Patents Represented by Attorney William R. McClellan
  • Patent number: 4528451
    Abstract: Apparatus for controlling the gap between localized vacuum processing envelope apparatus and a workpiece as the workpiece, typically a semiconductor wafer, is moved laterally with respect to the envelope apparatus. The envelope apparatus includes an envelope which defines an internal vacuum processing zone and a generally planar tip spaced from the workpiece during processing by the gap. The gap control apparatus includes a gap sensor for measuring the gap, a control circuit for comparing the measured gap with a required gap and generating an error signal, and an actuating means for varying the gap in response to the error signal. The gap can be sensed by sensing the pressure level in the vacuum processing apparatus. The actuating means can include a plurality of piezoelectric actuators which can vary both the gap and the angle of the workpiece with respect to the tip of the vacuum processing apparatus.
    Type: Grant
    Filed: October 19, 1982
    Date of Patent: July 9, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Paul F. Petric, Michael S. Foley, Mark W. Utlaut, Joseph A. Laiacano
  • Patent number: 4527094
    Abstract: A frequency agile magnetron employs an altitude compensation vacuum envelope external to the vacuum envelope of the magnetron. The tuning assembly of the magnetron includes a tuning plunger coupled through a first bellows assembly to one end of a tuning shaft. The tuning shaft is coupled at its opposite end through a second bellows assembly to the compensation vacuum envelope. When the two bellows assemblies are identical, atmospheric forces acting upon the tuning shaft are balanced at any altitude. Translation of the tuning assembly is provided by an actuator such as a linear motor coupled to the tuning shaft. Improved transfer of heat from the resonant cavity is provided.
    Type: Grant
    Filed: October 19, 1982
    Date of Patent: July 2, 1985
    Assignee: Varian Associates, Inc.
    Inventors: William A. Gerard, Robert J. Foreman
  • Patent number: 4524261
    Abstract: Localized vacuum envelope apparatus includes a housing member having a bottom plate with a downwardly extending first sleeve and an upwardly extending flange. The flange includes ports for vacuum pumping and is adapted for attachment to an electron beam column. The apparatus further includes a lower plate having a second downwardly extending sleeve and an upper plate having a third downwardly extending sleeve. The first, second and third sleeves, which can have a truncated conical shape and are concentric, define vacuum zones. Channels are provided for connecting the vacuum zones to individual ports. The tips of the sleeves are coplanar and form the tip of the vacuum envelope. A noncontacting graded vacuum seal is formed between the tip of the vacuum envelope and a workpiece. The housing member and the upper plate can be ferromagnetic material to provide double magnetic shielding.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: June 18, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Paul F. Petric, Michael S. Foley
  • Patent number: 4522845
    Abstract: Multichromatic radiation is applied rapidly to silicon or polysilicon placed in contact with a silicide-forming metal to form metal silicide having low resistivity without deleterious later diffusion of dopants in adjacent single crystal or polysilicon. The radiation is applied to a metal deposited on silicon or to a metal codeposited with or to silicide deposited from a metal-Si composite target. The temperatures preferably rise to between 600.degree. C. and 1200.degree. C. and the total heating periods are less than about one minute, with 10 to 30 seconds being typical.
    Type: Grant
    Filed: June 20, 1983
    Date of Patent: June 11, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Ronald A. Powell, Ronald T. Fulks
  • Patent number: 4520040
    Abstract: A ferromagnetic film for magnetic recording comprises a copper substrate having particles of iron and iron oxides dispersed in the surface layer of the copper. The particles have maximum dimensions in the range between 50 and 500 Angstroms. The ferromagnetic film can be formed by ion implantation of iron ions into the copper substrate followed by heat treatment to permit growth of ferromagnetic particles to the desired size. As an alternative to ion implantation, the iron can be deposited on the copper substrate by sputtering or evaporation and mixed with the copper by ion beam mixing.
    Type: Grant
    Filed: December 15, 1983
    Date of Patent: May 28, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Bernhard F. Cordts
  • Patent number: 4517276
    Abstract: Photoresist compositions are provided whereby metals are incorporated into the resist by providing a photoresist composition comprising the reaction product of an organic resist which has at least one reactive hydroxyl or amino group with an organometallic compound. Also provided is a process for generating a pattern on a substrate by coating the substrate with a thin film of the photoresist composition which comprises the reaction product of the organic resist which has at least one reactive hydroxyl or amino group with an organometallic compound. The photoresist compositions are particularly suitable for use in diazo-type electron beam procedures.
    Type: Grant
    Filed: November 29, 1982
    Date of Patent: May 14, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Carol R. Lewis
  • Patent number: 4516050
    Abstract: A multipole electron-bombardment type ion source includes an ion chamber defined by chamber walls and magnetic elements of an electrically insulating, permanently magnetized material. The magnetic elements provide mechanical support for anode elements and electrically isolate the anode elements from the chamber walls. In a preferred embodiment, the magnetic elements and the anode elements form a layered structure.
