Patents by Inventor Hormazdyar M. Dalal

Hormazdyar M. Dalal 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: 5976975
    Abstract: Capping a low resistivity metal conductor line or via with a refractory metal allows for effectively using chemical-mechanical polishing techniques because the-hard, reduced wear, properties of the refractory metal do not scratch, corrode, or smear during chemical-mechanical polishing. Superior conductive lines and vias are created using a combination of both physical vapor deposition (e.g., evaporation or collimated sputtering) of a low resistivity metal or alloy followed by chemical vapor deposition (CVD) of a refractory metal and subsequent planarization. Altering a ratio of SiH.sub.4 to WF.sub.6 during application of the refractory metal cap by CVD allows for controlled incorporation of silicon into the tungsten capping layer. Collimated sputtering allows for creating a refractory metal liner in an opening in a dielectric which is suitable as a diffusion barrier to copper based metalizations as well as CVD tungsten.
    Type: Grant
    Filed: July 10, 1998
    Date of Patent: November 2, 1999
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 5889328
    Abstract: Capping a low resistivity metal conductor line or via with a refractory metal allows for effectively using chemical-mechanical polishing techniques because the hard, reduced wear, properties of the refractory metal do not scratch, corrode, or smear during chemical-mechanical polishing. Superior conductive lines and vias are created using a combination of both physical vapor deposition (e.g., evaporation or collimated sputtering) of a low resistivity metal or alloy followed by chemical vapor deposition (CVD) of a refractory metal and subsequent planarization. Altering a ratio of SiH.sub.4 to WF.sub.6 during application of the refractory metal cap by CVD allows for controlled incorporation of silicon into the tungsten capping layer. Collimated sputtering allows for creating a refractory metal liner in an opening in a dielectric which is suitable as a diffusion barrier to copper based metalizations as well as CVD tungsten.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: March 30, 1999
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 5808853
    Abstract: This invention is directed to a capacitor having a multilevel interconnection technology. At least one solder ball is reflowed and secured onto the capacitor. The solder ball is in electrical communication with the capacitor through a contact. On this reflowed solder ball a cap of low melting point metal is secured. This can be done in a number of ways. The preferred way is to positioning a mask over the solder ball such that a portion of the solder ball is exposed through openings in the mask. At least one layer of a low melting point metal is deposited on the exposed surface of the solder ball through the mask, and thereby forming a capacitor with a multilevel interconnect cap. The low melting point metal can interact with the surface of the solder ball to form a cap of an eutectic or a liquefied portion. The cap portion can then be joined to the object.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: September 15, 1998
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Gene Joseph Gaudenzi, Rebecca Y. Gorrell, Mark A. Takacs, Kenneth J. Travis, Jr.
  • Patent number: 5729896
    Abstract: A structure and method is disclosed for directly attaching a device or package on flexible organic circuit carriers having low cost and high reliability. IC chips with a new solder interconnect structure, comprised of a layer of pure tin, deposited on the top of high melting Pb--Sn solder balls are employed for joining. These methods, techniques and metallurgical structures enables direct attachment of electronic devices of any complexity to any substrate and to any level of packaging hierarchy. Also, devices or packages having other joining technologies, eg. SMT, BGA, TBGA, etc. could be joined onto the flexible circuit carrier.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: March 24, 1998
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Kenneth M. Fallon, Gene J. Gaudenzi, Cynthia S. Milkovich
  • Patent number: 5634268
    Abstract: A structure and a method is disclosed for making a laminated circuit carrier card for the purpose of making a Direct Chip Attached Module (DCAM) with low cost and high reliability. The carrier is made using an organic or an inorganic laminated carrier having at least one surface available for direct chip mount. The chip has at least one solder ball with a cap of low melting point metal. The surface of the carrier has electrical features that are directly connected to the low melting point metal on the solder ball of the chip to form the eutectic and this way the chip is directly attached to the carrier.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 3, 1997
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Kenneth M. Fallon, Gene J. Gaudenzi
  • Patent number: 5585673
    Abstract: Capping a low resistivity metal conductor line or via with a refractory metal allows for effectively using chemical-mechanical polishing techniques because the hard, reduced wear, properties of the refractory metal do not scratch, corrode, or smear during chemical-mechanical polishing. Superior conductive lines and vias are created using a combination of both physical vapor deposition (e.g., evaporation or collimated sputtering) of a low resistivity metal or alloy followed by chemical vapor deposition (CVD) of a refractory metal and subsequent planarization. Altering a ratio of SiH.sub.4 to WF.sub.6 during application of the refractory metal cap by CVD allows for controlled incorporation of silicon into the tungsten capping layer. Collimated sputtering allows for creating a refractory metal liner in an opening in a dielectric which is suitable as a diffusion barrier to copper based metalizations as well as CVD tungsten.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: December 17, 1996
