首先采用多靶射频磁控共溅射结合后退火工艺制备了掺Er富硅氧化硅MIS(金属-绝缘体-半导体结构)电致发光器件,然后通过电致发光(EL)以及电流-电压(I-U)特性测量对发光器件的光电性能进行表征.最后,通过对比不同富硅含量的发光器件的载流子输运机制,并通过分析器件中的电荷俘获过程,对富硅氧化硅器件中铒离子电致发光的激发和猝灭机制进行了解释.结果表明:富硅的存在改变了MIS发光器件中的载流子输运过程,造成外加电场下注入的电子能量降低,进而降低Er离子发光中心的激发效率;而富硅引入的缺陷态会引起电荷俘获及俄歇效应,也会使得发光中心发生非辐射复合过程.
The metal insulator semicsnductor light emitting diod(MIS-LED)with the erbium-doped silicom-rich silicom oxide was fabricated by radio frequency co-sputtering combined with post-annealing technique.The luminescence and electrical properties of the device were characterized by electroluminescence(EL)spectra and current-voltage measurement.Carrier transport and charge trapping mechanisms of the LEDs with different excess silicon content were investigated.Excitation and quenching mechanisms of the electroluminescence from erbium ions in the device were also studied and explained.The results indicated that, with the excess silicon in the MIS-LEDs, the conduction of carriers transform from Fowler-Nordheim tunneling to hopping conduction and the quenching of the EL can be attributed to the energy reduction of the injected electrons and the lowered excitation efficiency of the erbium ions.In addition, the Auger effect induced by charge trapping would also account for the nonradiative recombination processes.
[1] 沈浩, 李东升, 杨德仁.硅基光源的研究进展[J].物理学报,2015,64:204-208.
[2] KENYON A J, TRWOGA P F, FEDERIGHI M, et al.Optical properties of PECVD erbium-doped silicon-rich silica: evidence for energy transfer between silicon microclusters and erbium ions [J].J Phys: Condens Matter, 1994, 6(21): L319-324.DOI:1088,0953-8984/6/21/007.
[3] IACONA F, PACIFICI D, IRRERA A,et al.Electroluminescence at 1.54μm in Er-doped Si nanocluster-based devices [J].Appl Phys Lett, 2002,81(17): 3242-3244.
[4] IRRERA A, IACONA F, FRANZO G, et al.Influence of the matrix properties on the performances of Er-doped Si nanoclusters light emitting devices [J].J Appl Phys, 2010, 107: 054-302.
[5] NAZAROV A, SUN J M, SKORUPA W, et al.Light emission and charge trapping in Er-doped silicon dioxide films containing silicon nanocrystals [J].Appl Phys Lett, 2005,6(15): 151-914.
[6] NAZAROV A, Gebel T, REBOHLE L, et al.Trapping of negative and positive charges in Ge+ ion implanted silicon dioxide layers subjected to high-field electron injection [J].J Appl Phys, 2003, 94(7): 40-44.
[7] SAVIO R L, GALLI M, LISCIDINI M, et al.Photonic crystal light emitting diode based on Er and Si nanoclusters co-doped slot waveguide[J].Apllied Physics Letters, 2014, 104(104): 121107.
[8] LÜ C, ZHU C, WANG C, et al.Electroluminescence from metal-oxide-semiconductor devices with erbium-doped CeO2 films on silicon[J].Applied Physics Letters, 2015, 106(14): 141102.
[9] NAZAROV A, SUN J M, SKORUPA W, et al.Light emission and charge trapping in Er-doped silicon dioxide films containing silicon nanocrystals [J].Appl Phys Lett, 2005,86(15): 151914.
[10] NAZAROV A, GEBEL T, REBOHLE L, et al.Trapping of negative and positive charges in Ge+ ion implanted silicon dioxide layers subjected to high-field electron injection [J].J Appl Phys, 2003, 94(7): 4440.
[11] NAZAROV A, TIAGULSKYI S, TYAGULSKYY I, et al.The effect of rare-earth clustering on charge trapping and electroluminescence in rare-earth implanted metal-oxide-semiconductor light-emitting devices[J]. J Appl Phys, 2010, 107(12): 123112.
[12] PRIOLO F, PRESTI C D, FRANZò G, et.al.Carrier-induced quenching processes on the erbium luminescence in silicon nanocluster devices [J]. Physical Review B, 2006, 73(11): 113302.
