Existence of phase explosion during laser ablation and its effects on inductively coupled plasma-mass spectroscopy

Publication Type

Journal Article

Date Published

05/2001

LBNL Report Number

LBNL-47659

Abstract

A sudden increase in crater depth was observed during high irradiance (>1010 W/cm2) laser ablation of silicon, and it is attributed to the phenomenon of phase explosion. The threshold irradiance for phase explosion showed a dependence on two laser parameters:  laser beam spot size and wavelength. For a larger beam size and longer incident wavelength, a higher laser irradiance was required to generate phase explosion. The rapid increase of crater depth above the phase explosion threshold irradiance correlated with a significant increase in the ICPMS signal intensity. The ratio of crater volume to ICPMS intensity, which represents entrainment efficiency, remained the lowest at laser irradiances slightly above the phase explosion threshold. However, this ratio increased at irradiances well above the threshold (>1011 W/cm2). Chemical analysis using laser ablation at irradiance above 1011 W/cm2 provides increased sensitivity via improved entrainment and transport efficiency and increased ablation rate.

Journal

Analytical Chemistry

Volume

73

Year of Publication

2001

Short Title

Anal. Chem.

Pagination

2288-2293
2288

Issue

10

Accession Number

128