標題: | Abnormal PL spectrum in InGaN MQW surface emitting cavity |
作者: | Chu, J. T. Cheng, Y. -J. Kuo, H. C. Lu, T. C. Wang, S. C. 光電工程學系 Department of Photonics |
關鍵字: | InGaN;GaN;MQW;vertical cavity;photoluminescence |
公開日期: | 1-一月-2008 |
摘要: | We report the observation of an abnormal photoluminescent (PL) spectrum from a HeCd laser pumped InGaN multiple quantum well (MQW) vertical cavity. The device is fabricated using standard MOCVD deposition on a (0001)-oriented sapphire substrate. The layer structures are: 10nm nucleation layer, a 4um bulk GaN layer, InGaN MQWs, and a final 200nm GaN cap layer. The InGaN MQWs consist of 10 pairs of 5 nm GaN barrier and 3 run In0.1Ga0.9N well. The peak emission of the as-grown MQWs sample was similar to 420nm. A dielectric distributed Bragg reflectors (DBR) were then coated on the top layer, followed by a laser lift off from sapphire substrate, and subsequently another DBR coated on the bulk GaN bottom surface. The cavity has a quality factor of similar to 520 from 400-490nm. The device was pumped by a focused CW HeCd laser from the bulk GaN side. When the laser is focused onto the InGaN MQWs, a photoluminescent spectrum centered at the designed MOW wavelength was observed as expected. However, when the focused position was moved toward the bulk GaN region, an additional abnormal PL peak around 460nm was observed. This is far outside the designed MQW wavelength. |
URI: | http://dx.doi.org/10.1117/12.762869 http://hdl.handle.net/11536/146789 |
ISBN: | 978-0-8194-7083-6 |
ISSN: | 0277-786X |
DOI: | 10.1117/12.762869 |
期刊: | VERTICAL-CAVITY SURFACE-EMITTING LASERS XII |
Volume: | 6908 |
起始頁: | 0 |
結束頁: | 0 |
顯示於類別: | 會議論文 |