| 摘要 |
The closed loop embodiment includes a pulsed laser controller to selectively operate a pulsed laser in a lower-power probe mode or a higher power operational mode. In lower-power probe mode, values of eT (total radiation energy flooding ICs on a silicon wafer), er (fraction of eT specularly reflected), es (fraction of eT scattered) and es (fraction of eT transmitted through wafer) are obtained. A value for ea (fraction of eT absorbed wafer) is calculated i.e. ea=eT-(er+es+et), and ea used by pulsed laser controller with pulsed laser in higher power operational mode to adjust pulsed laser fluence over the duration of a pulse to provide flooding radiation energy sufficient to melt an amorphized silicon surface layer beneath radiation-absorbent material, yet insufficient to melt crystalline silicon or ablate radiation-absorbent material. Open loop embodiment substitutes a separate low-power probe laser for operation in lower-power probe mode.
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