Patents by Inventor Praveen A. Chaudhari

Praveen A. Chaudhari 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: 4515650
    Abstract: The present invention provides a method for fabricating large grain semiconductor ribbons suitable for use in solar cells. A molten semiconductor material is discharged onto a rotating cylindrical surface which is rotating with linear velocity of not greater than 36 m/sec.
    Type: Grant
    Filed: December 31, 1981
    Date of Patent: May 7, 1985
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Rene Muller
  • Patent number: 4341942
    Abstract: A wire is positioned in intimate contact with a microcircuit chip above a conductor line or pad on the chip. The line is protected by a layer of passivating or insulating material deposited upon the chip. A short pulse, focussed, energy source such as a laser beam drills a hole through or on the edge of the wire, and also opens a hole drawn through the insulating material to expose the conductor line. Then energy is directed upon the portion of the wire surrounding the hole to melt metal from the wire down into the hole which coalesces with molten metal below to form an electrical and mechanical bond of the wire to the line.
    Type: Grant
    Filed: June 6, 1980
    Date of Patent: July 27, 1982
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, John B. Kiessling, David J. Perlman, Eugene E. Tynan, Robert J. von Gutfeld
  • Patent number: 4293374
    Abstract: A high aspect ratio collimating mask for use in ion beam epitaxy or ion implantation doping is formed through the use of damage-trail-forming materials which are irradiated through a mask and then etched. The high aspect ratio is obtained in part by the sequential formation of a plurality of spaced mask plates. The mask is useful in producing large scale integrated circuits by ion implantation during epitaxial growth of a crystal wafer.
    Type: Grant
    Filed: March 10, 1980
    Date of Patent: October 6, 1981
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Ned J. Chou, Ralph Feder, Alan B. Fowler, James A. VanVechten
  • Patent number: 4264813
    Abstract: The present invention describes an ion source which is capable of producing relatively high density ion currents. The ion source employs an electrically biased ionic conductor to supply ions from a reservoir of the atomic species.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: April 28, 1981
    Assignee: International Business Machines Corportion
    Inventors: G. V. Chandrashekhar, Praveen Chaudhari, Jerome J. Cuomo, Richard J. Gambino, James M. E. Harper
  • Patent number: 4052709
    Abstract: A string of bubble domains having a length equal to that of a column portion to be extracted from a bubble domain lattice array is laterally punched into the input side of the array at the height of the desired column portion. As it enters the array it displaces the adjacent and corresponding portion of the first column, which thus becomes a dislocation dipole. The latter is then propagated through the array by subsequent punching cycles until the corresponding portion of the last column is forced out of the array. At this point the dislocation dipole has passed completely through the array, and the corresponding portions of each column have been displaced one column to the right. The process is then repeated until the desired column portion has been displaced across the array into the last column, and then forced out of the array for reading. By punching the forced out column portions back into the array at the input side the original storage order of the array can be reestablished.
    Type: Grant
    Filed: August 27, 1975
    Date of Patent: October 4, 1977
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Geoffrey Richard Woolhouse
  • Patent number: 4046618
    Abstract: A method of making a large single crystal thin film not dependent upon the size or temperature resistance of the substrate crystal by first depositing an amorphous film of the crystalline material to be produced followed by heating of the amorphous film in such a manner that nucleation of epitaxial grains is propagated through the amorphous film whereby a single crystal thin film is produced.
    Type: Grant
    Filed: February 26, 1975
    Date of Patent: September 6, 1977
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Jerome John Cuomo, John Wauchope Matthews
  • 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
  • Patent number: 3965463
    Abstract: Apparatus using amorphous magnetic compositions having uniaxial anisotropy include bubble domain apparatus, light modulating apparatus, permanent magnet systems, and tape and disc information handling systems. The amorphous magnetic composition can be prepared in thin film or bulk form or as particles in a binder. The anisotropy can be parallel to the plane of a film of this material or perpendicular to the film plane. The amorphous material is comprised of a single element or is a multicomponent system where as at least one of the components has an unimpaired spin so that the composition has a net magnetic moment. The amorphous composition exists as a microcrystalline structure having localized atomic ordering over a distance 25-100 A, or as a substantially amorphous structure where localized atomic ordering is over distances less than 25A. Binary and ternary compositions, either alloys or compounds, are suitable.
    Type: Grant
    Filed: May 27, 1975
    Date of Patent: June 22, 1976
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Jerome J. Cuomo, Richard J. Gambino
  • Patent number: 3949387
    Abstract: A beam addressable file using as a storage medium an amorphous magnetic composition having uniaxial anisotropy. The storage medium can be prepared in thin film or bulk form or as particles in a binder. The storage medium can be comprised of a single element or a multicomponent system where at least one of the components has an unpaired spin so that the composition has a net magnetic moment. The storage comosition exists in a microcrystalline structure (i.e., it has localized atomic ordering over a distance 25-100 angstroms) and also in a substantially amorphous structure (i.e., when the composition has localized atomic ordering only over distances less than 25 angstroms). Binary and ternary compositions, either alloys or compounds, are suitable. particularly good examples are combinations of rare earth elements and transition metal elements.
    Type: Grant
    Filed: August 29, 1972
    Date of Patent: April 6, 1976
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Jerome J. Cuomo, Richard J. Gambino, Thomas R. McGuire