| 학회 | 한국재료학회 |
| 학술대회 | 2017년 봄 (05/17 ~ 05/19, 목포 현대호텔) |
| 권호 | 23권 1호 |
| 발표분야 | 5. 나노공정과 메타물질(Nano-fabrication and meta-materials) |
| 제목 | 가시광-근적외선용 나노스케일 3차원 메타물질 제작과 활용 |
| 초록 | Metamaterials, artificially structured nanomaterials, have enabled unprecedented phenomena such as negative refraction. Here, we discuss recent development of hierarchical fabrication techniques for three-dimensional metamaterial and plasmonic structures based on ultra-accurate and precise electron-beam lithography overlay. Accordingly, we can realize any kind of three-dimensional nanostructures for optical metamaterials. Fabrication of only two-dimensional nanostructures on planar substrates has been possible so far because conventional nanofabrication methods were not feasible to realize three-dimensional nanostructures. Generally, they were very thin so that we called them “metasurfaces”. Although metasurfaces have shown many exotic physical phenomena and applications, they have critical issues of inhomogeneous and anisotropic optical characteristics such as narrow bandwidth in operation, incident angle dependence and polarization dependence inevitably. These issues are obstacles to be applied real devices. To overcome these obstacles and realize them into the device applications, three-dimensional nanofabrication process should be developed. To be a real material, one should have homogeneous bulk characteristics as well as independence of polarization and incident angle of the incident light. Only way to satisfy these conditions is to make three-dimensional metamaterials. Two ways are possible; one is using three-dimensional unit cell building blocks to make metamaterials, and the other is stacking functional layers repeatedly. Typical example of the latter method is electron-beam lithography overlay process which can generate nano-scale three-dimensional structures. We have demonstrated many kinds of three-dimensional optical metamaterials by using aforementioned overlay process. All of them are almost impossible to realize by using other nanofabrication techniques such as focused ion beam milling, nanoimprint lithography and direct laser writing method. Every overlay process, we could have achieved extremely small overlay error under 20 nm by using our self-developed virtual alignment marks. It means that electron-beam lithography overlay process can be the most promising and appropriate nanofabrication platform for three-dimensional optical metamaterials. |
| 저자 | 김민경, 윤관호, 김인기, 소순애, 문정호, 노준석 |
| 소속 | 포항공과대 |
| 키워드 | <P>메타물질; 나노공정; 나노포토닉스</P> |
