Characterization in Silicon Processing

Inductively Coupled

Plasma Mass Spectrometry

(ICPMS)*

11

Inductively coupled plasma mass spectrometry (ICPMS) uses an inductively cou-

pled plasma to generate ions

that

are subsequently analyzed by a mass spectrometer.

The plasma is a highly efficient ion source

that

gives detection limits below 1 ppb

for

most

elements. The technique allows

both

fiilly

quantitative and semiquantita-

tive

analyses. Samples usually are introduced as liquids but recent developments

allow

the direct sampling of solids by laser ablation-ICPMS, and gases and vapors

using a special

torch

design. Solids or thin films are, however, more usually digested

into solution