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 5470788
    Abstract: A method of providing interconnections to a semiconductor integrated chip designed to eliminate electromigration. The method includes the steps of forming an interconnection with segments of Al interspersed with segments of a refractory metal, wherein each aluminum segments is followed by a segment of refractory metal, aligning the aluminum and refractory metal segments with respect to each other ensuring electrical continuity.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: November 28, 1995
    Assignee: International Business Machines Corporation
    Inventors: Glenn A. Biery, Daniel M. Boyne, Hormazdyar M. Dalal
  • Patent number: 5434451
    Abstract: Tungsten studs and tungsten lined studs that make low resistance thermally stable ohmic or Schottky contacts to active devices on a semiconductor substrate are made by first defining a triplex metallurgical structure. The triplex metallurgical structure includes an ohmic layer, a barrier layer and a sacrificial layer. Then, a blanket layer of insulator is deposited and polished, or etched, or both, until the stud metallurgy is exposed. The sacrificial layer is then etched out, leaving holes self-aligned to the contacts and to the ohmic and the barrier layers. A blanket layer of CVD tungsten is then deposited and the substrate is polished, or etched, or both, to remove excess tungsten. The metal contact studs can be simultaneously formed with patterned interconnection lines which are self-aligned to each other and also to the contact studs.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: July 18, 1995
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Kevin J. Hutchings, Hazara S. Rathore
  • Patent number: 5427983
    Abstract: A thin-layer metallization structure in which the final gold layer is deposited by evaporation with the surface onto which it is evaporated maintained at an elevated temperature. By evaporating the uppermost gold layer of the structure at an elevated substrate temperature, the gold atoms have a higher mobility, causing the deposited gold to spread over the edge of the structure and cover the otherwise exposed edges, including the edge at the copper interface.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: June 27, 1995
    Assignee: International Business Machines Corporation
    Inventors: Umar M. U. Ahmad, Harsaran S. Bhatia, Satya P. S. Bhatia, Hormazdyar M. Dalal, William H. Price, Sampath Purushothaman
  • Patent number: 5426330
    Abstract: A device includes a substrate, at least one dielectric layer positioned on said substrate, and metalization positioned in an opening in the at least one dielectric layer and extending a predetermined distance towards the substrate from a surface which is substantially coplanar with a surface of the at least one dielectric layer. The metalization includes a low resistivity metal or alloy encapsulated by a refractory metal or alloy having a resistivity greater than that of the low resistivity metal or alloy and having a columnar structure. The metalization has a plurality of sides in cross-section, at least three sides of the plurality of sides being substantially formed of a refractory metal or alloy having a common composition, at least two sides of the plurality of sides extending substantially the predetermined distance, and all of the plurality of sides being formed within the opening in the at least one dielectric layer.
    Type: Grant
    Filed: September 21, 1993
    Date of Patent: June 20, 1995
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 5403779
    Abstract: Capping a low resistivity metal conductor line or via with a refractory metal allows for effectively using chemical-mechanical polishing techniques because the hard, reduced wear, properties of the refractory metal do not scratch, corrode, or smear during chemical-mechanical polishing. Superior conductive lines and vias are created using a combination of both physical vapor deposition (e.g., evaporation or collimated sputtering) of a low resistivity metal or alloy followed by chemical vapor deposition (CVD) of a refractory metal and subsequent planarization. Altering a ratio of SiH.sub.4 to WF.sub.6 during application of the refractory metal cap by CVD allows for controlled incorporation of silicon into the tungsten capping layer. Collimated sputtering allows for creating a refractory metal liner in an opening in a dielectric which is suitable as a diffusion barrier to copper based metalizations as well as CVD tungsten.
    Type: Grant
    Filed: August 12, 1992
    Date of Patent: April 4, 1995
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 5401677
    Abstract: An improved process for the formation of high quality, high yield platinum silicides on silicon wafers uses a post sputter platinum deposition and high vacuum bake to complete the first step of silicide reaction, resulting in Pt.sub.2 Si formation before sinter. This additional process step is then followed by a 500.degree. to 900.degree. C. sinter. The use of a high vacuum bake provides easy control of O.sub.2 and H.sub.2 O impurities. The vacuum bake can be done in any high vacuum tool. The bake temperatures range from 200.degree. to 450.degree. C. at 5.times.10.sup.-6 torr, with an in-situ bake time of 3 to 5 minutes or an ex-situ bake time of 10 to 30 minutes, depending on batch size or tool. A particular advantage of the process is that it can be performed in existing tools.
