In the race to enhance the efficiency of solar cells, spending the time and effort to get tiny nanowires to line up neatly on the top of ordinary silicon wafers may not be worth the effort.
The nanowires, which are wrapped in a shell of silicon oxide, serve as an antireflective coating on top of the usually shiny silicon wafer.
The scraggly tangle captures light ranging in color from red to violet, and the random orientation of the wires means the coating would continue to absorb light even as the angle of the Sun changes throughout the day.
The researchers fabricated the jumbled, yet effective, antireflective coating by vaporizing silicon powder and then depositing it on top of a silicon wafer.
The process, described in the AIP’s new journal AIP Advances, is relatively inexpensive and could be scaled up for large manufacturing operations. For future work the team plans to create structures that are more ordered to test if the messy arrangement really is better.
The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by American Institute of Physics.
- P. Pignalosa, H. Lee, L. Qiao, M. Tseng, Y. Yi. Graded index and randomly oriented core-shell silicon nanowires for broadband and wide angle antireflection. AIP Advances, 2011; 1 (3): 032124 DOI:10.1063/1.3624838