Patents Assigned to ENI
  • Patent number: 6064559
    Abstract: An optical position sensor for a vacuum tuning capacitor employs optic fibers that are positioned adjacent a nut associated with the guide shaft. A threaded lead screw is rotated to lift the nut and move the capacitor from a fully-withdrawn home position to a tuning position. A first fiber has its terminus aligned with the terminus of a second fiber to define a gap. A flag or shutter on the nut is positioned in the gap to block the light path between the fibers when the nut is in the home position, but is out of the gap to allow passage of light otherwise. This produces normally on signaling, giving the position sensor a fail-safe capability. The sensor can be incorporated into a cap or cover of the tuning capacitor.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: May 16, 2000
    Assignee: ENI Technologies Inc.
    Inventor: Richard E. Church, Jr.
  • Patent number: 6046641
    Abstract: A high power grounded-drain source follower RF amplifier circuit employs a high voltage MOSFET. The RF signal at the input is applied with respect to ground via an isolation transformer whose secondary feeds the signal between gate and source. The output is taken from the source with respect to drain, which is grounded. A 13.56 MHz 3 KW power amplifier topology with isolated RF input drive for each MOSFET die uses a pair of kilowatt power transistors or KPTs, in which there are multiple large area MOSFET dies, with the drain regions of the dies being formed over a major portion of the die lower surface. The drain regions are in direct electrical and thermal contact with the conductive copper flange. The source and gate regions are formed on the dies away from the flat lower surface. One or more pairs of multi-chip KPTs can be configured to design stable 2.5 KW, 5 KW and 10 KW RF plasma generators at 13.56 MHz.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: April 4, 2000
    Assignee: ENI Technologies, Inc.
    Inventors: Yogendra K. Chawla, Craig A. Covert
  • Patent number: 6020636
    Abstract: A high-power high-voltage transistor has four or more semiconductor dies mounted in thermal contact on a metal flange. Each die has a flat lower surface with a drain (collector) region formed over at least 80 percent of its lower surface. A gate (base) region and a source (emitter) region are formed respectively on upper surfaces of the die. The drain region is seated in direct electrical and thermal contact with the flange, so that the flange serves as a drain lead for the transistor die. The die has a drain-source breakdown voltage or collector-emitter breakdown voltage) on the order of one kilovolt or higher and an area of one hundred thousand square mils or larger. Molybdenum tabs between the drain (collector) region and the flange protect the die from thermally-induced stresses. The dies can be MOSFET power transistors, bipolar junction transistors or other solid-state devices. An oval lead frame can be employed for connecting to the source regions.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: February 1, 2000
    Assignee: ENI Technologies, Inc.
    Inventor: Gary C. Adishian
  • Patent number: 6020794
    Abstract: An RF plasma system employs frequency tuning to change the frequency of an RF generator within a frequency range to match the impedance of a plasma chamber. Forward power and reflected power magnitudes are obtained from a bidirectional sensor. The ratio of reflected power to forward power is obtained for one frequency, and then the frequency is changed. The tuning algorithm compares the ratio of reflected to forward power at the new frequency with the ratio obtained earlier. If this ratio is smaller, the frequency is changed again in the same direction, but if larger, then the frequency is changed in the other direction. These steps are iterated until the ratio of reflected to forward power reaches a minimum. The tuning algorithm can be implemented in hardware or in software.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: February 1, 2000
    Assignee: ENI Technologies, Inc.
    Inventor: Joseph Wilbur
  • Patent number: 5971591
    Abstract: Plasma process control arrangement controls a plasma generator that provides electrical power to a plasma chamber for an RF or DC plasma process. A sensor system detects operating parameters of the electrical power, including voltage and current levels. A process detection system (pds) controller has inputs coupled to the sensor system to receive the operating parameters, a programmable memory unit for storing a control program to compute an output control signal based on the operating parameters, and a control output coupled to a control input of the plasma generator. An external computer device, includes a monitor, an icon copying device for example, a mouse suitable for drag-and-drop operation, and a memory storing a suitable code-building program for generating a user-selected control program according to user-determined process requirements.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: October 26, 1999
    Assignee: ENI Technologies, Inc.
