Laser and Laser-Liquid Composite Etching of Si Wafers

摘要

The effect of laser etching in air and laser-liquid composite etching on Si wafers with a Nd:YAG laser and water was studied with equivalent laser operating parameters. The results show that the depth and width of the etched grooves in the laser-liquid composite processing were smaller than those obtained when laser processing in air; moreover the large amounts of slag, recast layer and microcracks typical with laser processing Si in air were eliminated when processing with the laser-liquid composite. This was found to be due to the good cooling effect of the liquid can reduce the accumulation of laser heat in the processing area and the molten material is discharged from the groove through the impacting of the liquid, thereby improving the processing quality. The results of the research demonstrate that the laser-liquid composite processing technology can effectively reduce the defects in traditional laser processing in air.

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