Defect inspection device

A defect inspection device using differential interference contrast that inspects a specimen using light, the defect inspection device comprising:

• a light source configured to emit a light beam;
• a polarizing beam splitter configured to split the light beam into a first beam and a second beam which are polarized and orthogonal to each other;
• a sensor configured to detect a signal from the first beam and the second beam reflected from the specimen;
• and
• a processing processor configured to process the signal detected by the sensor, the processing processor being configured to:
• receive a signal string obtained based on information in at least one dimension around a measured point to be measured on the specimen;
• filter the information from the signal string to extract a low-frequency component;
• determine a phase correction for the sensor based on the low-frequency component, wherein the phase correction corrects a phase difference between the first beam and the second beam, and interference signals having different polarization are detected using the sensor;
• generate corrected interference signals based on the phase correction;
• and
• generate shape information on a specimen surface of the specimen by signal processing the corrected interference signals using the low-frequency component;
• and
• the defect inspection device further includes a polarizer configured to adjust a polarization angle of a beam input to the sensor based on the phase correction.

A defect inspection device using differential interference contrast that inspects a specimen using light, the defect inspection device comprising:

• a light source configured to emit a light beam;
• a polarizing beam splitter configured to split the light beam into a first beam and a second beam which are polarized and orthogonal to each other;
• a sensor configured to detect a signal from the first beam and the second beam reflected from the specimen;
• a processing processor configured to process the signal detected by the sensor and determine a phase correction for the sensor, wherein the phase correction corrects a phase difference between the first beam and the second beam, wherein the processing processor is configured to:
• receive a signal string obtained based on information in at least one dimension around a measured point to be measured on the specimen;
• filter the information from the signal string to extract a low-frequency component;
• determine the phase correction for the sensor based on the low-frequency component, wherein the phase correction corrects the phase difference between the first beam and the second beam, and interference signals having different polarization are detected using the sensor;
• generate corrected interference signals based on the phase correction;
• and
• generate shape information on a specimen surface of the specimen by signal processing the corrected interference signals using the low-frequency component;
• and
• a specimen stage on which the specimen is placed, wherein
• the sensor is a line sensor in which light receiving elements are one-dimensionally arranged at a predetermined pixel pitch, and
• the specimen stage is driven in a first direction and a second direction, one point on a specimen surface of the specimen is overlapped and scanned at least twice in the first direction, and a scanning pitch in the second direction is a non-integer multiple of a pixel pitch of the sensor.

A defect inspection device using differential interference contrast that inspects a specimen using light, the defect inspection device comprising:

• a light source configured to emit a light beam;
• a polarizing beam splitter configured to split the light beam into a first beam and a second beam which are polarized and orthogonal to each other;
• a sensor configured to detect a signal from the first beam and the second beam reflected from the specimen;
• and
• a processing processor configured to:
• receive a signal string obtained based on information in at least one dimension around a measured point to be measured on the specimen;
• filter the information from the signal string to extract a low-frequency component;
• determine a phase correction for the sensor based on the low-frequency component, wherein the phase correction corrects a phase difference between the first beam and the second beam, and interference signals having different polarization are detected using the sensor;
• generate corrected interference signals based on the phase correction;
• and
• generate shape information on a specimen surface of the specimen by signal processing the corrected interference signals using the low-frequency component.