Abstract
We report that the oxidation of graphene-based highly transparent conductive layers to AlGaN/GaN/AlGaN ultra-violet (UV) light-emitting diodes (LEDs) was suppressed by the use of SiNX passivation layers. Although graphene is considered to be an ideal candidate as the transparent conductive layer to UV-LEDs, oxidation of these layers at high operating temperatures has been an issue. The oxidation is initiated at the un-saturated carbon atoms at the edges of the graphene and reduces the UV light intensity and degrades the current-voltage (I-V) characteristics. The oxidation also can occur at defects, including vacancies. However, GaN-based UV-LEDs deposited with SiNX by plasma-enhanced chemical vapor deposition showed minimal degradation of light output intensity and I-V characteristics because the graphene-based UV transparent conductive layers were shielded from the oxygen molecules. This is a simple and effective approach for maintaining the advantages of graphene conducting layers as electrodes on UV-LEDs.
| Original language | English |
|---|---|
| Article number | 031108 |
| Journal | Applied Physics Letters |
| Volume | 101 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2012 Jul 16 |
Bibliographical note
Funding Information:The research at Korea University was supported by Basic Science Research Program (2011-0004270) through the National Research Foundation of Korea and the Center for Inorganic Photovoltaic Materials (No. 2012-0001171) grant funded by the Korea government (MEST), Korea University Grant and LG Innotek-Korea University Nano-Photonics Program. The research at the US Naval Research Lab was partially supported by the Office of Naval Research. The work at UF was partially supported by DTRA and NSF.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)