| 학회 |
한국재료학회 |
| 학술대회 |
2019년 봄 (05/15 ~ 05/17, 평창 알펜시아 리조트) |
| 권호 |
25권 1호 |
| 발표분야 |
G. 나노/박막 재료 분과 |
| 제목 |
Effect of UV-O3 functionalization on the optoelectronic properties of WS2 and WSe2 single layers |
| 초록 |
Unlike graphene, the existence of direct bandgaps in transition metal dichalcogenides such as WS2 and WSe2 offers an attractive possibility of using single layer MoS2 in optoelectronic devices. Because of the absence of dangling bonds in WS2 and WSe2, surface treatment such as ultraviolet-ozone (UV-O3) treatment is necessary before the deposition of high-k dielectrics on MoS2 to fabricate optoelectronic devices such as phototransistors. However, little interest has been given to the effect of UV-O3 treatment on the optoelectronic properties of single layer WS2 and WSe2. In this presentation, we systematically investigate the effect of UV-O3 treatment on the photoluminescence of mechanically exfoliated single layer WS2 and WSe2 flakes. We observe photoluminescence quenching in single layer WS2 and WSe2 depending on UV-O3 treatment time and explore possible mechanisms. Also, we observe the reduction of the Raman intensity in single layer WS2 and WSe2 with increasing UV-O3 treatment time. Through X-ray photoelectron spectroscopy, we confirm new oxygen bondings on single layer WS2 and WSe2 surfaces. We further fabricate thin film transistors based on single layer WS2 and WSe2 and measure the change of the electrical characteristics by UV-O3 treatment. These results demonstrate the significant impact of UV-O3 treatment on the optoelectronic properties of single layer WS2 and WSe2 highlighting the importance of using optimized surface treatment process conditions. |
| 저자 |
Minji Kang1, Hae In Yang2, Woong Choi3
|
| 소속 |
1School of Materials Science & Engineering, 2Kookmin Univ., 3Seoul 02707 |
| 키워드 |
TMDC; ultraviolet-ozone; WS2; WSe2
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| E-Mail |
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