Patent ID: 11874229
Assignee: ONTO INNOVATION INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 16:
17. An optical metrology device for Raman spectroscopy, comprising:
means for generating a first excitation light beam having a first wavelength;
means for generating a second excitation light beam having a second wavelength;
means for partially reflecting the first wavelength and transmitting the second wavelength with to propagate the first excitation light beam and the second excitation light beam along a same optical axis that is incident on a sample, and receiving a first Raman response emitted from the sample in response to the first excitation light beam, a second Raman response that is emitted from the sample in response to the second excitation light beam, the first excitation light beam reflected from the sample, and the second excitation light beam reflected from the sample, and directing the first Raman response and the second Raman response together without the first excitation light beam reflected from the sample to be spectrally measured;
means for spectrally measuring the first Raman response and the second Raman response that are emitted from the sample, wherein the means for spectrally measuring comprises a first spectrometer that receives the first Raman response that is emitted from the sample in response to the first excitation light beam, and a second spectrometer that receives the second Raman response that is emitted from the sample in response to the second excitation light beam; and
a means for separating the first Raman response and the second Raman response, directing the first Raman response towards the first spectrometer, and directing the second Raman response towards the second spectrometer.