    Inventors: Daniel F. Vona, Kevin S. Gerrish, Kevin P. Nasman
  • Patent number: 5842154
    Abstract: A fuzzy logic control arrangement is provided for an impedance match network of the type that is typically employed between a source of RF power at a given impedance, e.g., 50 ohms, and a non-linear load whose impedance can vary in magnitude and phase, e.g., an RF plasma. The fuzzy logic controller fuzzifies the phase and the magnitude error signals. The error signals are applied to a fuzzy logic inference function based on a number of fuzzy sets. The values of the error signals enjoy some degree of membership in one or more fuzzy sets. Fuzzy logic rules are applied to the phase and magnitude error signals. In a defuzzification stage, drive signal values are obtained for moving the tuning elements of the variable impedances. The drive signal values are weighted according to respective fuzzy inference functions for which the error signals enjoy membership. Then the weighted drive signal values are combined to produce output drive signals.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: November 24, 1998
    Assignee: ENI Technologies, Inc.
    Inventor: Sean Harnett
  • Patent number: 5810982
    Abstract: Pulses of a positive voltage are superimposed onto negative dc sputtering current that is applied to the target of a dc sputtering process to create a reverse bias. This charges insulating deposits on the target to the reverse bias level, so that when negative sputtering voltage is reapplied to the target, the deposits will be preferentially sputtered away. The reverse bias pulses are provided at a low duty cycle, i.e., with a pulse width of 0.25 to 3 microseconds at a pulse rage of 40 to 200 KHz. This technique reduces or eliminates the sources for arcing. A circuit arrangement for reverse biasing provides the forward (negative) dc sputtering power as a current source, and provides the pulses of reverse (positive) voltage as a voltage source.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: September 22, 1998
    Assignee: ENI Technologies, Inc.
    Inventor: Jeff C. Sellers
  • Patent number: 5770023
    Abstract: An asymmetric bipolar plasma etching process is employed for etching a workpiece positioned within a plasma chamber, to prepare the workpiece for a subsequent coating process. The etching process involves applying a negative high voltage to the workpiece, relative to an anode portion of the chamber. Pulses of a positive voltage are applied to the workpiece at a predetermined pulse width and a predetermined level relative to the anode, so that the applied voltage appears as a train of asymmetric bipolar pulses. The waveform has a major negative-going portion and a minor positive-going portion. The negative-going portion can have a voltage of minus 300 to minus 4,000 volts, and the positive-going pulses can have a voltage of plus 50 to plus 300 volts, and a typical pulse width between about 0.25 and 3 microseconds. The etching process can be followed by a sputter coating process in the same chamber. Another coating technique could also be used.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: June 23, 1998
    Assignee: ENI A Division of Astec America, Inc.
    Inventor: Jeff C. Sellers
  • Patent number: 5770922
    Abstract: An RF probe for a plasma chamber picks up current and voltage samples of the RF power applied to an RF plasma chamber, and the RF voltage and current waveforms are supplied to respective mixers. A local oscillator supplies both mixers with a local oscillator signal at the RF frequency plus or minus about 15 KHz, so that the mixers provide respective voltage and current baseband signals that are frequency shifted down to the audio range. The phase relation of the applied current and voltage is preserved in the baseband signals. These baseband signals are then applied to a stereo, two-channel A/D converter, which provides a serial digital signal to a digital signal processor or DSP. A local oscillator interface brings a feedback signal from the DSP to the local oscillator. The DSP can be suitably programmed to obtain complex Fast Fourier Transforms of the voltage and current baseband samples.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: June 23, 1998
    Assignee: ENI Technologies, Inc.
    Inventors: Kevin S. Gerrish, Daniel F. Vona, Jr.
  • Patent number: 5737169
    Abstract: A protective circuit for a power field effect transistor, e.g., a power MOSFET, employs a diode-switched pickup circuit, a threshold detector, and a timer. The pickup circuit includes a resistor and diode in series, with the diode connected with the MOSFET drain electrode and the resistor connected with the gate driver for the MOSFET gate electrode. A pickup voltage V.sub.1 appears at the junction of the diode and resistor. When the MOSFET is conducting the pickup voltage is the sum of the channel voltage V.sub.ds-on and the diode forward voltage V.sub.f. When the MOSFET is biased OFF, the pickup voltage is zero. The threshold detector compares the pickup voltage with a reference voltage that is offset some predetermined amount from the source electrode voltage. When threshold circuit goes high, the timer circuit provides a time-out or inhibit signal to an inhibit input of the gate driver circuit. Under high load current or high temperature conditions, the drain-source voltage V.sub.
    Type: Grant
    Filed: February 28, 1996
    Date of Patent: April 7, 1998
    Assignee: ENI, A Division of Astec America, Inc.
