LASER-INDUCED ETCHING OF SI SURFACES - THE EFFECT OF WEAK BACKGROUND LIGHT

Two different lasers were used to etch patterns on Si surfaces employi ng a thin film cell configuration. A strong, pulsed, 20 W KrF excimer laser was used for etching. A weak, cw, 5 mW HeNe laser provided backg round light. This laser, by itself, was incapable of etching the Si su rface. A substantial enhancement of the laser etching process with bac kground light was observed either when using many pulses or only one U V laser pulse. An even bigger change was observed as a function of the etchant concentration. (C) 1996 American Institute of Physics.