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Two infrared (IR)-active vibrational modes, observed at 93 and 113 cm− 1 in Raman scattering, are evidence of an inversion symmetry breakdown in thin (∼ 10 nm) nanoplates of topological insulator Bi 2 Te 3 as-grown on SiO 2. Both Raman and IR modes are preserved after typical device fabrication processes. In nanoplates transferred to another SiO 2 substrate via contact printing, however, the IR modes are absent, and the Raman spectra are similar to those from bulk samples. The differences between as-grown and transferred nanoplates may result from nanoplate–substrate interactions.