The (temperature-dependent) Raman spectra of some traditional semiconductors

• The Raman spectra of 15 semiconductors (Si, Ge, SiC, GaN, GaP, GaAs, GaSb, InP, InAs, ZnO, ZnS, ZnSe, ZnTe, CdS, and TiO 2 ) were measured in the 83−823 K range. • The results suggest an apparent relationship between the linear (above RT) dω/dT and dγ/dT slopes and the optical bandgaps E gap ’s (and corresponding dE gap /dT slopes) of the various semiconductor samples. • The most likely origins of these relationships are discussed, and their potential in proposing the most suitable materials and/or operation conditions for device applications are briefly outlined. Semiconductor materials represent the core of many modern technological applications and they are expected to continue influencing the ever-growing field of data generation-transmission-processing. This can be reached by means of new materials and/or devices but, especially, by precisely recognizing (and controlling) some of their main properties. In this regard, Raman scattering spectroscopy can contribute with important structural-electronic information by probing the phonon behavior − even in well-known semiconductors − over a wide temperature range. Accordingly, this work presents a comprehensive investigation of the Raman spectra of 15 semiconductors (Si, Ge, SiC, GaN, GaP, GaAs, GaSb, InP, InAs, ZnO, ZnS, ZnSe, ZnTe, CdS, and TiO 2 ) comprising IV-IV, III-V and II-VI compounds and different crystal structures (diamond, zinc blende, wurtzite, and rutile). Based on these spectra, all phonon modes were identified and the most prominent ones were analyzed in terms of their peak position ( ω ) and line-width ( γ ), in the 83 − 823 K temperature range, as obtained from fitting the spectra with Voigt functions. This part of the work includes a detailed study of the temperature-dependent ω T and γ T data according to the 3- and 4-phonon model, as well as their (supposedly) linear behavior above room-temperature. In the former case it was possible (at least qualitatively) to separate the contributions due to the anharmonic phonon–phonon interactions from the thermal expansion effects. In the latter, the results suggest an apparent relationship between the linear d ω / d T and d γ / d T slopes and the optical bandgaps E gap ’s (and their corresponding linear d E gap / d T slopes) of the various semiconductor samples − regardless of the compound type or crystal structure. The most likely origins of these relationships are discussed, and their potential in proposing the most suitable materials and/or operation conditions for device applications (as temperature probes or tunable optical filters, for instance) are briefly outlined.