Efficient light emission from Si pn diodes and metal-oxide-semiconductor structures

Light emission from silicon has attracted considerable attention in the past few years due to the future potential in on-chip and inter-chip optical interconnects. This report reviews our current research work on efficient electroluminescence (EL) from silicon pn diodes and metal oxide semiconductor (MOS) devices. Efficient band edge EL with attractive power efficiencies up to 0.12 % has been observed in Si pn diodes prepared by boron implantation. We focus on the origin of the relatively high EL efficiency in Si pn diodes prepared by high-dose boron implantation, especially on the intriguing and anomalous increase of the EL for a temperature increase up to room temperature. EL from rare earth doped metal oxide semiconductor (MOS) devices was also studied using ion implantation of different rare earth luminescent centers (Gd3+, Tb3+, Eu3+, Ce3+, Tm3+, Er3+) into the silicon dioxide layers with a transparent top electrode made of indium-tin oxide. Strong EL was obtained from different rare earth centers in UV to infrared. The electroluminescence properties were studied with respect to the luminescence spectra, decay time, impact excitation, cross relaxation (Tb3+), and efficiency. Top external quantum efficiency above 15 % was obtained, which is comparable to the InGaN quantum well light emitting diodes