Plasma Profiling Time-of-Flight Mass Spectrometry for Fast Elemental Analysis of Semiconductor Structures with Depth Resolution in the Nanometer Range

• Published in: arXiv.org 2019-12
• Main Authors: Spende, Hendrik, Margenfeld, Christoph, Meyer, Tobias, Irene Manglano Clavero, Bremers, Heiko, Hangleiter, Andreas, Seibt, Michael, Waag, Andreas, Bakin, Andrey
• Format: Article
• Language: English
• Subjects: Cathodoluminescence; Composition; Depth profiling; Energy transmission; Field effect transistors; Gallium nitrides; Ions; Mass spectrometry; Quantum wells; Scanning transmission electron microscopy; Scientific imaging; Semiconductor devices; Spectroscopy
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1909.12779

Plasma profiling time of flight mass spectrometry (PP-TOFMS) has recently gained interest, as it enables the elemental profiling of semiconductor structures with high depth resolution in short acquisition times. As recently shown by Tempez et al., PP-TOFMS can be used to obtain the composition in the structures for modern field effect transistors [1]. There, the results were compared to conventional SIMS measurements. In the present study, we compare PP-TOFMS measurements of an Al-/In-/GaN quantum well multi stack to established micro- and nano-analysis techniques like cathodoluminescence (CL), scanning transmission electron microscopy (STEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). We show that PP-TOFMS is able to resolve the layer structure of the sample even more than 500 nm deep into the sample and allows the determination of a relative elemental composition with an accuracy of about 10 rel. %. Therefore, it is an extremely rapid alternative method to obtain semiconductor elemental depth profiles without expensive and time consuming sample preparation as it is needed for TEM. Besides, PP-TOFMS offers better depth resolution and more elemental information than for example electrochemical capacitance-voltage (ECV), as the acquisition of all elements occurs in parallel and not only electrically (ECV) or optically (CL) active elements are observed.