| 학회 | 한국재료학회 |
| 학술대회 | 2020년 가을 (11/18 ~ 11/20, 휘닉스 제주 섭지코지) |
| 권호 | 26권 1호 |
| 발표분야 | F. 광기능/디스플레이 재료 분과 |
| 제목 | Selective remote epitaxy of ZnO microrods using patterned graphene layer |
| 초록 | Two-dimensional materials (2DMs) are powerful tools for fabricating transferable and flexible heteroepitaxial semiconductor devices because the use of 2DM allows to exfoliate and transfer overlayer device from host substrate [1]. Remote epitaxy, as new epitaxy technique developed for overlayer exfoliation [2,3], allows to dictate the crystallographic registration of the underlying wafer to overlayer through the graphene layer. In the remote epitaxy, the field strength from the substrate penetrates ultrathin graphene to induce nucleation. Thus, the growth selectivity is determined by the thickness of graphene (remote epitaxial gap) lying on the substrate [3]. In this regard, we developed the patterned graphene layer for selective remote epitaxy of ZnO microrods (MRs). The patterned ultrathin graphene layer yielded MRs, whereas thick graphene area did not allow the growth of ZnO. Scanning electron microscopy was used to observe the surface morphology of ZnO microrod arrays, and Raman spectroscopy was utilized to confirm the presence and/or thickness of graphene before/after the growth of ZnO MRs. High-resolution scanning transmission electron microscopy (HR-STEM) corroborated that remote heteroepitaxial relation between ZnO and GaN across graphene. According to density-functional theory calculations, the thin patterned SLG area is advantageous to get through the electric field given from underlying GaN for remote epitaxy, rather than thick MLG mask area. The weak van der Waals adhesion of ZnO/patterned graphene/GaN was applied to delaminate the ZnO MRs overlayer by a thermal release tape-assisted exfoliation technique. Reference [1] C. H. Lee et al., Adv. Mater., 23, 4614 (2011) [2] Y. Kim et al., Nature 544, 340 (2017) [3] J. Jeong et al., Nanoscale, 10, 22970 (2018) |
| 저자 | 정준석, 진대권, 홍영준 |
| 소속 | 세종대 |
| 키워드 | <P>Remote epitaxy; Selective growth; Microrod; Hydrothermal synthesis; Graphene; ZnO; GaN</P> |
