Raman spectroscopy of electrochemically self-assembled CdS quantum dots

We report a Raman spectroscopy investigation of electrochemically self-assembled quasiperiodic arrays of CdS quantum dots with characteristic feature size of 10 nm. The dots were synthesized using electrochemical deposition of CdS into a porous anodized alumina film. Polarization-dependent Raman scattering study over an extended frequency range reveals the quantization of electronic states in the conduction band and intersubband transitions. Raman peaks observed at 2919 and 3050 cm−1 are attributed to transitions between the lowest two subbands. The results suggest that quantum dot arrays, produced by inexpensive robust electrochemical means, may be suitable for infrared detector applications.