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Realization of a silicon-based light source is of significant importance for the future development of optoelectronics and telecommunications. Here, nanolaminate Al2O3/Tm2O3 films are fabricated on silicon utilizing atomic layer deposition, and intense blue electroluminescence (EL) from Tm3+ ions is achieved in the metal-oxide-semiconductor structured luminescent devices based on them. Precise control of the nanolaminates enables the study on the influence of the Tm dopant layers and the distance between every Tm2O3 layer on the EL performance. The 456 nm blue EL from Tm3+ ions shows a maximum power density of 0.15 mW/cm2. The EL intensities and decay lifetime decrease with excessive Tm dopant cycles due to the reduction of optically active Tm3+ ions. Cross-relaxation among adjacent Tm2O3 dopant layers reduces the blue EL intensity and the decay lifetime, which strongly depends on the Al2O3 sublayer thickness, with a critical value of ~3 nm. The EL is attributed to the impact excitation of the Tm3+ ions by hot electrons in Al2O3 matrix via Poole–Frenkel mechanism.

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The energy transfer from Yb 3þ to Er 3þ ions under electrical excitation which enhances the Er-related 1531 nm electroluminescence is evidenced, within the nanolaminate Yb,Er co-doped Al 2 O 3 films fabricated by atomic layer deposition. The light-emitting devices based on these nanolaminates present an external quantum efficiency up to 24% and the power efficiency of 2.8Â10 À3 , %60% higher than the solely Er-doped Al 2 O 3 device. The decay dynamics also support, with the radiative lifetime of the Yb 3þ emission reduced while that of Er 3þ emission rises. The Er 3þ and Yb 3þ ions are impact-excited by hot electrons, which stem from Poole-Frenkel conduction mechanism in Al 2 O 3 matrix. This work certifies the potential of sensitizing Er 3þ ions by the adjacent Yb 3þ ions under electrical excitation, and applications of the rare earth-doped nanolaminates in silicon-based optoelectronics.