Imaging of a patterned and buried molecular layer by coherent acoustic phonon spectroscopy

MIKE HETTICH; KARL JACOB; OLIVER RISTOW; CHUAN HE; JAN MAYER; MARTIN SCHUBERT; VITALYI GUSEV; AXEL BRUCHHAUSEN; THOMAS DEKORSY

APPLIED PHYSICS LETTERS

AMER INST PHYSICS

Lugar: American Institute of Physics; Año: 2012 vol. 101 p. 191606 - 191606

0003-6951

A molecular layer of aminopropyltriethoxysilane is patterned with a focused ion beam and subsequently covered by a gold film. The gold-polymer-substrate structures are afterwards imaged by ultrafast coherent acoustic phonon spectroscopy in reflection geometry. We demonstrate that the lateral structure of the covered polymer layer can be detected via the damping time of the vibrational mode of the gold film. Furthermore, we utilize Brillouin oscillations originating from the silicon substrate to map the structures and to estimate the molecular layer thickness.