Ultra-low reflection porous silicon nanowires for solar cell applications
Type
ArticleKAUST Department
Advanced Nanofabrication, Imaging and Characterization Core LabComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Core Labs
Imaging and Characterization Core Lab
Physical Science and Engineering (PSE) Division
Date
2012-07-11Online Publication Date
2012-07-11Print Publication Date
2012-07-16Permanent link to this record
http://hdl.handle.net/10754/562009
Metadata
Show full item recordAbstract
High density vertically aligned Porous Silicon NanoWires (PSiNWs) were fabricated on silicon substrate using metal assisted chemical etching process. A linear dependency of nanowire length to the etching time was obtained and the change in the growth rate of PSiNWs by increasing etching durations was shown. A typical 2D bright-field TEM image used for volume reconstruction of the sample shows the pores size varying from 10 to 50 nm. Furthermore, reflectivity measurements show that the 35% reflectivity of the starting silicon wafer drops to 0.1% recorded for more than 10 μm long PSiNWs. Models based on cone shape of nanowires located in a circular and rectangular bases were used to calculate the reflectance employing the Transfert Matrix Formalism (TMF) of the PSiNWs layer. Using TMF, the Bruggeman model was used to calculate the refractive index of PSiNWs layer. The calculated reflectance using circular cone shape fits better the measured reflectance for PSiNWs. The remarkable decrease in optical reflectivity indicates that PSiNWs is a good antireflective layer and have a great potential to be utilized in radial or coaxial p-n heterojunction solar cells that could provide orthogonal photon absorption and enhanced carrier collection. ©2012 Optical Society of America.Citation
Najar, A., Charrier, J., Pirasteh, P., & Sougrat, R. (2012). Ultra-low reflection porous silicon nanowires for solar cell applications. Optics Express, 20(15), 16861. doi:10.1364/oe.20.016861Publisher
The Optical SocietyJournal
Optics Expressae974a485f413a2113503eed53cd6c53
10.1364/OE.20.016861