Limits...
Fabrication and characterization of silicon wire solar cells having ZnO nanorod antireflection coating on Al-doped ZnO seed layer.

Baek SH, Noh BY, Park IK, Kim JH - Nanoscale Res Lett (2012)

Bottom Line: The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination.The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering.Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it.

View Article: PubMed Central - HTML - PubMed

Affiliation: Energy Research Division, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 50-1, Sang-Ri, Hyeonpung-Myeon, Dalseong-gun, Daegu, 711-873, South Korea. jaehyun@dgist.ac.kr.

ABSTRACT
In this study, we have fabricated and characterized the silicon [Si] wire solar cells with conformal ZnO nanorod antireflection coating [ARC] grown on a Al-doped ZnO [AZO] seed layer. Vertically aligned Si wire arrays were fabricated by electrochemical etching and, the p-n junction was prepared by spin-on dopant diffusion method. Hydrothermal growth of the ZnO nanorods was followed by AZO film deposition on high aspect ratio Si microwire arrays by atomic layer deposition [ALD]. The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination. The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering. Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it.

No MeSH data available.


SEM images of the SiMW arrays fabricated by electrochemical etching. (a) Top view and (b) cross section view.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3278341&req=5

Figure 1: SEM images of the SiMW arrays fabricated by electrochemical etching. (a) Top view and (b) cross section view.

Mentions: Figure 1 shows the SEM images of the SiMW arrays formed by electrochemical etching. The etching method used in this work to produce ordered arrays of the SiMW is based on the formation of porous silicon using anodic oxidation [24]. By etching a bulk Si substrate in HF electrolyte with electric field, Si can be etched to produce long, straight-walled, uniform pores having micrometer-sized dimensions. The pore formation in p-type Si is believed to occur through a hole-limited silicon dissolution process [24]. As the applied current density increased, the macropores are gradually grown and became interconnected. Finally, a well-ordered array of vertical SiMWs with diamond shape appeared at the corners between the four nearest pores (Figure 1a). Full fabrication process of ordered macropores in p-type Si using HF-based solution is definitely described elsewhere [25,26]. The pore diameter and spacing can be controlled by the current density of the etching, the applied voltage, and the doping of the sample, while the pore length can be controlled independently by adjusting the etching time. The cross section SEM image reveals that the size of the SiMW is 1.5 μm in diameter and 16 μm in length as shown in Figure 1b.


Fabrication and characterization of silicon wire solar cells having ZnO nanorod antireflection coating on Al-doped ZnO seed layer.

Baek SH, Noh BY, Park IK, Kim JH - Nanoscale Res Lett (2012)

SEM images of the SiMW arrays fabricated by electrochemical etching. (a) Top view and (b) cross section view.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3278341&req=5

Figure 1: SEM images of the SiMW arrays fabricated by electrochemical etching. (a) Top view and (b) cross section view.
Mentions: Figure 1 shows the SEM images of the SiMW arrays formed by electrochemical etching. The etching method used in this work to produce ordered arrays of the SiMW is based on the formation of porous silicon using anodic oxidation [24]. By etching a bulk Si substrate in HF electrolyte with electric field, Si can be etched to produce long, straight-walled, uniform pores having micrometer-sized dimensions. The pore formation in p-type Si is believed to occur through a hole-limited silicon dissolution process [24]. As the applied current density increased, the macropores are gradually grown and became interconnected. Finally, a well-ordered array of vertical SiMWs with diamond shape appeared at the corners between the four nearest pores (Figure 1a). Full fabrication process of ordered macropores in p-type Si using HF-based solution is definitely described elsewhere [25,26]. The pore diameter and spacing can be controlled by the current density of the etching, the applied voltage, and the doping of the sample, while the pore length can be controlled independently by adjusting the etching time. The cross section SEM image reveals that the size of the SiMW is 1.5 μm in diameter and 16 μm in length as shown in Figure 1b.

Bottom Line: The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination.The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering.Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it.

View Article: PubMed Central - HTML - PubMed

Affiliation: Energy Research Division, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 50-1, Sang-Ri, Hyeonpung-Myeon, Dalseong-gun, Daegu, 711-873, South Korea. jaehyun@dgist.ac.kr.

ABSTRACT
In this study, we have fabricated and characterized the silicon [Si] wire solar cells with conformal ZnO nanorod antireflection coating [ARC] grown on a Al-doped ZnO [AZO] seed layer. Vertically aligned Si wire arrays were fabricated by electrochemical etching and, the p-n junction was prepared by spin-on dopant diffusion method. Hydrothermal growth of the ZnO nanorods was followed by AZO film deposition on high aspect ratio Si microwire arrays by atomic layer deposition [ALD]. The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination. The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering. Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it.

No MeSH data available.