Lam Research Corporation

Tuan Ngo

Brett C Richardson

Michael S Barnes

Andras Kuthi

Rongping Wang

James C Vetter

Greg Eilenstine

Stephen Hwang

Tuqiang Q Ni

Chung-Ho Huang

Farro F Kaveh

John Patrick Holland

Alan M Schoepp

Anthony Le

Andrew Lui

Robert Knop

Christopher H Olson

Connie Lam

Steven Salkow

Ni Tuqiang

Apparatus and methods are provided for monitoring a pulsed RF bias signal applied to a chuck in a processing chamber. One method includes operations for detecting voltage values of individual pulses of the pulsed RF bias voltage, and for determining the time for sampling the value of each individual detected pulse. At the sampling time for each pulse, a particular voltage value of the respective individual detected pulse is sampled and the particular voltage value is held. Each particular voltage value represents a characteristic peak-to-peak voltage value of each individual detected pulse. A feedback signal representing the characteristic peak-to-peak voltage value for a voltage envelope of one of the individual detected pulses is generated, and the voltage of the pulsed RF bias voltage signal applied to the chuck is adjusted according to a difference between the feedback signal and a desired voltage value of the pulsed RF bias voltage signal.

Measuring and controlling wafer potential in pulsed RF bias processing

Apparatus and methods are provided to detect and control a voltage potential applied in a plasma chamber for processing a semiconductor wafer. The plasma chamber includes circuitry for monitoring and adjusting a pulsed RF bias voltage signal to be applied to a chuck in the plasma chamber, where the chuck is configured to mount the wafer for processing. The circuitry includes an RF bias voltage detector for detecting individual pulses of the pulsed RF bias voltage signal applied to the chuck. A timing circuit is provided for determining a time for sampling each of the individual detected pulses and a sample and hold circuit. The sample and hold circuit is triggered at the sampling time for sampling each of the individual detected pulses to determine and hold a voltage value representing a peak peak-to-peak voltage value of each individual detected pulse, and the sample and hold circuit is configured to provide a feedback signal representing the peak peak-to-peak voltage value of at least one of the detected pulses. Further included is a feedback circuit for adjusting the voltage of the pulsed RF bias voltage signal applied to the chuck according to a difference between the feedback signal and a desired voltage value of the RF bias voltage signal.

Methods of and apparatus for measuring and controlling wafer potential in pulsed RF bias processing

A central controller for use in a semiconductor manufacturing equipment integrates a plurality of controllers with an open architecture allowing real-time communication between the various control loops. The central controller includes at least one central processing unit (CPU) executing high level input output (i/o) and control algorithms and at least one integrated i/o controller providing integrated interface to sensors and control hardware. The integrated i/o controller performs basic i/o and low level control functions and communicates with the CPU through a bus to perform or enable controls of various subsystems of the semiconductor manufacturing equipment.

Integrated electronic hardware for wafer processing control and diagnostic

A process chamber with a computer system that controls the process chamber is connected to one or more spectrometers. The spectrometers may be part of an interferometer or may be an optical emission spectrometer. The spectrometers may be CCD or photodiode arrays of 2,048 elements. An input board forms part of the computer system and is directly connected to the spectrometers. The input board provides data from the spectrometers to dual port memory, which is directly accessible to the CPU of the computer system. The use of a state machine and adder on the input board allows computation and placement of the data from the spectrometers on to the dual port memory, so that the CPU is not needed for such placement.

Integrated full wavelength spectrometer for wafer processing

Disclosed is a method and device for compensating a bias voltage on a wafer disposed over an electrostatic chuck in a processing chamber of a plasma processing system. The plasma processing system includes an electrostatic and RF power supplies that are coupled to the electrostatic chuck. The bias compensation device includes a voltage converter, a storage unit, and a voltage adjusting circuitry. The voltage converter is coupled to the electrostatic chuck for detecting a voltage Vpp of the electrostatic chuck. The voltage converter converts the detected voltage to a lower voltage Vref. The storage unit stores a predetermined slope and a predetermined offset of a calibration curve, which is derived by fitting a plurality of wafer bias voltages as a function of electrostatic chuck voltages.

Method and device for compensating wafer bias in a plasma processing chamber

Variable reactances of a matching network connected between an r.f. source and a plasma load of a vacuum plasma chamber processing a workpiece are varied so a tendency of the plasma to change in an unstable manner which can adversely affect processing of the workpiece is avoided while matching is approached. The plasma tendency to change in an unstable manner is detected by monitoring an electrical parameter resulting from r.f. current flowing between the source and load via the network. The parameter can be (1) statistically based, e.g. variance of percent delivered power, or (2) amplitude modulation in one or both of the 2-20 kHz and 50-200 kHz ranges.

Method of and apparatus for minimizing plasma instability in an rf

A gas in a vacuum plasma processing chamber is ignited to a plasma by subjecting the gas to an r.f. field derived from an r.f. source having a frequency and power level sufficient to ignite the gas into the plasma and to maintain the plasma. The r.f. field is supplied to the gas by a reactive impedance element connected via a matching network to the r.f. source. The matching network includes first and second variable reactances that control loading of the source and tuning a load, including the reactive impedance element and the plasma, to the source. The value of only one of the reactances is varied until a local maximum of a function of power coupled between the source and the load is reached. The value of only the other reactance is varied until a local maximum of the function is reached. The two varying steps are then repeated as necessary.

Method of and apparatus for igniting a plasma in an r.f. plasma processor

Method of and apparatus for minimizing plasma instability in an RF

An r.f. field is supplied by a reactive impedance element to a plasma in a vacuum plasma processing chamber. The element and source are connected via a matching network including first and second variable reactances that control loading of the source and tuning a load, including the reactive impedance element and the plasma, to the source. The values of the first and second variable reactances are changed to determine the amount the first variable reactance is to change for each unit change of the second variable reactance to attain the best match between the impedances seen looking into and out of output terminals of the r.f. source. Then the values of the first and second variable reactances are varied simultaneously based on the determination until the best impedance match between the impedances seen looking into and out of output terminals of the r.f. source is attained.

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Milpitas, CA, United States of America

Tuan Ngo