Quantitative comparison between Auger electron spectroscopy and secondary ion mass spectroscopy depth profiles of a double layer structure of AlAs inGaAs using the mixing-roughness-information depth model

Application of the so called mixing-roughness-information (MRI) depth model to quantitative reconstruction of the in-depth distribution of the composi tion is demonstrated by comparing secondary ion mass spectroscopy (SIMS) an d Auger electron spectroscopy (AES) depth profiles. A GaAs/AlAs reference s ample consisting of two layers of AlAs [1 and 36 monolayer (ML)] separated by 44 ML of a GaAs matrix was depth profiled using almost identical sputter ing conditions: Ar+ ions of 3 keV impact energy and 52 degrees (SIMS: CAMEC A 4f) and 58 degrees (AES: VG Microlab 310F) incidence angle. Both the Alintensity of the SIMS profile and the Al (LM intensity of the AES profile w ere quantified by fitting the measured profiles with those calculated with the MRI model, resulting in the same mixing length of 3.0 +/- 0.3 nm, simil ar roughness parameter (1.4-2 nm), and negligible information depth (0.4 nm ), Whereas practically no matrix effect was observed for AES as well as for Al+ in the SIMS profile, quantification using dimer (Al+) and trimer (Al+) ions shows a marked nonlinearity between concentration and intensity, with the main effect caused by the simple mass action law probability of cluste r ion formation. (C) 2001 American Vacuum Society.