Optimizing Atom Probe Analysis with Synchronous Laser Pulsing and Voltage Pulsing.
Atom probe has been developed for investigating materials at the atomic scale and in three dimensions by using either high-voltage (HV) pulses or laser pulses to trigger the field evaporation of surface atoms. In this paper, we propose an atom probe setup with pulsed evaporation achieved by simultaneous application of both methods. This provides a simple way to improve mass resolution without degrading the intrinsic spatial resolution of the instrument. The basic principle of this setup is the combination of both modes, but with a precise control of the delay (at a femtosecond timescale) between voltage and laser pulses. A home-made voltage pulse generator and an air-to-vacuum transmission system are discussed. The shape of the HV pulse presented at the sample apex is experimentally measured. Optimizing the delay between the voltage and the laser pulse improves the mass spectrum quality.
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Lu
L
Zhao
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Antoine
A
Normand
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Jonathan
J
Houard
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Ivan
I
Blum
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Fabien
F
Delaroche
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Olivier
O
Latry
2IRSEEM EA 4353,at the Graduate School of Engineering, ESIGELEC,76800 Saint-Etienne-du-Rouvray,France.
Blaise
B
Ravelo
1INSA Rouen,UNIROUEN,CNRS,GPM,Normandie Université,76000 Rouen,France.
Francois
F
Vurpillot
atom probe; field evaporation; mass resolution; pump-probe; short HV pulse