Details
| Original language | English |
|---|---|
| Article number | 7360866 |
| Pages (from-to) | 397-403 |
| Number of pages | 7 |
| Journal | IEEE journal of photovoltaics |
| Volume | 6 |
| Issue number | 2 |
| Early online date | 18 Dec 2015 |
| Publication status | Published - Mar 2016 |
Abstract
We fabricate a blind hole surface texture by anodic etching of macroporous Si. The blind holes, i.e., pores that do not penetrate the wafer completely, have an average diameter of 2.7 μm, a distance of 4 μm, and a depth of 9 μm. This texture is capable of reducing the AM1.5G photon flux-weighted front reflectance to 1.5% without depositing an antireflection coating. The μm-feature size makes it a less fragile alternative to common nm-sized black silicon structures. We passivate the blind holes by atomic layer deposited AlOx. The blind hole texture allows for a carrier lifetime of (2.2 ± 0.25) ms corresponding to an effective surface recombination velocity of (8 ± 1.5) cm/s with respect to the macroscopic front surface. A direct comparison of the optical performance and the surface passivation quality with a standard SiNx-coated random pyramid surface shows that blind holes allow for a relative efficiency gain of (3 ± 0.2)% when applied, e.g., in an otherwise perfect back-contacted solar cell.
Keywords
- Charge carrier lifetime, optical losses, optical reflectivity, Surface texture
ASJC Scopus subject areas
- Materials Science(all)
- Electronic, Optical and Magnetic Materials
- Physics and Astronomy(all)
- Condensed Matter Physics
- Engineering(all)
- Electrical and Electronic Engineering
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In: IEEE journal of photovoltaics, Vol. 6, No. 2, 7360866, 03.2016, p. 397-403.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Light Trapping and Surface Passivation of Micron-Scaled Macroporous Blind Holes
AU - Schafer, Soren
AU - Gemmel, Catherin
AU - Kajari-Schroder, Sarah
AU - Brendel, Rolf
N1 - Funding Information: The authors would like to thank Moises Garin from Univer- sitat Polit‘ecnica de Catalunya, Barcelona, Spain, for his help with the prestructuring process. S. Sch¤afer thanks M. Garin and R. Alcubilla from Universitat Polit‘ecnica de Catalunya, Barcelona, Spain, for their hospitality during a visiting intern- ship and for fruitful discussions. This work was supported by the Federal Ministry for Economic Affairs and Energy under the contract FKZ 0325461
PY - 2016/3
Y1 - 2016/3
N2 - We fabricate a blind hole surface texture by anodic etching of macroporous Si. The blind holes, i.e., pores that do not penetrate the wafer completely, have an average diameter of 2.7 μm, a distance of 4 μm, and a depth of 9 μm. This texture is capable of reducing the AM1.5G photon flux-weighted front reflectance to 1.5% without depositing an antireflection coating. The μm-feature size makes it a less fragile alternative to common nm-sized black silicon structures. We passivate the blind holes by atomic layer deposited AlOx. The blind hole texture allows for a carrier lifetime of (2.2 ± 0.25) ms corresponding to an effective surface recombination velocity of (8 ± 1.5) cm/s with respect to the macroscopic front surface. A direct comparison of the optical performance and the surface passivation quality with a standard SiNx-coated random pyramid surface shows that blind holes allow for a relative efficiency gain of (3 ± 0.2)% when applied, e.g., in an otherwise perfect back-contacted solar cell.
AB - We fabricate a blind hole surface texture by anodic etching of macroporous Si. The blind holes, i.e., pores that do not penetrate the wafer completely, have an average diameter of 2.7 μm, a distance of 4 μm, and a depth of 9 μm. This texture is capable of reducing the AM1.5G photon flux-weighted front reflectance to 1.5% without depositing an antireflection coating. The μm-feature size makes it a less fragile alternative to common nm-sized black silicon structures. We passivate the blind holes by atomic layer deposited AlOx. The blind hole texture allows for a carrier lifetime of (2.2 ± 0.25) ms corresponding to an effective surface recombination velocity of (8 ± 1.5) cm/s with respect to the macroscopic front surface. A direct comparison of the optical performance and the surface passivation quality with a standard SiNx-coated random pyramid surface shows that blind holes allow for a relative efficiency gain of (3 ± 0.2)% when applied, e.g., in an otherwise perfect back-contacted solar cell.
KW - Charge carrier lifetime
KW - optical losses
KW - optical reflectivity
KW - Surface texture
UR - http://www.scopus.com/inward/record.url?scp=84951335200&partnerID=8YFLogxK
U2 - 10.1109/JPHOTOV.2015.2505179
DO - 10.1109/JPHOTOV.2015.2505179
M3 - Article
AN - SCOPUS:84951335200
VL - 6
SP - 397
EP - 403
JO - IEEE journal of photovoltaics
JF - IEEE journal of photovoltaics
SN - 2156-3381
IS - 2
M1 - 7360866
ER -