20‐&mgr;m‐wide, 1‐mm‐long, single‐crystal Si films on SiO2have been produced using a cw Ar laser beam split by a birefringent quartz plate. The single‐scan recrystallized region width has been widened by multiple beam splitting. The resultant single‐crystal region obtained by multiple scan from the seed is a 90‐&mgr;m‐wide and 100‐&mgr;m‐long area with rare grain boundaries. This split beam method uses the stable and highly efficient TEM00mode and needs no prepatterned antireflection layers.