Patents Represented by Attorney Robert Groover, III
  • Patent number: 4758305
    Abstract: A method for patterning small-geometry contacts with sloped sidewalls in integrated circuit fabrication. A multilayer resist process is used, and the spacer layer is undercut by overexposure and overdevelopment at the pattern transfer stage. This provides a cantilever etch mask structure, without the need to use any hardmask layers.
    Type: Grant
    Filed: March 11, 1986
    Date of Patent: July 19, 1988
    Assignee: Texas Instruments Incorporated
    Inventors: Thomas D. Bonifield, Vic B. Marriott, Rhett B. Jucha, Monte A. Douglas
  • Patent number: 4723225
    Abstract: An electrically programmable semiconductor memory device of a type having an array of programmable semiconductor floating gate transistors sets of which are coupled between associated respective source and drain lines, an array programming control transistor and a ground select transistor coupled to each of the drain and source lines. Each selected floating gate transistor in a programming mode is in series with control and ground select transistors between a high voltage Vpp and ground potential. A resistive element in series with a first conducting circuit element establishes a reference current which generates a voltage V.sub.1 at the junction of the resistive element and the circuit element. In a second current leg a second conducting circuit element, a module floating gate transistor biased into a conducting state and a module control transistor are all connected between Vpp and ground such that a voltage V.sub.
    Type: Grant
    Filed: October 15, 1985
    Date of Patent: February 2, 1988
    Assignee: Texas Instruments Incorporated
    Inventors: Jeffrey K. Kaszubinski, Debra J. Dolby, Timmie M. Coffman, John F. Schreck
  • Patent number: 4722075
    Abstract: An array of transistor memory cells of a type in which each cell has a transistor, a ground select switch and a sense amplifier coupling switch. A bias voltage line on which there is established a voltage V.sub.BIAS is coupled to each bit line by a bit line transistor whose gate during a read mode is at least about a voltage V.sub.T above V.sub.BIAS. Similarly, the source of each transistor is coupled to the bias voltage line by a source line transistor whose gate is more than about a voltage V.sub.T about V.sub.BIAS. The foregoing arrangement ensures that for every non-selected transistor that transistor's source voltage will be equal to its drain voltage so that all non-selected transistors will be substantially non-conducting.
    Type: Grant
    Filed: October 15, 1985
    Date of Patent: January 26, 1988
    Assignee: Texas Instruments Incorporated
    Inventors: Jeffrey K. Kaszubinski, David D. Wilmoth, Timmie M. Coffman, John F. Schreck
  • Patent number: 4706011
    Abstract: A circuit for sensing a voltage present on an input line higher than a supply voltage V.sub.DD which includes an isolation switch coupled between the input line and an output line, a threshold adjustment diode coupled in series with the isolation switch also between the input and output lines for establishing a voltage above V.sub.DD at which the isolation switch turns on and a constant current source coupled from an output of the sensing circuit and ground.
    Type: Grant
    Filed: July 7, 1986
    Date of Patent: November 10, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Sossio Vergara, Sebastiano D'Arrigo, Giuliano Imondi
  • Patent number: 4698900
    Abstract: A cross point EPROM array has trenches to provide improved isolation between adjacent buried N+ bitlines at locations where the adjacent buried N+ bitlines are not separated by a FAMOS transistor. This results in improved leakage current, improved punchthrough voltage characteristics, and in improved programmability for the cell.
    Type: Grant
    Filed: March 27, 1986
    Date of Patent: October 13, 1987
    Assignee: Texas Instruments Incorporated
    Inventor: Agerico L. Esquivel
  • Patent number: 4687542
    Abstract: A system for performing one semiconductor manufacturing operation or sequence of operations with reduced particulate contamination. A vacuum-tight wafer carrier, which contains numerous wafers in vacuum in a sealed box, is placed into a platform inside a vacuum load lock. The platform contains slots and protruding fingers to provide accurate registration of the position of the wafer carrier. After the load lock is pumped down, the door of the wafer carrier is opened, and a transfer arm removes wafers from the wafer carrier, in any desired order, and transfers them one by one through a port into a processing chamber.
