Abstract: An R.F. generator for providing power to a load via a transmission line wherein load impedance is automatically matched to the surge impedance of the transmission to provide maximum transfer of energy from the generator to the load. Voltages representative of input power and reflected power are utilized to control a load match circuit to cause load impedance to equal transmission line impedance. Feedback loop means are also provided to maintain net load power at an externally commanded level.

Abstract: A flowmeter system having circuitry defining a path for confining the flow of a fluid medium therethrough, first and second transducers disposed along said flow path for generating and receiving acoustic compression waves in the fluid medium between the transducers, a phase lock loop receiver/transmitter system including a voltage controlled oscillator for adjusting the frequency of the acoustic compression waves to maintain the compression wave length constant, a phase detector for measuring the phase difference of the received acoustic compression waves relative to that transmitted and for producing a sum signal proportional to the sum of the measured phase differences to vary the output of said voltage controlled oscillator, circuitry for producing a difference signal proportional to the difference of the measured phase differences representing the direction and magnitude of the flow of the fluid medium as well as changes in its composition and an active filter in the loop for increasing the loop gain of t

Abstract: A flowmeter system having a device defining a path for confining the flow of a fluid medium therethrough, first and second transducers disposed along said flow path for generating and receiving acoustic compression waves in the fluid medium between the transducers, a phase lock loop transmit/receive system including a voltage controlled oscillator for adjusting the frequency of the acoustic compression waves to maintain the compression wave length constant, a phase detector for measuring the phase difference of the received acoustic compression waves relative to that transmitted and for producing a sum signal proportional to the sum of the measured phase differences to vary the output of said voltage controlled oscillator, circuitry for producing a difference signal proportional to the difference of the measured phased differences representing the direction and magnitude of the flow of the fluid medium as well as changes in its composition, and circuitry for adjusting the phase of the transmit signal during i

Abstract: A double monochromator having a principal stage and a pre-monochromator or first stage that includes a coarse reflecting plane diffraction grating and a concave mirror for converging the object beam on the grating and for imaging the selected band of diffracted light from the grating on the entrance slit of the principal or second stage. The first stage spectral bandwidth is much larger than the second stage, thus permitting use of a grating having a groove spacing approximately ten times that of the second stage grating, and the use of linear wavelength adjusting means. The imaging mirror results in a shorter image and object distance and therefore a smaller convenient instrument.

Abstract: A self-bonding flame spray wire capable of forming a readily grindable coating formed of a sheath of aluminum and a compacted powder core containing a major portion of nickel and stainless steel and a minor portion of aluminum and metal oxide. The core may contain from about 10 to 90 percent, and preferably about 61 percent, by weight nickel, about 10 to 90, and preferably 30, percent by weight stainless steel, from 1 to 10 percent by weight, and preferably 5 percent by weight, aluminum, from 1/4 to 10 percent by weight, and preferably 4 percent by weight, of the metal oxide which may, for example, be cobalt oxide or zirconium oxide, and is most preferably zirconium oxide.

Abstract: A high speed temperature controlled, microcircuit electrometer comprising a preamplifier with a very high resistance feedback resistor and temperature sensor on a substrate which is temperature controlled by a thermo-electric module on which the substrate is mounted and which is held within a very small temperature range by temperature control circuitry. The preamplifier, feedback resistor, temperature sensor and thermo-electric module are all enclosed in a hermetically sealed, dry gas environment, maintained at an essentially constant temperature, to reduce the effects of hostile environments, such as temperature changes, vibration, contamination, and humidity. This electrometer operates at high speed and is highly responsive to small current values such as ion currents generated by ionized gas molecules in a mass spectrometer.

Abstract: A high track density recording head assembly which eliminates cross-talk in high track density recording systems by positioning very thin neutralization heads between each pair of adjacent recording heads. The neutralization heads are provided with air gaps aligned with the gaps in the adjacent heads and have coils wound to develop a polarity opposite to that in the adjacent recording head. The neutralization head flux thus produced cancels the recording head lateral fringing flux that is responsible for recording interference in the adjacent recording tracks.

Abstract: Apparatus for the etching of semiconductor devices which includes, in combination, an etching chamber containing the semiconductor device to be etched, an electrodeless etching plasma forming chamber having an inlet connected to a source of continuously flowing etching gas and having an outlet connected to said etching chamber in fluid flow communication; a helical inductive resonator coupler for coupling a source of R.F.

Abstract: This invention relates to a plasma etching system, which includes a lower flange and a spaced upper flange; a chamber wall mounted between the flanges to form a closed etching chamber; a grounded wafer support plate disposed in said chamber for receiving thereon a wafer to be processed; an electrical insulating element interposed between the chamber wall and the support plate; a sintered or sintered-like porous electrode plate mounted in the chamber in spaced relationship with respect to the wafer; said plate having a gas inlet for receiving a supply of etching gas; circuitry for applying an excitation voltage to this plate, and said chamber having a gas outlet leading to a vacuum source.

