A monochromatic Fe beam is generated by heated supersonic
expansion of argon seeded with Fe vapor. At a nozzle temperature
of 1930 K and 800 torr argon inlet pressure the Fe beam has an
axial velocity spread of 8% and intensity of 3 × 1015
s−1 sr−1, corresponding to a deposition rate of 10
nm/h at 150 mm from the nozzle. The two-chamber alumina crucibles are
chemically stable for liquid Fe. With 400 mm3 Fe we have
operated for more than 200 hours without reloading. The power
consumption at 1930 K is 750 W. Temperature stability at constant
power (without feedback) is better than 30 K. The source is
intended for deposition of nanostructures by laser focusing of the
Fe beam. The small axial velocity spread virtually eliminates the
increase in focal spot size due to chromatic aberration.