Gas immersion laser doping

Gas Immersion Laser Doping is a method of doping a semiconductor material like Silicon.

Example: Doping Silicon with Boron

A thin Silicon wafer is immersed in Boron gas while a pulsed laser repeatedly melts and cools the wafer. The Boron atoms in the gas diffuse into the molten parts of the Silicon and stay there when the Silicon solidifies, thus producing a Silicon wafer with Boron impurities. The resultant material is a P-type semiconductor.

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