    Type: Grant
    Filed: July 14, 1982
    Date of Patent: May 7, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Carl J. Russo
  • Patent number: 4514689
    Abstract: Apparatus for high resolution sensing of the position of a rapidly moving member. The apparatus includes at least two linear variable differential transformers (LVDT's) each having a magnetic core coupled to the movable member. A signal source and a phase shifter provide energizing signals to the primary coil of each LVDT. The energizing signals have the same frequency but are phase shifted relative to each other. The induced secondary voltages of the LVDT's are sampled by synchronous detectors, the outputs of which are combined by an adder into a high resolution output signal. When two LVDT's are utilized, the energizing signals have a relative phase shift of 90.degree. and the effective position sampling rate is doubled. The apparatus can be used to sense the operating frequency of a tunable magnetron.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: April 30, 1985
    Assignee: Varian Associates, Inc.
    Inventor: William A. Gerard
  • Patent number: 4513430
    Abstract: Apparatus for sensing a missing or broken wafer in an automated wafer transfer system. The apparatus includes means for moving a wafer transfer mechanism from a first position along a prescribed path. A counter coupled to an oscillator is enabled when the wafer transfer mechanism and a wafer are moved away from the first position. A photosensor senses the presence of the wafer at a second position along the prescribed path and inhibits the counter. The count stored in the counter is compared with a predetermined count corresponding to the time required for movement of an unbroken wafer to the second position. If the counts do not agree, a missing or broken wafer is indicated and corrective action is taken.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: April 23, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Mahasukh Vora, Rajender Malhotra
  • Patent number: 4512812
    Abstract: A method for reducing contamination in a vacuum processing chamber includes introducing into the vacuum chamber a gas selected to react with the contaminant and form a compound more volatile than the contaminant. The volatile compound is then removed from the vacuum chamber, typically by vacuum pumping. In one embodiment, the vacuum chamber is an ion implantation chamber, the contaminant is phosphorous and the gas is water vapor, which reacts with the phosphorous to form phosphine gas or other high vapor pressure phosphorous-containing substances.
    Type: Grant
    Filed: September 22, 1983
    Date of Patent: April 23, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Reuel B. Liebert, Carl J. Russo
  • Patent number: 4508161
    Abstract: Apparatus and method are provided for effecting gas-assisted, solid-to-solid thermal transfer with a semiconductor wafer. A semiconductor wafer is loaded at its periphery onto a shaped platen. Sufficient contact pressure from the loading is produced between the wafer and the platen so that significant gas pressure may be accommodated against the back side of the wafer without having the wafer bow outwardly or break. Gas under pressure is introduced into the microscopic void region between the platen and the wafer. The gas fills the microscopic voids between the platen and semiconductor wafer. The gas pressure approaches that of the preloading contact pressure without any appreciable increase in the wafer-to-platen spacing. Since the gas pressure is significantly increased without any increase in the wafer-to-platen gap, the thermal resistance is reduced and solid-to-solid thermal transfer with gas assistance produces optimum results.
    Type: Grant
    Filed: March 2, 1984
    Date of Patent: April 2, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Scott C. Holden
  • Patent number: 4506184
    Abstract: A deformable vacuum pin chuck includes a thin silicon chuck for supporting a semiconductor wafer during lithographic processing and a number of piezoelectric transducers for selectively deforming the chuck. Chuck deformation caused by application of electric potentials to selected transducers may be used to correct flatness deviations in the wafer and, thereby, a desired degree of flatness of the semiconductor wafer may be obtained.
    Type: Grant
    Filed: January 10, 1984
    Date of Patent: March 19, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Graham J. Siddall
  • Patent number: 4504194
    Abstract: Method and apparatus for high speed vacuum pumping of an air lock. A vacuum pumped expansion tank having a volume larger than the volume of the air lock is coupled through a valve to the air lock. When evacuation of the air lock is desired, the valve is opened for a brief duration and the gas in the air lock rapidly expands into the expansion tank. Multiple pumping stages, each including a vacuum pumped expansion tank coupled through a valve to the air lock, can be utilized to decrease the final pressure in the air lock. The valves are sequentially opened to permit sequential expansion of the gas in the air lock into the expansion tanks. Multiple air locks can time share the same pumping system.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: March 12, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Scott C. Holden
  • Patent number: 4503087
    Abstract: A process for high temperature, rapid drive-in diffusion employs a planar blackbody source placed in parallel alignment with a semiconductor wafer in a vacuum processing chamber. The wafer is rapidly heated, preferably to a temperature in the range of 1100.degree. C. to 1300.degree. C. and primarily by radiation which promotes uniformity. Typical diffusions are completed in less than one minute. In order to control diffusion distance at elevated temperatures, the process time and source temperature are carefully controlled, and the peak wafer temperature is monitored.
