Abstract The surface morphology of silicon solar cells irradiated with KrF excimer laser pulses (λ = 248 nm, τ = 20 ns) was investigated below the experimentally observed melting threshold fluence (Fth) of 0.47 J/cm2 (±20%). At laser fluences of 0.23–0.48 J/cm2 (equivalent to 0.48Fth to 1.0Fth), nanodot structures with a height and width of approximately 60–120 nm were periodically formed with an interdot spacing similar to the laser wavelength. The observed nanodot density (29 dots/μm2) was higher than that previously obtained at longer wavelengths. Furthermore, crystallinity analysis by micro-Raman spectroscopy revealed a Raman shift of 519.56 cm−1 after irradiation (N = 1500 pulses), compared with 518.27 cm−1 prior to irradiation. A laser fluence of 0.41 J/cm2 (= 0.87Fth) was found to induce compressive stress on the silicon solar cell surface.