Quantitative and Sensitive Profiling of Dopants and Impurities in SemiconductorsUsing Sputter-Initiated Resonance Ionization Spectroscopy

摘要

Sputter-initiated resonance ionization spectroscopy (SIRIS) is an analyticaltechnique with extremely high sensitivity, selectivity, dynamic range, and quantitation accuracy. SIRIS also provides good spatial resolution, and freedom from matrix effects on surfaces and at interfaces. In this paper we report the capability of SIRIS to quantitate, with high accuracy and high depth resolution, dopant and impurity concentrations in semiconductor devices at the 10(exp 13 approx. 10(exp 20) atoms/cu cm level. By utilizing layered GaAs/AlGaAs/GaAs samples grown by molecular beam ) epitaxy, a depth resolution of approx. 2 nm has been demonstrated using 0.5 keV Ar+ primary ion energy. Depth profiles of boron in Si implants showed dynamic ranges up to 2 x 10(exp 6). The correlation between B concentration and B SIRIS signal demonstrated high quantitation accuracy. The lateral imaging capability of SIRIS was demonstrated. We concluded that an optimized instrument could produce high depth-resolved quantitative measurements