摘要 |
A method of laser-marking a semiconductor device involves providing a semiconductor wafer having a plurality of solder bumps formed on contact pads disposed on its active surface. The solder bumps have a diameter of about 250-280 mum. A backgrinding tape is applied over the solder bumps. The tape is translucent to optical images. A backside of the semiconductor wafer, opposite the active surface, undergoes grinding to reduce wafer thickness. The backside of the semiconductor wafer is laser-marked while the tape remains applied to the solder bumps. The laser-marking system including an optical recognition device, control system, and laser. The optical recognition device reads patterns on the active surface through the tape to control the laser. The tape reduces wafer warpage during laser-marking to about 0.3-0.5 mm. The tape is removed after laser-marking the backside of the semiconductor wafer.
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