| abstract |
An improved method of laser marking semiconductor wafers is provided wherein undesirable subsurface damage to a silicon semiconductor wafer is avoided while providing a relative improvement in marking speed for a predetermined spot diameter. A laser pulse of a laser beam has a predetermined wavelength, pulse width, repetition rate, and energy. The method further includes irradiating a semiconductor wafer with the pulsed laser beam over a spot diameter to produce a machine readable mark on the semiconductor wafer. The mark has a mark depth. The pulse width is less than about 50 ns, and the step of irradiating irradiates over the spot diameter to produce a mark having a mark depth substantially less than about 10 microns. |