Flash evaporation of compounds with a pulsed-discharge CO(2) laser.
Pulsed laser radiation at 10.6 microm has been used to evaporate a number of compounds chosen for their difficulty of evaporation with conventional techniques. An average laser power of 8 W, pulsed at 50 Hz with a 1-msec duration, has been found sufficient to obtain useful evaporation rates for Al(2)O(3) and other highly refractory materials. For easily decomposed materials such as CdS and ZnS, comparison of cw and pulsed evaporation through measurement of optical and photoconductive film properties consistently indicates higher stoichiometry in pulsed evaporation, as well as higher refractive index. The dynamics of film growth during a single laser pulse has been studied by means of a unique thickness monitor.
Calí
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C
Daneu
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Orioli
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A
Riva-Sanseverino
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