Ar ion laserhyphen;assisted chemical etching of Mo foils in air is reported. Etching occurred due to local heating by the focused laser beam which induced the Mo oxidation to form the volatile MoO3at the elevated sample temperature. Holes and slots with slightly tapered walls and a minimum hole diameter of less than 10 mgr;m could be etched in 25hyphen;, 50hyphen;, and 150hyphen;mgr;mhyphen;thick foils. The hole diameters increased with increasing laser power and at any given laser power they decreased with increasing sample thickness. Etchhyphen;rate measurements as a function of the laser power were performed with static and scanned samples. Threshold powers for etching through the Mo foils were found. They increased with increasing sample thickness. Above these thresholds the etch rates increased rapidly with increasing laser power and rates as high asdz/dt=50 mgr;m/s in the static mode anddV/dt=20times;50times;300 mgr;m3/s in the scanning mode were obtained in a 50hyphen;mgr;mhyphen;thick Mo foil under 10hyphen;W laser irradiation. Average sample temperatures as functions of the laser power in the scanning mode of operation where thermal equilibrium exists were measured by the use of optical pyrometry. A model which relates the laser power to the etch rate and temperature of the sample is presented and tested for agreement with the experimental results.
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