| 학회 |
한국재료학회 |
| 학술대회 |
2019년 봄 (05/15 ~ 05/17, 평창 알펜시아 리조트) |
| 권호 |
25권 1호 |
| 발표분야 |
G. 나노/박막 재료 분과 |
| 제목 |
Monolithic 2D Oxide/Semiconductor Superlattice for Efficient Light Emitters |
| 초록 |
Semiconducting transition metal dichalcogenides (TMDCs) have been attracted enormous attention because of exceptional optical properties such as large exciton binding energy and direct bandgap transition at the monolayer limit. Such remarkable properties make them promising for high-performance light-emitting devices such as LEDs, LASERs, and single-photon quantum emitters. However, highly efficient luminescence in the two-dimensional (2D) semiconductor heterostructures is inherently limited due to the indirect band-gap transition at the multilayer regime as well as low quantum yield of constituent monolayers. Here, we propose a new approach to fabricate a high-efficiency luminescent 2D superlattice by monolithic phase engineering and van der Waals stacking. To achieve that, first, the bilayer WSe2 was converted to the WOX/WSe2 heterolayer by the layer-by-layer oxidation. Then, by multiply stacking the monolithically-phase-engineered WOX/WSe2 building blocks, we successfully achieve the 2D oxide/selenide superlattice structure. Unlike the case of stacking monolayers only, the photoluminescence (PL) characteristic was not quenched in this stacked heterostructure. As the number of the stacked WOX/WSe2 structures increases, PL intensity increases several times more than the simple sum of the single WOX/WSe2. This is presumably because the WOX layer acts as a decoupling layer between two adjacent monolayers, allowing to preserve the direct bandgap nature of monolayers even in the staked heterostructure. Our work suggests a new approach to fabricate 2D-based quantum heterostructures for high-performance light emitters. |
| 저자 |
Yoonseok Kim1, Huije Ryu2, Kangwon Kim3, Seong Won Lee4, Hong-Gyu Park5, Hyeonsik Cheong6, Gwan-Hyoung Lee7, Chul-ho Lee8
|
| 소속 |
1KU-KIST Graduate School of Converging Science and Technology, 2Korea Univ., 3Seoul, 402841, 5Department of Materials Science and Engineering, 6Seoul National Univeristy, 7Seoul 08826, 8Korea |
| 키워드 |
Two-dimensional materials; Transition-Metal dichalcogenides; Photoluminescence; Emission
|
| E-Mail |
|
