Erbium-implanted tellurite waveguides with low-temperature post-implantation activation and signal enhancement
In this paper, we demonstrate erbium ion implantation and signal enhancement in tellurium oxide hybrid waveguides. Silicon nitride strips with a width of 2 $μ$m and a height of 100 nm were clad with a 110-nm-thick tellurium oxide layer to form hybrid waveguides, followed by erbium ion implantation at an energy of 200 keV and a dose of $1\times10^{15} ions/cm^{2}$, with a projected peak implantation depth of approximately 50 nm into the tellurium oxide layer. After low-temperature annealing at 150 °C for 30 minutes, the propagation loss decreased from 1.7 to 0.9 dB/cm, while the erbium lifetime increased from 40 $μ$m to over 800 $μ$m. We measure a small-signal enhancement of 9 dB in an 11-cm-long waveguide at a wavelength of 1550 nm. These results demonstrate progress towards a low-temperature post-ion implantation process for incorporating erbium and other rare earth ions into tellurium oxide films for integrated photonic applications.