Observation of Quantum Size Dependent Blue Shift in the Luminescence of Recrystallized Si/SiNx Superlattices

Abstract

ABSTRACTLight emitting Si nanostructures were fabricated by recrystallizing Si/SiNx superlattices grown by plasma enhanced chemical vapor deposition. After recrystallisation by a laser annealing or by rapid thermal annealing the Raman spectra show clearly a confinement effect. A substantial photoluminescence around 470 to 550 nm and at 620 nm is observed after a hydrogen passivation step. The photoluminescence at 620 nm is assigned to carrier recombination via efficient surface states, whereas the blue emission at 470 to 550 nm shows a behaviour expected for quantum confinement effects.