Abstract: An apparatus for controlling the volume of flow of a gas. A reference volume has an input conduit connected to the source of gas and an output conduit connected to a utilization device. Valves in the input and output conduits are cyclically controlled to permit pressure in the reference volume to reach a high and then to attain a low. The reference volume pressure is measured twice during each cycle to provide voltages representative of the high and low pressures. Circuit means control the time and duration of operation of the valves to cause the difference between the high and low pressures to equal a predetermined value.

Abstract: In a ring field projection optical system for imaging a mask on a wafer the illumination source has readily adjustable means for obtaining uniform exposure along the length of the arcuate zone of illumination.

Abstract: A flame spraying device including a rocket accelerator wherein a low velocity flame is produced into which a coating material is introduced. At least one rocket accelerator producing a high velocity stream of combustion product gases is positioned relative to the low velocity flame so that the coating material carried thereby is accelerated toward the substrate to be coated. By positioning the rocket relative to the low velocity flame, the dwell time in the low velocity flame can be optimized to produce the best coating of a substrate. The coating quality is also enhanced by the fact that the coating material does not oxidize or cool significantly while in the high velocity stream and by the fact that the coating material strikes the substrate at high speed thereby resulting in high density coating.

Abstract: A target for use in aligning masks used in producing microcircuits which is of a size that can be printed on a microcircuit chip without interfering with the lines thereon, consisting only of lines vertically or diagonally disposed with respect to the image transducer is disclosed. Also disclosed is an automatic system for aligning such targets.

Abstract: An interferometric system for testing a lens comprises a source of light and a beam splitter in the path of the light divides the light into first and second beams. A device is provided for holding the lens to be tested in the first beam. A reflector is disposed in the path of the first beam beyond the lens for reflecting the first beam to the beam splitter. A movable reflector is provided in the path of the second beam for reflecting the second beam to the beam splitter to form a single recombined beam. The movable reflector is displaceable in translation along the axis of the beam it reflects and in rotation about an axis or orthogonal axes in the plane of the movable reflector and perpendicular to the beam axis. The entire recombined beam impinges on a photoelectric detector which, in response thereto, generates an electrical signal representing the complex point spread function of the lens being tested.

Abstract: A flowmeter system for measuring the flow and changes in the velocity of sound due to changes in composition or temperature of a fluid medium in a flow tube including transducers which generate acoustic compression waves in the fluid medium, phase lock loop transmitter/receiver circuitry including device for measuring the difference in phase of the acoustic compression waves transmitted upstream relative to that received and for measuring the phase difference of the acoustic compression waves transmitted downstream relative to that received and producing a sum signal dependent upon the sum of the two measured phase differences, device for producing a difference signal proportional to the difference of the two measured phase differences which provides an output signal representing the direction and magnitude of the measured flow device for automatically adjusting the frequency of the acoustic compression waves so that their wave lengths remains constant, said means for automatically adjusting the frequency inc

Abstract: An automatic focusing system for positioning silicon or other wafer within the focal plane of a photolithographic mask projection system. The position of the wafer is measured at a plurality of points and compared to the position of an optical flat located in the focal plane to provide signals for positioning the wafer at the focal plane of the projection system. The system also includes means for changing the contours of the wafer to cause it to lie in a known plane.

Abstract: A spectrophotometer system has an optical system for transmitting a beam from a source at select wavelengths onto a detector. A plurality of filters are positioned in a tray. A stepper mechanism indexes the tray along a path. A microcomputer controls the stepper mechanism and the optical system. The wavelength is successively changed over a range, the tray is indexed to move a select filter into the beam at a predetermined wavelength and the changing is discontinued during indexing.

Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which a initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.

Abstract: The first element comprises a relatively thin transmissive shell concave toward the front. The second element comprises a mirror concave toward the front. The front surface of the shell may be spherical, and the rear surface aspheric, or vice versa. The central portion of the first element on either the front or back surface is mirrored to form the secondary of the system. Preferably the secondary mirror is on the front of the first element. In one embodiment the second element is also a transmissive shell. In one form of this embodiment the second transmissive shell is aspheric on the front and spherical on the back. In another form it is spherical on the front and aspheric on the back. In both of these forms the primary mirror is located on the back of the second element. In another embodiment the second transmissive element is aspheric on the front and flat on the back; the front surface being mirrored except for the central portion thereof, through which light from the secondary is focused.

Abstract: Method and apparatus for plasma flame-spraying coating material onto a substrate by means of passing a plasma-forming gas through a nozzle electrode, passing an arc-forming current between said nozzle electrode and a rear electrode to form a plasma effluent, introducing spray coating material into the plasma effluent, passing the plasma effluent axially through a wall shroud extending from the exit of said nozzle electrode and forming a hot gas shroud for the plasma effluent at least within the wall shroud. .Iadd.