A Study of Imprint Structure Applied to GaN Light-Emitting Diode
| Autor: | Shang-Yen Wu, 吳尚彥 |
|---|---|
| Rok vydání: | 2008 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 96 In this study, micro-structures were fabricated on wire bonding LED. Light extraction efficiency enhancement and far field pattern modulation can be achieved by such micro-structures. Different to traditional surface roughness and chip shaping, we use embossing technique to make micro-structures. Embossing technique possesses large area, high yield, and low fabrication cost. Most important of all the method will not damage the electrical performance of LED. The index of imprinting material, SOG, is 1.4 which is smaller than transparent conduction layer and air, so that the transmission decay due to index difference can be reduced. Besides, the property of SOG is similar to SiO2 such property can be used as a package material. The forward voltage of our LED after embossing processing can be maintained at 3.4V at 20mA. However, the light extraction efficiency performances dependent different 2D cylinder, pyramid and 1D grating which can raise 39.1%, 35.3% and 19.8%. The far field pattern is also changed from Lambertian light source to an asymmetric one. In the future, we will use such performance to work with the other optical design and increase the application of LED. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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