High-energy 110-fs pulses of a KrF excimer laser system were spectrally broadened by self-phase modulation in a neon-filled hollow fiber and subsequently compressed by a grating pair. In this way, 25-fs pulses with energies as high as 200 microJ were generated at 248 nm. The pulses were characterized by an all-reflective single-shot transient grating frequency-resolved optical gating.