Optical polarization inspection device and method

1. An inspection apparatus for inspecting a measurement target, the inspection apparatus comprising:

a light output unit comprising a first light source configured to output first light having a first wavelength and a second light source configured to output second light having a second wavelength different from the first wavelength;

a magneto-optical crystal having a reflection surface configured to reflect the first light, the reflection surface being arranged facing the measurement target;

a light detection unit comprising a first light sensor configured to detect the first light and a second light sensor configured to detect the second light; and

a light guide optical system comprising a plurality of optical elements and configured to guide the first light and the second light toward the magneto-optical crystal and the measurement target and guide the first light reflected by the magneto-optical crystal and the second light reflected by the measurement target toward the light detection unit,

wherein the light guide optical system comprises an optical path switching element configured to perform switching between optical paths of the plurality of optical elements so that the first light and the second light are selectively incident on the light detection unit,

wherein the light guide optical system comprises a polarization control element configured to guide one polarized component of the first light to the light detection unit,

wherein the optical path switching element comprises a galvanomirror configured to switch between the optical paths by adding a first offset or a second offset to a central angle of a scanning range of the galvanomirror,

wherein the galvanomirror is configured to scan the first light to the magneto-optical crystal, and

wherein the galvanomirror is configured to add the first offset if the first light is output from the light output unit, and add the second offset if the second light is output from the light output unit.

2. The inspection apparatus according to claim 1 , wherein the light guide optical system further comprises a polarization control element configured to guide the other polarized component of the first light to the light detection unit.

3. The inspection apparatus according to claim 1 , wherein the light guide optical system comprises a polarization control element configured to guide one polarized component of the second light to the light detection unit.

4. The inspection apparatus according to claim 1 , wherein the optical path switching element comprises a Faraday rotator and a wavelength plate.

5. The inspection apparatus according to claim 4 ,

wherein the light guide optical system is configured to comprise a dichroic mirror, and

wherein the dichroic mirror is arranged in a stage previous to the polarization control element.

6. The inspection apparatus according to claim 1 , wherein the optical path switching element comprises a dichroic mirror.

7. The inspection apparatus according to claim 1 , wherein the optical path switching element comprises an optical mirror.

8. The inspection apparatus according to claim 1 , wherein the measurement target is a semiconductor device.

9. The inspection apparatus according to claim 1 , wherein the first wavelength is shorter than the second wavelength.

10. An inspection method of inspecting a measurement target by using a magneto-optical crystal arranged facing the measurement target, the inspection method comprising the step of:

guiding first light having a first wavelength and second light having a second wavelength different from the first wavelength toward the magneto-optical crystal and the measurement target through a light guide optical system and detecting the first light and the second light reflected by the magneto-optical crystal or the measurement target,

wherein the step comprises the steps of:

outputting the first light from a first light source of a light output unit and detecting the first light in a first light sensor of a light detection unit via the light guide optical system;

selectively performing switching between optical paths of the light guide optical system so that the second light is incident on the light detection unit; and

outputting the second light from a second light source of the light output unit and detecting the second light in a second light sensor of the light detection unit via the light guide optical system,

wherein selectively performing switching between optical paths of the light guide optical system includes adding a first offset or a second offset to a central angle ofa scanninn rane of a galvanomirror.