    Type: Grant
    Filed: December 23, 1993
    Date of Patent: March 28, 1995
    Assignee: International Business Machines Corporation
    Inventors: Robert D. Bailey, Cyril Cabral, Jr., Brian Cunningham, Hormazdyar M. Dalal, James M. Harper, Viraj Sardesai, Horatio S. Wildman, Thomas O. Williams
  • Patent number: 5300813
    Abstract: A contact structure for a semiconductor device having a first refractory metal layer formed only at the bottom of a contact hole. The first refractory metal is selected from a group comprising titanium (Ti), titanium alloys or compounds such as Ti/TiN, tungsten (W), titanium/tungsten (Ti/W) alloys, or chromium (Cr) or tantalum (Ta) and their alloys or some other suitable material. A low resistivity layer comprising a single, binary or ternary metalization is deposited over the first refractory metal layer in the contact hole by a method such as PVD using evaporation or collimated sputtering. The low resistivity layer has side walls which taper inwardly toward one another with increasing height of the layer and the low resistivity layer does not contact the side walls of the contact hole. The low resistivity layer may be Al.sub.x Cu.sub.y (x+y=1; x.gtoreq.0, y.gtoreq.0), ternary alloys such as Al-Pd-Cu or multicomponent alloys such as Al-Pd-Nb-Au.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: April 5, 1994
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Jerome J. Cuomo, Hormazdyar M. Dalal, Louis L. Hsu
  • Patent number: 4831494
    Abstract: Disclosed is a multilayer capacitor consisting of a plurality of laminae with each of the laminae including a conductive plate portion and a non-conductive sheet portion. The conductive plate portion has at least one tab projecting to at least one edge of the conductive plate portion with the maximum number of tabs per conductive plate portion being limited to avoid excessive lateral congestion. The laminae are divided into different groups with the laminae from each group having the same number and location of tabs and with the laminae from different groups differing by at least the location of the tabs.
    Type: Grant
    Filed: June 27, 1988
    Date of Patent: May 16, 1989
    Assignee: International Business Machines Corporation
    Inventors: Allen J. Arnold, Michael E. Bariether, Shin-Wu Chiang, Hormazdyar M. Dalal, Robert A. Miller, Frank A. Montegari, James M. Oberschmidt, David T. Shen
  • Patent number: 4379832
    Abstract: A method for making low barrier Schottky devices by the electron beam evaporation of a reactive metal such as tantalum, titanium, hafnium, tungsten, molybdenum, and niobium which is selectively deposited at a semiconductor surface such as n-type silicon using a photoresist mask. The method includes a series of steps during the deposition of the barrier metal for degassing the semiconductor substrate, photoresist mask, reactive metal charge and deposition chamber. More particularly, the method includes steps for preliminarily degassing the substrate, mask and surrounding chamber by infra red heating under vacuum followed by steps for preliminarily degassing the charge and surrounding chamber, while the substrate and mask are shielded by electron beam heating the charge while under vacuum.
    Type: Grant
    Filed: August 31, 1981
    Date of Patent: April 12, 1983
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, John J. Lowney
  • Patent number: 4215156
    Abstract: A silicon semiconductor device having contacts which include tantalum. The tantalum is useful in particular for fabricating Schottky barrier diodes having a low barrier height. The method includes: precleaning the silicon substrate prior to depositing the tantalum; depositing the tantalum at low pressure and low substrate temperature to avoid oxidation of the tantalum; and sintering the contact to reduce any interfacial charges and films remaining between the silicon and tantalum. When a metal which reacts with silicon during processing, such as aluminum, is used as interconnection metallurgy, a layer of chrome must be deposited between the tantalum and aluminum.
    Type: Grant
    Filed: August 26, 1977
    Date of Patent: July 29, 1980
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Majid Ghafghaichi, Lucian A. Kasprzak, Hans Wimpfheimer
  • Patent number: 4214256
    Abstract: A silicon semiconductor device having contacts which include tantalum. The tantalum is useful in particular for fabricating Schottky barrier diodes having a low barrier height. The method includes: precleaning the silicon substrate prior to depositing the tantalum; depositing the tantalum at low pressure and low substrate temperature to avoid oxidation of the tantalum; and sintering the contact to reduce any interfacial charges and films remaining between the silicon and tantalum. When a metal which reacts with silicon during processing, such as aluminum, is used as interconnection metallurgy, a layer of chrome must be deposited between the tantalum and aluminum.
    Type: Grant
    Filed: September 8, 1978
    Date of Patent: July 22, 1980
    Assignee: International Business Machines Corporation
    Inventors: Hormazdyar M. Dalal, Majid Ghafghaichi, Lucian A. Kasprzak, Hans Wimpfheimer