BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a charged particle beam apparatus.

2. Description of the Related Art

Charged particle beam apparatuses such as electron microscopes and ion microscopes are used in observation of various samples having a fine structure. For example, for the purpose of process control on a manufacturing process of semiconductor devices, a scanning electron microscope that is one of the charged particle beam apparatuses is used in measurement of dimensions of a semiconductor device pattern formed on a semiconductor wafer serving as a sample, defect inspection of the semiconductor device pattern, or the like.

A method known as one of the sample analysis methods using an electron microscope is to form a potential contrast image from secondary electrons obtained through application of an electron beam to a sample and evaluate electrical resistance of an element formed on the sample on the basis of analysis of the potential contrast image.

For example, JP 2003-100823 A discloses a method for identifying a defect by calculating an electrical resistance value from a potential contrast. JP 2008-130582 A discloses a method for predicting characteristics of a defect in an electric resistance value or the like by creating, as an equivalent circuit, a netlist that describes information on electrical characteristics and connectivity of circuit elements from a potential contrast.

SUMMARY OF THE INVENTION

For inspection and measurement of semiconductor devices, it is required that a defect in electrical characteristics of the devices in a manufacturing process be detected. However, with the techniques disclosed in JP 2003-100823 A and JP 2008-130582 A, it is difficult to estimate the electrical characteristics with consideration given to interactions between a plurality of the devices using design data and inspection measurement data. Further, when the electrical characteristics are estimated using a plurality of apparatuses, an error may occur in the estimation result between apparatuses.

Therefore, an object of the present invention is to reduce an error in charged particle beam application result of a sample between apparatuses.

The following is a brief description of the summary of a primary aspect of the invention disclosed herein.

A charged particle beam apparatus according to a primary aspect of the present invention includes a database configured to store a to-be-used-in-calculation device model for use in estimation of a circuit of a sample or correction sample and an optical condition under which a charged particle beam is applied to the sample or the correction sample, a charged particle beam optical system configured to control the charged particle beam applied to the sample or the correction sample under the optical condition, a detector configured to detect secondary electrons emitted from the sample or the correction sample excited by the application of the charged particle beam and output a detection signal based on the secondary electrons, and a computing unit configured to generate a to-be-used-in-computation netlist on the basis of the to-be-used-in-calculation device model corresponding to the correction sample, estimate, on the basis of the to-be-used-in-computation netlist and the optical condition, a first application result when the charged particle beam is applied to the correction sample under the optical condition, compare the first application result with a second application result based on the detection signal when the charged particle beam is applied to the correction sample under the optical condition, and correct the optical condition when the first application result and the second application result differ from each other.

The following is a brief description of an effect obtained by the primary aspect of the invention disclosed herein.

That is, according to the primary aspect of the present invention, it is possible to reduce an error, between apparatuses, in result of charged particle beam application to a sample.

