Patent ID: 8426324

Claim:
A method for manufacturing a memory element comprising: forming island-shaped semiconductor layers over a substrate; forming a first insulating film over the island-shaped semiconductor layers; forming gate electrodes each overlapping one of the island-shaped semiconductor layers, over the first insulating film; forming a second insulating film over the gate electrodes; providing a resist over the second insulating film; performing a deflection of a first laser beam by a first deflector so that the first laser beam passes through one of first diffractive optical elements to form a first plurality of laser beams; performing a deflection of a second laser beam by a second deflector so that the second laser beam passes through one of second diffractive optical elements to form a second plurality of laser beams; irradiating the resist with the first and the second plurality of laser beams; and etching the first insulating film and the second insulating film by development of the resist irradiated with the first and the second plurality of laser beams to selectively form contact holes.