Laser-induced front side and back side etching of fused silica with KrF and XeF excimer lasers using metallic absorber layers: A comparison

► We study laser-induced front and back side etching of fused silica with a KrF and a XeF excimer laser. ► Chromium layers as absorber are used. ► The LIFE method allows nm-precision etching with etching depths up to 300 nm. ► The measurement results are compared to the results calculated by a thermal model.