Low-band gap nanoparticles embedded in high-K dielectrics

In this paper our recent research on Ge and PbS nanoparticles embedded in ZrO₂ will be reviewed. Ge nanoparticles have been deposited by rf-cosputtering of ZrGe₂O_2.9/ZrO₂ superlattices and subsequent annealing. ZrO₂ and the phase separated Ge crystallizes at 650°C into nanocrystalline layers. These layers show a luminescence signal at 2.5 eV, which is contributed to defect luminescence. PbS nanoparticles have been fabricated using wet chemical methods and embedded in the ZrO₂ matrix by sol-gel deposition. In this case a luminescence signal at 1.3 μm has been detected after annealing at 100°C.