignee: Mia-Com Inc.,
    Inventors: Iqbal K. Bansal, Joel L. Goodrich
  • Patent number: 5948699
    Abstract: A wafer backing insert for use in a free mount semiconductor polishing apparatus and process is disclosed wherein the wafer backing insert behind the semiconductor substrate has a diameter less than the diameter of the semiconductor substrate being polished to allow the removal of material at the edge of the substrate to be less than the overall average removal of material across the entire substrate. In a preferred embodiment, the process of the present invention utilizing a wafer backing insert having a diameter less than the diameter of the semiconductor substrate being polished is used in combination with a first polishing step utilizing a conventional wafer backing insert to control the resulting thickness and overall TTV of the polished substrate.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: September 7, 1999
    Assignee: SiBond, L.L.C.
    Inventors: Edwin Lawrence, Iqbal K. Bansal