Multiphoton ionization followed by time-of-flight mass spectroscopy of sputtered neutrals

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6460917

Pellin, M J; Young, C E; Gruen, D M

Multiphoton ionization (MPI) by pulsed, tunable lasers provides a sensitive means for detection of neutral atoms. This resonant MPI technique can access all atomic states including ground and metastable levels. The MPI technique permits detailed sputtering data to be obtained with minimal target damage. Velocity and angular distributions can be obtained for each energy level of every sputtered species. Two types of experimental configuration have been employed. In one method, the photoionized atoms are allowed to strike a spatially resolved detector near the target, with extraction fields that preserve the angular distribution information. Velocity information is obtained by time-of-flight (TOF). This method is most suitable for majority species in the sputtered flux. In the case of minority species (either very dilute surface constituents or highly excited states produced), additional noise reduction is necessary. A suitable configuration involves extraction of the photoions into a sector-field TOF mass spectrometer. In standard, isochronous operation, energy and angular spreads at the point of ionization are compensated in flight to produce sharp TOF mass spectra. Noise sources (photons, metastable and scattered atoms) escaping through transparent grids are strongly suppressed. Angular distributions can be mapped. Velocity data can be obtained.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6460917
• Report Number(s): CONF-870588-2; ON: DE87011455
• Country of Publication: United States
• Language: English

Related Subjects

656003* -- Condensed Matter Physics-- Interactions between Beams & Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHARGED PARTICLES
ELECTROMAGNETIC RADIATION
ELEMENTS
EVEN-EVEN NUCLEI
INTERMEDIATE MASS NUCLEI
ION IMPLANTATION
IONIZATION
IONS
IRON
IRON 56
IRON IONS
IRON ISOTOPES
ISOTOPES
LASER RADIATION
MASS SPECTROSCOPY
MEASURING INSTRUMENTS
METALS
NUCLEI
PHOTOIONIZATION
RADIATIONS
SEMIMETALS
SILICON
SPECTROMETERS
SPECTROSCOPY
SPUTTERING
STABLE ISOTOPES
TIME-OF-FLIGHT SPECTROMETERS
TRANSITION ELEMENTS