EUV Mirror

Extremely low HSFR

For beyond EUV optics, high-spatial-frequency roughness (HSFR) must be low to improve damage tolerance and prevent scattering. Using our proprietary technology, we can offer extremely low HSFR surfaces characterized by

• RMS down to 0.1 nm and below.
• Free form including off-axis ellipsoid.
• Material from Si, fused silica, CaF₂ and others.
• Qualified by white light interferometer and AFM.

MSFR below 0.10 nm

Roughness in the spatial frequency range of
1/0.01—1 mm^-1 is defined as mid-spatial-frequency roughness (MSFR). MSFR causes unwanted intensity distribution in beam transportation or focusing. We can provide extremely low MSFR surfaces characterized by

• RMS down to 0.1 nm in an area of
  1 × 1 mm².
• Processed by high-spatial-resolution polishing.
• Qualified by white light interferometer.

Our optics are highly regarded in the semiconductor industry for their extremely low MSFR.

LSFR below 3 nm

In EUV and X-ray optics in focusing systems, low spatial frequency roughness (LSFR or “figure error”) is an important factor in achieving small focus sizes. Our free-form optics have extremely low LSFR (best effort: 2—3 nm RMS), which we consider to be the best surface quality in the world.

• RMS down to 2 nm.
• Off-axis ellipsoid, Wolter, and others.
• High-precision enough to use at synchrotron radiation facilities.