Limits...
Superior broadband antireflection from buried Mie resonator arrays for high-efficiency photovoltaics.

Zhong S, Zeng Y, Huang Z, Shen W - Sci Rep (2015)

Bottom Line: Establishing reliable and efficient antireflection structures is of crucial importance for realizing high-performance optoelectronic devices such as solar cells.We find that the buried Mie resonator arrays mainly play a role as a transparent antireflection structure and their antireflection effect is insensitive to the nanostructure height when higher than 150 nm, which are of prominent significance for photovoltaic applications in the reduction of photoexcited carrier recombination.We further optimally combine the buried Mie resonator arrays with micron-scale textures to maximize the utilization of photons, and thus have successfully achieved an independently certified efficiency of 18.47% for the nanostructured silicon solar cells on a large-size wafer (156 mm × 156 mm).

View Article: PubMed Central - PubMed

Affiliation: Institute of Solar Energy, and Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.

ABSTRACT
Establishing reliable and efficient antireflection structures is of crucial importance for realizing high-performance optoelectronic devices such as solar cells. In this study, we provide a design guideline for buried Mie resonator arrays, which is composed of silicon nanostructures atop a silicon substrate and buried by a dielectric film, to attain a superior antireflection effect over a broadband spectral range by gaining entirely new discoveries of their antireflection behaviors. We find that the buried Mie resonator arrays mainly play a role as a transparent antireflection structure and their antireflection effect is insensitive to the nanostructure height when higher than 150 nm, which are of prominent significance for photovoltaic applications in the reduction of photoexcited carrier recombination. We further optimally combine the buried Mie resonator arrays with micron-scale textures to maximize the utilization of photons, and thus have successfully achieved an independently certified efficiency of 18.47% for the nanostructured silicon solar cells on a large-size wafer (156 mm × 156 mm).

No MeSH data available.


(a) Experimental reflectance of both the unburied and SiNx-film-buried multi-scale textures, in which the thickness of the SiNx film varies from 60 to 110 nm. (b) Current-voltage characteristic of the 18.47%-efficient multi-scale textured silicon solar cell, which is independently measured by the TÜV Rheinland Co., Ltd., official Test Report No. 15067482.001.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4352919&req=5

f8: (a) Experimental reflectance of both the unburied and SiNx-film-buried multi-scale textures, in which the thickness of the SiNx film varies from 60 to 110 nm. (b) Current-voltage characteristic of the 18.47%-efficient multi-scale textured silicon solar cell, which is independently measured by the TÜV Rheinland Co., Ltd., official Test Report No. 15067482.001.

Mentions: Based on the optimized surface morphology, we have further thoroughly investigated the reflectance properties of the SiNx-layer-buried multi-scale textures in experiments (here, the nanostructure height is controlled to be 100 nm). Just like the reflectance behaviors on a planar surface, Figure 8a shows that the reflectance of the SiNx-layer-buried multi-scale textures is remarkably reduced relative to that of the multi-scale textures without SiNx coating, which is ascribed to the enhanced antireflection effects from the SiNx layer. When the multi-scale textures are buried by an 80 nm SiNx film, an ultra-low reflectance over a broad wavelength (500–1000 nm) is achieved due to the best compromise of both the strong interference antireflection and forward scattering, resulting in the lowest Rave of 2.43% over the wavelength from 400 to 1100 nm. It is worth mentioning here that the ineffectiveness of the reflectance reduction by the 110-nm-SiNx-layer-buried multi-scale textures for wavelength larger than 1000 nm is probably due to the weak absorption of silicon in the wavelength range together with the thin wafer thickness of only 180 μm (in this case, the reflectance has no much relationship with the antireflection effects on the front surface, such as the forward scattering, due to the fact that the incident light can be easily reflected back from the back surface). Based on the optimized SiNx-layer-buried multi-scale textures, we have successfully achieved an η of 18.47% (equal to the maximum power of 4.414 W) for the large-scale nanostructured silicon solar cells with an area of 238.95 cm2 (156 mm × 156 mm), which is independently certified by the TÜV Rheinland Co., Ltd. and exhibited in Figure 8b. Comparing to the results in the Figure 5b, where the SiNPs are fabricated on the planar surfaces, a dramatic improvement in efficiency for the solar cells with the buried multi-scale textures benefits from the much lower carrier recombination (owing to the shorter silicon nanostructures), together with better antireflection effect.