    Type: Grant
    Filed: October 24, 1985
    Date of Patent: August 18, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Cecil J. Davis, Robert Matthews, Randall C. Hildenbrand
  • Patent number: 4676866
    Abstract: A local interconnect system for VLSI integrated circuits. During self-aligned silicidation of exposed moat and gate regions in a nitrogen atmosphere, a conductive titanium nitride layer is formed overall. A second titanium layer is then deposited overall and again reacted, to thicken the nitride layer without increasing the thickness of the silicide layers. This conductive layer is patterned and etched to provide local interconnects with a sheet resistance of the order to ten ohms per square, and also etch stops. Moreover, this local interconnect level permits contacts to be misaligned with the moat boundary, since the titanium nitride local interconnect layer can be overlapped from the moat up on to the field oxide to provide a bottom contact and diffusion barrier for a contact hole which is subsequently etched through the interlevel oxide. This local interconnect capability fulfills all of the functions which a buried contact capability fulfill, and fulfills other functions as well.
    Type: Grant
    Filed: March 7, 1986
    Date of Patent: June 30, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Thomas E. Tang, Che-Chia Wei, Roger A. Haken, Thomas C. Holloway
  • Patent number: 4675073
    Abstract: A plasma etch process for etching titanium nitride selectively with respect to titanium silicides. A reducing electrode, a low flow rate, and a non-copious fluorine source (such as CF.sub.4) are used to achieve a fluorine-deficient plasma. Preferably the substrate temperature is allowed to rise above 50 C during etching.
    Type: Grant
    Filed: March 7, 1986
    Date of Patent: June 23, 1987
    Assignee: Texas Instruments Incorporated
    Inventor: Monte A. Douglas
  • Patent number: 4673592
    Abstract: The present invention discloses a method for planarizing contact holes, vias, and other surface depressions, during the fabrication of an integrated circuit structure. Differential thermal conductivities are exploited to selectively remove a deposited film of metal from high-thermal-resistance areas, such as silicon dioxide or other insulators, and not from low-thermal-resistance areas, such as silicon or metal. By repetition of this step, very deep depressions, having a high aspect ratio, are reliably filled.
    Type: Grant
    Filed: June 2, 1982
    Date of Patent: June 16, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Vernon R. Porter, Samuel C. Baber
  • Patent number: 4659426
    Abstract: Refractory metals, refractory metal silicide, and polysilicon/refractory metal silicide sandwich structures integrated circuits are etched using carbonyl chemistry. That is, the deposited material is plasma etched using an etchant gas mixture which contains a gas, such as CO2, which can dissociate to provide carbonyl groups (CO) or, in combination with halogen sources, carbonyl halide radicals.
    Type: Grant
    Filed: May 3, 1985
    Date of Patent: April 21, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Clyde R. Fuller, Gordon P. Pollack, Robert H. Eklund, Dave Monahan
  • Patent number: 4657628
    Abstract: A local interconnect system for VLSI integrated circuits. After titanium is deposited for self-aligned silicidation of exposed moat and gate regions in a nitrogen atmosphere, a hardmask is deposited and patterned over the titanium. When a conductive titanium nitride layer is formed overall, it will already be patterned according to this hardmask.
    Type: Grant
    Filed: March 7, 1986
    Date of Patent: April 14, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Thomas C. Holloway, Thomas E. Tang, Che-Chia Wei, Roger A. Haken, David A. Bell
  • Patent number: 4654112
    Abstract: A new process for plasma etching silicon oxides in integrated circuit structures. A chemistry comprising both oxygen and nitrogen trifluoride is used, with oxygen the dominant component. This provides excellent selectivity to silicon. This etch chemistry also erodes photoresist rapidly, so that it is typically used in combination with a hard-masking process. One particular application of this invention is in a cantilever-etch-mask contact profiling process.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: March 31, 1987
    Assignee: Texas Instruments Incorporated
    Inventors: Monte A. Douglas, Thomas D. Bonifield
  • Patent number: 4635344
    Abstract: A low temperature, low encroachment isolation technique using differential oxidation results in an isolated semiconductor body having an N+ substrate (12) and an N epi layer (14) forming a mesa. N+ implants (22a) and (22b) are implanted on opposite sides of the mesa. Oxide is grown over the surface of the device with differential oxidation thus resulting in thick regions (24) over the N+ dopant regions and a thin region (26) over the undopant mesa region.
    Type: Grant
    Filed: August 20, 1984
    Date of Patent: January 13, 1987
    Assignee: Texas Instruments Incorporated
    Inventor: Robert H. Havemann
  • Patent number: 4623417
    Abstract: A magnetron plasma reactor wherein the susceptor is an aluminum arm extending into approximately the middle of a solenoidal magnetic field generated by a dc current.
