Low threshold voltage blue light emitting diodes based on thulium doped gallium oxides

Abstract

Thulium doped gallium oxides (Tm-Ga 2 O 3 ) films were deposited on Si substrates by the pulsed laser deposition method. Blue emissions (476 nm and 460 nm) can be observed by the naked eye from Tm-Ga 2 O 3 /Si light emitting diodes (LEDs). The threshold voltage of Tm-Ga 2 O 3 /Si LEDs is 6.3 V, which is lower than that of Tm-GaN/Si devices. By combining our previously reported green emission from Er-Ga 2 O 3 and red emission from Eu-Ga 2 O 3 , strong blue emission from Tm-Ga 2 O 3 can realize the full-color LEDs with the single host of Ga 2 O 3 . These results open a pathway for integrating Ga 2 O 3 based full-color LEDs with mainstream Si technology.

Characteristics of Light‐Emitting Diodes Based on Terbium‐Doped Ga2O3 Films

“…With the exception of the Si substrate peaks appearing at around 28.5°and 58.9°, two distinct peaks emerge at 30.1°and 44.2°, corresponding to the (À401) and (À601) planes of monoclinic β-Ga 2 O 3 , respectively. [19,20] To further elucidate the structural properties of the films, we conducted Raman spectroscopy measurements. Monoclinic β-Ga 2 O 3 generally exhibits 15 Raman-active modes (10Ag þ 5Bg) predicted by density functional theory.…”

Color-Tunable Light-Emitting Diodes Based on Rare Earth Doped Gallium Oxide Films

“…(b) EL spectra of the LED under different injection currents. Reproduced with permission from ref . Copyright 2021 The Japan Society of Applied Physics.…”

“…Additionally, it has been observed that the temperature quenching effects exhibit an inverse relationship with the bandgap value of the host material. , Gallium oxide (Ga 2 O 3 ), which exhibits a significantly larger bandgap (4.9 eV) compared to GaN, is expected to be an excellent host material. In this spotlight article, we review the progress made toward achieving color-tunable LEDs based on RE doped Ga 2 O 3 semiconductors. − We have systematically studied the structural and optical characteristics of rare earth (Eu, Er, and Tm) doped Ga 2 O 3 films grown by pulsed laser deposition (PLD) and have demonstrated red, green, and blue LEDs based on these Eu, Er, and Tm doped Ga 2 O 3 films and achieved color-tunable LEDs using Eu, Er, and Tm codoped Ga 2 O 3 films.…”

Current-controlled electroluminescence from light-emitting diodes based on Tm, Er, and Eu codoped Ga2O3 thin films

“…Previously, we have observed pure blue, green, and red EL from LEDs based on Tm 3+ , Er 3+ , and Eu 3+ singly doped Ga 2 O 3 thin films, respectively. [26][27][28] In this work, bright and uniform pink light is emitted from the Ga 2 O 3 :(Tm+Er+Eu)-based LED, which is supposed to be a consequence of the color mixing of blue, green and red lights induced by the codoped Tm 3+ , Er 3+ , and Eu 3+ ions in the film.…”

“…Thereinto, the emissions located at 460 and 476 nm originate from the electronic transitions of 1 D 2 → 3 F 4 and 1 G 4 → 3 H 6 in Tm 3+ ions, respectively. 26) Two distinct emissions located at around 529 and 550 nm are caused by the transitions of 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 in Er 3+ ions, respectively. 27) Furthermore, another four remarkable emissions at about 595, 615, 657, and 712 nm correspond to Eu 3+ -associated emissions, induced by the transitions of 5 D 0 → 7 F 1 , 5 D 0 → 7 F 2 , 5 D 0 → 7 F 3 , and 5 D 0 → 7 F 4 , respectively.…”