Ebara Corporation

Hiroaki Shibue

Taro Takahashi

Shinpei Tokunaga

Hiroto Yamada

Atsushi Abe

Akira Nakamura

Katsuhide Watanabe

Mitsuo Tada

Hiroshi Ota

Toshiki Miyakawa

Yasumasa Hiroo

There is provided a detection signal processing circuit and a detection signal processing method for an eddy current sensor that are less easily influenced by a change in ambient environment than conventional technologies. A detection signal processing apparatus includes a converter configured to convert a first analog signal output by a detection coil into a first digital signal, a converter configured to convert a second analog signal output by a dummy coil into a second digital signal, and a detector which is a digital signal processing circuit configured to detect the first digital signal and the second digital signal.

Detection signal processing apparatus and detection signal processing method for eddy current sensor

An eddy current sensor has an exciting coil and a detection coil. A holding circuit holds reference data indicating a characteristic of an output signal output from the detection coil at a reference state and outputs the reference data at a state other than the reference state. A pseudo signal generating circuit generates and outputs a balance coil pseudo signal corresponding to the output signal output from the detection coil at the reference state from the reference data output from the holding circuit. A bridge circuit, at the state other than the reference state, receives the output signal output from the detection coil and the balance coil pseudo signal and outputs a bridge output signal corresponding to a difference between the output signal and the balance coil pseudo signal as a bridge output signal.

Output signal processing apparatus for eddy current sensor

An eddy current sensor assembly includes an eddy current sensor and an output signal processing circuit that processes an output signal from the eddy current sensor. The output signal processing circuit includes a mixer circuit that accepts the output signal and a signal of the predetermined frequency as input, multiplies the two signals received as input, and outputs an output signal obtained by the multiplication, and a low-pass filter that accepts the output signal output by the mixer circuit as input, cuts a high-frequency signal included in the output signal received as input, and outputs at least a direct-current (DC) signal.

Output signal processing circuit for eddy current sensor and output signal processing method for eddy current sensor

A polishing apparatus capable of acquiring accurate film thickness distribution information is disclosed. The polishing apparatus includes a polishing table, a plurality of film thickness sensors, and a controller. The controller analyzes film thickness distribution information of a substrate while identifying a notch position of the substrate based on the measured film thickness information, and outputs visualization information of the film thickness distribution with the notch position as a reference position.

Polishing apparatus, polishing method and method for outputting visualization information of film thickness distribution on substrate

A magnetic element for strengthening a magnetic field formed in an object and an eddy current sensor using the magnetic field are provided. The eddy current sensor includes a bottom face portion which is a magnetic body, a magnetic core portion provided at the middle of the bottom face portion and a peripheral wall portion provided on the periphery of the bottom face portion. The eddy current sensor further includes an excitation coil disposed on an outer periphery of the magnetic core portion and capable of generating a magnetic field and an excitation coil disposed on an outer periphery of the peripheral wall portion and capable of generating a magnetic field.

Magnetic element and eddy current sensor using the same

An eddy current detection device configured to form a stronger magnetic field in a polishing target and a polishing apparatus employing the same eddy current detection device are provided. An eddy current detection device that can be disposed near a semiconductor wafer on which a conductive film is formed includes a plurality of eddy current sensors. The plurality of eddy current sensors are disposed near to one another. Each of the plurality of eddy current sensors includes a pot core, an exciting coil disposed in the pot core and configured to form an eddy current in the conductive film, and a detection coil disposed in the pot core and configured to detect the eddy current formed in the conductive film.

Eddy current detection device and polishing apparatus

An end-point detection sensordetects an end point of polishing, the end-point detection sensorbeing arranged in a polishing table. The end-point detection sensorhas a pot core. The pot corehas a bottom portion, a magnetic core base portionand a peripheral wall base portion. The end-point detection sensorhas an exciting coil, and a detection coil. The back surfaceof the polishing padhas a spacewhich is arranged at a portion facing the polishing tableand houses a magnetic core extension portionand a peripheral wall extension portion. The magnetic core extension portionand the peripheral wall extension portionextending to the spaceare located in the space

Polishing apparatus

The polishing process includes a first state where an eddy current sensor and a polishing target object do not face each other and a second state where the eddy current sensor and the polishing target object face each other. The method of correcting a film thickness measurement value includes obtaining a first measurement signal (Xout, Yout) output from the eddy current sensor in the first state (step S), computing a correction value (&#x394;X, &#x394;Y) on the basis of the obtained first measurement signal and a reference signal (Xsd, Ysd) set in advance, obtaining a second measurement signal (X, Y) output from the eddy current sensor in the second state (step S), and correcting the obtained second measurement signal on the basis of the computed correction value while the polishing process is being performed (step S).

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Tokyo, Japan

Hiroaki Shibue