    Type: Grant
    Filed: August 29, 1983
    Date of Patent: March 5, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Carl J. Russo
  • Patent number: 4499752
    Abstract: A counterflow helium mass spectrometer leak detector includes a test port for receiving a gas sample including the tracer gas helium, a high vacuum pump such as a diffusion pump and a mass spectrometer tuned to detect the helium. The mass spectrometer is coupled to the inlet of the high vacuum pump. The leak detector further includes a cold trap containing liquid nitrogen coupled between the test port and the foreline, or outlet port, of the high vacuum pump. The helium received at the test port passes in reverse, or counterflow, direction through the high vacuum pump to the mass spectrometer. One or more mechanical vacuum pumps insure that the pressure at the foreline of the high vacuum pump is maintained at a prescribed level during a leak test. The cold trap condenses contaminants, water vapor and other gases from the gas sample and prevents backstreaming of oil from mechanical vacuum pumps.
    Type: Grant
    Filed: June 22, 1983
    Date of Patent: February 19, 1985
    Assignee: Varian Associates, Inc.
    Inventors: Paul R. Fruzzetti, Philip J. Leavitt, Frank J. Nuzzi
  • Patent number: 4498833
    Abstract: Apparatus for programmably orienting a semiconductor wafer in an ion implantation system so as to limit channeling or to control the depth of penetration of impinging ions. The apparatus is associated with a processing chamber door and includes a rotatable vacuum chuck for engaging the wafer and a motor for rotating the vacuum chuck and the wafer through a preselected angular displacement. The apparatus further includes a programmable control assembly operative to deenergize the motor upon sensing rotation of the vacuum chuck through the preselected angular displacement. The wafer orientation apparatus is typically utilized in a system for the vertical transfer of wafers between a cassette and a processing chamber.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: February 12, 1985
    Assignee: Varian Associates, Inc.
    Inventor: Richard J. Hertel
  • Patent number: 4486652
    Abstract: A processor apparatus is provided in which a blackbody radiator having a constant planar energy flux characteristic is placed in opposition to semiconductor material. The blackbody source produces a constant planar energy flux to uniformly heat the material. The source is heated to a sufficiently high temperature for a sufficient time to anneal or activate a semiconductor wafer or to epitaxially regrow a thin epitaxial film. The processor is operated by accomplishing the steps of presenting a blackbody radiator in opposition to semiconductor material to be thermally treated, radiatively heating the material to a sufficiently high temperature for a sufficient time to accomplish the desired process result, and cooling and removing the material. In the interval between presentation of successive samples of the material to the source, the source may be shuttered or idled to reduce energy consumption.
    Type: Grant
    Filed: May 10, 1983
    Date of Patent: December 4, 1984
    Assignee: Varian Associates, Inc.
    Inventors: Richard S. Muka, Carl J. Russo
  • Patent number: 4481406
    Abstract: A heater assembly for annealing a semiconductor wafer in a vacuum chamber includes a blackbody source having a constant planar energy flux charactertistic and a wafer support for supporting the wafer adjacent to, but not spaced apart from, the source in planar parallel alignment therewith. The heater assembly further includes radiation shields and a housing providing support for the source, the wafer support and the radiation shields in fixed relationship. The housing includes a heat sink for removal of thermal energy and a slot for insertion and removal of the wafer. The heater assembly confines thermal energy and reduces input energy requirements. In addition, the requirement for a movable shutter is eliminated.
    Type: Grant
    Filed: January 21, 1983
    Date of Patent: November 6, 1984
    Assignee: Varian Associates, Inc.
    Inventor: Richard S. Muka
  • Patent number: 4480235
    Abstract: The cathode of a coaxial magnetron has a cylindrical electron emitter with a radially extending projection which is asymmetrical with respect to the axis of the emitter. The projection suppresses starting of the magnetron in the TE.sub.121 mode and reduces starting jitter. In a preferred embodiment, the projection is in the form of a circumferential ridge extending around approximately one-half the circumference of the cylindrical surface and is centrally located thereon. The projection is oriented at 45 degrees with respect to the output of the magnetron. The power output of the magnetron is not substantially reduced.
    Type: Grant
    Filed: January 18, 1983
    Date of Patent: October 30, 1984
    Assignee: Varian Associates, Inc.
    Inventor: William A. Gerard
  • Patent number: 4474831
    Abstract: In a method for reflow of a phosphosilicate glass (PSG) layer applied to a semiconductor wafer, the wafer is placed in a processing chamber in parallel alignment with a planar blackbody source. The chamber is evacuated, and the source rapidly and uniformly heats the PSG layer to a temperature at which plastic flow occurs. The blackbody source provides significant radiation in the 7-10 micron portion of the infrared spectrum. The thermal treatment is typically completed in 8-15 seconds, thereby avoiding impurity redistribution in the semiconductor device.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: October 2, 1984
    Assignee: Varian Associates, Inc.
    Inventor: Daniel F. Downey