Charge trapping phenomena in high-efficiency metal-oxide-silicon light-emitting diodes with ion-implanted oxide

• Published in: Journal of luminescence Vol. 121; no. 2; pp. 213 - 216
• Main Authors: Nazarov, A., Osiyuk, I., Tyagulskii, I., Lysenko, V., Prucnal, S., Sun, J., Skorupa, W., Yankov, R.A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.12.2006; Elsevier
• Subjects: Applied sciences; Charge trapping; Electroluminescence; Electronics; Exact sciences and technology; Optoelectronic devices; Rare-earth implanted oxide; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Charge trapping; Electroluminescence; Rare-earth implanted oxide; Ion implantation; Doping; Electron injection; Germanium addition; Light emitting diode; Rare-earth metal addition; Charge carrier trapping; Silicon oxides; Luminescence quenching; Voltage capacity curve
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2006.07.014

This work is a comparative study of the processes of charge trapping in silicon dioxide layers doped with different rare-earth (RE) impurities (Gd, Tb, Er) as well as with Ge. Diode SiO 2–Si structures incorporating such oxide layers exhibit efficient electroluminescence (EL) in the spectral range of UV to IR. Ion implantation was performed over a wide dose range with the implant profiles peaking in the middle of the oxide. Charge trapping was studied using an electron injection technique in constant current regime with simultaneous measurements of the EL intensity (ELI). High-frequency C/ V characteristics were used to monitor the net charge in the oxides. Analysis of the charge trapping and the variation of the EL intensity during electron injection shows that the current density range can be divided in three portions: (i) low injection level, where electron/hole capture at traps with large capture cross-sections and low ELI occurs; (ii) medium injection level corresponding to the main operation mode of the devices (odd hole trapping depending on the injected current level is observed); and (iii) high injection level (electrical quenching of the EL that correlates with electron capture at traps of extremely small capture cross-sections takes place). The nature of specific hole trapping at the medium injection level in RE-doped devices is discussed. Mechanisms of EL quenching at the high injection level are proposed.