Aberration-corrected focused ion beam for time-of-flight secondary neutral mass spectrometry

A chromatic and spherical aberration corrector with liquid Ga ion metal source was developed. The aberration corrector reduced the ion probe diameter to similar to 1.5 times smaller for the Ga-69(+) beam in aberration correction mode compared with the corrector in non-aberration correction mode. The probe current at a given probe size is approximately two times larger in aberration correction mode than in non-aberration correction mode. The aberration-corrected focused ion beam yields higher lateral resolutions and higher sensitivities with lower acceleration voltage for the same acquisition time down to 10 nm with a current of 1 pA. (C) 2019 The Japan Society of Applied Physics