Production and characterization of highly intense and collimated cluster beams by inertial focusing in supersonic expansions

Citation
P. Piseri et al., Production and characterization of highly intense and collimated cluster beams by inertial focusing in supersonic expansions, REV SCI INS, 72(5), 2001, pp. 2261-2267
Citations number
35
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement
Journal title
REVIEW OF SCIENTIFIC INSTRUMENTS
ISSN journal
00346748 → ACNP
Volume
72
Issue
5
Year of publication
2001
Pages
2261 - 2267
Database
ISI
SICI code
0034-6748(200105)72:5<2261:PACOHI>2.0.ZU;2-E
Abstract
Intense and collimated supersonic cluster beams have been produced by explo iting inertial focusing effects. To this goal we have developed and tested a novel focusing nozzle (focuser). Using this device with a pulsed micropla sma cluster source we have obtained cluster beams with a divergence of 10 m rad and average densities of 3x10(10) atoms/cm(3) (2x10(12) atoms/cm(3) pul sed) corresponding to deposition rates of 2 nm/s at 300 mm distance from th e source nozzle. With a focusing nozzle cluster thermal relaxation and mass distribution in a supersonic expansion can be controlled. We have measured the cluster transverse velocities, with extremely high precision, by chara cterizing the cluster beam deposition on a substrate by an atomic force mic roscope. Besides the relevance for the understanding of relaxation processe s in expanding jets, the inertial focusing of clusters has several importan t consequences for the synthesis of nanostructured films with controlled st ructure and for all the experimental techniques requiring intense and colli mated cluster beams. Due to its simplicity the focusing nozzle presented he re can be used with a wide variety of cluster sources. (C) 2001 American In stitute of Physics.