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: November 18, 1986
    Assignee: Texas Instruments Incorporated
    Inventors: John E. Spencer, Duane Carter, Dave Autery
  • Patent number: 4621411
    Abstract: Optical illumination rather than furnace heating is used to drive in MOSFET source and drain diffusions, preferably using a surface layer of antimony as the dopant source. This results in substantially less overlap between the gate and the source and drain diffusions. Similarly, if the present invention is practiced in a process having gate sidewalls less than zero overlap can be achieved.
    Type: Grant
    Filed: September 28, 1984
    Date of Patent: November 11, 1986
    Assignee: Texas Instruments Incorporated
    Inventors: Robert H. Havemann, Vernon R. Porter
  • Patent number: 4620297
    Abstract: A Schmitt trigger memory cell includes a storage node (20) for storage of data thereon with a current limiter resistor (22) for sinking current therefrom to a source node. A driving transistor (24) supplies current to the storage node (20) from a supply node. The gate of the transistor (24) is supplied by a current limiter resistor (28) from the supply node to turn the transistor (24) on and source current to the storage node (20). A transistor (30) is connected between the gate of the transistor (24) and the storage node (20) for shunting current from the gate of the transistor (24) to the source thereof. The transistor (30) is turned on by pulling the storage node (20) to a low voltage. To turn the transistor (24) on, the voltage on the storage node (20) is pulled high. A transistor (34) supplies current from the supply node to the gate of a transistor (24) during turn on thereof when the storage node (20) is pulled high.
    Type: Grant
    Filed: August 31, 1984
    Date of Patent: October 28, 1986
    Assignee: Texas Instruments Incorporated
    Inventor: Theodore W. Houston
  • Patent number: 4619036
    Abstract: After the extrinsic base region of a bipolar transistor has been formed, and the emitter contact has been patterned and cut, the emitter dopant is deposited or spun on, and the emitter dopant is then driven in using a short pulse of radiant energy. The necessity for high-temperature annealing of the emitter doping is thereby avoided, and the base doping profile is not disturbed by high-temperature annealing steps.
    Type: Grant
    Filed: September 28, 1984
    Date of Patent: October 28, 1986
    Assignee: Texas Instruments Incorporated
    Inventors: Robert H. Havemann, Samuel C. Baber
  • Patent number: 4613885
    Abstract: A high-voltage CMOS process, providing (for 5 micron geometries) both field thresholds and junction breakdowns in excess of 20 volts, wherein only one channel stop implant is used. A double-well process in an epitaxial structure is used. Phosphorus is preferably used as the dopant for the N-tank, and boron is used for the blanket channel stop implant. The boron tends to leach into oxide, and the phosphorus tends to accumulate at the surface, and a high field threshold is achieved over both PMOS and NMOS regions.
    Type: Grant
    Filed: January 12, 1984
    Date of Patent: September 23, 1986
    Assignee: Texas Instruments Incorporated
    Inventor: Roger A. Haken
  • Patent number: 4613956
    Abstract: The dielectric between the floating gate and the control gate, in an EEPROM or other floating gate memory is made by forming an oxide/nitride stack over the (first polysilicon) control gate. This dielectric not only provides a very high specific capacitance, which is desired to provide tight coupling of the control to the floating gate, but also provides excellent dielectric integrity. Moreover, the thickness of this dielectric layer does not exhibit any uncontrolled increase during exposure to second gate oxidation. Thus, the polysilicon-to-polysilicon dielectric is not only of high specific capacitance and high integrity, it is also very uniform.
    Type: Grant
    Filed: February 23, 1983
    Date of Patent: September 23, 1986
    Assignee: Texas Instruments Incorporated
    Inventors: James L. Paterson, Roger A. Haken
  • Patent number: 4611131
    Abstract: A memory decoder wherein a power-up device is interposed between a NOR decoder and ground (VSS), rather than between the decoder and VDD. Preferably the signal to the power-up transistor is itself decoded, so that the power-consuming NOR circuits are inactive over a majority of the chip, even during power-up conditions.
    Type: Grant
    Filed: August 31, 1983
    Date of Patent: September 9, 1986
    Assignee: Texas Instruments Incorporated
    Inventor: Ashwin H. Shah