Lithography
What is the wavelength of the light used in KrF excimer laser lithography?
- AAbout 13.5 nm
- BAbout 193 nm
- CAbout 248 nm
Show answer and explanation
Answer: C. About 248 nm
The KrF (krypton fluoride) excimer laser has a wavelength of about 248 nm and has been used since the late 1990s. Wavelengths then shortened to 193 nm with ArF excimer lasers and further to 13.5 nm with EUV.
- A. About 13.5 nm is the EUV wavelength.
- B. About 193 nm is the ArF excimer laser wavelength.
- C. Correct. KrF is about 248 nm.