Abstract
Transparent conductive electrodes are critical to the operation of optoelectronic devices, such as photovoltaic cells and light emitting diodes. Effective electrodes need to combine excellent electrical and optical properties. Metal oxides, such as indium tin oxide, are commonly used. There is substantial interest in replacing them, however, motivated by practical problems and recent discoveries regarding the optics of nano-patterned metals. When designing nano-patterned metallic films for use as electrodes, one needs to account for both optical and electrical properties. In general, it is insufficient to optimize nano-structured films based upon optical properties alone, since structural variations will also affect the electrical properties. In this work, we investigate the need for simultaneous optical and electrical performance by analyzing the optical properties of a class of nano-patterned metallic electrodes that is obtained by a constant-sheet-resistance transformation. Within such a class the electrical and optical properties can be separated, i.e., the sheet resistance can be kept constant and the transmittance can be optimized independently. For simple one-dimensional periodic patterns with constant sheet-resistance, we find a transmission maximum (polarization-averaged) when the metal sections are narrow (< 40 nm, ~ 10% metal fill-factor) and tall (> 100 nm). Our design carries over to more complex two-dimensional (2D) patterns. This is significant as there are no previous reports regarding numerical studies on the optical and electrical properties of 2D nano-patterns in the context of electrode design.
| Original language | English (US) |
|---|---|
| Title of host publication | Plasmonics: Metallic Nanostructures and Their Optical Properties VIII |
| Publisher | SPIE-Intl Soc Optical Eng |
| ISBN (Print) | 9780819482532 |
| DOIs | |
| State | Published - Sep 10 2010 |
| Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): KUSC1-015-21
Acknowledgements: The authors thank J.-Y. Lee and P. Peumans for bringing this problem to their attention. This work was supported by the Center for Advanced Molecular Photovoltaics (CAMP) under Award No KUSC1-015-21 made by the King Abdullah University of Science and Technology, and by DOE Grant No. DE-FG02-07ER46426. The computation is performed through the support of NSF-LRAC program.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