Superior broadband antireflection from buried Mie resonator arrays for high-efficiency photovoltaics.

Zhong S, Zeng Y, Huang Z, Shen W - Sci Rep (2015)

(a) Experimental reflectance of both the unburied and SiNx-film-buried multi-scale textures, in which the thickness of the SiNx film varies from 60 to 110 nm. (b) Current-voltage characteristic of the 18.47%-efficient multi-scale textured silicon solar cell, which is independently measured by the TÜV Rheinland Co., Ltd., official Test Report No. 15067482.001.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4352919&req=5

f8: (a) Experimental reflectance of both the unburied and SiNx-film-buried multi-scale textures, in which the thickness of the SiNx film varies from 60 to 110 nm. (b) Current-voltage characteristic of the 18.47%-efficient multi-scale textured silicon solar cell, which is independently measured by the TÜV Rheinland Co., Ltd., official Test Report No. 15067482.001.
Mentions: Based on the optimized surface morphology, we have further thoroughly investigated the reflectance properties of the SiNx-layer-buried multi-scale textures in experiments (here, the nanostructure height is controlled to be 100 nm). Just like the reflectance behaviors on a planar surface, Figure 8a shows that the reflectance of the SiNx-layer-buried multi-scale textures is remarkably reduced relative to that of the multi-scale textures without SiNx coating, which is ascribed to the enhanced antireflection effects from the SiNx layer. When the multi-scale textures are buried by an 80 nm SiNx film, an ultra-low reflectance over a broad wavelength (500–1000 nm) is achieved due to the best compromise of both the strong interference antireflection and forward scattering, resulting in the lowest Rave of 2.43% over the wavelength from 400 to 1100 nm. It is worth mentioning here that the ineffectiveness of the reflectance reduction by the 110-nm-SiNx-layer-buried multi-scale textures for wavelength larger than 1000 nm is probably due to the weak absorption of silicon in the wavelength range together with the thin wafer thickness of only 180 μm (in this case, the reflectance has no much relationship with the antireflection effects on the front surface, such as the forward scattering, due to the fact that the incident light can be easily reflected back from the back surface). Based on the optimized SiNx-layer-buried multi-scale textures, we have successfully achieved an η of 18.47% (equal to the maximum power of 4.414 W) for the large-scale nanostructured silicon solar cells with an area of 238.95 cm2 (156 mm × 156 mm), which is independently certified by the TÜV Rheinland Co., Ltd. and exhibited in Figure 8b. Comparing to the results in the Figure 5b, where the SiNPs are fabricated on the planar surfaces, a dramatic improvement in efficiency for the solar cells with the buried multi-scale textures benefits from the much lower carrier recombination (owing to the shorter silicon nanostructures), together with better antireflection effect.

Bottom Line: Establishing reliable and efficient antireflection structures is of crucial importance for realizing high-performance optoelectronic devices such as solar cells.We find that the buried Mie resonator arrays mainly play a role as a transparent antireflection structure and their antireflection effect is insensitive to the nanostructure height when higher than 150 nm, which are of prominent significance for photovoltaic applications in the reduction of photoexcited carrier recombination.We further optimally combine the buried Mie resonator arrays with micron-scale textures to maximize the utilization of photons, and thus have successfully achieved an independently certified efficiency of 18.47% for the nanostructured silicon solar cells on a large-size wafer (156 mm × 156 mm).

View Article: PubMed Central - PubMed

Affiliation: Institute of Solar Energy, and Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.

ABSTRACT
Establishing reliable and efficient antireflection structures is of crucial importance for realizing high-performance optoelectronic devices such as solar cells. In this study, we provide a design guideline for buried Mie resonator arrays, which is composed of silicon nanostructures atop a silicon substrate and buried by a dielectric film, to attain a superior antireflection effect over a broadband spectral range by gaining entirely new discoveries of their antireflection behaviors. We find that the buried Mie resonator arrays mainly play a role as a transparent antireflection structure and their antireflection effect is insensitive to the nanostructure height when higher than 150 nm, which are of prominent significance for photovoltaic applications in the reduction of photoexcited carrier recombination. We further optimally combine the buried Mie resonator arrays with micron-scale textures to maximize the utilization of photons, and thus have successfully achieved an independently certified efficiency of 18.47% for the nanostructured silicon solar cells on a large-size wafer (156 mm × 156 mm).

No MeSH data available.