    Inventor: Jeff C. Sellers
  • Patent number: 5726603
    Abstract: A linear RF power amplifier employs push-pull pairs of high voltage mosfets. A minimum of transformers is employed, with an impedance matching transformer feeding an input balun supplying the input signal in push-pull to the gates of the mosfets. The drains are coupled to balanced legs of an output balun, followed by an output impedance matching transformer. Thermal sensors are employed for control of gate bias and also for control of drain voltage. The temperature sensors are mounted in the air inlet path and on the spreader plate of the heat sink. An aluminum or fiberglass strap is used to press the transistors against the spreader plate thereby ensuring good thermal contact with the transistor dies.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: March 10, 1998
    Assignee: ENI Technologies, Inc.
    Inventors: Yogendra K. Chawla, Leonid Reyzelman
  • Patent number: 5717293
    Abstract: A strike enhancement circuit for a dc power supply, which can be a switched half-bridge supply, creates a high voltage at high impedance to initiate a plasma in a plasma chamber or sputtering chamber. The strike circuit has a plurality of diode bridges that act as full-wave rectifiers or peak detectors. The transformer secondary of the power supply is connected through isolation capacitors to the ac inputs of each of the diode bridges. The dc ports of the diode bridges are stacked in series, and the combined, stacked voltage is applied across the input terminals of the plasma chamber. Each diode bridge also has a storage capacitor connected between the positive and negative dc ports. Positive and negative voltage peaks from the transformer secondary waveform are stored in the storage capacitors. The combined dc outputs applied to the plasma chamber appear as a voltage high enough to initiate a plasma discharge.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: February 10, 1998
    Assignee: ENI Technologies, Inc.
    Inventor: Jeff C. Sellers
  • Patent number: 5651865
    Abstract: Pulses of positive voltage are applied to the target of a dc sputtering process to create a reverse bias. This charges insulating deposits on the target to the reverse bias level, so that when negative sputtering voltage is reapplied to the target, the deposits will be preferentially sputtered away. The reverse bias pulses are provided at a low duty cycle, i.e., with a pulse width of 0.25-3 microseconds at a pulse rate of about 40-100 KHz. This technique reduces sources for arcing during a reactive sputtering process.
    Type: Grant
    Filed: June 17, 1994
    Date of Patent: July 29, 1997
    Assignee: ENI
    Inventor: Jeff C. Sellers
  • Patent number: 5627738
    Abstract: A soft start circuit for a high-power module permits trickle-charging of the capacitor bank prior to power switch actuation, and avoids large current surges or inrush at power up. Positive temperature coefficient thermistor devices, or PTCs are place in shunt across the switch elements or poles of the actuator or other power switch. In a power module that is powered by three-phase AC, the three power conductors are coupled through a three-pole contactor to AC inputs of a polyphase rectifier bridge, which has DC outputs coupled to the capacitor bank and to a load device, such as a high-power RF amplifier. The PTCs are connected, one per pole, in shunt across each pole of the contactor. Alternatively, metallized film capacitors can be employed in lieu of the PTCs.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: May 6, 1997
    Assignee: ENI, A Division of Astec America, Inc.
    Inventors: Vadim Lubomirsky, Jeff C. Sellers
  • Patent number: 5584974
    Abstract: A dc sputtering process applies a pulsating dc voltage in which each cycle includes a pulse portion of negative dc voltage of -300 to -700 volts alternating with a reverse bias (positive) pulse of about +50 to +300 volts. The reverse bias pulse portion will reduce or eliminate sources for arcing in most cases. To combat sticky or persistent arcing, the negative pulse portion is monitored. If, during a window portion of the negative pulse portion, the applied voltage drops into a range characteristic of arcing for two successive cycles, then the applied power is interrupted for a period, e.g., 200 microseconds, and reverse bias is applied. An overvoltage detection and clamping circuit monitors the applied voltage for extreme voltage excursions, and if an overvoltage threshold is exceeded for two successive cycles, the applied power is interrupted. The overvoltage detection and clamping circuit can comprise a string of zener diodes or equivalent voltage limiting devices connected to the applied voltage.
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: December 17, 1996
    Assignee: ENI
    Inventor: Jeff C. Sellers
  • Patent number: 5565737
    Abstract: An aliasing sampler probe for detecting plasma RF voltage and current employs a sampling signal with a sampling rate slower that the RF fundamental frequency selected to produce an aliasing waveform at an aliasing frequency that is several orders of magnitude below the RF fundamental frequency. In one embodiment, the RF power is applied at 13.56 MHz. and sampling pulses have a sampling rate of 2.732 MHz to produce replicas of the RF voltage and current waveforms at an aliasing frequency of about 100 KHz. The aliasing replicas preserve phase and harmonic information with an accuracy that is not available from other sampling techniques.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 15, 1996
    Assignee: ENI - a Division of Astec America, Inc.
