Patents by Inventor Amitava Gangulee

Amitava Gangulee 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: 4319264
    Abstract: A laminated conductor includes a lower thin film of nickel deposited upon a substrate containing silicon. Upon the film of nickel, a thicker film of gold is deposited as the conductive portion of the conductor. On the upper surface of the gold layer is deposited a thin film of nickel. Failure of the conductor because of electromigration is reduced dramatically as compared with use of molybdenum instead of nickel in the laminated structure.
    Type: Grant
    Filed: December 17, 1979
    Date of Patent: March 9, 1982
    Assignee: International Business Machines Corporation
    Inventors: Amitava Gangulee, Paul S. Ho, James K. Howard, Robert J. Miller
  • Patent number: 4236946
    Abstract: A sputtered thin film of an amorphous material composed of a magnetic transition metal X and element Y plus possibly an element Z has low coercivity for domains in the plane, has a well defined and stable magnetic easy axis which is extremely stable without heating above the Curie point, with a high and flat value of permeability from low frequencies to greater than 10 megahertz. Metal X can include at least one of Fe, Ni, and Co. Element Y can include at least one of Si and B. Element Z can be included composed of Cr, for example.
    Type: Grant
    Filed: March 13, 1978
    Date of Patent: December 2, 1980
    Assignee: International Business Machines Corporation
    Inventors: Joseph A. Aboaf, Jerome J. Cuomo, Amitava Gangulee, Robert J. Kobliska
  • Patent number: 4231816
    Abstract: These amorphous metal-alloy films include nitrogen, greater than about one atomic percent at least one transition metal selected from Cr, Fe, Co and Ni with at least one element forming an amorphous alloy therewith, selected from the "glass forming" elements, i.e., B, Si, Al, C and P. The alloys can be formed by deposition in a vacuum chamber. When films are sputtered, the target is composed of the above alloy elements with at least one element selected from each of the transition metal and glass forming element groups. Sputtering occurs in an atmosphere above about 2% vol. N.sub.2 gas mixed with an inert gas, e.g., Ar. Alloys produced include N, i.e., (Co-Fe-B)N and (Fe-B)N. Above about 2 atomic % N in the film, films have lower values of saturation magnetization 4.pi.M.sub.s. Above a 2% vol. N.sub.2 gas in the plasma, electrical resistivity increases. Over 0.5% vol. N.sub.2 gas in the plasma, the film's effective perpendicular anisotropy field H.sub.k.sup.* increases.
    Type: Grant
    Filed: December 30, 1977
    Date of Patent: November 4, 1980
    Assignee: International Business Machines Corporation
    Inventors: Jerome J. Cuomo, Amitava Gangulee, John Kobliska
  • Patent number: 4166279
    Abstract: A method and resulting structure for forming narrow intermetallic stripes which will carry high currents on bodies such as semiconductors, integrated circuits, and magnetic bubble structures, is set forth. The conductive stripe includes gold with at least one transition metal from the group niobium, zirconium and hafnium. The gold and at least one transition metal are deposited onto a supporting body. The deposited metallic material is then annealed at a temperature between about 200.degree. C. and 500.degree. C. for a time sufficient to form a gold-transition metal compound within a gold matrix. The conductive stripes are formed by masking and removing portions of the annealed metallic material to produce conductive stripes which may have a width of 6.times.10.sup.-4 inches or less. These stripes have significantly improved electromigration performance and do not have significantly increased resistance.
    Type: Grant
    Filed: December 30, 1977
    Date of Patent: August 28, 1979
    Assignee: International Business Machines Corporation
    Inventors: Amitava Gangulee, Paul S. Ho, James K. Howard
  • Patent number: 4012756
    Abstract: In accordance with the disclosure, certain impurities, e.g., alloying additions, are introduced in thin metal film to negate the driving force or the effect of the driving force which causes the hillock formation. Such thin metallic films are usually fabricated on the substrates which have different thermal coefficients of expansion than the film itself, and during thermal cycling stresses can be introduced into the film. This stress may serve as a driving force for atom movement and, therefore, to the formation of hillocks. The vehicle by which the induced stress in a film effects the requisite atom movement is via defect movement, and when the force is compressive this gives rise to hillocks. In the practice of this disclosure, impurity additions introduced into a film affect hillock growth by their interaction with the defects which give rise to the requisite atom movement.
    Type: Grant
    Filed: January 27, 1975
    Date of Patent: March 15, 1977
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Francois M. D'Heurle, Amitava Gangulee