Patents by Inventor Chi-Fu Ni

Chi-Fu Ni 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: 5838716
    Abstract: A method of testing a dry oxidation furnace for leaks which permit the entry of moisture into the oxidizing ambient is described. Such moisture, when present in sufficient concentration, can cause a high degree of boron depletion in silicon at p-type contact interfaces in the manufacture of p-channel MOSFETs. The depleted silicon presents a high resistance component to the contact thereby compromising its performance. A test wafer is subjected to a non-oxidizing ambient in the furnace according to a prescribed procedure. Measurements of the thickness of an oxide layer on the test wafer before and after the procedure indicate the presence of a leak of sufficient proportions to cause a deterioation of contact performance if the oxide grown during the test procedure exceeds between about 25 to 35 Angstroms. The procedure is also useful as a simple means of monitoring an oxidation furnace to provide a record of performance and signal the development of trends which suggest appropriate remedial maintenance.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: November 17, 1998
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Hui-Hua Chang, Yu-Jen Yu, Chi-Fu Ni