    Inventor: Anthony R. A. Keane
  • Patent number: 5488331
    Abstract: A high-power radio-frequency amplifier acts on periodic pulses of RF energy. The bias is controlled for each of a bank of FETs or other amplifier devices that constitutes the main power stage. A sample of bias current is obtained during a blanking period on the front porch of the RF gating period. Quiescent drain current is measured, and stored on a sample/hold circuit. A digital signal processor provides bias values that are sent via a D/A converter to biasing circuits that add the bias levels to the input RF signal. If the bias current is above or below a desired level, the stored bias level is decreased or incremented respectively. A timing control circuit gates the sample/hold circuit and switches in advance of the biasing circuits. The timing control circuit also creates a blanking signal to apply to an attenuator to produce a null region during the first 100 microseconds of the gating signal.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: January 30, 1996
    Assignee: ENI, A Div. of Astec America, Inc.
    Inventors: Anthony R. A. Keane, Bart C. Vandebroek
  • Patent number: 5477188
    Abstract: A linear RF power amplifier employs push-pull pairs of high voltage mosfets. A minimum of transformers is employed, with an impedance matching transformer feeding an input balun supplying the input signal in push-pull to the gates of the mosfets. The drains are coupled to balanced legs of an output balun, followed by an output impedance matching transformer. Thermal sensors are employed for control of gate bias and also for control of drain voltage. The temperature sensors are mounted in the air inlet path and on the spreader plate of the heat sink. An aluminum or fiberglass strap is used to press the transistors against the spreader plate thereby ensuring good thermal contact with the transistor dies.
    Type: Grant
    Filed: July 14, 1994
    Date of Patent: December 19, 1995
    Assignee: ENI
    Inventors: Yogendra K. Chawla, Leonid Reyzelman
  • Patent number: 5451907
    Abstract: A high-power radio-frequency amplifier act on periodic pulses of RF energy. The bias is controlled for each of a bank of FETs or other amplifier devices that constitutes the main power stage. A sample of bias current is obtained during a blanking period on the front porch of the RF gating period. Quiescent drain current is measured, and stored on a sample/hold circuit. A digital signal processor provides bias values that are sent via a D/A converter to biasing circuits that add the bias levels to the input RF signal. If the bias current is above or below a desired level, the stored bias level is decreased or incremented respectively. A timing control circuit gates the sample/hold circuit and switches in advance of the biasing circuits. The timing control circuit also creates a blanking signal to apply to an attenuator to produce a null region during the first 100 microseconds of the gating signal.
    Type: Grant
    Filed: May 16, 1994
    Date of Patent: September 19, 1995
    Assignee: ENI, Div. of Astec America, Inc.
    Inventors: Anthony R. A. Keane, Bart C. Vandebroek
  • Patent number: 5366991
    Abstract: 5-pyrazolecarboxylic acid amide-based insecticide and acaricide compounds of general formula (I): ##STR1## in which: R.sub.1 represents a hydrogen atom, a linear or branched C.sub.1 -C.sub.4 alkyl group or a benzyl group;R.sub.2 represents a hydrogen atom or a linear or branched C.sub.1 -C.sub.4 alkyl group;R.sub.x represents a hydrogen atom, a halogen atom such as chlorine, fluorine or bromine, or a linear or branched C.sub.1 -C.sub.4 alkyl or haloalkyl group; or R.sub.2 and R.sub.x together represent an RHC--(CH.sub.2).sub.n --CH.sub.2 group in which R represents a hydrogen atom or a C.sub.1 -C.sub.3 alkyl group and n is a whole number between 1 and 2;R.sub.3, R.sub.4, R.sub.5 represent, each independently, a hydrogen atom or linear or branched C.sub.1 -C.sub.4 alkyl group;X.sub.1, X.sub.2, X.sub.3 and X.sub.4 represent, each independently, a hydrogen atom or a halogen atom such as chlorine, fluorine or bromine;R.sub.y represents a linear or branched C.sub.3 -C.sub.
    Type: Grant
    Filed: September 27, 1993
    Date of Patent: November 22, 1994
    Assignee: Eni Chem Synthesis S.p.A.
    Inventors: Franco Bettarini, Luigi Capuzzi, Piero La Porta, Sergio Massimini, Franca Reggiori, Giovanni Meazza