Comparison of secondary ion mass spectroscopy analysis of ultrashallow phosphorus using Cs super(+), O super(+) sub(2), and CsC super(-) sub(6) primary ion beams

Secondary ion mass spectroscopy (SIMS) analysis of ultrashallow phosphorus implanted into silicon, was compared using Cs super(+), O super(+) sub(2), and CsC sub(6) super(-) primary ion beams. Samples were analyzed with and without sample rotation to study the possible influence of beam induced crater bottom roughening on the instantaneous removal rate and hence depth calibration. Results indicated that the use of cesium containing negative cluster ions extracted from sputter negative ion sources, coupled with negative secondary ion extraction, provided a useful method for analyzing shallow n-dopant profiles in magnetic sector SIMS.