Upadhyay, S.; Subrahmanyam, N. B. V.; Gupta, S. K.; Bhagwat, P.; and others (IADD)
Source
Proceedings of SPIE - The International Society for Optical Engineering, 2016. Vol. 9933: Article no. 993305
ABSTRACT
We have investigated the effect of implantation of Lithium ions of varying energies from 20 keV to 50 keV at fixed dose 2 × 1012 ions/cm2 on InAs/GaAs QDs. Temperature dependent (15K-300K) photoluminescence (PL) study was carried for all samples. Implantation resulted consistent degradation in PL efficiency with rise in energy of ions. The same trend was also observed while varying the fluence at fixed energy. Suppression in PL intensity might be due to creation of defects/damage profile in the vicinity of the QDs which act as trapping centers for photocarriers. Implantation also resulted in decrease of activation energies from 230 meV (as-grown) to 35 meV (50 keV) indicating reduced carriers confinement in QDs. The 50 keV sample demonstrated the mild red shift in PL spectra which is probably originated from atomic interdiffussion between dots and barrier layer caused by local heat generation.