Study of carrier concentration profiles in Al-implanted Ge by micro-Raman spectroscopy under different excitation wavelengths

• Published in: Journal of Raman spectroscopy 2013-05, Vol.44 (5), p.665-669
• Main Authors: Sanson, A., Giarola, M., Napolitani, E., Impellizzeri, G., Privitera, V., Carnera, A., Mariotto, G.
• Format: Article
• Language: English
• Subjects: Aluminum; carrier concentration; Carrier density; Estimates; Excitation; Ge doping; Germanium; Lasers; micro-Raman spectroscopy; Spectroscopy; spreading resistance profiling; substitutional atoms; Wavelengths
• ISSN: 0377-0486; 1097-4555
• DOI: 10.1002/jrs.4249

The distribution profile of Al implanted in crystalline Ge has been investigated by micro‐Raman spectroscopy. Using different excitation laser lines, corresponding to different optical penetration depths, the Al concentration at different depths beneath the sample surface has been studied. We have found a strong correlation between the intensity of the Al–Ge Raman peak at ~370 cm−1, which is due to the local vibrational mode of substitutional Al atoms, and the carrier concentration profile, obtained by the spreading resistance profiling analysis. A similar connection has been also observed for both shape and position of the Ge–Ge Raman peak at ~300 cm−1. According to these experimental findings, we propose here a fast and nondestructive method, based on micro‐Raman spectroscopy under different excitation wavelengths, to estimate the carrier concentration profiles in Al‐implanted Ge. Copyright © 2013 John Wiley & Sons, Ltd. The distribution profile of Al implanted in crystalline Ge has been investigated by micro‐Raman spectroscopy under different excitation laser lines, corresponding to different optical penetration depths. A fast and non‐destructive method, based on micro‐Raman spectroscopy, is proposed to estimate the carrier profiles in Ge.