| Autor: |
A. Kadys, Shanti Bhattacharya, Gediminas Seniutinas, Anand Vijayakumar, Saulius Juodkazis, R. Tomašiūnas, Edgaras Jelmakas, Gediminas Gervinskas |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| Popis: |
GaN light emitting diodes (LEDs) on sapphire substrates can be improved by micro-patterning substrate to perform epitaxial over-growth which drastically reduces defects' density in the light emitting region. We patterned Al 2 O 3 with focused ion beam and show a successful overgrowth of GaN. The exact shape of pattern milled into Al 2 O 3 was replicated into a 0.4-mm-thick shim of Ni by electroplating. The surface roughness of Ni was ~5:5 ±2 nm and is applicable for the most demanding replication of nano-rough surfaces. This technique can be used to replicate at micro-optical elements Fresnel-axicons defined by electron beam lithography made on sub-1 mm areas without stitching errors (Raith EBL). Shimming of macro-optical elements such as car back- reflectors is also demonstrated. Ni-shimming opens possibility to make replicas of nano-textured small and large area patterns and use them for thermal embossing and molding of optically-functionalized micro-fluidic chips and macro-optical elements. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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