Correlation between efficiency and stability in Er- and Si-implanted MOS light emitting devices

Er-based light emitters, which can be electrically driven and easily integrated into Si-based circuitries, are of great interest for a broad palette of applications, especially in the field of telecommunication and sensing. Among the different approaches Er-implanted MOS devices feature their excellent compatibility to standard CMOS processes and the reproducibility of the implantation process. However, at present such devices do achieve neither the efficiency nor the operation lifetime usually required for such applications.
In this study we compare various designs of Er-implanted MOS devices with respect to their electroluminescence efficiency and electrical operation lifetime. The different designs comprise devices implanted with Er alone or co-implanted with Si and Er, various single and multilayer systems and different host matrices for Er, namely SiO2 or Si-rich Si3N4. Despite the different design parameters, a strong correlation between efficiency and operation lifetime is found. This behavior is explained by the ambivalent role of hot electrons which play a key role both for the efficient excitation of erbium and for the oxide degradation.