Inspection device and inspection method

An inspection device, comprising circuitry configured to:

• acquire a first characteristic signal indicating electrical properties of an inspection target region of an object to be inspected while applying a test voltage or a test current to the inspection target region;
• generate a first noise signal including noise included in the test voltage or the test current applied to the inspection target region;
• perform filtering on the first noise signal using a filter;
• modify a parameter of the filter in such a manner that a difference between noise included in the first characteristic signal and noise included in the first noise signal after the filtering is reduced;
• acquire a second characteristic signal indicating electrical properties of the inspection target region while applying the test voltage or the test current to the inspection target region and irradiating the inspection target region with a beam;
• generate a second noise signal including noise included in the test voltage or the test current applied to the inspection target region;
• perform filtering on the second noise signal using the filter with the modified parameter;
• perform a noise reduction to noise included in the second characteristic signal using the second noise signal on which the filtering has been performed;
• and
• output the second characteristic signal after the noise reduction has been performed as information for detecting an abnormal portion in the inspection target region.

An inspection method, comprising:

• acquiring a first characteristic signal indicating electrical properties of an inspection target region of an object to be inspected while applying a test voltage or a test current to the inspection target region;
• generating a first noise signal including noise included in the test voltage or the test current applied to the inspection target region;
• performing filtering on the first noise signal using a filter;
• modifying a parameter of the filter in such a manner that a difference between noise included in the first characteristic signal and noise included in the first noise signal after the filtering is reduced;
• acquiring a second characteristic signal indicating electrical properties of the inspection target region while applying the test voltage or the test current to the inspection target region and irradiating the inspection target region with a beam;
• generating a second noise signal including noise included in the test voltage or the test current applied to the inspection target region;
• performing filtering on the second noise signal using the filter with the modified parameter;
• performing a noise reduction to noise included in the second characteristic signal using the second noise signal on which the filtering has been performed;
• and
• outputting the second characteristic signal after the noise reduction has been performed as information for detecting an abnormal portion in the inspection target region.