Silver nanocrystals with the average diameter down to 4 nm were synthesized in Al 2O 3 matrix on Si substrate by pulse laser deposition followed by annealing at 400 °C in N 2 ambient. A photoluminescence (PL) band centered at 2.27 eV was recorded. A model based on the PL spectrum induced by the radiative recombination of sp-band electrons with d-band holes in the silver nanocrystals is suggested. Metal-insulator-semiconductor structures with Silver nanocrystals embedded in Al 2O 3 gate dielectric were fabricated. Large hysteresis behaviour in terms of large memory window and good data retention were characterized by capacitance–voltage and capacitance–time measurements.