Determining the field emitter temperature during laser irradiation in the pulsed laser atom probe

Journal Article · Sat Aug 01 00:00:00 EDT 1981 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.329390· OSTI ID:6345988

Kellogg, G L

Three methods are discussed for determining the field emitter temperature during laser irradiation in the recently developed Pulsed Laser Atom Probe. A procedure based on the reduction of the lattice evaporation field with increasing emitter temperature is found to be the most convenient and reliable method between 60 and 500 K. Calibration curves (plots of the evaporation field versus temperature) are presented for dc and pulsed field evaporation of W, Mo, and Rh. These results show directly the important influence of the evaporation rate on the temperature dependence of the evaporation field. The possibility of a temperature calibration based on the ionic charge state distribution of field evaporated lattice atoms is also discussed. The shift in the charge state distributions which occurs when the emitter temperature is increased and the applied field strength is decreased at a constant rate of evaporation is shown to be due to the changing field and not the changing temperature. Nevertheless, the emitter temperature can be deduced from the charge state distribution for a specified evaporation rate. Charge state distributions as a function of field strength and temperature are presented for the same three materials. Finally, a preliminary experiment is reported which shows that the emitter temperature can be determined from field ion microscope observations of single atom surface diffusion over low index crystal planes. This last calibration procedure is shown to be very useful at higher temperatures (>600 K) where the other two methods become unreliable.

• Research Organization: Sandia National Laboratories, Albuquerque, New Mexico 87185
• DOE Contract Number: DE ACO4-76-DP00789
• OSTI ID: 6345988
• Journal Information: J. Appl. Phys.; (United States), Vol. 52:8
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
TRANSITION ELEMENTS
FIELD EMISSION
ATOMS
CALIBRATION
CRYSTAL LATTICES
ELECTRIC FIELDS
EVAPORATION
HIGH TEMPERATURE
IRRADIATION
LASER RADIATION
LOW TEMPERATURE
MEDIUM TEMPERATURE
METALS
PROBES
PULSES
TEMPERATURE DEPENDENCE
TEMPERATURE MEASUREMENT
VERY LOW TEMPERATURE
CRYSTAL STRUCTURE
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION
PHASE TRANSFORMATIONS
RADIATIONS
360603* - Materials- Properties