Patent ID: 11946809
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Optics (Instruments)
Classification: CPC G  H | IPC G

Claim 18:
19. A method of fabricating a semiconductor device, the method comprising:
linearly polarizing incident light on a measurement target;
polarizing reflected light by reflecting light from the measurement target;
filtering the reflected light that is polarized; and
detecting the reflected light by receiving the reflected light,
wherein the incident light includes first incident light and second incident light, a phase of the first incident light being different from a phase of the second incident light,
wherein the filtering of the reflected light comprises selectively filtering a signal of a modulation frequency f of a photoelastic modulator and a signal of a frequency 2f, which is twice the modulation frequency f of the photoelastic modulator,
wherein the detecting of the reflected light comprises receiving reflectivity information of the reflected light,
wherein the detecting comprises acquiring a phase difference of frequencies of the reflected light,
wherein each of a polarization axis of the linearly polarized light and a polarization axis of reflected light that is polarized changes based on the measurement target, and
wherein the detecting comprises acquiring differential values of a ratio of amplitudes of frequencies of the reflected light and the phase difference of frequencies of the reflected light in relation to time.