US 8,525,537 B2 · Method and apparatus for probe contacting

Abstract

There is provided a method and a device for accurately detecting the contact of a mechanical probe with a contact object. The contact detecting device comprises a mechanical probe movable for being in contact with a contacted object, a charged particle beam source which generates a charged particle beam applied to the contacted object, a detector for detecting secondary particles or reflected particles from the contacted object, a calculating device which calculates, from a detection signal from the detector, a feature quantity of a shadow of the mechanical probe projected on the contacted object, and a control device which controls the operation of the mechanical probe. The calculating device calculates, as the feature quantity of the shadow of the mechanical probe, a shadow depth S(x, y), and obtains an evaluation value J(z), showing a distance between the contacted object and the mechanical probe, based on the shadow depth S(x, y).

Claims20

Dependent claims

A contact detecting device, comprising a mechanical probe movable for being in contact with an object to be contacted, a charged particle beam source which generates a charged particle beam to be applied to the object to be contacted, a detector for detecting secondary particles or backscattered particles from the object to be contacted, a calculating device which calculates, from a detection signal from the detector, a feature quantity of a shadow of the mechanical probe projected on the object to be contacted, and a control device which controls the operation of the mechanical probe, wherein:

the calculating device calculates a shadow density S(x, y) as the feature quantity of the shadow of the mechanical probe, the shadow density S(x, y) representing a deviation of brightness Iz(x, y) at a pixel position (x, y) of an observed image when the mechanical probe is provided with respect to brightness I0(x, y) at the pixel position (x, y) of the observed image when the mechanical probe is not provided, and obtains an evaluation value J(z) based on the shadow density S(x, y), the evaluation value J(z) representing a distance between the object to be contacted and the mechanical probe.

A charged particle beam system, comprising a charged particle beam source generating a charged particle beam, a sample table supporting a sample, a mechanical probe used in an operation of cutting out a minute sample piece from the sample, a gas assisted gun used in a deposition operation, a detector which is used for detecting secondary particles or backscattered particles from an object to be contacted with which the mechanical probe is in contact, a calculating device which calculates, from a detection signal from the detector, a feature quantity of a shadow of the mechanical probe projected on the object to be contacted, and a control device controlling the operation of the mechanical probe;

wherein the calculating device calculates a shadow density S(x, y) as the feature quantity of the shadow of the mechanical probe, the shadow density S(x, y) representing a deviation of brightness Iz(x, y) at a pixel position (x, y) of an observed image when the mechanical probe is provided with respect to brightness I0(x, y) at the pixel position (x, y) of the observed image when the mechanical probe is not provided, and obtains an evaluation value J(z) based on the shadow density S(x, y), the evaluation value J(z) representing a distance between the object to be contacted and the mechanical probe.

A contact detecting method of detecting a contact between an object to be contacted and a mechanical probe, comprising the steps of:

moving the mechanical probe toward the object to be contacted;
applying a charged particle beam to the object to be contacted;
detecting secondary particles or backscattered particles from the object to be contacted;
calculating a shadow density S(x, y) from a detection signal of the secondary particles or the backscattered particles, the shadow density S(x, y) representing a deviation of brightness Iz(x, y) at a pixel position (x, y) of an observed image when the mechanical probe is provided with respect to brightness I0(x, y) at the pixel position (x, y) of the observed image when the mechanical probe is not provided;
obtaining an evaluation value J(z) based on the shadow density S(x, y), the evaluation value J(z) representing a distance between the object to be contacted and the mechanical probe;
and
detecting the contact of the mechanical probe to the object to be contacted by the evaluation value J(z).

4 more elements

Dependencies are inferred from the claim text.

Method and apparatus for probe contacting

Life of this patent

Method and apparatus for probe contacting

Life of this patent

Abstract

Claims20