Premium
Detection limit for carbon in InSb during SIMS depth profiling
Author(s) -
Galuska A. A.,
Greulich F. G.
Publication year - 1991
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.740170106
Subject(s) - secondary ion mass spectrometry , detection limit , carbon fibers , analytical chemistry (journal) , ion , chemistry , materials science , chromatography , organic chemistry , composite number , composite material
Secondary ion mass spectrometry (SIMS) is commonly used to determine the depth distribution of carbon in semiconductors. Carbonaceous residual gases in SIMS insturumentation and memory effects associated with carbon redeposition within the sputtered craters normally limit the detectability of carbon to ∼ 1 × 10 17 C cm −3 . In this investigation, the effects of primary ion (Cs + and O 2 + ), primary ion current (also current density), secondary ion, secondary ion energy discrimination, cryogenic cold finger and vacuum on the SIMS analysis of carbon in InSb were examined and optimized. Under optimized analysis conditions, the detection limit for carbon was reduced to ∼ 1 × 10 16 C cm −3 . Detection of the 123 SB 12 C − molecular ion rather than 12 C − was found to increase the sensitivity to carbon by ∼ 3 ×. In addition, 123 Sb 12 C − was found to be less sensitive to carbon contamination present on as‐received surfaces or incorporated from the analytical environment.