Blue and red electroluminescence of silicon-rich oxide light emitting capacitors

摘要

Electroluminescent properties of thin silicon-rich oxide (SRO) films deposited by low pressure chemical vapor deposition (LPCVD) were studied. The gas flow ratio Ro = N_2O/SiH_4 was changed to obtain different silicon concentrations within the SRO films. After deposition, SRO films were thermally annealed at 1100℃ for 3h in N_2 atmosphere in order to create silicon nanoparticles (Si-nps). Simple capacitive structures like Polysilicon/SRO-Si were used for the study. These light emitting capacitors (LECs) show intense blue (～466) and red EL (～685) at room temperature depending on the silicon excess within the SRO films. Electroluminescence in these LECs is obtained at direct current (DC) at both forward and reverse bias conditions. Nevertheless, a stronger whole area EL is obtained when devices are forwardly biased.