Improvement of Mass Resolution in Wide-Angle Laser-Assisted Atom Probe by Flight Path Compensation

Abstract

A wide-angle laser-assisted three-dimensional atom probe (3DAP) was developed, with a wide angle (0.75 sr) and short flight distance (110 mm) adopted to enlarge the analysis area of the tip. However, the short flight distance of ions resulted in the degradation of mass resolution. Therefore, flight path compensation was examined to improve the mass resolution in the 3DAP with a flight distance of 110 mm. With geometric compensation based on a simple concentric sphere model, the detected ions could be identified. By the compensation of the flight path for a small inclination on the microchannel plate (MCP) in the direction normal to the tip axis, the isotopes of detected ions were identified and high mass resolution was attained for a very short flight distance. [DOI: 10.1380/ejssnt.2009.35]